Usefulness of anterior cervical fusion using titanium interbody cage for treatment of cervical degenerative disease with preoperative segmental kyphosis

PubMed Central

Hosoi, Kunihiko; Tonomura, Hitoshi; Takatori, Ryota; Nagae, Masateru; Mikami, Yasuo; Osawa, Toru; Arai, Yuji; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2017-01-01

Abstract Favorable bone fusion and clinical results have been reported for anterior cervical fusion (ACF) using titanium interbody cage (TIC). This method might induce postoperative subsidence and local kyphosis, but the relationship between radiological changes and preoperative local alignment is not known. The purpose of the present study is to investigate the impact of preoperative local alignment on the clinical and radiological outcomes of ACF using TIC. The study enrolled 36 patients (mean age 49.8 years) who underwent single-level ACF using TIC for cervical degenerative diseases. Patients were divided into 2 groups by preoperative segmental lordotic angle at the operative level: group L, ≥0° (n = 16); group K, <0° (n = 20). Clinical outcomes included recovery rate according to the Japanese Orthopaedic Association score and complication rates. Radiological assessment was conducted for the cervical and segmental lordotic angles, subsidence, and bone fusion. Mann–Whitney test and chi-square test were applied to compare the outcomes. The Japanese Orthopaedic Association score recovery rate was 77.2% in group L and 87.6% in group K, with no significant difference. No obvious complications were observed in any of the subjects. Mean cervical lordotic angles preoperatively and at last follow-up were 9.2 ± 9.5° and 11.3 ± 11.7°, respectively, in group L, and −1.3 ± 12.8° and 4.6 ± 13.3°, respectively, in group K. The mean segmental lordotic angles preoperatively and at last follow-up were 2.5 ± 2.2° and 2.6 ± 5.7°, respectively, in group L, and −4.5 ± 2.8° and −1.4 ± 5.8°, respectively, in group K. In group K, the cervical and segmental lordotic angles at the last follow-up were significantly greater than the preoperative angles. The change observed in group L was not significant. Subsidence of ≥3 mm was observed in 3 patients in group L and 4 patients in group K. None of the patients showed nonunion. Anterior cervical fusion using TIC provided favorable clinical results regardless of preoperative segmental alignment. Although postoperative subsidence and kyphotic changes are concerns in patients presenting segmental kyphosis, ACF using TIC corrected both the entire cervical spine and segmental alignment. The TIC is useful for correction of the cervical alignment for patients with cervical degenerative disease with local kyphotic changes. PMID:28796062

Biomechanics of coupled motion in the cervical spine during simulated whiplash in patients with pre-existing cervical or lumbar spinal fusion

PubMed Central

Huang, H.; Nightingale, R. W.

2018-01-01

Objectives Loss of motion following spine segment fusion results in increased strain in the adjacent motion segments. However, to date, studies on the biomechanics of the cervical spine have not assessed the role of coupled motions in the lumbar spine. Accordingly, we investigated the biomechanics of the cervical spine following cervical fusion and lumbar fusion during simulated whiplash using a whole-human finite element (FE) model to simulate coupled motions of the spine. Methods A previously validated FE model of the human body in the driver-occupant position was used to investigate cervical hyperextension injury. The cervical spine was subjected to simulated whiplash exposure in accordance with Euro NCAP (the European New Car Assessment Programme) testing using the whole human FE model. The coupled motions between the cervical spine and lumbar spine were assessed by evaluating the biomechanical effects of simulated cervical fusion and lumbar fusion. Results Peak anterior longitudinal ligament (ALL) strain ranged from 0.106 to 0.382 in a normal spine, and from 0.116 to 0.399 in a fused cervical spine. Strain increased from cranial to caudal levels. The mean strain increase in the motion segment immediately adjacent to the site of fusion from C2-C3 through C5-C6 was 26.1% and 50.8% following single- and two-level cervical fusion, respectively (p = 0.03, unpaired two-way t-test). Peak cervical strains following various lumbar-fusion procedures were 1.0% less than those seen in a healthy spine (p = 0.61, two-way ANOVA). Conclusion Cervical arthrodesis increases peak ALL strain in the adjacent motion segments. C3-4 experiences greater changes in strain than C6-7. Lumbar fusion did not have a significant effect on cervical spine strain. Cite this article: H. Huang, R. W. Nightingale, A. B. C. Dang. Biomechanics of coupled motion in the cervical spine during simulated whiplash in patients with pre-existing cervical or lumbar spinal fusion: A Finite Element Study. Bone Joint Res 2018;7:28–35. DOI: 10.1302/2046-3758.71.BJR-2017-0100.R1. PMID:29330341

Biomechanics of coupled motion in the cervical spine during simulated whiplash in patients with pre-existing cervical or lumbar spinal fusion: A Finite Element Study.

PubMed

Huang, H; Nightingale, R W; Dang, A B C

2018-01-01

Loss of motion following spine segment fusion results in increased strain in the adjacent motion segments. However, to date, studies on the biomechanics of the cervical spine have not assessed the role of coupled motions in the lumbar spine. Accordingly, we investigated the biomechanics of the cervical spine following cervical fusion and lumbar fusion during simulated whiplash using a whole-human finite element (FE) model to simulate coupled motions of the spine. A previously validated FE model of the human body in the driver-occupant position was used to investigate cervical hyperextension injury. The cervical spine was subjected to simulated whiplash exposure in accordance with Euro NCAP (the European New Car Assessment Programme) testing using the whole human FE model. The coupled motions between the cervical spine and lumbar spine were assessed by evaluating the biomechanical effects of simulated cervical fusion and lumbar fusion. Peak anterior longitudinal ligament (ALL) strain ranged from 0.106 to 0.382 in a normal spine, and from 0.116 to 0.399 in a fused cervical spine. Strain increased from cranial to caudal levels. The mean strain increase in the motion segment immediately adjacent to the site of fusion from C2-C3 through C5-C6 was 26.1% and 50.8% following single- and two-level cervical fusion, respectively (p = 0.03, unpaired two-way t -test). Peak cervical strains following various lumbar-fusion procedures were 1.0% less than those seen in a healthy spine (p = 0.61, two-way ANOVA). Cervical arthrodesis increases peak ALL strain in the adjacent motion segments. C3-4 experiences greater changes in strain than C6-7. Lumbar fusion did not have a significant effect on cervical spine strain. Cite this article : H. Huang, R. W. Nightingale, A. B. C. Dang. Biomechanics of coupled motion in the cervical spine during simulated whiplash in patients with pre-existing cervical or lumbar spinal fusion: A Finite Element Study. Bone Joint Res 2018;7:28-35. DOI: 10.1302/2046-3758.71.BJR-2017-0100.R1. © 2018 Huang et al.

Whole vertebral bone segmentation method with a statistical intensity-shape model based approach

NASA Astrophysics Data System (ADS)

Hanaoka, Shouhei; Fritscher, Karl; Schuler, Benedikt; Masutani, Yoshitaka; Hayashi, Naoto; Ohtomo, Kuni; Schubert, Rainer

2011-03-01

An automatic segmentation algorithm for the vertebrae in human body CT images is presented. Especially we focused on constructing and utilizing 4 different statistical intensity-shape combined models for the cervical, upper / lower thoracic and lumbar vertebrae, respectively. For this purpose, two previously reported methods were combined: a deformable model-based initial segmentation method and a statistical shape-intensity model-based precise segmentation method. The former is used as a pre-processing to detect the position and orientation of each vertebra, which determines the initial condition for the latter precise segmentation method. The precise segmentation method needs prior knowledge on both the intensities and the shapes of the objects. After PCA analysis of such shape-intensity expressions obtained from training image sets, vertebrae were parametrically modeled as a linear combination of the principal component vectors. The segmentation of each target vertebra was performed as fitting of this parametric model to the target image by maximum a posteriori estimation, combined with the geodesic active contour method. In the experimental result by using 10 cases, the initial segmentation was successful in 6 cases and only partially failed in 4 cases (2 in the cervical area and 2 in the lumbo-sacral). In the precise segmentation, the mean error distances were 2.078, 1.416, 0.777, 0.939 mm for cervical, upper and lower thoracic, lumbar spines, respectively. In conclusion, our automatic segmentation algorithm for the vertebrae in human body CT images showed a fair performance for cervical, thoracic and lumbar vertebrae.

Narrative review of the in vivo mechanics of the cervical spine after anterior arthrodesis as revealed by dynamic biplane radiography.

PubMed

Anderst, William

2016-01-01

Arthrodesis is the standard of care for numerous pathologic conditions of the cervical spine and is performed over 150,000 times annually in the United States. The primary long-term concern after this surgery is adjacent segment disease (ASD), defined as new clinical symptoms adjacent to a previous fusion. The incidence of adjacent segment disease is approximately 3% per year, meaning that within 10 years of the initial surgery, approximately 25% of cervical arthrodesis patients require a second procedure to address symptomatic adjacent segment degeneration. Despite the high incidence of ASD, until recently, there was little data available to characterize in vivo adjacent segment mechanics during dynamic motion. This manuscript reviews recent advances in our knowledge of adjacent segment mechanics after cervical arthrodesis that have been facilitated by the use of dynamic biplane radiography. The primary observations from these studies are that current in vitro test paradigms often fail to replicate in vivo spine mechanics before and after arthrodesis, that intervertebral mechanics vary among cervical motion segments, and that joint arthrokinematics (i.e., the interactions between adjacent vertebrae) are superior to traditional kinematics measurements for identifying altered adjacent segment mechanics after arthrodesis. Future research challenges are identified, including improving the biofidelity of in vitro tests, determining the natural history of in vivo spine mechanics, conducting prospective longitudinal studies on adjacent segment kinematics and arthrokinematics after single and multiple-level arthrodesis, and creating subject-specific computational models to accurately estimate muscle forces and tissue loading in the spine during dynamic activities. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

The Study of Cobb Angular Velocity in Cervical Spine during Dynamic Extension-Flexion.

PubMed

Ren, Dong; Hu, Zhihao; Yuan, Wen

2016-04-01

A kinematic study of cervical spine. The aim of the study was to confirm the interesting manifestation observed in the dynamic images of the cervical spine movement from full-extension to full-flexion. To further explore the fine motion of total process of cervical spine movement with the new concept of Cobb angular velocity (CAV). Traditionally range of motion (ROM) is used to describe the cervical spine movement from extension to flexion. It is performed with only end position radiographs. However, these radiographs fail to explain how the elaborate movement happens. The dynamic images of the cervical spine movement from full-extension to full-flexion of 12 asymptomatic subjects were collected. After transforming these dynamic images to static lateral radiographs, we overlapped C7 cervical vertebrae of each subject and divided the total process of cervical spine movement into five equal partitions. Finally, CAV values from C2/3 to C6/7 were measured and analyzed. A broken line graph was created based on the data of CAV values. A simple motion process was observed in C2/3 and C3/4 segments. The motion processes of C4/5 and C5/6 segments exhibited a more complex track of "N" and "W" than the other segments. The peak CAV values of C4/5 and C5/6 were significantly greater than the other segments. From C2/3 to C6/7, the peak CAV value appeared in sequence. The intervertebral movements of cervical spine did not take a uniform motion form when the cervical spine moved from full-extension to full-flexion. From C2/3 to C6/7, the peak CAV value appeared in order. The C4/5 and C5/6 segments exhibited more complex kinematic characteristics in sagittal movement. This leads to C4/5 and C5/6 more vulnerable to injury and degeneration. We had a hypothesis that there was a positive correlation between injury/degeneration and complexity of intervertebral movement in the view of CAV. N/A.

[Development and Validation of a Three-Dimensional Finite Element Model of Inferior Cervical Spinal Segments C(4-7) for a Healthy Person].

PubMed

Deng, Zhen; Wang, Huihao; Niu, Wenxin; Lan, Tianying; Wang, Kuan; Zhan, Hongsheng

2016-08-01

This study aims to develop and validate a three-dimensional finite element model of inferior cervical spinal segments C4-7of a healthy volunteer,and to provide a computational platform for investigating the biomechanical mechanism of treating cervical vertebra disease with Traditional Chinese Traumotology Manipulation(TCTM).A series of computed tomography(CT)images of C4-7segments were processed to establish the finite element model using softwares Mimics 17.0,Geromagic12.0,and Abaqus 6.13.A reference point(RP)was created on the endplate of C4 and coupled with all nodes of C4.All loads(±0.5,±1,±1.5and±2Nm)were added to the RP for the six simulations(flexion,extension,lateral bending and axial rotation).Then,the range of motion of each segment was calculated and compared with experimental measurements of in vitro studies.On the other hand,1Nm moment was loaded on the model to observe the main stress regions of the model in different status.We successfully established a detail model of inferior cervical spinal segments C4-7of a healthy volunteer with 591 459 elements and 121 446 nodes which contains the structure of the vertebra,intervertebral discs,ligaments and facet joints.The model showed an accordance result after the comparison with the in vitro studies in the six simulations.Moreover,the main stress region occurred on the model could reflect the main stress distribution of normal human cervical spine.The model is accurate and realistic which is consistent with the biomechanical properties of the cervical spine.The model can be used to explore the biomechanical mechanism of treating cervical vertebra disease with TCTM.

Cervical disc arthroplasty: Pros and cons.

PubMed

Moatz, Bradley; Tortolani, P Justin

2012-01-01

Cervical disc arthroplasty has emerged as a promising potential alternative to anterior cervical discectomy and fusion (ACDF) in appropriately selected patients. Despite a history of excellent outcomes after ACDF, the question as to whether a fusion leads to adjacent segment degeneration remains unanswered. Numerous US investigational device exemption trials comparing cervical arthroplasty to fusion have been conducted to answer this question. This study reviews the current research regarding cervical athroplasty, and emphasizes both the pros and cons of arthroplasty as compared with ACDF. Early clinical outcomes show that cervical arthroplasty is as effective as the standard ACDF. However, this new technology is also associated with an expanding list of novel complications. Although there is no definitive evidence that cervical disc replacement reduces the incidence of adjacent segment degeneration, it does show other advantages; for example, faster return to work, and reduced need for postoperative bracing.

Does cervical ureaplasma/mycoplasma colonization increase the lower uterine segment bleeding risk during cesarean section among patients with placenta previa? A cross-sectional study.

PubMed

Aydogan, P; Kahyaoglu, S; Saygan, S; Kaymak, O; Mollamahmutoglu, L; Danisman, N

2014-08-01

The underlying inflammation of endometrium may impede normal implantation of placenta during pregnancy. Our objective is to show cervical colonization of ureaplasma and/or mycoplasma as a marker of endometritis in pregnancies complicated with placenta previa that can be a risk factor for placenta accreta and peripartum hemorrhage. Cervical cultures for ureaplasma urealyticum and mycoplasma genitalium have been taken from the endocervical region of the cervix of the patients. Subsequent uterine lower segment bleeding suggesting placenta implantation defects have been evaluated during cesarean section. Of 25 patients: ten (40%) had negative cervical cultures for cervical mycoplasma and/or ureaplasma, 9 (36%) were found to be culture positive for cervical ureaplasma, 1 (4%) was found to be culture positive for cervical mycoplasma. Half of the 10 patients with positive cervical cultures for ureaplasma or mycoplasma and 6 of (40%) 15 patients with negative results had experienced lower uterine segment bleeding during cesarean section. Bacterial colonization of cervix in particular with ureaplasma and/or mycoplasma is found to be strongly associated with placenta previa. Before a planned pregnancy, treatment of this infection with appropriate antibiotics is necessary to prevent underlying uterine endometritis that increases the risk for abnormal implantation of placenta.

Clinical and Radiologic Features of 3 Reconstructive Procedures for the Surgical Management of Patients with Bilevel Cervical Degenerative Disc Disease at a Minimum Follow-Up Period of 5 Years: A Comparative Study.

PubMed

Wang, Kai-Feng; Duan, Shuo; Zhu, Zhen-Qi; Liu, Hai-Ying; Liu, Chen-Jun; Xu, Shuai

2018-05-01

To assess the mid-long-term follow-up of the safety and efficacy of anterior cervical discectomy and fusion (ACDF), cervical artificial disc replacement (CADR) and hybrid surgery (HS) for bilevel cervical degenerative disc disease (cDDD). 77 patients who underwent ACDF, HS, and CADR were retrospectively reviewed. Clinical effects were evaluated based on Neck Disability Index (NDI), Visual Analog Scale (VAS), and Japanese Orthopedic Association (JOA) scores and the Odom criteria. Radiographic outcomes were evaluated, including cervical range of motion (ROM), ROM in the operative and adjacent segments, incidence of degeneration in the adjacent segments (ASD), and heterotopic ossification (HO). NDI, VAS, and JOA scores significantly improved in all patients after surgery without significant differences between groups. The excellent-to-good ratio in the Odom scale was 28/30 for the HS group, 30/33 for the ACDF group, and 13/14 for the CADR group. No significant differences in clinical outcomes or complication were found between groups (P > 0.05). Furthermore, the HS and CADR groups had less decreased ROM in the cervical and operative segments and less compensatory ROM in adjacent segments (P < 0.05). By contrast, the ACDF group had decreased ROM in the cervical and operative segments and significantly increased ROM in adjacent segments (P < 0.05). Moreover, the incidence of ASD was higher in the ACDF group, but the difference was not statistically significant (P > 0.05). HO was found in 10 patients (33.3%) in the HS group and 5 patients (35.7%) in the CADR group. HS was superior to ACDF with regard to equivalent clinical outcomes in the mid-long-term follow-up. Furthermore, HS was superior in the maintenance of ROM and had less impact on its adjacent segments. The efficacy of HS is similar to that of CADR. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Relationship between screw sagittal angle and stress on endplate of adjacent segments after anterior cervical corpectomy and fusion with internal fixation: a Chinese finite element study.

PubMed

Zhang, Yu; Tang, Yibo; Shen, Hongxing

2017-12-01

In order to reduce the incidence of adjacent segment disease (ASD), the current study was designed to establish Chinese finite element models of normal 3rd~7th cervical vertebrae (C3-C7) and anterior cervical corpectomy and fusion (ACCF) with internal fixation , and analyze the influence of screw sagittal angle (SSA) on stress on endplate of adjacent cervical segments. Mimics 8.1 and Abaqus/CAE 6.10 softwares were adopted to establish finite element models. For C4 superior endplate and C6 inferior endplate, their anterior areas had the maximum stress in anteflexion position, and their posterior areas had the maximum stress in posterior extension position. As SSA increased, the stress reduced. With an increase of 10° in SSA, the stress on anterior areas of C4 superior endplate and C6 inferior endplate reduced by 12.67% and 7.99% in anteflexion position, respectively. With an increase of 10° in SSA, the stress on posterior areas of C4 superior endplate and C6 inferior endplate reduced by 9.68% and 10.22% in posterior extension position, respectively. The current study established Chinese finite element models of normal C3-C7 and ACCF with internal fixation , and demonstrated that as SSA increased, the stress on endplate of adjacent cervical segments decreased. In clinical surgery, increased SSA is able to play important role in protecting the adjacent cervical segments and reducing the incidence of ASD.

Adjacent Segment Disease After Cervical Spine Fusion: Evaluation of a 70 Patient Long-Term Follow-Up.

PubMed

Alhashash, Mohamed; Shousha, Mootaz; Boehm, Heinrich

2018-05-01

A retrospective study of 70 patients undergoing surgical treatment for adjacent segment disease (ASD) after anterior cervical decompression and fusion (ACDF). To analyze the risk factors for the development of ASD in patients who underwent ACDF. ACDF has provided a high rate of clinical success for the cervical degenerative disc disease; nevertheless, adjacent segment degeneration has been reported as a complication at the adjacent level secondary to the rigid fixation. Between January 2005 and December 2012, 70 consecutive patients underwent surgery for ASD after ACDF in our institution. In all patients thorough clinical and radiological examination was performed preoperatively, postoperatively, and at the final follow-up. The clinical data included the Neck Disability Index (NDI) and the Visual Analogue Scale (VAS). The radiological evaluation included x-rays and magnetic resonance imaging (MRI) for all patients. The duration of follow up after the adjacent segment operation ranged from 3 to 10 years. Surgery for ASD was performed after a mean period of 32 months from the primary ACDF. ASD occurred after single level ACDF in 54% of cases, most commonly after C5/6 fusion (28%). Risk factors for ASD were found to be preexisting radiological signs of degeneration at the primary surgery (74%) and bad sagittal profile after the primary ACDF (90%). ASD occurred predominantly in the middle cervical region (C4-6); especially in patients with preexisting evidence of radiological degeneration in the adjacent segment at the time of primary cervical fusion, notably when this surgery failed to restore or maintain the cervical lordosis. 4.

The Immediate Effects of Upper Thoracic Translatoric Spinal Manipulation on Cervical Pain and Range of Motion: A Randomized Clinical Trial

PubMed Central

Krauss, John; Creighton, Doug; Ely, Jonathan D.; Podlewska-Ely, Joanna

2008-01-01

This study examined the effect of translatoric spinal manipulation (TSM) on cervical pain and cervical active motion restriction when applied to upper thoracic (T1-T4) segments. Active cervical rotation range of motion was measured re- and post-intervention with a cervical inclinometer (CROM), and cervical pain status was monitored before and after manipulation with a Faces Pain Scale. Study participants included a sample of convenience that included 32 patients referred to physical therapy with complaints of pain in the mid-cervical region and restricted active cervical rotation. Twenty-two patients were randomly assigned to the experimental group and ten were assigned to the control group. Pre- and post-intervention cervical range of motion and pain scale measurements were taken by a physical therapist assistant who was blinded to group assignment. The experimental group received TSM to hypomobile upper thoracic segments. The control group received no intervention. Paired t-tests were used to analyze within-group changes in cervical rotation and pain, and a 2-way repeated-measure ANOVA was used to analyze between-group differences in cervical rotation and pain. Significance was accepted at p = 0.05. Significant changes that exceeded the MDC95 were detected for cervical rotation both within group and between groups with the TSM group demonstrating increased mean (SD) in right rotation of 8.23° (7.41°) and left rotation of 7.09° (5.83°). Pain levels perceived during post-intervention cervical rotation showed significant improvement during right rotation for patients experiencing pain during bilateral rotation only (p=.05). This study supports the hypothesis that spinal manipulation applied to the upper thoracic spine (T1-T4 motion segments) significantly increases cervical rotation ROM and may reduce cervical pain at end range rotation for patients experiencing pain during bilateral cervical rotation. PMID:19119394

Cervical disc arthroplasty: Pros and cons

PubMed Central

Moatz, Bradley; Tortolani, P. Justin

2012-01-01

Background: Cervical disc arthroplasty has emerged as a promising potential alternative to anterior cervical discectomy and fusion (ACDF) in appropriately selected patients. Despite a history of excellent outcomes after ACDF, the question as to whether a fusion leads to adjacent segment degeneration remains unanswered. Numerous US investigational device exemption trials comparing cervical arthroplasty to fusion have been conducted to answer this question. Methods: This study reviews the current research regarding cervical athroplasty, and emphasizes both the pros and cons of arthroplasty as compared with ACDF. Results: Early clinical outcomes show that cervical arthroplasty is as effective as the standard ACDF. However, this new technology is also associated with an expanding list of novel complications. Conclusion: Although there is no definitive evidence that cervical disc replacement reduces the incidence of adjacent segment degeneration, it does show other advantages; for example, faster return to work, and reduced need for postoperative bracing. PMID:22905327

Fully automatic cervical vertebrae segmentation framework for X-ray images.

PubMed

Al Arif, S M Masudur Rahman; Knapp, Karen; Slabaugh, Greg

2018-04-01

The cervical spine is a highly flexible anatomy and therefore vulnerable to injuries. Unfortunately, a large number of injuries in lateral cervical X-ray images remain undiagnosed due to human errors. Computer-aided injury detection has the potential to reduce the risk of misdiagnosis. Towards building an automatic injury detection system, in this paper, we propose a deep learning-based fully automatic framework for segmentation of cervical vertebrae in X-ray images. The framework first localizes the spinal region in the image using a deep fully convolutional neural network. Then vertebra centers are localized using a novel deep probabilistic spatial regression network. Finally, a novel shape-aware deep segmentation network is used to segment the vertebrae in the image. The framework can take an X-ray image and produce a vertebrae segmentation result without any manual intervention. Each block of the fully automatic framework has been trained on a set of 124 X-ray images and tested on another 172 images, all collected from real-life hospital emergency rooms. A Dice similarity coefficient of 0.84 and a shape error of 1.69 mm have been achieved. Copyright © 2018 Elsevier B.V. All rights reserved.

Improving cervical region of interest by eliminating vaginal walls and cotton-swabs for automated image analysis

NASA Astrophysics Data System (ADS)

Venkataraman, Sankar; Li, Wenjing

2008-03-01

Image analysis for automated diagnosis of cervical cancer has attained high prominence in the last decade. Automated image analysis at all levels requires a basic segmentation of the region of interest (ROI) within a given image. The precision of the diagnosis is often reflected by the precision in detecting the initial region of interest, especially when some features outside the ROI mimic the ones within the same. Work described here discusses algorithms that are used to improve the cervical region of interest as a part of automated cervical image diagnosis. A vital visual aid in diagnosing cervical cancer is the aceto-whitening of the cervix after the application of acetic acid. Color and texture are used to segment acetowhite regions within the cervical ROI. Vaginal walls along with cottonswabs sometimes mimic these essential features leading to several false positives. Work presented here is focused towards detecting in-focus vaginal wall boundaries and then extrapolating them to exclude vaginal walls from the cervical ROI. In addition, discussed here is a marker-controlled watershed segmentation that is used to detect cottonswabs from the cervical ROI. A dataset comprising 50 high resolution images of the cervix acquired after 60 seconds of acetic acid application were used to test the algorithm. Out of the 50 images, 27 benefited from a new cervical ROI. Significant improvement in overall diagnosis was observed in these images as false positives caused by features outside the actual ROI mimicking acetowhite region were eliminated.

A Comparison of Zero-Profile Devices and Artificial Cervical Disks in Patients With 2 Noncontiguous Levels of Cervical Spondylosis.

PubMed

Qizhi, Sun; Lei, Sun; Peijia, Li; Hanping, Zhao; Hongwei, Hu; Junsheng, Chen; Jianmin, Li

2016-03-01

A prospective randomized and controlled study of 30 patients with 2 noncontiguous levels of cervical spondylosis. To compare the clinical outcome between zero-profile devices and artificial cervical disks for noncontiguous cervical spondylosis. Noncontiguous cervical spondylosis is an especial degenerative disease of the cervical spine. Some controversy exists over the choice of surgical procedure and fusion levels for it because of the viewpoint that the stress at levels adjacent to a fusion mass will increase. The increased stress will lead to the adjacent segment degeneration (ASD). According to the viewpoint, the intermediate segment will bear more stress after both superior and inferior segments' fusion. Cervical disk arthroplasty is an alternative to fusion because of its motion-preserving. Few comparative studies have been conducted on arthrodesis with zero-prolife devices and arthroplasty with artificial cervical disks for noncontiguous cervical spondylosis. Thirty patients with 2 noncontiguous levels of cervical spondylosis were enrolled and assigned to either group A (receiving arthroplasty using artificial cervical disks) and group Z (receiving arthrodesis using zero-profile devices). The clinical outcomes were assessed by the mean operative time, blood loss, Japanese Orthopedic Association (JOA) score, Neck Dysfunction Index (NDI), cervical lordosis, fusion rate, and complications. The mean follow-up was 32.4 months. There were no significant differences between the 2 groups in the blood loss, JOA score, NDI score, and cervical lordosis except operative time. The mean operative time of group A was shorter than that of group Z. Both the 2 groups demonstrated a significant increase in JOA score, NDI score, and cervical lordosis. The fusion rate was 100% at 12 months postoperatively in group Z. There was no significant difference between the 2 groups in complications except the ASD. Three patients had radiologic ASD at the final follow-up in group Z, and none in group A. Both zero-prolife devices and artificial cervical disks are generally effective and safe in the treatment of 2 noncontiguous levels of cervical spondylosis. However, in view of occurrence of the radiologic ASD and operative time, we prefer to artificial cervical disks if indications are well controlled.

Investigation of motorcyclist cervical spine trauma using HUMOS model.

PubMed

Sun, Jingchao; Rojas, Alban; Bertrand, Pierre; Petit, Yvan; Kraenzler, Reinhard; Arnoux, Pierre Jean

2012-09-01

With 16 percent of the total road user fatalities, motorcyclists represent the second highest rate of road fatalities in France after car occupants. Regarding road accidents, a large proportion of trauma was on the lower cervical spine. According to different clinical studies, it is postulated that the cervical spine fragility areas are located on the upper and lower cervical spine. In motorcycle crashes, impact conditions occur on the head segment with various orientations and impact directions, leading to a combination of rotations and compression. Hence, motorcyclist vulnerability was investigated considering many impact conditions. Using the human model for safety (HUMOS), a finite element model, this work aims to provide an evaluation of the cervical spine weaknesses based on an evaluation of injury mechanisms. This evaluation consisted of defining 2 injury risk factors (joint injury and bone fracture) using a design of experiment including various velocities, impact directions, and impact orientations. The results confirmed previously reported clinical and epidemiological work on the fragility of the lower cervical spine and the upper cervical spine segments. Joint injuries appeared before bone fractures on both the upper and lower cervical spine. Bone fracture risk was greater on the lower cervical spine than on the upper cervical spine. The compression induced by a high impact angle was identified as an important injury severity factor. It significantly increased the injury incidence for both joint injuries and bone fractures. It also induced a shift in injury location from the lower to the upper cervical spine. The impact velocity exhibited a linear relationship with injury risks and severity. It also shifted the bone fracture risk from the lower to upper spinal segments.

Reliability and scientific use of a surgical planning software for anterior cervical discectomy and fusion (ACDF).

PubMed

Barth, Martin; Weiß, Christel; Brenke, Christopher; Schmieder, Kirsten

2017-04-01

Software-based planning of a spinal implant inheres in the promise of precision and superior results. The purpose of the study was to analyze the measurement reliability, prognostic value, and scientific use of a surgical planning software in patients receiving anterior cervical discectomy and fusion (ACDF). Lateral neutral, flexion, and extension radiographs of patients receiving tailored cages as suggested by the planning software were available for analysis. Differences of vertebral wedging angles and segmental height of all cervical segments were determined at different timepoints using intraclass correlation coefficients (ICC). Cervical lordosis (C2/C7), segmental heights, global, and segmental range of motion (ROM) were determined at different timepoints. Clinical and radiological variables were correlated 12 months after surgery. 282 radiographs of 35 patients with a mean age of 53.1 ± 12.0 years were analyzed. Measurement of segmental height was highly accurate with an ICC near to 1, but angle measurements showed low ICC values. Likewise, the ICCs of the prognosticated values were low. Postoperatively, there was a significant decrease of segmental height (p < 0.0001) and loss of C2/C7 ROM (p = 0.036). ROM of unfused segments also significantly decreased (p = 0.016). High NDI was associated with low subsidence rates. The surgical planning software showed high accuracy in the measurement of height differences and lower accuracy values with angle measurements. Both the prognosticated height and angle values were arbitrary. Global ROM, ROM of the fused and intact segments, is restricted after ACDF.

Localisation of the spinal nucleus of the accessory nerve in the rabbit.

PubMed Central

Ullah, M; Salman, S S

1986-01-01

The spinal nucleus of the accessory nerve (SNA) was localised in eight adult rabbits by a retrograde degeneration technique using thionine as a stain for the Nissl substance. The SNA was found to extend from the caudal one fifth of the medulla oblongata to the cranial one fourth of the sixth cervical segment. In the caudal part of the medulla oblongata, the SNA was located in the dorsal part of the detached ventral grey column. In the first cervical segment, the SNA was dorsolateral to the dorsomedial column and dorsal to the ventromedial column of the ventral grey column. In the cranial part of the second cervical segment, the SNA shifted laterally to the lateral margin of the ventral grey column. After this lateral shift, the SNA was located in the lateral part of the ventral grey column of the second, third and fourth cervical segments. In the fifth and cranial one fourth of the sixth cervical segments, the SNA was not a well defined column of cells but was represented by isolated cells scattered in the ventral part of the ventral grey column between the phrenic nucleus and the ventral border of the grey matter. The total number of chromatolysed cells found in the SNA of the right experimental side varied from 2723 to 3210. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 PMID:3429311

The deformation behavior of the cervical spine segment

NASA Astrophysics Data System (ADS)

Kolmakova, T. V.; Rikun, Yu. A.

2017-09-01

The paper describes the model of the cervical spine segment (C3-C4) and the calculation results of its deformation behavior at flexion. The segment model was built based on the experimental literature data taking into account the presence of the cortical and cancellous bone tissue of vertebral bodies. Degenerative changes of the intervertebral disk (IVD) were simulated through a reduction of the disc height and an increase of Young's modulus. The construction of the geometric model of the cervical spine segment and the calculations of the stress-strain state were carried out in the ANSYS software complex. The calculation results show that the biggest protrusion of the IVD in bending direction of segment is observed when IVD height is reduced. The disc protrusion is reduced with an increase of Young's modulus. The largest protrusion in the direction of flexion of the segment is the intervertebral disk with height of 4.3 mm and elastic modulus of 2.5 MPa. The results of the study can be useful to specialists in the field of biomechanics, medical materials science and prosthetics.

A Prospective Study of Clinical and Radiological Outcomes of Zero-Profile Cage Screw Implants for Single-Level Anterior Cervical Discectomy and Fusion: Is Segmental Lordosis Maintained at 2 Years?

PubMed

Basu, Saumyajit; Rathinavelu, Sreeramalingam

2017-04-01

Prospective cohort study. To study clinicoradiological parameters of zero-profile cage screw used for anterior cervical discectomy and fusion (ACDF). Radiological parameters of various implants used for ACDF are available, but those for zero-profile cage are sparse. Patients with unilateral intractable brachialgia due to single-level cervical disc prolapse between April 1, 2011 and March 31, 2014 were included. Clinical assessment included arm and neck pain using visual analogue score (VAS) and neck disability index (NDI) scores. Radiological assessment included motion segment height, adjacent disc height (upper and lower), segmental and cervical lordosis, implant subsidence, and pseudoarthrosis. Follow-ups were scheduled at 1, 3, 6, 12, and 24 months. Thirty-four patients (26 males, 8 females) aged 30-50 years (mean, 42.2) showed excellent clinical improvement based on VAS scores (7.4-0 for arm and 2.0-0.6 for neck pains). Postoperative disc height improved by 11.33% ( p <0.001), but at 2 years, the score deteriorated by 7.03% ( p <0.001). Difference in the adjacent segment disc height at 2 years was 0.08% ( p =0.8) in upper and 0.16% ( p <0.001) in lower disc spaces. Average segmental lordosis achieved was 5.59° ( p <0.001) from a preoperative kyphosis of 0.88°; at 2 years, an average loss of 7.05° ( p <0.001) occurred, resulting in an average segmental kyphosis of 1.38°. Cervical lordosis improved from 11.59° to 14.88° ( p =0.164), and at 2 years, it progressively improved to 22.59° ( p <0.001). Three patients showed bone formation and two mild protrusion of the implant at 2 years without pseudoarthrosis/implant failure. The zero-profile cage screw device provides good fusion and cervical lordosis but is incapable of maintaining the segmental lordosis achieved up to a 2-year follow-up. We also recommend caution when using it in patients with small vertebrae.

Improved segmentation of abnormal cervical nuclei using a graph-search based approach

NASA Astrophysics Data System (ADS)

Zhang, Ling; Liu, Shaoxiong; Wang, Tianfu; Chen, Siping; Sonka, Milan

2015-03-01

Reliable segmentation of abnormal nuclei in cervical cytology is of paramount importance in automation-assisted screening techniques. This paper presents a general method for improving the segmentation of abnormal nuclei using a graph-search based approach. More specifically, the proposed method focuses on the improvement of coarse (initial) segmentation. The improvement relies on a transform that maps round-like border in the Cartesian coordinate system into lines in the polar coordinate system. The costs consisting of nucleus-specific edge and region information are assigned to the nodes. The globally optimal path in the constructed graph is then identified by dynamic programming. We have tested the proposed method on abnormal nuclei from two cervical cell image datasets, Herlev and H and E stained liquid-based cytology (HELBC), and the comparative experiments with recent state-of-the-art approaches demonstrate the superior performance of the proposed method.

Anterior cervical corpectomy for cervical spondylotic myelopathy: Reconstruction with expandable cylindrical cage versus iliac crest autograft. A retrospective study.

PubMed

Perrini, Paolo; Gambacciani, Carlo; Martini, Carlotta; Montemurro, Nicola; Lepori, Paolo

2015-12-01

To compare retrospectively the clinical and radiographic outcomes between cervical reconstruction with expandable cylindrical cage (ECC) and iliac crest autograft after one- or two-level anterior cervical corpectomy for spondylotic myelopathy. Forty-two patients underwent cervical reconstruction with either iliac crest autograft and plating (20 patients) or ECC and plating (22 patients). The average clinical and radiological follow-up period was 77.54 ± 44.28 months (range 14-155 months). The authors compared clinical parameters (Nurick Myelopathy Grade, modified Japanese Orthopedic Association (mJOA) scores), perioperative parameters (hospital stays, complications) and radiological parameters (Cobb's angles of the fused segments and C2-C7 segments, cervical subsidence, fusion rate). Fusion was assessed on flexion-extension X-ray films. No significant differences between the two groups were found in demographics, neurological presentation, preoperative sagittal alignment, clinical improvement and length of hospitalization. Patients of the autograft group experienced more postoperative complications, although the difference between the two treatment groups was not statistically significant (15 versus 4.5%, p=0.232). The fusion rate was 100% in both groups. The average lordotic increase of the segmental angle was significantly greater in the ECC group (p<0.05). Other radiological parameters were not significantly different in the two groups. Cervical reconstruction either with iliac crest autograft and plating or ECC and plating provides good clinical results and similar fusion rates after one- or two-level corpectomy for spondylotic myelopathy. However, the use of ECC obviates donor site complications and provides a more significant increase of lordosis in segmental angle. Copyright © 2015 Elsevier B.V. All rights reserved.

Fast and accurate semi-automated segmentation method of spinal cord MR images at 3T applied to the construction of a cervical spinal cord template.

PubMed

El Mendili, Mohamed-Mounir; Chen, Raphaël; Tiret, Brice; Villard, Noémie; Trunet, Stéphanie; Pélégrini-Issac, Mélanie; Lehéricy, Stéphane; Pradat, Pierre-François; Benali, Habib

2015-01-01

To design a fast and accurate semi-automated segmentation method for spinal cord 3T MR images and to construct a template of the cervical spinal cord. A semi-automated double threshold-based method (DTbM) was proposed enabling both cross-sectional and volumetric measures from 3D T2-weighted turbo spin echo MR scans of the spinal cord at 3T. Eighty-two healthy subjects, 10 patients with amyotrophic lateral sclerosis, 10 with spinal muscular atrophy and 10 with spinal cord injuries were studied. DTbM was compared with active surface method (ASM), threshold-based method (TbM) and manual outlining (ground truth). Accuracy of segmentations was scored visually by a radiologist in cervical and thoracic cord regions. Accuracy was also quantified at the cervical and thoracic levels as well as at C2 vertebral level. To construct a cervical template from healthy subjects' images (n=59), a standardization pipeline was designed leading to well-centered straight spinal cord images and accurate probability tissue map. Visual scoring showed better performance for DTbM than for ASM. Mean Dice similarity coefficient (DSC) was 95.71% for DTbM and 90.78% for ASM at the cervical level and 94.27% for DTbM and 89.93% for ASM at the thoracic level. Finally, at C2 vertebral level, mean DSC was 97.98% for DTbM compared with 98.02% for TbM and 96.76% for ASM. DTbM showed similar accuracy compared with TbM, but with the advantage of limited manual interaction. A semi-automated segmentation method with limited manual intervention was introduced and validated on 3T images, enabling the construction of a cervical spinal cord template.

Anterior cervical discectomy and fusion (ACDF) versus cervical disc arthroplasty (CDA) for two contiguous levels cervical disc degenerative disease: a meta-analysis of randomized controlled trials.

PubMed

Zou, Shihua; Gao, Junyi; Xu, Bin; Lu, Xiangdong; Han, Yongbin; Meng, Hui

2017-04-01

Anterior cervical discectomy and fusion (ACDF) has been considered as a gold standard for symptomatic cervical disc degeneration (CDD), which may result in progressive degeneration of the adjacent segments. The artificial cervical disc was designed to reduce the number of lesions in the adjacent segments. Clinical studies have demonstrated equivalence of cervical disc arthroplasty (CDA) for anterior cervical discectomy and fusion in single segment cervical disc degeneration. But for two contiguous levels cervical disc degeneration (CDD), which kind of treatment method is better is controversial. To evaluate the clinical effects requiring surgical intervention between anterior cervical discectomy and fusion (ACDF) and cervical disc arthroplasty (CDA) at two contiguous levels cervical disc degeneration. We conducted a comprehensive search in multiple databases, including PubMed, Cochrane Central Register of Controlled Trials, EBSCO and EMBASE. We identified that six reports meet inclusion criteria. Two independent reviewers performed the data extraction from archives. Data analysis was conducted with RevMan 5.3. After applying inclusion and exclusion criteria, six papers were included in meta-analyses. The overall sample size at baseline was 650 patients (317 in the TDR group and 333 in the ACDF group). The results of the meta-analysis indicated that the CDA patients had significant superiorities in mean blood loss (P < 0.00001, standard mean differences (SMD) = -0.85, 95 % confidence interval (CI) = -1.22 to -0.48); reoperation (P = 0.0009, risk ratio (RR) = 0.28, 95 % confidence interval (CI) = 0.13-0.59), adjacent segment degeneration (P < 0.00001, risk ratio (RR) = 0.48, 95 % confidence interval (CI) = 0.40-0.58) and Neck Disability Index (P = 0.002, SMD = 0.31, 95 % CI = 0.12-0.50). No significant difference was identified between the two groups regarding mean surgical time (P = 0.84, SMD = -0.04, 95 % CI = -0.40 to 0.32), neck and arm pain scores (P = 0.52, SMD = 0.06, 95 % CI = -0.13 to 0.25) reported on a visual analog scale and rate of postoperative complications [risk ratio (RR) = 0.79; 95 % CI = 0.50-1.25; P = 0.31]. The CDA group of sagittal range of motion (ROM) of the operated and adjacent levels, functional segment units (FSU) and C2-7 is superior to ACDF group by radiographic data of peroperation, postoperation and follow-up. We can learn from this meta-analysis that the cervical disc arthroplasty (CDA) group is equivalent and in some aspects has more significant clinical outcomes than the ACDF group at two contiguous levels CDD.

Head posture and cervicovertebral and craniofacial morphology in patients with craniomandibular dysfunction.

PubMed

Huggare, J A; Raustia, A M

1992-07-01

A relationship between particular characteristics of dental occlusion and craniomandibular disorders (CMD) has been reported, while less attention has been focused on the possible effect of dysfunction of the masticatory system on head posture or cervicovertebral and craniofacial morphology. Natural head position roentgen-cephalograms of 16 young adults with complete dentition taken before and after stomatognathic treatment displayed an extended head posture, smaller size of the uppermost cervical vertebrae, decreased posterior to anterior face height ratio, and a flattened cranial base as compared with age- and sex-matched healthy controls. The lordosis of the cervical spine straightened after stomatognathic treatment. The results are an indication of the close interrelationship between the masticatory muscle system and the muscles supporting the head, and lead to speculation on the principles of treating craniomandibular disorders.

Dimensional coordinate measurements: application in characterizing cervical spine motion

NASA Astrophysics Data System (ADS)

Zheng, Weilong; Li, Linan; Wang, Shibin; Wang, Zhiyong; Shi, Nianke; Xue, Yuan

2014-06-01

Cervical spine as a complicated part in the human body, the form of its movement is diverse. The movements of the segments of vertebrae are three-dimensional, and it is reflected in the changes of the angle between two joint and the displacement in different directions. Under normal conditions, cervical can flex, extend, lateral flex and rotate. For there is no relative motion between measuring marks fixed on one segment of cervical vertebra, the cervical vertebrae with three marked points can be seen as a body. Body's motion in space can be decomposed into translational movement and rotational movement around a base point .This study concerns the calculation of dimensional coordinate of the marked points pasted to the human body's cervical spine by an optical method. Afterward, these measures will allow the calculation of motion parameters for every spine segment. For this study, we choose a three-dimensional measurement method based on binocular stereo vision. The object with marked points is placed in front of the CCD camera. Through each shot, we will get there two parallax images taken from different cameras. According to the principle of binocular vision we can be realized three-dimensional measurements. Cameras are erected parallelly. This paper describes the layout of experimental system and a mathematical model to get the coordinates.

Hybrid Method of Transvertebral Foraminotomy Combined with Anterior Cervical Decompression and Fusion for Multilevel Cervical Disease.

PubMed

Yamamoto, Yu; Hara, Masahito; Nishimura, Yusuke; Haimoto, Shoichi; Wakabayashi, Toshihiko

2018-03-15

Transvertebral foraminotomy (TVF) combined with anterior cervical decompression and fusion (ACDF) can be used to treat multilevel cervical spondylotic myelopathy and radiculopathy; however, the radiological outcomes and effectiveness of this hybrid procedure are unknown. We retrospectively assessed 22 consecutive patients treated with combined TVF and ACDF between January 2007 and May 2016. The Japanese Orthopedic Association (JOA) score and Odom's criteria were analyzed. Radiological assessment included the C2-7 sagittal Cobb angle (CA) and range of motion (ROM). The tilting angle (TA), TA ROM, and disc height (DH) of segments adjacent to the ACDF were also measured. Adjacent segment degeneration, which includes disc degeneration, was evaluated. The mean postoperative follow-up was 41.7 months. All surgeries were performed at two adjacent segments, with ACDF and TVF of the upper and lower segments, respectively. The JOA scores significantly improved. There were no significant differences in the C2-7 CA, C2-7 ROM, TA, and TA ROM, but there was a statistically significant decrease in DH of the lower adjacent segment to ACDF. Progression of disc degeneration was identified in two patients, with no progression in the criterion of adjacent segment degeneration over the follow-up. The TVF combined with ACDF produced excellent clinical results and maintained spinal alignment, albeit with a reduction in DH. TVF was safely performed at the lower segment adjacent to the ACDF, although this might result in earlier degeneration. In conclusion, this hybrid method is less invasive and beneficial for reduction of the number of fused levels.

Widespread spinal cord involvement in progressive supranuclear palsy.

PubMed

Iwasaki, Yasushi; Yoshida, Mari; Hashizume, Yoshio; Hattori, Manabu; Aiba, Ikuko; Sobue, Gen

2007-08-01

We describe the histopathologic features of spinal cord lesions in 10 cases of progressive supranuclear palsy (PSP) and review the literature. Histologic examination revealed atrophy with myelin pallor in the anterior funiculus and anterolateral funiculus in the cervical and thoracic segments in eight of the 10 cases, whereas the posterior funiculus was well preserved. The degrees of atrophy of the anterior funiculus and the anterolateral funiculus correlated with that of the tegmentum of the medulla oblongata. Myelin pallor of the lateral corticospinal tract was observed in two of the 10 cases. Microscopic observation of the spinal white matter, particularly the cervical segment, revealed a few to several neuropil threads, particularly in the white matter surrounding the anterior horn after Gallyas-Braak (GB) staining or AT-8 tau immunostaining. However, the posterior funiculus was completely preserved from the presence of argyrophilic or tau-positive structures. In the spinal gray matter, widespread distribution of neurons with cytoplasmic inclusions and neuropil threads was observed, particularly in the medial division of the anterior horn and intermediate gray matter, especially in the cervical segment. Globose-type neurofibrillary tangles and pretangles were found. The distribution of GB- or AT-8 tau-positive small neurons and neuropil threads resembled that of the spinal interneurons. In conclusion, the spinal cord, especially the cervical segment, is constantly involved in the pathologic process of PSP. We speculate that spinal interneurons and their neuronal processes, particularly in the medial division of the anterior horn and intermediate gray matter of the cervical segment, are most severely damaged in the PSP spinal cord.

Influence of neck postural changes on cervical spine motion and angle during swallowing

PubMed Central

Kim, Jun Young; Hong, Jae Taek; Oh, Joo Seon; Jain, Ashish; Kim, Il Sup; Lim, Seong Hoon; Kim, Jun Sung

2017-01-01

Abstract Occipitocervical (OC) fixation in a neck retraction position could be dangerous due to the risk of postoperative dysphagia. No previous study has demonstrated an association between the cervical posture change and cervical spine motion/angle during swallowing. So, we aimed to analyze the influence of neck posture on the cervical spine motion and angle change during swallowing. Thirty-seven asymptomatic volunteers were recruited for participation this study. A videoflurographic swallowing study was performed in the neutral and retracted neck posture. We analyzed the images of the oral and pharyngeal phases of swallowing and compared the angle and the position changes of each cervical segment. In the neutral posture, C1 and C2 were flexed, while C5, C6, and C7 were extended. C3, C4, C5, C6, and C7 moved posteriorly. All cervical levels, except for C5, moved superiorly. In the retraction posture, C0 and C1 were flexed, while C6 was extended during swallowing. All cervical levels moved posteriorly. C1, C2, C3, and C4 moved superiorly. The comparison between 2 postures shows that angle change is significantly different between C0, C2, and C5. Posterior translation change is significantly different in the upper cervical spine (C0, C1, and C2) and C7. Superior movement is significantly different in C0. C0 segment is most significantly different between neutral and retraction posture in terms of angle and position change. These data suggest that C0 segment could be a critical level of compensation that allows swallowing even in the retraction neck posture regarding motion and angle change. So, it is important not to do OC fixation in retraction posture. Also, sparing C0 segment could provide some degree of freedom for the compensatory movement and angle change to avoid dysphagia after OC fixation. PMID:29137075

Is the behavior of disc replacement adjacent to fusion affected by the location of the fused level in hybrid surgery?

PubMed

Wu, Ting-Kui; Meng, Yang; Wang, Bei-Yu; Hong, Ying; Rong, Xin; Ding, Chen; Chen, Hua; Liu, Hao

2018-04-27

Hybrid surgery (HS), consisting of cervical disc arthroplasty (CDA) at the mobile level, along with anterior cervical discectomy and fusion at the spondylotic level, could be a promising treatment for patients with multilevel cervical degenerative disc disease (DDD). An advantage of this technique is that it uses an optimal procedure according to the status of each level. However, information is lacking regarding the influence of the relative location of the replacement and the fusion segment in vivo. We conducted the present study to investigate whether the location of the fusion affected the behavior of the disc replacement and adjacent segments in HS in vivo. This is an observational study. The numbers of patients in the arthroplasty-fusion (AF) and fusion-arthroplasty (FA) groups were 51 and 24, respectively. The Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), and Visual Analog Scale (VAS) scores were evaluated. Global and segmental lordosis, the range of motion (ROM) of C2-C7, and the operated and adjacent segments were measured. Fusion rate and radiological changes at adjacent levels were observed. Between January 2010 and July 2016, 75 patients with cervical DDD at two contiguous levels undergoing a two-level HS were retrospectively reviewed. The patients were divided into AF and FA groups according to the locations of the disc replacement. Clinical outcomes were evaluated according to the JOA, NDI, and VAS scores. Radiological parameters, including global and segmental lordosis, the ROM of C2-C7, the operated and adjacent segments, and complications, were also evaluated. Although the JOA, NDI, and VAS scores were improved in both the AF and the FA groups, no significant differences were found between the two groups at any follow-up point. Both groups maintained cervical lordosis, but no difference was found between the groups. Segmental lordosis at the fusion segment was significantly improved postoperatively (p<.001), whereas it was maintained at the arthroplasty segment. The ROM of C2-C7 was significantly decreased in both groups postoperatively (AF p=.001, FA p=.014), but no difference was found between the groups. The FA group exhibited a non-significant improvement in ROM at the arthroplasty segment. The ROM adjacent to the arthroplasty segment was increased, although not significantly, whereas the ROM adjacent to the fusion segment was significantly improved after surgery in both groups (p<.001). Fusion was achieved in all patients. No significant difference in complications was found between the groups. In HS, cephalic or caudal fusion segments to the arthroplasty segment did not affect the clinical outcomes and the behavior of CDA. However, the ROM of adjacent segments was affected by the location of the fusion segment; segments adjacent to fusion segments had greater ROMs than segments adjacent to arthroplasty segments. Copyright © 2018 Elsevier Inc. All rights reserved.

Design and preliminary biomechanical analysis of artificial cervical joint complex.

PubMed

Jian, Yu; Lan-Tao, Liu; Zhao, Jian-ning; Jian-ning, Zhao

2013-06-01

To design an artificial cervical joint complex (ACJC) prosthesis for non-fusion reconstruction after cervical subtotal corpectomy, and to evaluate the biomechanical stability, preservation of segment movements and influence on adjacent inter-vertebral movements of this prosthesis. The prosthesis was composed of three parts: the upper/lower joint head and the middle artificial vertebrae made of Cobalt-Chromium-Molybdenum (Co-Cr-Mo) alloy and polyethylene with a ball-and-socket joint design resembling the multi-axial movement in normal inter-vertebral spaces. Biomechanical tests of intact spine (control), Orion locking plate system and ACJC prosthesis were performed on formalin-fixed cervical spine specimens from 21 healthy cadavers to compare stability, range of motion (ROM) of the surgical segment and ROM of adjacent inter-vertebral spaces. As for stability of the whole lower cervical spine, there was no significant difference of flexion, extension, lateral bending and torsion between intact spine group and ACJC prosthesis group. As for segment movements, difference in flexion, lateral bending or torsion between ACJC prosthesis group and control group was not statistically significant, while ACJC prosthesis group showed an increase in extension (P < 0.05) compared to that of the control group. In addition, ACJC prosthesis group demonstrated better flexion, extension and lateral bending compared to those of Orion plating system group (P < 0.05). Difference in adjacent inter-vertebral ROM of the ACJC prosthesis group was not statistically significant compared to that of the control group. After cervical subtotal corpectomy, reconstruction with ACJC prosthesis not only obtained instant stability, but also reserved segment motions effectively, without abnormal gain of mobility at adjacent inter-vertebral spaces.

A comparison of two non-thrust mobilization techniques applied to the C7 segment in patients with restricted and painful cervical rotation.

PubMed

Creighton, Doug; Gruca, Mark; Marsh, Douglas; Murphy, Nancy

2014-11-01

Cervical mobilization and manipulation have been shown to improve cervical range of motion and pain. Rotatory thrust manipulation applied to the lower cervical segments is associated with controversy and the potential for eliciting adverse reactions (AR). The purpose of this clinical trial was to describe two translatory non-thrust mobilization techniques and evaluate their effect on cervical pain, motion restriction, and whether any adverse effects were reported when applied to the C7 segment. This trial included 30 participants with painful and restricted cervical rotation. Participants were randomly assigned to receive one of the two mobilization techniques. Active cervical rotation and pain intensity measurements were recorded pre- and post-intervention. Within group comparisons were determined using the Wilcoxon signed-rank test and between group comparisons were analyzed using the Mann-Whitney U test. Significance was set at P = 0.05. Thirty participants were evaluated immediately after one of the two mobilization techniques was applied. There was a statistically significant difference (improvement) for active cervical rotation after application of the C7 facet distraction technique for both right (P = 0.022) and left (P = 0.022) rotation. Statistically significant improvement was also found for the C7 facet gliding technique for both right (P = 0.022) and left rotation (P = 0.020). Pain reduction was statistically significant for both right and left rotation after application of both techniques. Both mobilization techniques produced similar positive effects and one was not statistically superior to the other. A single application of both C7 mobilization techniques improved active cervical rotation, reduced perceived pain, and did not produce any AR in 30 patients with neck pain and movement limitation. These two non-thrust techniques may offer clinicians an additional safe and effective manual intervention for patients with limited and painful cervical rotation. A more robust experimental design is recommended to further examine these and similar cervical translatory mobilization techniques.

An improved graph cut segmentation method for cervical lymph nodes on sonograms and its relationship with node's shape assessment.

PubMed

Zhang, Junhua; Wang, Yuanyuan; Shi, Xinling

2009-12-01

A modified graph cut was proposed under the elliptical shape constraint to segment cervical lymph nodes on sonograms, and its effect on the measurement of short axis to long axis ratio (S/L) was investigated by using the relative ultimate measurement accuracy (RUMA). Under the same user inputs, the proposed algorithm successfully segmented all 60 sonograms tested, while the traditional graph cut failed. The mean RUMA resulted from the developed method was comparable to that resulted from the manual segmentation. Results indicated that utilizing the elliptical shape prior could appreciably improve the graph cut for nodes segmentation, and the proposed method satisfied the accuracy requirement of S/L measurement.

A fuzzy optimal threshold technique for medical images

NASA Astrophysics Data System (ADS)

Thirupathi Kannan, Balaji; Krishnasamy, Krishnaveni; Pradeep Kumar Kenny, S.

2012-01-01

A new fuzzy based thresholding method for medical images especially cervical cytology images having blob and mosaic structures is proposed in this paper. Many existing thresholding algorithms may segment either blob or mosaic images but there aren't any single algorithm that can do both. In this paper, an input cervical cytology image is binarized, preprocessed and the pixel value with minimum Fuzzy Gaussian Index is identified as an optimal threshold value and used for segmentation. The proposed technique is tested on various cervical cytology images having blob or mosaic structures, compared with various existing algorithms and proved better than the existing algorithms.

Stabilizing potential of anterior, posterior, and circumferential fixation for multilevel cervical arthrodesis: an in vitro human cadaveric study of the operative and adjacent segment kinematics.

PubMed

Dmitriev, Anton E; Kuklo, Timothy R; Lehman, Ronald A; Rosner, Michael K

2007-03-15

This is an in vitro biomechanical study. The current investigation was performed to evaluate the stabilizing potential of anterior, posterior, and circumferential cervical fixation on operative and adjacent segment motion following 2 and 3-level reconstructions. Previous studies reported increases in adjacent level range of motion (ROM) and intradiscal pressure following single-level cervical arthrodesis; however, no studies have compared adjacent level effects following multilevel anterior versus posterior reconstructions. Ten human cadaveric cervical spines were biomechanically tested using an unconstrained spine simulator under axial rotation, flexion-extension, and lateral bending loading. After intact analysis, all specimens were sequentially instrumented from C3 to C5 with: (1) lateral mass fixation, (2) anterior cervical plate with interbody cages, and (3) combined anterior and posterior fixation. Following biomechanical analysis of 2-level constructs, fixation was extended to C6 and testing repeated. Full ROM was monitored at the operative and adjacent levels, and data normalized to the intact (100%). All reconstructive methods reduced operative level ROM relative to intact specimens under all loading methods (P < 0.05). However, circumferential fixation provided the greatest segmental stability among 2 and 3-level constructs (P < 0.05). Moreover, anterior cervical plate fixation was least efficient at stabilizing operative segments following C3-C6 arthrodesis (P < 0.05). Supradjacent ROM was increased for all treatment groups compared to normal data during flexion-extension testing (P < 0.05). Similar trends were observed under axial rotation and lateral bending loading. At the distal level, flexion-extension and axial rotation testing revealed comparable intergroup differences (P < 0.05), while lateral bending loading indicated greater ROM following 2-level circumferential fixation (P < 0.05). Results from our study revealed greater adjacent level motion following all 3 fixation types. No consistent significant intergroup differences in neighboring segment kinematics were detected among reconstructions. Circumferential fixation provided the greatest level of segmental stability without additional significant increase in adjacent level ROM.

Intra-patient semi-automated segmentation of the cervix-uterus in CT-images for adaptive radiotherapy of cervical cancer

NASA Astrophysics Data System (ADS)

Luiza Bondar, M.; Hoogeman, Mischa; Schillemans, Wilco; Heijmen, Ben

2013-08-01

For online adaptive radiotherapy of cervical cancer, fast and accurate image segmentation is required to facilitate daily treatment adaptation. Our aim was twofold: (1) to test and compare three intra-patient automated segmentation methods for the cervix-uterus structure in CT-images and (2) to improve the segmentation accuracy by including prior knowledge on the daily bladder volume or on the daily coordinates of implanted fiducial markers. The tested methods were: shape deformation (SD) and atlas-based segmentation (ABAS) using two non-rigid registration methods: demons and a hierarchical algorithm. Tests on 102 CT-scans of 13 patients demonstrated that the segmentation accuracy significantly increased by including the bladder volume predicted with a simple 1D model based on a manually defined bladder top. Moreover, manually identified implanted fiducial markers significantly improved the accuracy of the SD method. For patients with large cervix-uterus volume regression, the use of CT-data acquired toward the end of the treatment was required to improve segmentation accuracy. Including prior knowledge, the segmentation results of SD (Dice similarity coefficient 85 ± 6%, error margin 2.2 ± 2.3 mm, average time around 1 min) and of ABAS using hierarchical non-rigid registration (Dice 82 ± 10%, error margin 3.1 ± 2.3 mm, average time around 30 s) support their use for image guided online adaptive radiotherapy of cervical cancer.

Intra-patient semi-automated segmentation of the cervix-uterus in CT-images for adaptive radiotherapy of cervical cancer.

PubMed

Bondar, M Luiza; Hoogeman, Mischa; Schillemans, Wilco; Heijmen, Ben

2013-08-07

For online adaptive radiotherapy of cervical cancer, fast and accurate image segmentation is required to facilitate daily treatment adaptation. Our aim was twofold: (1) to test and compare three intra-patient automated segmentation methods for the cervix-uterus structure in CT-images and (2) to improve the segmentation accuracy by including prior knowledge on the daily bladder volume or on the daily coordinates of implanted fiducial markers. The tested methods were: shape deformation (SD) and atlas-based segmentation (ABAS) using two non-rigid registration methods: demons and a hierarchical algorithm. Tests on 102 CT-scans of 13 patients demonstrated that the segmentation accuracy significantly increased by including the bladder volume predicted with a simple 1D model based on a manually defined bladder top. Moreover, manually identified implanted fiducial markers significantly improved the accuracy of the SD method. For patients with large cervix-uterus volume regression, the use of CT-data acquired toward the end of the treatment was required to improve segmentation accuracy. Including prior knowledge, the segmentation results of SD (Dice similarity coefficient 85 ± 6%, error margin 2.2 ± 2.3 mm, average time around 1 min) and of ABAS using hierarchical non-rigid registration (Dice 82 ± 10%, error margin 3.1 ± 2.3 mm, average time around 30 s) support their use for image guided online adaptive radiotherapy of cervical cancer.

Comparison of Cervical Kinematics, Pain, and Functional Disability Between Single- and Two-level Anterior Cervical Discectomy and Fusion.

PubMed

Chien, Andy; Lai, Dar-Ming; Wang, Shwu-Fen; Hsu, Wei-Li; Cheng, Chih-Hsiu; Wang, Jaw-Lin

2016-08-01

A prospective, time series design. The purpose of this study is two-fold: firstly, to investigate the impact of altered cervical alignment and range of motion (ROM) on patients' self-reported outcomes after anterior cervical discectomy and fusion (ACDF), and secondly, to comparatively differentiate the influence of single- and two-level ACDF on the cervical ROM and adjacent segmental kinematics up to 12-month postoperatively. ACDF is one of the most commonly employed surgical interventions to treat degenerative disc disease. However, there are limited in vivo data on the impact of ACDF on the cervical kinematics and its association with patient-reported clinical outcomes. Sixty-two patients (36 males; 55.63 ± 11.6 yrs) undergoing either a single- or consecutive two-level ACDF were recruited. The clinical outcomes were assessed with the Pain Visual Analogue Scale (VAS) and the Neck Disability Index (NDI). Radiological results included cervical lordosis, global C2-C7 ROM, ROM of the Functional Spinal Unit (FSU), and its adjacent segments. The outcome measures were collected preoperatively and then at 3, 6, and 12-month postoperatively. A significant reduction of both VAS and NDI was found for both groups from the preoperative to 3-month period (P < 0.01). Pearson correlation revealed no significant correlation between global ROM with neither VAS (P = 0.667) nor NDI (P = 0.531). A significant reduction of global ROM was identified for the two-level ACDF group at 12 months (P = 0.017) but not for the single-level group. A significant interaction effect was identified for the upper adjacent segment ROM (P = 0.024) but not at the lower adjacent segment. Current study utilized dynamic radiographs to comparatively evaluate the biomechanical impact of single- and two-level ACDF. The results highlighted that the two-level group demonstrated a greater reduction of global ROM coupled with an increased upper adjacent segmental compensatory motions that is independent of patient-perceived recovery. 3.

Automation-assisted cervical cancer screening in manual liquid-based cytology with hematoxylin and eosin staining.

PubMed

Zhang, Ling; Kong, Hui; Ting Chin, Chien; Liu, Shaoxiong; Fan, Xinmin; Wang, Tianfu; Chen, Siping

2014-03-01

Current automation-assisted technologies for screening cervical cancer mainly rely on automated liquid-based cytology slides with proprietary stain. This is not a cost-efficient approach to be utilized in developing countries. In this article, we propose the first automation-assisted system to screen cervical cancer in manual liquid-based cytology (MLBC) slides with hematoxylin and eosin (H&E) stain, which is inexpensive and more applicable in developing countries. This system consists of three main modules: image acquisition, cell segmentation, and cell classification. First, an autofocusing scheme is proposed to find the global maximum of the focus curve by iteratively comparing image qualities of specific locations. On the autofocused images, the multiway graph cut (GC) is performed globally on the a* channel enhanced image to obtain cytoplasm segmentation. The nuclei, especially abnormal nuclei, are robustly segmented by using GC adaptively and locally. Two concave-based approaches are integrated to split the touching nuclei. To classify the segmented cells, features are selected and preprocessed to improve the sensitivity, and contextual and cytoplasm information are introduced to improve the specificity. Experiments on 26 consecutive image stacks demonstrated that the dynamic autofocusing accuracy was 2.06 μm. On 21 cervical cell images with nonideal imaging condition and pathology, our segmentation method achieved a 93% accuracy for cytoplasm, and a 87.3% F-measure for nuclei, both outperformed state of the art works in terms of accuracy. Additional clinical trials showed that both the sensitivity (88.1%) and the specificity (100%) of our system are satisfyingly high. These results proved the feasibility of automation-assisted cervical cancer screening in MLBC slides with H&E stain, which is highly desirable in community health centers and small hospitals. © 2013 International Society for Advancement of Cytometry.

Vertebra identification using template matching modelmp and K-means clustering.

PubMed

Larhmam, Mohamed Amine; Benjelloun, Mohammed; Mahmoudi, Saïd

2014-03-01

Accurate vertebra detection and segmentation are essential steps for automating the diagnosis of spinal disorders. This study is dedicated to vertebra alignment measurement, the first step in a computer-aided diagnosis tool for cervical spine trauma. Automated vertebral segment alignment determination is a challenging task due to low contrast imaging and noise. A software tool for segmenting vertebrae and detecting subluxations has clinical significance. A robust method was developed and tested for cervical vertebra identification and segmentation that extracts parameters used for vertebra alignment measurement. Our contribution involves a novel combination of a template matching method and an unsupervised clustering algorithm. In this method, we build a geometric vertebra mean model. To achieve vertebra detection, manual selection of the region of interest is performed initially on the input image. Subsequent preprocessing is done to enhance image contrast and detect edges. Candidate vertebra localization is then carried out by using a modified generalized Hough transform (GHT). Next, an adapted cost function is used to compute local voted centers and filter boundary data. Thereafter, a K-means clustering algorithm is applied to obtain clusters distribution corresponding to the targeted vertebrae. These clusters are combined with the vote parameters to detect vertebra centers. Rigid segmentation is then carried out by using GHT parameters. Finally, cervical spine curves are extracted to measure vertebra alignment. The proposed approach was successfully applied to a set of 66 high-resolution X-ray images. Robust detection was achieved in 97.5 % of the 330 tested cervical vertebrae. An automated vertebral identification method was developed and demonstrated to be robust to noise and occlusion. This work presents a first step toward an automated computer-aided diagnosis system for cervical spine trauma detection.

Strain on intervertebral discs after anterior cervical decompression and fusion.

PubMed

Matsunaga, S; Kabayama, S; Yamamoto, T; Yone, K; Sakou, T; Nakanishi, K

1999-04-01

An analysis of the change in strain distribution of intervertebral discs present after anterior cervical decompression and fusion by an original method. The analytical results were compared to occurrence of herniation of the intervertebral disc on magnetic resonance imaging. To elucidate the influence of anterior cervical decompression and fusion on the unfused segments of the spine. There is no consensus regarding the exact significance of the biomechanical change in the unfused segment present after surgery. Ninety-six patients subjected to anterior cervical decompression and fusion for herniation of intervertebral discs were examined. Shear strain and longitudinal strain of intervertebral discs were analyzed on pre- and postoperative lateral dynamic routine radiography of the cervical spine. Thirty of the 96 patients were examined by magnetic resonance imaging before and after surgery, and the relation between alteration in strains and postsurgical occurrence of disc herniation was examined. In the cases of double- or triple-level fusion, shear strain of adjacent segments had increased 20% on average 1 year after surgery. Thirteen intervertebral discs that had an abnormally high degree of strain showed an increase in longitudinal strain after surgery. Eleven (85%) of the 13 discs that showed an abnormal increase in longitudinal strain had herniation in the same intervertebral discs with compression of the spinal cord during the follow-up period. Relief of symptoms was significantly poor in the patients with recent herniation. Close attention should be paid to long-term biomechanical changes in the unfused segment.

A comparative study on dynamic stiffness in typical finite element model and multi-body model of C6-C7 cervical spine segment.

PubMed

Wang, Yawei; Wang, Lizhen; Du, Chengfei; Mo, Zhongjun; Fan, Yubo

2016-06-01

In contrast to numerous researches on static or quasi-static stiffness of cervical spine segments, very few investigations on their dynamic stiffness were published. Currently, scale factors and estimated coefficients were usually used in multi-body models for including viscoelastic properties and damping effects, meanwhile viscoelastic properties of some tissues were unavailable for establishing finite element models. Because dynamic stiffness of cervical spine segments in these models were difficult to validate because of lacking in experimental data, we tried to gain some insights on current modeling methods through studying dynamic stiffness differences between these models. A finite element model and a multi-body model of C6-C7 segment were developed through using available material data and typical modeling technologies. These two models were validated with quasi-static response data of the C6-C7 cervical spine segment. Dynamic stiffness differences were investigated through controlling motions of C6 vertebrae at different rates and then comparing their reaction forces or moments. Validation results showed that both the finite element model and the multi-body model could generate reasonable responses under quasi-static loads, but the finite element segment model exhibited more nonlinear characters. Dynamic response investigations indicated that dynamic stiffness of this finite element model might be underestimated because of the absence of dynamic stiffen effect and damping effects of annulus fibrous, while representation of these effects also need to be improved in current multi-body model. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Proximal Junctional Failure After Long-Segment Instrumentation for Degenerative Lumbar Kyphosis With Ankylosing Spinal Disorder.

PubMed

Ikegami, Daisuke; Matsuoka, Takashi; Miyoshi, Yuji; Murata, Yoichi; Aoki, Yasuaki

2015-06-15

Case report. We report a case of proximal junctional failure at the ankylosed, but not the mobile, junction after segmental instrumented fusion for degenerative lumbar kyphosis with ankylosing spinal disorder. Proximal junctional failure (PJF) and proximal junctional kyphosis (PJK) are important complications that occur subsequent to long-segment instrumentation for correction of adult spinal deformity. Thus far, most studies have focused on the mobile junction as a site at which PJK/PJF can occur, and little is known about the relationship between PJK/PJF and ankylosing spinal disorders such as diffuse idiopathic skeletal hyperostosis. The patient was an 82-year-old female with degenerative lumbar kyphosis. She had abnormal confluent hyperostosis in the anterior longitudinal ligaments from Th5 to Th10. The patient was treated operatively with spinal instrumented fusion from Th10 to the sacrum. Four weeks subsequent to initial surgery, the patient developed progressive lower extremity paresis caused by the uppermost instrumented vertebrae fracture (Th10) and adjacent subluxation (Th9). Extension of fusion to Th5 with decompression at Th9-Th10 was performed. However, the patient showed no improvement in neurological function. PJF can occur at the ankylosing site above the uppermost instrumented vertebrae after long-segment instrumentation for adult spinal deformity. PJF in the ankylosed spine may cause severe fracture instability and cord deficit. The ankylosed spine should be integrated into the objective determination of materials contributing to the appropriate selection of fusion levels. 3.

Fast and Accurate Semi-Automated Segmentation Method of Spinal Cord MR Images at 3T Applied to the Construction of a Cervical Spinal Cord Template

PubMed Central

El Mendili, Mohamed-Mounir; Trunet, Stéphanie; Pélégrini-Issac, Mélanie; Lehéricy, Stéphane; Pradat, Pierre-François; Benali, Habib

2015-01-01

Objective To design a fast and accurate semi-automated segmentation method for spinal cord 3T MR images and to construct a template of the cervical spinal cord. Materials and Methods A semi-automated double threshold-based method (DTbM) was proposed enabling both cross-sectional and volumetric measures from 3D T2-weighted turbo spin echo MR scans of the spinal cord at 3T. Eighty-two healthy subjects, 10 patients with amyotrophic lateral sclerosis, 10 with spinal muscular atrophy and 10 with spinal cord injuries were studied. DTbM was compared with active surface method (ASM), threshold-based method (TbM) and manual outlining (ground truth). Accuracy of segmentations was scored visually by a radiologist in cervical and thoracic cord regions. Accuracy was also quantified at the cervical and thoracic levels as well as at C2 vertebral level. To construct a cervical template from healthy subjects’ images (n=59), a standardization pipeline was designed leading to well-centered straight spinal cord images and accurate probability tissue map. Results Visual scoring showed better performance for DTbM than for ASM. Mean Dice similarity coefficient (DSC) was 95.71% for DTbM and 90.78% for ASM at the cervical level and 94.27% for DTbM and 89.93% for ASM at the thoracic level. Finally, at C2 vertebral level, mean DSC was 97.98% for DTbM compared with 98.02% for TbM and 96.76% for ASM. DTbM showed similar accuracy compared with TbM, but with the advantage of limited manual interaction. Conclusion A semi-automated segmentation method with limited manual intervention was introduced and validated on 3T images, enabling the construction of a cervical spinal cord template. PMID:25816143

Surgical Outcome of a Zero-profile Device Comparing with Stand-alone Cage and Anterior Cervical Plate with Iliac Bone Graft in the Anterior Cervical Discectomy and Fusion

PubMed Central

Shin, Jae Sik; Cho, Pyoung Goo

2014-01-01

Objective A Zero-profile device is a cervical stand-alone cage with integrated segmental fixation device. We characteristically evaluated the radiological changes as well as clinical outcomes in the application of Zero-profile devices compared with stand-alone cages and anterior cervical plates with iliac bone grafts for the cervical disease. Methods Retrospectively, total 60 patients at least more than one year follow-up were enrolled. Twenty patients were treated with Zero-profile devices (Group A), twenty patients with stand-alone cages (Group B) and twenty patients with anterior cervical plates and iliac bone grafts (Group C) for a single level cervical disease. The clinical outcomes were evaluated by Odom's criteria and Bazaz-Yoo dysphagia index. The radiologic parameters were by subsidence and the changes of the midpoint interbody height (IBH), the segmental kyphotic angle (SKA), the overall kyphotic angle (OKA) in index level. Results Although there was no significant clinical difference according to the Odom's criteria among them(p=0.766), post-operative dysphagia was significantly decreased in the Group A and B compared with the Group C (p=0.04). From the immediate postoperative to the last follow-up time, the mean change of IBH decrement and SKA increment were significant in the Group B compared with the Group A (p=0.025, p=0.033) and the Group C (p=0.001, p=0.000). The subsidence rate was not significant among all groups (p=0.338). Conclusion This Zero-profile device is a valuable alternative to the anterior cervical discectomy and fusion with a low incidence of postoperative dysphagia and without segmental kyphotic change. PMID:25346764

Comparison of Curvature Between the Zero-P Spacer and Traditional Cage and Plate After 3-Level Anterior Cervical Discectomy and Fusion: Mid-term Results.

PubMed

Chen, Yuanyuan; Liu, Yang; Chen, Huajiang; Cao, Peng; Yuan, Wen

2017-10-01

A retrospective study. To compare clinical and radiologic outcomes of 3-level anterior cervical discectomy and fusion between a zero-profile (Zero-P) spacer and a traditional plate in cases of symptomatic cervical spine spondylosis. Anterior cervical decompression and fusion is indicated for patients with anterior compression or stenosis of the spinal cord. The Zero-P spacers have been used for anterior cervical interbody fusion of 1 or 2 segments. However, there is a paucity of published clinical data regarding the exact impact of the device on cervical curvature of 3-level fixation. Clinical and radiologic data of 71 patients undergoing 3-level anterior cervical discectomy and fusion from January 2010 to January 2012 were collected. Zero-P spacer was implanted in 33 patients, and in 38 cases stabilization was accomplished using an anterior cervical plate and intervertebral cage. Patients were followed for a mean of 30.8 months (range, 24-36 mo) after surgery. Fusion rates, changes in cervical lordosis, and degeneration of adjacent segments were analyzed. Dysphagia was assessed using the Bazaz score, and clinical outcomes were analyzed using the Neck Disability Index and Japanese Orthopedic Association scoring system. Neurological outcomes did not differ significantly between groups. Significantly less dysphagia was seen at 2- and 6-month follow-up in patients with the Zero-P implant (P<0.05); however, there was significant less cervical lordosis and the lordosis across the fusion in patients with the Zero-P implant (both P<0.05). Degenerative changes in the adjacent segments occurred in 4 patients in the Zero-P group and 6 patients in the standard-plate group (P=0.742); however, no revision surgery was done. Clinical results for the Zero-P spacer were satisfactory. The device is superior to the traditional plate in preventing postoperative dysphagia; however, it is inferior at restoring cervical lordosis. It may not provide better sagittal cervical alignment reconstruction in 3-level fixation. Prospective randomized trials with more patients and longer follow-up periods are required to confirm these observations.

Cervical spinal motion during intubation: efficacy of stabilization maneuvers in the setting of complete segmental instability.

PubMed

Lennarson, P J; Smith, D W; Sawin, P D; Todd, M M; Sato, Y; Traynelis, V C

2001-04-01

The purpose of this study was to characterize and compare segmental cervical motion during orotracheal intubation in cadavers with and without a complete subaxial injury, as well as to examine the efficacy of commonly used stabilization techniques in limiting that motion. Intubation procedures were performed in 10 fresh human cadavers in which cervical spines were intact and following the creation of a complete C4-5 ligamentous injury. Movement of the cervical spine during direct laryngoscopy and intubation was recorded using video fluoroscopy and examined under the following conditions: 1) without stabilization; 2) with manual in-line cervical immobilization; and 3) with Gardner-Wells traction. Subsequently, segmental angular rotation, subluxation, and distraction at the injured C4-5 level were measured from digitized frames of the recorded video fluoroscopy. After complete C4-5 destabilization, the effects of attempted stabilization on distraction, angulation, and subluxation were analyzed. Immobilization effectively eliminated distraction, and diminished angulation, but increased subluxation. Traction significantly increased distraction, but decreased angular rotation and effectively eliminated subluxation. Orotracheal intubation without stabilization had intermediate results, causing less distraction than traction, less subluxation than immobilization, but increased angulation compared with either intervention. These results are discussed in terms of both statistical and clinical significance and recommendations are made.

Cervical anterior hybrid technique with bi-level Bryan artificial disc replacement and adjacent segment fusion for cervical myelopathy over three consecutive segments.

PubMed

Chen, Jiang; Xu, Lin; Jia, Yu-Song; Sun, Qi; Li, Jin-Yu; Zheng, Chen-Ying; Bai, Chun-Xiao; Yu, Qin-Sheng

2016-05-01

This study aimed to assess the preliminary clinical efficacy and feasibility of the hybrid technique for multilevel cervical myelopathy. Considering the many shortcomings of traditional treatment methods for multilevel cervical degenerative myelopathy, hybrid surgery (bi-level Bryan artificial disc [Medtronic Sofamor Danek, Memphis, TN, USA] replacement and anterior cervical discectomy and fusion) should be considered. Between March 2006 and November 2012, 108 patients (68 men and 40 women, average age 45years) underwent hybrid surgery. Based on the Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), and Odom's criteria, the clinical symptoms and neurological function before and after surgery were evaluated. Mean surgery duration was 90minutes, with average blood loss of 30mL. Mean follow-up duration was 36months. At the final follow-up, the mean JOA (± standard deviation) scores were significantly higher compared with preoperative values (15.08±1.47 versus 9.18±1.22; P<0.01); meanwhile, NDI values were markedly decreased (12.32±1.03 versus 42.68±1.83; P<0.01). Using Odom's criteria, the clinical outcomes were rated as excellent (76 patients), good (22 patients), fair (six patients), and poor (four patients). These findings indicate that the hybrid method provides an effective treatment for cervical myelopathy over three consecutive segments, ensuring a good clinical outcome. Copyright © 2015 Elsevier Ltd. All rights reserved.

Segmentation and feature extraction of cervical spine x-ray images

NASA Astrophysics Data System (ADS)

Long, L. Rodney; Thoma, George R.

1999-05-01

As part of an R&D project in mixed text/image database design, the National Library of Medicine has archived a collection of 17,000 digitized x-ray images of the cervical and lumbar spine which were collected as part of the second National Health and Nutrition Examination Survey (NHANES II). To make this image data available and usable to a wide audience, we are investigating techniques for indexing the image content by automated or semi-automated means. Indexing of the images by features of interest to researchers in spine disease and structure requires effective segmentation of the vertebral anatomy. This paper describes work in progress toward this segmentation of the cervical spine images into anatomical components of interest, including anatomical landmarks for vertebral location, and segmentation and identification of individual vertebrae. Our work includes developing a reliable method for automatically fixing an anatomy-based coordinate system in the images, and work to adaptively threshold the images, using methods previously applied by researchers in cardioangiography. We describe the motivation for our work and present our current results in both areas.

Postural Consequences of Cervical Sagittal Imbalance: A Novel Laboratory Model.

PubMed

Patwardhan, Avinash G; Havey, Robert M; Khayatzadeh, Saeed; Muriuki, Muturi G; Voronov, Leonard I; Carandang, Gerard; Nguyen, Ngoc-Lam; Ghanayem, Alexander J; Schuit, Dale; Patel, Alpesh A; Smith, Zachary A; Sears, William

2015-06-01

A biomechanical study using human spine specimens. To study postural compensations in lordosis angles that are necessary to maintain horizontal gaze in the presence of forward head posture and increasing T1 sagittal tilt. Forward head posture relative to the shoulders, assessed radiographically using the horizontal offset distance between the C2 and C7 vertebral bodies (C2-C7 [sagittal vertical alignment] SVA), is a measure of global cervical imbalance. This may result from kyphotic alignment of cervical segments, muscle imbalance, as well as malalignment of thoracolumbar spine. Ten cadaveric cervical spines (occiput-T1) were tested. The T1 vertebra was anchored to a tilting and translating base. The occiput was free to move vertically but its angular orientation was constrained to ensure horizontal gaze regardless of sagittal imbalance. A 5-kg mass was attached to the occiput to mimic head weight. Forward head posture magnitude and T1 tilt were varied and motions of individual vertebrae were measured to calculate C2-C7 SVA and lordosis across C0-C2 and C2-C7. Increasing C2-C7 SVA caused flexion of lower cervical (C2-C7) segments and hyperextension of suboccipital (C0-C1-C2) segments to maintain horizontal gaze. Increasing kyphotic T1 tilt primarily increased lordosis across the C2-C7 segments. Regression models were developed to predict the compensatory C0-C2 and C2-C7 angulation needed to maintain horizontal gaze given values of C2-C7 SVA and T1 tilt. This study established predictive relationships between radiographical measures of forward head posture, T1 tilt, and postural compensations in the cervical lordosis angles needed to maintain horizontal gaze. The laboratory model predicted that normalization of C2-C7 SVA will reduce suboccipital (C0-C2) hyperextension, whereas T1 tilt reduction will reduce the hyperextension in the C2-C7 segments. The predictive relationships may help in planning corrective strategy in patients experiencing neck pain, which may be attributed to sagittal malalignment. N/A.

[Spondylarthrosis of the cervical spine. Therapy].

PubMed

Radl, R; Leixner, G; Stihsen, C; Windhager, R

2013-09-01

Chronic neck pain is often associated with spondylarthrosis, whereby segments C4/C5 (C: cervical) are most frequently affected. Spondylarthrosis can be the sole complaint, but it is associated with a degenerative cascade of the spine. The umbrella term for neck pain is the so-called cervical syndrome, which can be differentiated into segmental dysfunction and/or morphological changes of the intervertebral discs and small joints of the vertebral column. Conservative therapy modalities include physical therapy, subcutaneous application of local anesthetics, muscle, nerve and facet joint injections in addition to adequate analgesic and muscle relaxant therapy. If surgery is required, various techniques via dorsal and ventral approaches, depending on the clinic and morphologic changes, can be applied.

Cadaveric study of movement in the unstable upper cervical spine during emergency management: tracheal intubation and cervical spine immobilisation—a study protocol for a prospective randomised crossover trial

PubMed Central

Popp, Erik; Hüttlin, Petra; Weilbacher, Frank; Münzberg, Matthias; Schneider, Niko; Kreinest, Michael

2017-01-01

Introduction Emergency management of upper cervical spine injuries often requires cervical spine immobilisation and some critical patients also require airway management. The movement of cervical spine created by tracheal intubation and cervical spine immobilisation can potentially exacerbate cervical spinal cord injury. However, the evidence that previous studies have provided remains unclear, due to lack of a direct measurement technique for dural sac's space during dynamic processes. Our study will use myelography method and a wireless human motion tracker to characterise and compare the change of dural sac's space during tracheal intubations and cervical spine immobilisation in the presence of unstable upper cervical spine injury such as atlanto-occipital dislocation or type II odontoid fracture. Methods and analysis Perform laryngoscopy and intubation, video laryngoscope intubation, laryngeal tube insertion, fiberoptic intubation and cervical collar application on cadaveric models of unstable upper cervical spine injury such as atlanto-occipital dislocation or type II odontoid fracture. The change of dural sac's space and the motion of unstable cervical segment are recorded by video fluoroscopy with previously performing myelography, which enables us to directly measure dural sac's space. Simultaneously, the whole cervical spine motion is recorded at a wireless human motion tracker. The maximum dural sac compression and the maximum angulation and distraction of the injured segment are measured by reviewing fluoroscopic and myelography images. Ethics and dissemination This study protocol has been approved by the Ethics Committee of the State Medical Association Rhineland-Palatinate, Mainz, Germany. The results will be published in relevant emergency journals and presented at relevant conferences. Trial registration number DRKS00010499. PMID:28864483

Fractures of the cervical spine

PubMed Central

Marcon, Raphael Martus; Cristante, Alexandre Fogaça; Teixeira, William Jacobsen; Narasaki, Douglas Kenji; Oliveira, Reginaldo Perilo; de Barros Filho, Tarcísio Eloy Pessoa

2013-01-01

OBJECTIVES: The aim of this study was to review the literature on cervical spine fractures. METHODS: The literature on the diagnosis, classification, and treatment of lower and upper cervical fractures and dislocations was reviewed. RESULTS: Fractures of the cervical spine may be present in polytraumatized patients and should be suspected in patients complaining of neck pain. These fractures are more common in men approximately 30 years of age and are most often caused by automobile accidents. The cervical spine is divided into the upper cervical spine (occiput-C2) and the lower cervical spine (C3-C7), according to anatomical differences. Fractures in the upper cervical spine include fractures of the occipital condyle and the atlas, atlanto-axial dislocations, fractures of the odontoid process, and hangman's fractures in the C2 segment. These fractures are characterized based on specific classifications. In the lower cervical spine, fractures follow the same pattern as in other segments of the spine; currently, the most widely used classification is the SLIC (Subaxial Injury Classification), which predicts the prognosis of an injury based on morphology, the integrity of the disc-ligamentous complex, and the patient's neurological status. It is important to correctly classify the fracture to ensure appropriate treatment. Nerve or spinal cord injuries, pseudarthrosis or malunion, and postoperative infection are the main complications of cervical spine fractures. CONCLUSIONS: Fractures of the cervical spine are potentially serious and devastating if not properly treated. Achieving the correct diagnosis and classification of a lesion is the first step toward identifying the most appropriate treatment, which can be either surgical or conservative. PMID:24270959

Cervical Stand-Alone Polyetheretherketone Cage versus Zero-Profile Anchored Spacer in Single-Level Anterior Cervical Discectomy and Fusion : Minimum 2-Year Assessment of Radiographic and Clinical Outcome.

PubMed

Cho, Hyun-Jun; Hur, Junseok W; Lee, Jang-Bo; Han, Jin-Sol; Cho, Tai-Hyoung; Park, Jung-Yul

2015-08-01

We compared the clinical and radiographic outcomes of stand-alone polyetheretherketone (PEEK) cage and Zero-Profile anchored spacer (Zero-P) for single level anterior cervical discectomy and fusion (ACDF). We retrospectively reviewed 121 patients who underwent single level ACDF within 2 years (Jan 2011-Jan 2013) in a single institute. Total 50 patients were included for the analysis who were evaluated more than 2-year follow-up. Twenty-nine patients were allocated to the cage group (m : f=19 : 10) and 21 for Zero-P group (m : f=12 : 9). Clinical (neck disability index, visual analogue scale arm and neck) and radiographic (Cobb angle-segmental and global cervical, disc height, vertebral height) assessments were followed at pre-operative, immediate post-operative, post-3, 6, 12, and 24 month periods. Demographic features and the clinical outcome showed no difference between two groups. The change between final follow-up (24 months) and immediate post-op of Cobb-segmental angle (p=0.027), disc height (p=0.002), vertebral body height (p=0.033) showed statistically better outcome for the Zero-P group than the cage group, respectively. The Zero-Profile anchored spacer has some advantage after cage for maintaining segmental lordosis and lowering subsidence rate after single level anterior cervical discectomy and fusion.

The effect of cervical posterior foraminotomy on segmental range of motion in the setting of total disc arthroplasty.

PubMed

Bevevino, Adam J; Lehman, Ronald A; Kang, Daniel G; Gwinn, David E; Dmitriev, Anton E

2014-09-01

Human cadaveric biomechanical analysis. To investigate the effect on cervical spine segmental stability that results from a posterior foraminotomy after cervical disc arthroplasty (CDA). Posterior foraminotomy offers the ability to decompress cervical nerves roots while avoiding the need to extend a previous fusion or revise an arthroplasty to a fusion. However, the safety of a foraminotomy in the setting of CDA is unknown. Segmental nondestructive range of motion (ROM) was analyzed in 9 human cadaveric cervical spine specimens. After intact testing, each specimen was sequentially tested according to the following 4 experimental groups: group 1=C5-C6 CDA, group 2=C5-C6 CDA with unilateral C5-C6 foraminotomy, group 3=C5-C6 CDA with bilateral C5-C6 foraminotomy, and group 4=C5-C6 CDA with C5-C6 and C4-C5 bilateral foraminotomy. No differences in ROM were found between the intact, CDA, and foraminotomy specimens at C4-C5 or C6-C7. There was a step-wise increase in C5-C6 axial rotation from the intact state (8°) to group 4 (12°), although the difference did not reach statistical significance. At C5-C6, the degree of lateral bending remained relatively constant. Flexion and extension at C5-C6 was significantly higher in the foraminotomy specimens, groups 2 (18.1°), 3 (18.6°), and 4 (18.2°), compared with the intact state, 11.2°. However, no ROM difference was found within foraminotomy groups (2-4) or between the foraminotomy groups and the CDA group (group 1), 15.3°. Our results indicate that cervical stability is not significantly decreased by the presence, number, or level of posterior foraminotomies in the setting of CDA. The addition of foraminotomies to specimens with a pre-existing CDA resulted in small and insignificant increases in segmental ROM. Therefore, biomechanically, posterior foraminotomy/foraminotomies may be considered a safe and viable option in the setting of recurrent or adjacent level radiculopathy after cervical disc replacement. N/A.

Fusion-nonfusion hybrid construct versus anterior cervical hybrid decompression and fusion: a comparative study for 3-level cervical degenerative disc diseases.

PubMed

Ding, Fan; Jia, Zhiwei; Wu, Yaohong; Li, Chao; He, Qing; Ruan, Dike

2014-11-01

A retrospective analysis. This study aimed to compare the safety and efficacy between the fusion-nonfusion hybrid construct (HC: anterior cervical corpectomy and fusion plus artificial disc replacement, ACCF plus cADR) and anterior cervical hybrid decompression and fusion (ACHDF: anterior cervical corpectomy and fusion plus discectomy and fusion, ACCF plus ACDF) for 3-level cervical degenerative disc diseases (cDDD). The optimal anterior technique for 3-level cDDD remains uncertain. Long-segment fusion substantially induced biomechanical changes at adjacent levels, which may lead to symptomatic adjacent segment degeneration. Hybrid surgery consisting of ACDF and cADR has been reported with good results for 2-level cDDD. In this context, ACCF combining with cADR may be an alternative to ACHDF for 3-level cDDD. Between 2009 and 2012, 28 patients with 3-level cDDD who underwent HC (n=13) and ACHDF (15) were retrospectively reviewed. Clinical assessments were based on Neck Disability Index, Japanese Orthopedic Association disability scale, visual analogue scale, Japanese Orthopedic Association recovery rate, and Odom criteria. Radiological analysis included range of motion of C2-C7 and adjacent segments and cervical lordosis. Perioperative parameters, radiological adjacent-level changes, and the complications were also assessed. HC showed better Neck Disability Index improvement at 12 and 24 months, as well as Japanese Orthopedic Association and visual analogue scale improvement at 24 months postoperatively (P<0.05). HC had better outcome according to Odom criteria but not significantly (P>0.05). The range of motion of C2-C7 and adjacent segments was less compromised in HC (P<0.05). Both 2 groups showed significant lordosis recovery postoperatively (P<0.05), but no difference was found between groups (P>0.05). The incidence of adjacent-level degenerative changes and complications was higher in ACHDF but not significantly (P>0.05). HC may be an alternative to ACHDF for 3-level cDDD due to the equivalent or superior early clinical outcomes, less compromised C2-C7 range of motion, and less impact at adjacent levels. 3.

Do Postoperative Biomechanical Changes Induce Heterotopic Ossification After Cervical Arthroplasty?: A 5-Year Follow-up Study.

PubMed

Kim, Keun Su; Heo, Dong Hwa

2016-07-01

Prospective clinical study. To evaluate the factors that would predispose a patient to heterotopic ossification (HO) formation after cervical arthroplasty. HO after arthroplasty is one of the complications of cervical total disk replacement (TDR). However, the predisposing factors and pathophysiology of HO have not been precisely described. We prospectively enrolled and followed up 23 patients, who received single-level arthroplasty with ProDisc-C, for 5 years after the operation. The patients who developed grade 3 or 4 HO were classified into the "high-grade HO group," whereas the patients with grade 0, 1, or 2 HO were classified into the "low-grade HO group." We compared the postoperative changes in the range of motion (ROM) and height of the functional segmental unit (FSU) of the implantation segments between the 2 groups. The mean differences in height and ROM of the FSU were 2.59±1.42 mm and 6.7±3.2 degrees in the high-grade HO group, and 0.87±0.72 mm and 3.1±2.8 degrees in the low-grade HO group. The mean differences in height and ROM of the FSU were significantly higher in the high-grade HO group than in the low-grade HO group (P<0.05). After cervical arthroplasty, the height of the FSU and ROM of the implantation segments were significantly increased in the high-grade HO group compared with the low-grade HO group. Overcorrection of the height of the FSU and increase in the ROM of the implantation segment may influence the formation of HOs after cervical arthroplasty.

Comparison of Anterior Cervical Discectomy and Fusion versus Posterior Cervical Foraminotomy in the Treatment of Cervical Radiculopathy: A Systematic Review.

PubMed

Liu, Wei-Jun; Hu, Ling; Chou, Po-Hsin; Wang, Jun-Wen; Kan, Wu-Sheng

2016-11-01

Controversy remains over whether anterior cervical discectomy and fusion (ACDF) or posterior cervical foraminotomy (PCF) is superior for the treatment of cervical radiculopathy. We therefore performed a systematic review including three prospective randomized controlled trails (RCT) and seven retrospective comparative studies (RCoS) by searching PubMed and EMBASE. These studies were assessed on risk of bias according to the Cochrane Handbook for Systematic Reviews of Interventions, and the quality of evidence and level of recommendation were evaluated according to the GRADE approach. Clinical outcomes, complications, reoperation rates, radiological parameters, and cost/cost-utility were evaluated. The mean complication rate was 7% in the ACDF group and 4% in the PCF group, and the mean reoperation rate was 4% in the ACDF group and 6% in the PCF group within 2 years of the initial surgery. There was a strong level of recommendation that no difference existed in clinical outcome, complication rate and reoperation rate between the ACDF and the PCF group. There was conflicting evidence that the ACDF group had better clinical outcomes than the PCF group (one study with weak level of recommendation). PCF could preserve the range of motion (ROM) of the operated segment but did not increase the ROM of the adjacent segment (weak level of recommendation). Meanwhile, the average cost or cost-utility of the PCF group was significantly lower than that of the ACDF group (weak level of recommendation). In conclusion, the PCF was just as safe and effective as the ACDF in the treatment of cervical radiculopathy. Meanwhile, PCF might have lower medical cost than ACDF and decrease the incidence of adjacent segment disease. Based on the available evidence, PCF appears to be another good surgical approach in the treatment of cervical radiculopathy. © 2016 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

Prospective, Randomized Comparison of One-level Mobi-C Cervical Total Disc Replacement vs. Anterior Cervical Discectomy and Fusion: Results at 5-year Follow-up

PubMed Central

Zigler, Jack E.; Jackson, Robert; Nunley, Pierce D.; Bae, Hyun W.; Kim, Kee D.; Ohnmeiss, Donna D.

2016-01-01

Introduction There is increasing interest in the role of cervical total disc replacement (TDR) as an alternative to anterior cervical discectomy and fusion (ACDF). Multiple prospective randomized studies with minimum 2 year follow-up have shown TDR to be at least as safe and effective as ACDF in treating symptomatic degenerative disc disease at a single level. The purpose of this study was to compare outcomes of cervical TDR using the Mobi-C® with ACDF at 5-year follow-up. Methods This prospective, randomized, controlled trial was conducted as a Food and Drug Administration regulated Investigational Device Exemption trial across 23 centers with 245 patients randomized (2:1) to receive TDR with Mobi-C® Cervical Disc Prosthesis or ACDF with anterior plate and allograft. Outcome assessments included a composite overall success score, Neck Disability Index (NDI), visual analog scales (VAS) assessing neck and arm pain, Short Form-12 (SF-12) health survey, patient satisfaction, major complications, subsequent surgery, segmental range of motion, and adjacent segment degeneration. Results The 60-month follow-up rate was 85.5% for the TDR group and 78.9% for the ACDF group. The composite overall success was 61.9% with TDR vs. 52.2% with ACDF, demonstrating statistical non-inferiority. Improvements in NDI, VAS neck and arm pain, and SF-12 scores were similar between groups and were maintained from earlier follow-up through 60 months. There was no significant difference between TDR and ACDF in adverse events or major complications. Range of motion was maintained with TDR through 60 months. Device-related subsequent surgeries (TDR: 3.0%, ACDF: 11.1%, p<0.02) and adjacent segment degeneration at the superior level (TDR: 37.1%, ACDF: 54.7%, p<0.03) were significantly lower for TDR patients. Conclusions Five-year results demonstrate the safety and efficacy of TDR with the Mobi-C as a viable alternative to ACDF with the potential advantage of lower rates of reoperation and adjacent segment degeneration, in the treatment of one-level symptomatic cervical degenerative disc disease. Clinical Relevance This prospective, randomized study with 5-year follow-up adds to the existing literature indicating that cervical TDR is a viable alternative to ACDF in appropriately selected patients. Level of Evidence This is a Level I study. PMID:27162712

Localized cervical facet joint kinematics under physiological and whiplash loading.

PubMed

Stemper, Brian D; Yoganandan, Narayan; Gennarelli, Thomas A; Pintar, Frank A

2005-12-01

Although facet joints have been implicated in the whiplash injury mechanism, no investigators have determined the degree to which joint motions in whiplash are nonphysiological. The purpose of this investigation was to quantify the correlation between facet joint and segmental motions under physiological and whiplash loading. Human cadaveric cervical spine specimens were exercise tested under physiological extension loading, and intact human head-neck complexes were exercise tested under whiplash loading to correlate the localized component motions of the C4-5 facet joint with segmental extension. Facet joint shear and distraction kinematics demonstrated a linear correlation with segmental extension under both loading modes. Facet joints responded differently to whiplash and physiological loading, with significantly increased kinematics for the same-segmental angulation. The limitations of this study include removal of superficial musculature and the limited sample size for physiological testing. The presence of increased facet joint motions indicated that synovial joint soft-tissue components (that is, synovial membrane and capsular ligament) sustain increased distortion that may subject these tissues to a greater likelihood of injury. This finding is supported by clinical investigations in which lower cervical facet joint injury resulted in similar pain patterns due to the most commonly reported whiplash symptoms.

Adjacent segment degeneration and disease following cervical arthroplasty: a systematic review and meta-analysis.

PubMed

Shriver, Michael F; Lubelski, Daniel; Sharma, Akshay M; Steinmetz, Michael P; Benzel, Edward C; Mroz, Thomas E

2016-02-01

Cervical arthroplasty is an increasingly popular alternative for the treatment of cervical radiculopathy and myelopathy. This technique preserves motion at the index and adjacent disc levels, avoiding the restraints of fusion and potentially minimizing adjacent segment pathology onset during the postoperative period. This study aimed to identify all prospective studies reporting adjacent segment pathology rates for cervical arthroplasty. Systematic review and meta-analysis were carried out. Studies reporting adjacent segment degeneration (ASDegeneration) and adjacent segment disease (ASDisease) rates in patients who underwent cervical arthroplasty comprised the patient sample. Outcomes of interest included reported ASDegeneration and ASDisease events after cervical arthroplasty. We conducted a MEDLINE, SCOPUS, and Web of Science search for studies reporting ASDegeneration or ASDisease following cervical arthroplasty. A meta-analysis was performed to calculate effect summary values, 95% confidence intervals (CIs), Q values, and I(2) values. Forest plots were constructed for each analysis group. Of the 1,891 retrieved articles, 32 met inclusion criteria. The patient incidence of ASDegeneration and ASDisease was 8.3% (95% CI 3.8%-12.7%) and 0.9% (95% CI 0.1%-1.7%), respectively. The rate of ASDegeneration and ASDisease at individual levels was 10.5% (95% CI 6.1%-14.9%) and 0.2% (95% CI -0.1% to 0.5%), respectively. Studies following patients for 12-24 months reported a 5.1% (95% CI 2.1%-8.1%) incidence of ASDegeneration and 0.2% (95% CI 0.1%-0.2%) incidence of ASDisease. Conversely, studies following patients for greater than 24 months reported a 16.6% (5.8%-27.4%) incidence of ASDegeneration and 2.6% (95% CI 1.0%-4.2%) of ASDisease. This identified a statistically significant increase in ASDisease diagnosis with lengthier follow-up. Additionally, 1- and 2-level procedures resulted in a 7.4% (95% CI 3.3%-11.4%) and15.6% (95 CI-9.2% to 40.4%) incidence of ASDegeneration, respectively. Although there was an 8.2% increase in ASDegeneration following 2-level operations (relative to 1-level), it did not reach statistical significance. We were unable to analyze ASDisease incidence following 2-level arthroplasty (too few cases), but 1-level operations resulted in an ASDisease incidence of 0.8% (95% CI 0.1%-1.5%). This review represents a comprehensive estimation of the actual incidence of ASDegeneration and ASDisease across a heterogeneous group of surgeons, patients, and arthroplasty techniques. Our investigation should serve as a framework for individual surgeons to understand the impact of various cervical arthroplasty techniques, follow-up duration, and surgical levels on the incidence of ASDegeneration and ASDisease during the postoperative period. Copyright © 2015 Elsevier Inc. All rights reserved.

[Application of a stand-alone interbody fusion cage based on a novel porous TiO2/glass composite. I. Implantation in the sheep cervical spine and radiological evaluation].

PubMed

Korinth, M C; Hero, T; Mahnken, A H; Ragoss, C; Scherer, K

2004-12-01

Animals are becoming more and more common as in vitro and in vivo models for the human spine. Especially the sheep cervical spine is stated to be of good comparability and usefulness in the evaluation of in vivo radiological, biomechanical and histological behaviour of new bone replacement materials, implants and cages for cervical spine interbody fusion. In preceding biomechanical in vitro examination human cervical spine specimens were tested after fusion with either a cubical stand-alone interbody fusion cage manufactured from a new porous TiO/glass composite (Ecopore) or polymethyl-methacrylate (PMMA) after discectomy. First experience with the use of the new material and its influence on the primary stability after in vitro application were gained. After fusion of 10 sheep cervical spines in the levels C2/3 and C4/5 in each case with PMMA and with an Ecopore-cage, radiologic as well as computertomographic examinations were performed postoperatively and every 4 weeks during the following 2 and 4 months, respectively. Apart from establishing our animal model, we analysed the radiological changes and the degree of bony fusion of the operated segments during the course. In addition we performed measurements of the corresponding disc space heights (DSH) and intervertebral angles (IVA) for comparison among each other, during the course and with the initial values. Immediately after placement of both implants in the disc spaces the mean DSH and IVA increased (34.8% and 53.9%, respectively). During the following months DSH decreased to a greater extent in the Ecopore-segments than in the PMMA-segments, even to a value below the initial value (p>0.05). Similarly, the IVA decreased in both groups in the postoperative time lapse, but more distinct in the Ecopore-segments (p<0.05). These changes in terms of a subsidence of the implants, were confirmed morphologically in the radiological examination in the course. The radiologically evaluated fusion, i.e. bony bridging of the operated segments, was more pronounced after implantation of an Ecopore-cage (83%), than after PMMA interposition (50%), but did not gain statistical significance. In this first in vivo examination of our new porous ceramic bone replacement material we showed its application in the spondylodesis model of the sheep cervical spine. Distinct radiological changes regarding evident subsidence and detectable fusion of the segments, operated on with the new biomaterial, were seen. We demonstrated the radiological changes of the fused segments during several months and analysed them morphologically, before the biomechanical evaluation will be presented in a subsequent publication.

Magnetic resonance imaging evaluation of adjacent segments after cervical disc arthroplasty: magnet strength and its effect on image quality. Clinical article.

PubMed

Antosh, Ivan J; DeVine, John G; Carpenter, Clyde T; Woebkenberg, Brian J; Yoest, Stephen M

2010-12-01

Disc arthroplasty is an alternative to fusion following anterior discectomy when treating either cervical radiculopathy or myelopathy. Its theoretical benefits include preservation of the motion segment and the potential prevention of adjacent-segment degeneration. There is a paucity of data regarding the ability to use MR imaging to evaluate the adjacent segments. The purpose of this study was for the authors to introduce open MR imaging as an alternative method in imaging adjacent segments following cervical disc arthroplasty using a Co-Cr implant and to report their preliminary results using this technique. Postoperative cervical MR images were obtained in the first 16 patients in whom the porous coated motion (PCM-V) cervical arthroplasty system was used to treat a single level between C-3 and C-7. Imaging was performed in all 16 patients with a closed 1.5-T unit, and in the final 6 patients it was also performed with an open 0.2-T unit. All images were evaluated by an independent radiologist observer for the ability to visualize the superior endplate, disc space, and inferior endplate at the superior and inferior adjacent levels. Utilizing the 1.5-T magnet to assess the superior adjacent level, the superior endplate, disc space, and inferior endplate could each be visualized less than 50% of the time on sagittal T1- and sagittal and axial T2-weighted images. Similarly, the inferior adjacent level structures were adequately visualized less than 50% of the time, with the exception of slightly improved visualization of the inferior endplate on T1-weighted images (56%). Axial images allowed worse visualization than sagittal images at both the superior and inferior adjacent levels. Utilizing the 0.2-T magnet to assess the superior and inferior adjacent levels, the superior endplate, disc space, and inferior endplate were adequately visualized in 100% of images. Based on the results of this case series, it appears that the strength of the magnet affects the artifact from the Co-Cr endplates. The open 0.2-T MR imaging unit reduces artifact at adjacent levels after cervical disc arthroplasty without a significant reduction in the image quality. Magnetic resonance imaging can be used to evaluate the adjacent segments after disc arthroplasty if magnet strength is addressed, providing another means to assess the long-term efficacy of this novel treatment.

Symptomatic adjacent segment disease after cervical total disc replacement: re-examining the clinical and radiological evidence with established criteria.

PubMed

Nunley, Pierce D; Jawahar, Ajay; Cavanaugh, David A; Gordon, Charles R; Kerr, Eubulus J; Utter, Phillip Andrew

2013-01-01

Although several publications in the last decade have proved equality in safety and efficacy of the total disc replacement (TDR) to the anterior fusion procedure in cervical spine, the claim that TDR may reduce the incidence of adjacent segment disease (ASD) has not been corroborated by clinical evidence. We attempt to predict the true incidence of symptomatic ASD after TDR surgery in the cervical spine at one or two levels at a median follow-up period of 4 years. A total of 763 patients were screened to participate in four different Food and Drug Administration device exemption trials for artificial cervical disc replacement at three collaborating institutions. Two hundred seventy-one patients qualified and enrolled in the trials. One hundred seventy-three randomized to receive artificial disc replacement surgery, and 167 have completed a 4-year or longer follow-up. Patients experiencing cervical radiculopathy symptoms in the follow-up period were worked-up with clinical examinations, magnetic resonance imaging of the cervical spine, and other diagnostic studies. Once a clinical correlation was established with the imaging evidence of adjacent segment degeneration, a careful record was maintained to document the subsequent medical and/or surgical treatment received by these patients. Statistical analysis was performed to determine the true incidence of and factors affecting the ASD after cervical disc replacement in these patients. Twenty-six patients (15.2%) were identified to satisfy our criteria for ASD at the median follow-up of 51 months, with the annual incidence of 3.1% as calculated by life tables. The actuarial 5-year freedom from ASD rate was 71.6%±0.6%, and the mean period for freedom from ASD was 70.4±2.1 months. The incidence of symptomatic ASD after cervical TDR is 3.1% annually regardless of the patient's age, sex, smoking habits, and design of the TDR device. The presence of osteopenia and lumbar degenerative disease significantly increase the risk of developing ASD after anterior cervical surgery. Copyright © 2013 Elsevier Inc. All rights reserved.

Segmentation of nuclear images in automated cervical cancer screening

NASA Astrophysics Data System (ADS)

Dadeshidze, Vladimir; Olsson, Lars J.; Domanik, Richard A.

1995-08-01

This paper describes an efficient method of segmenting cell nuclei from complex scenes based upon the use of adaptive region growing in conjuction with nucleus-specific filters. Results of segmenting potentially abnormal (cancer or neoplastic) cell nuclei in Papanicolaou smears from 0.8 square micrometers resolution images are also presented.

DeepPap: Deep Convolutional Networks for Cervical Cell Classification.

PubMed

Zhang, Ling; Le Lu; Nogues, Isabella; Summers, Ronald M; Liu, Shaoxiong; Yao, Jianhua

2017-11-01

Automation-assisted cervical screening via Pap smear or liquid-based cytology (LBC) is a highly effective cell imaging based cancer detection tool, where cells are partitioned into "abnormal" and "normal" categories. However, the success of most traditional classification methods relies on the presence of accurate cell segmentations. Despite sixty years of research in this field, accurate segmentation remains a challenge in the presence of cell clusters and pathologies. Moreover, previous classification methods are only built upon the extraction of hand-crafted features, such as morphology and texture. This paper addresses these limitations by proposing a method to directly classify cervical cells-without prior segmentation-based on deep features, using convolutional neural networks (ConvNets). First, the ConvNet is pretrained on a natural image dataset. It is subsequently fine-tuned on a cervical cell dataset consisting of adaptively resampled image patches coarsely centered on the nuclei. In the testing phase, aggregation is used to average the prediction scores of a similar set of image patches. The proposed method is evaluated on both Pap smear and LBC datasets. Results show that our method outperforms previous algorithms in classification accuracy (98.3%), area under the curve (0.99) values, and especially specificity (98.3%), when applied to the Herlev benchmark Pap smear dataset and evaluated using five-fold cross validation. Similar superior performances are also achieved on the HEMLBC (H&E stained manual LBC) dataset. Our method is promising for the development of automation-assisted reading systems in primary cervical screening.

Standalone Anterior Cervical Discectomy and Fusion Versus Combination with Foraminotomy for the Treatment of Cervical Spondylotic Radiculopathy Secondary to Bony Foraminal Stenosis.

PubMed

Guo, Qunfeng; Wang, Liang; Zhang, Bangke; Jiang, Jiayao; Guo, Xiang; Lu, Xuhua; Ni, Bin

2016-11-01

To compare the results of anterior cervical discectomy and fusion (ACDF) combined with anterior cervical foraminotomy (ACF) and standalone ACDF for the treatment of cervical spondylotic radiculopathy (CSR). The data of 24 consecutive patients who underwent ACDF combined with ACF for significant bony foraminal stenosis were reviewed. The clinical outcomes, including visual analog scale (VAS) scores for neck pain and arm pain and Neck Disability Index, were evaluated by questionnaires. Radiologic outcomes as manifested by C2-7 angle and surgical segmental angle were recorded. The outcomes were compared with outcomes of standalone ACDF for CSR secondary to posterolateral spurs. At the final follow-up evaluation, all patients obtained bone fusion. No patient developed adjacent segment disease. Operative time was longer and blood loss was more in the ACDF combined with ACF group than in the ACDF group (all P < 0.05). However, in both groups, the neck VAS score, arm VAS score, and Neck Disability Index were significantly reduced postoperatively (all P < 0.05). The segmental curve and C2-7 lordosis were significantly improved postoperatively (all P < 0.05). There was no significant difference between the 2 groups in clinical and radiologic outcomes (P > 0.05). For CSR with foraminal stenosis secondary to significant bony pathology that cannot be managed with standalone ACDF, ACDF combined with ACF is an effective and safe treatment strategy. Copyright © 2016 Elsevier Inc. All rights reserved.

Simultaneous Nonrigid Registration, Segmentation, and Tumor Detection in MRI Guided Cervical Cancer Radiation Therapy

PubMed Central

Lu, Chao; Chelikani, Sudhakar; Jaffray, David A.; Milosevic, Michael F.; Staib, Lawrence H.; Duncan, James S.

2013-01-01

External beam radiation therapy (EBRT) for the treatment of cancer enables accurate placement of radiation dose on the cancerous region. However, the deformation of soft tissue during the course of treatment, such as in cervical cancer, presents significant challenges for the delineation of the target volume and other structures of interest. Furthermore, the presence and regression of pathologies such as tumors may violate registration constraints and cause registration errors. In this paper, automatic segmentation, nonrigid registration and tumor detection in cervical magnetic resonance (MR) data are addressed simultaneously using a unified Bayesian framework. The proposed novel method can generate a tumor probability map while progressively identifying the boundary of an organ of interest based on the achieved nonrigid transformation. The method is able to handle the challenges of significant tumor regression and its effect on surrounding tissues. The new method was compared to various currently existing algorithms on a set of 36 MR data from six patients, each patient has six T2-weighted MR cervical images. The results show that the proposed approach achieves an accuracy comparable to manual segmentation and it significantly outperforms the existing registration algorithms. In addition, the tumor detection result generated by the proposed method has a high agreement with manual delineation by a qualified clinician. PMID:22328178

Measurement of intervertebral cervical motion by means of dynamic x-ray image processing and data interpolation.

PubMed

Bifulco, Paolo; Cesarelli, Mario; Romano, Maria; Fratini, Antonio; Sansone, Mario

2013-01-01

Accurate measurement of intervertebral kinematics of the cervical spine can support the diagnosis of widespread diseases related to neck pain, such as chronic whiplash dysfunction, arthritis, and segmental degeneration. The natural inaccessibility of the spine, its complex anatomy, and the small range of motion only permit concise measurement in vivo. Low dose X-ray fluoroscopy allows time-continuous screening of cervical spine during patient's spontaneous motion. To obtain accurate motion measurements, each vertebra was tracked by means of image processing along a sequence of radiographic images. To obtain a time-continuous representation of motion and to reduce noise in the experimental data, smoothing spline interpolation was used. Estimation of intervertebral motion for cervical segments was obtained by processing patient's fluoroscopic sequence; intervertebral angle and displacement and the instantaneous centre of rotation were computed. The RMS value of fitting errors resulted in about 0.2 degree for rotation and 0.2 mm for displacements.

Prospective, Randomized Comparison of Cervical Total Disk Replacement Versus Anterior Cervical Fusion: Results at 48 Months Follow-up.

PubMed

Hisey, Michael S; Bae, Hyun W; Davis, Reginald J; Gaede, Steven; Hoffman, Greg; Kim, Kee D; Nunley, Pierce D; Peterson, Daniel; Rashbaum, Ralph F; Stokes, John; Ohnmeiss, Donna D

2015-05-01

This was a prospective, randomized, controlled multicenter trial. The purpose of this study was to compare clinical outcomes at 4-year follow-up of patients receiving cervical total disk replacement (TDR) with those receiving anterior cervical discectomy and fusion (ACDF). ACDF has been the traditional treatment for symptomatic disk degeneration. Several studies found single-level TDR to be as safe and effective as ACDF at ≥2 years follow-up. Patients from 23 centers were randomized in a 2:1 ratio with 164 receiving the investigational device (Mobi-C Cervical Disc Prosthesis) and 81 receiving ACDF using an anterior plate and allograft. Patients were evaluated preoperatively and 6 weeks, 3, 6, 12, 18, 24, 36, and 48 months postoperatively. Outcome assessments included a composite success score, Neck Disability Index, visual analog scales assessing neck and arm pain, patient satisfaction, major complications, subsequent surgery, segmental range of motion, and adjacent-segment degeneration. The composite success rate was similar in the 2 groups at 48-month follow-up. Mean Neck Disability Index, visual analog scale, and SF-12 scores were significantly improved in early follow-up in both groups with improvements maintained throughout 48 months. On some measures, TDR had significantly greater improvement during early follow-up. At no follow-up were TDR scores significantly worse than ACDF scores. Subsequent surgery rate was significantly higher for ACDF compared with TDR (9.9% vs. 3.0%, P<0.05). Range of motion was maintained with TDR having a mean baseline value of 8 degrees compared with 10 degrees at 48 months. The incidence of adjacent-segment degeneration was significantly higher with ACDF at inferior and superior segments compared with TDR (inferior: 50% vs. 30%, P<0.025; superior: 53% vs. 34%, P<0.025). Significant improvements were observed in pain and function. TDR patients maintained motion and had significantly lower rates of reoperation and adjacent-segment degeneration compared with ACDF. This study supports the safety and efficacy of TDR in appropriately selected patients.

Segmental kyphosis after cervical interbody fusion with stand-alone polyetheretherketone (PEEK) cages: a comparative study on 2 different PEEK cages.

PubMed

Kim, Chi Heon; Chung, Chun Kee; Jahng, Tae-Ahn; Park, Sung Bae; Sohn, Seil; Lee, Sungjoon

2015-02-01

Retrospective comparative study. Two polyetheretherketone (PEEK) cages of different designs were compared in terms of the postoperative segmental kyphosis after anterior cervical discectomy and fusion. Segmental kyphosis occasionally occurs after the use of a stand-alone cage for anterior cervical discectomy and fusion. Although PEEK material seems to have less risk of segmental kyphosis compared with other materials, the occurrence of segmental kyphosis for PEEK cages has been reported to be from 0% to 29%. There have been a few reports that addressed the issue of PEEK cage design. A total of 41 consecutive patients who underwent single-level anterior discectomy and fusion with a stand-alone cage were included. Either a round tube-type (Solis; 18 patients, S-group) or a trapezoidal tube-type (MC+; 23 patients, M-group) cage was used. The contact area between the cage and the vertebral body is larger in MC+ than in Solis, and anchoring pins were present in the Solis cage. The effect of the cage type on the segmental angle (SA) (lordosis vs. kyphosis) at postoperative month 24 was analyzed. Preoperatively, segmental lordosis was present in 12/18 S-group and 16/23 M-group patients (P=0.84). The SA was more lordotic than the preoperative angle in both groups just after surgery, with no difference between groups (P=0.39). At 24 months, segmental lordosis was observed in 9/18 S-group and 20/23 M-group patients (P=0.01). The patients in M-group were 7.83 times more likely than patients in S-group (P=0.04; odds ratio, 7.83; 95% confidence interval, 1.09-56.28) not to develop segmental kyphosis. The design of the PEEK cage used may influence the SA, and this association needs to be considered when using stand-alone PEEK cages.

Disc replacement adjacent to cervical fusion: a biomechanical comparison of hybrid construct versus two-level fusion.

PubMed

Lee, Michael J; Dumonski, Mark; Phillips, Frank M; Voronov, Leonard I; Renner, Susan M; Carandang, Gerard; Havey, Robert M; Patwardhan, Avinash G

2011-11-01

A cadaveric biomechanical study. To investigate the biomechanical behavior of the cervical spine after cervical total disc replacement (TDR) adjacent to a fusion as compared to a two-level fusion. There are concerns regarding the biomechanical effects of cervical fusion on the mobile motion segments. Although previous biomechanical studies have demonstrated that cervical disc replacement normalizes adjacent segment motion, there is a little information regarding the function of a cervical disc replacement adjacent to an anterior cervical decompression and fusion, a potentially common clinical application. Nine cadaveric cervical spines (C3-T1, age: 60.2 ± 3.5 years) were tested under load- and displacement-control testing. After intact testing, a simulated fusion was performed at C4-C5, followed by C6-C7. The simulated fusion was then reversed, and the response of TDR at C5-C6 was measured. A hybrid construct was then tested with the TDR either below or above a single-level fusion and contrasted with a simulated two-level fusion (C4-C6 and C5-C7). The external fixator device used to simulate fusion significantly reduced range of motion (ROM) at C4-C5 and C6-C7 by 74.7 ± 8.1% and 78.1 ± 11.5%, respectively (P < 0.05). Removal of the fusion construct restored the motion response of the spinal segments to their intact state. Arthroplasty performed at C5-C6 using the porous-coated motion disc prosthesis maintained the total flexion-extension ROM to the level of the intact controls when used as a stand-alone procedure or when implanted adjacent to a single-level fusion (P > 0.05). The location of the single-level fusion, whether above or below the arthroplasty, did not significantly affect the motion response of the arthroplasty in the hybrid construct. Performing a two-level fusion significantly increased the motion demands on the nonoperated segments as compared to a hybrid TDR-plus fusion construct when the spine was required to reach the same motion end points. The spine with a hybrid construct required significantly less extension moment than the spine with a two-level fusion to reach the same extension end point. The porous-coated motion cervical prosthesis restored the ROM of the treated level to the intact state. When the porous-coated motion prosthesis was used in a hybrid construct, the TDR response was not adversely affected. A hybrid construct seems to offer significant biomechanical advantages over two-level fusion in terms of reducing compensatory adjacent-level hypermobility and also loads required to achieve a predetermined ROM.

Posterior Multilevel Instrumentation of the Lower Cervical Spine: Is Bridging the Cervicothoracic Junction Necessary?

PubMed

Osterhoff, Georg; Ryang, Yu-Mi; von Oelhafen, Judith; Meyer, Bernhard; Ringel, Florian

2017-07-01

Multisegmental cervical instrumentations ending at the cervicothoracic junction may lead to significant adjacent segment degeneration. The purpose of this study was to compare the extent of sequential pathologies in the lower adjacent segment between patient groups with a primarily cervical instrumentation ending at C7 versus an instrumentation including the cervicothoracic junction ending at T1 or T2. A retrospective analysis of 98 consecutive patients with multisegmental posterior cervical fusion surgery ending either at C7 or at T1 or T2 was performed. Radiographic parameters of degeneration at the adjacent segment below the instrumentation were determined postoperatively and at follow-up (FU), and the need for secondary interventions was documented. A total of 74 patients had a FU of at least 6 months (C7: n = 58, age 63 ± 11 years, FU 36 ± 26 months; T1/T2: n = 16, age 65 ± 13 years, FU 37 ± 21 months). There were no significant differences between the C7 and T1/T2 groups with regard to the change in kyphosis angle (P = 0.162), disc height (P = 0.204), or disc degeneration according to the Mimura grading system (P = 0.718). Secondary interventions due to adjacent segmental pathology or implant failure were necessary in 18 of 58 (31%) of the C7 cases and in 1 of 16 (6.3%) of the T1/T2 cases (P = 0.038). Patients with multisegmental posterior cervical fusions ending at C7 showed a greater rate of clinically symptomatic pathologies at the adjacent level below the instrumentation. On the basis of our data and with its limitations in mind, one may consider to bridge the cervicothoracic junction and to end the instrumentation at T1 or T2 in those cases. Copyright © 2017 Elsevier Inc. All rights reserved.

The fascicular anatomy and peak force capabilities of the sternocleidomastoid muscle.

PubMed

Kennedy, Ewan; Albert, Michael; Nicholson, Helen

2017-06-01

The fascicular morphology of the sternocleidomastoid (SCM) is not well described in modern anatomical texts, and the biomechanical forces it exerts on individual cervical motion segments are not known. The purpose of this study is to investigate the fascicular anatomy and peak force capabilities of the SCM combining traditional dissection and modern imaging. This study is comprised of three parts: Dissection, magnetic resonance imaging (MRI) and biomechanical modelling. Dissection was performed on six embalmed cadavers: three males of age 73-74 years and three females of age 63-93 years. The fascicular arrangement and morphologic data were recorded. MRIs were performed on six young, healthy volunteers: three males of age 24-37 and three females of age 26-28. In vivo volumes of the SCM were calculated using the Cavalieri method. Modelling of the SCM was performed on five sets of computed tomography (CT) scans. This mapped the fascicular arrangement of the SCM with relation to the cervical motion segments, and used volume data from the MRIs to calculate realistic peak force capabilities. Dissection showed the SCM has four parts; sterno-mastoid, sterno-occipital, cleido-mastoid and cleido-occipital portions. Force modelling shows that peak torque capacity of the SCM is higher at lower cervical levels, and minimal at higher levels. Peak shear forces are higher in the lower cervical spine, while compression is consistent throughout. The four-part SCM is capable of producing forces that vary across the cervical motion segments. The implications of these findings are discussed with reference to models of neck muscle function and dysfunction.

Effect of Unifocal versus Multifocal Lenses on Cervical Spine Posture in Patients with Presbyopia.

PubMed

Abbas, Rami L; Houri, Mohamad T; Rayyan, Mohammad M; Hamada, Hamada Ahmad; Saab, Ibtissam M

2018-04-04

There are many environmental considerations which may or may not lead to the development of faulty cervical mechanics. The design of near vision lenses could contribute to the development of such cervical dysfunction and consequently neck pain. Decision making regarding proper type of lens prescription seems important for presbyopic individuals. To investigate the effect of unifocal and multifocal lenses on cervical posture. Thirty subjects (18 females and 12 males) participated in the study with an age range from 40 to 64 years. Each subject wore consequently both unifocal and multifocal lenses randomly while reading. Then lateral cervical spine X-ray films were taken for each subject during each lens wearing. X-ray films were analyzed with digital software (Autocad software, 2 D) to measure segmental angles of the cervical vertebrae (Occiput/C1, C1/C2, C2/C3, C3/C4, C4/C5, C5/C6, C6/C7, C3/C7, C0/C3, and occiput/C7). Higher significant extension angle in the segments C0/C7, C1/C2, C5/C6, C6/C7, and C3/C7 (p<0.05) during multifocal lenses wearing were observed in contrast with higher flexion angle between C3/C4 and C4/C5 (p<0.05) with unifocal lenses wear. Multifocal lens spectacles produces increased extension in the cervical vertebrae angles when compared with the use of unifocal lenses.

Severe fixed cervical kyphosis treated with circumferential osteotomy and pedicle screw fixation using an anterior-posterior-anterior surgical sequence.

PubMed

Yoshihara, Hiroyuki; Abumi, Kuniyoshi; Ito, Manabu; Kotani, Yoshihisa; Sudo, Hideki; Takahata, Masahiko

2013-11-01

Surgical treatment for severe circumferentially fixed cervical kyphosis has been challenging. Both anterior and posterior releases are necessary to provide the cervical mobility necessary for fusion in a corrected position. In two case reports, we describe the circumferential osteotomy of anterior-posterior-anterior surgical sequence, and the efficacy of this technique when cervical pedicle screw fixation for severe fixed cervical kyphosis is used. Etiology of fixed cervical kyphosis was unknown in one patient and neurofibromatosis in one patient. Both patients had severe fixed cervical kyphosis as determined by cervical radiographs and underwent circumferential osteotomy and fixation via an anterior-posterior-anterior surgical sequence and correction of kyphosis by pedicle screw fixation. Severe fixed cervical kyphosis was treated successfully by the use of circumferential osteotomy and pedicle screw fixation. The surgical sequence described in this report is a reasonable approach for severe circumferentially fixed cervical kyphosis and short segment fixation can be achieved using pedicle screws. Copyright © 2013 Elsevier Inc. All rights reserved.

Comparison of segmental spinal movement control in adolescents with and without idiopathic scoliosis using modified pressure biofeedback unit.

PubMed

Luo, Hong-Ji; Lin, Shi-Xiang; Wu, Shyi-Kuen; Tsai, Mei-Wun; Lee, Shwn-Jen

2017-01-01

Postural rehabilitation emphasizing on motor control training of segmental spinal movements has been proposed to effectively reduce the scoliotic spinal deformities in adolescent idiopathic scoliosis (AIS). However, information regarding the impairments of segmental spinal movement control involving segmental spinal stabilizers in adolescent idiopathic scoliosis remains limited. Examination of segmental spinal movement control may provide a window for investigating the features of impaired movement control specific to spinal segments that may assist in the development of physiotherapeutic management of AIS. To compare segmental spinal movement control in adolescents with and without idiopathic scoliosis using modified pressure biofeedback unit. Segmental spinal movement control was assessed in twenty adolescents with idiopathic scoliosis (AISG) and twenty healthy adolescents (CG) using a modified pressure biofeedback unit. Participants performed segmental spinal movements that primarily involved segmental spinal stabilizing muscles with graded and sustained muscle contraction against/off a pressure cuff from baseline to target pressures and then maintained for 1 min. Pressure data during the 1-minute maintenance phase were collected for further analysis. Pressure deviation were calculated and compared between groups. The AISG had significantly greater pressure deviations for all segmental spinal movements of cervical, thoracic, and lumbar spine than the CG. Pressure biofeedback unit was feasible for assessing segmental spinal movement control in AIS. AISG exhibited poorer ability to grade and sustain muscle activities for local movements of cervical, thoracic, and lumbar spine, suggesting motor control training of segmental spinal movements involving segmental spinal stabilizing muscles on frontal, sagittal, and transverse planes were required.

Comparison of cervical spine kinematics using a fluoroscopic model for adjacent segment degeneration. Invited submission from the Joint Section on Disorders of the Spine and Peripheral Nerves, March 2007.

PubMed

Cheng, Joseph S; Liu, Fei; Komistek, Richard D; Mahfouz, Mohamed R; Sharma, Adrija; Glaser, Diana

2007-11-01

In this cervical spine kinematics study the authors evaluate the motions and forces in the normal, degenerative, and fused states to assess how alteration in the cervical motion segment affects adjacent segment degeneration and spondylosis. Fluoroscopic images obtained in 30 individuals (10 in each group with disease at C5-6) undergoing flexion/extension motions were collected. Kinematic data were obtained from the fluoroscopic images and analyzed with an inverse dynamic mathematical model of the cervical spine that was developed for this analysis. During 20 degrees flexion to 15 degrees extension, average relative angles at the adjacent levels of C6-7 and C4-5 in the fused patients were 13.4 degrees and 8.8 degrees versus 3.7 degrees and 4.8 degrees in the healthy individuals. Differences at C3-4 averaged only about 1 degrees. Maximum transverse forces in the fused spines were two times the skull weight at C6-7 and one times the skull weight at C4-5, compared with 0.2 times the skull weight and 0.3 times the skull weight in the healthy individuals. Vertical forces ranged from 1.6 to 2.6 times the skull weight at C6-7 and from 1.2 to 2.5 times the skull weight at C4-5 in the patients who had undergone fusion, and from 1.4 to 3.1 times the skull weight and from 0.9 to 3.3 times the skull weight, respectively, in the volunteers. Adjacent-segment degeneration may occur in patients with fusion due to increased motions and forces at both adjacent levels when compared with healthy individuals in a comparable flexion and extension range.

Motion Path of the Instant Center of Rotation in the Cervical Spine During In Vivo Dynamic Flexion-Extension: Implications for Artificial Disc Design and Evaluation of Motion Quality Following Arthrodesis

PubMed Central

Anderst, William; Baillargeon, Emma; Donaldson, William; Lee, Joon; Kang, James

2013-01-01

Study Design Case-control. Objective To characterize the motion path of the instant center of rotation (ICR) at each cervical motion segment from C2 to C7 during dynamic flexion-extension in asymptomatic subjects. To compare asymptomatic and single-level arthrodesis patient ICR paths. Summary of Background Data The ICR has been proposed as an alternative to range of motion (ROM) for evaluating the quality of spine movement and for identifying abnormal midrange kinematics. The motion path of the ICR during dynamic motion has not been reported. Methods 20 asymptomatic controls, 12 C5/C6 and 5 C6/C7 arthrodesis patients performed full ROM flexion-extension while biplane radiographs were collected at 30 Hz. A previously validated tracking process determined three-dimensional vertebral position with sub-millimeter accuracy. The finite helical axis method was used to calculate the ICR between adjacent vertebrae. A linear mixed-model analysis identified differences in the ICR path among motion segments and between controls and arthrodesis patients. Results From C2/C3 to C6/C7, the mean ICR location moved superior for each successive motion segment (p < .001). The AP change in ICR location per degree of flexion-extension decreased from the C2/C3 motion segment to the C6/C7 motion segment (p < .001). Asymptomatic subject variability (95% CI) in the ICR location averaged ±1.2 mm in the SI direction and ±1.9 mm in the AP direction over all motion segments and flexion-extension angles. Asymptomatic and arthrodesis groups were not significantly different in terms of average ICR position (all p ≥ .091) or in terms of the change in ICR location per degree of flexion-extension (all p ≥ .249). Conclusions To replicate asymptomatic in vivo cervical motion, disc replacements should account for level-specific differences in the location and motion path of ICR. Single-level anterior arthrodesis does not appear to affect cervical motion quality during flexion-extension. PMID:23429677

[Analysis of the results of total cervical disc arthroplasty using a M6-C prosthesis: a multicenter study].

PubMed

Byval'tsev, V A; Kalinin, A A; Stepanov, I A; Pestryakov, Yu Ya; Shepelev, V V

Cervical spondylosis and intervertebral disc (IVD) degeneration are the most common cause for compression of the spinal cord and/or its roots. Total IVD arthroplasty, as a modern alternative to surgical treatment of IVD degeneration, is gaining popularity in many neurosurgical clinics around the world. Aim - the study aim was to conduct a multicenter analysis of cervical spine arthroplasty with an IVD prosthesis M6-C ('Spinal Kinetics', USA). The study included 112 patients (77 males and 35 females). All patients underwent single-level discectomy with implantation of the artificial IVD prosthesis M6-C. The follow-up period was up to 36 months. Dynamic assessment of the prosthesis was based on clinical parameters (pain intensity in the cervical spine and upper extremities (visual analog scale - VAS); quality of life (Neck Disability Index - NDI)); and subjective satisfaction with the results of surgical treatment (Macnab scale) and instrumental data (range of motion in the operated spinal motion segment, degree of heterotopic ossification (McAfee-Suchomel classification), and time course of degenerative changes in the adjacent segments).

Analysis of progression of cervical OPLL using computerized tomography: typical sign of maturation of OPLL mass.

PubMed

Choi, Byung-Wan; Baek, Dong-Hoon; Sheffler, Lindsey C; Chang, Han

2015-07-17

OBJECT The progression of cervical ossification of the posterior longitudinal ligament (OPLL) can lead to increase in the size of the OPLL mass and aggravation of neurological symptoms. In the present study, the authors aimed to analyze the progression of cervical OPLL by using CT imaging, elucidate the morphology of OPLL masses, and evaluate the factors associated with the progression of cervical OPLL. METHODS Sixty patients with cervical OPLL were included. All underwent an initial CT examination and had at least 24 months' follow-up with CT. The mean duration of follow-up was 29.6 months. Fourteen patients (Group A) had CT evidence of OPLL progression, and 46 (Group B) did not show evidence of progression on CT. The 2 groups were compared with respect to the following variables: sex, age, number of involved segments, type of OPLL, and treatment methods. The CT findings, such as the connection of an OPLL mass with the vertebral body and formation of trabeculation in the mass, were evaluated. RESULTS Sex and treatment modality were not associated with OPLL progression. The mean age of the patients in Group A was significantly lower than that in Group B (p = 0.03). The mean number of involved segments was 5.3 in Group A and 3.6 in Group B (p = 0.002). Group A had a higher proportion of cases with the mixed type of OPLL, whereas Group B had a higher proportion of cases with the segmental type (p = 0.02). A connection between the vertebral body and OPLL mass and trabeculation formation were more common in Group B (p < 0.01). CONCLUSIONS Progression of cervical OPLL is associated with younger age, involvement of multiple levels, and mixed-type morphology. OPLL masses that are contiguous with the vertebral body and have trabecular formation are useful findings for identifying masses that are less likely to progress.

Biomechanics of Hybrid Anterior Cervical Fusion and Artificial Disc Replacement in 3-Level Constructs: An In Vitro Investigation

PubMed Central

Liao, Zhenhua; Fogel, Guy R.; Pu, Ting; Gu, Hongsheng; Liu, Weiqiang

2015-01-01

Background The ideal surgical approach for cervical disk disease remains controversial, especially for multilevel cervical disease. The purpose of this study was to investigate the biomechanics of the cervical spine after 3-level hybrid surgery compared with 3-level anterior cervical discectomy and fusion (ACDF). Material/Methods Eighteen human cadaveric spines (C2-T1) were evaluated under displacement-input protocol. After intact testing, a simulated hybrid construct or fusion construct was created between C3 to C6 and tested in the following 3 conditions: 3-level disc plate disc (3DPD), 3-level plate disc plate (3PDP), and 3-level plate (3P). Results Compared to intact, almost 65~80% of motion was successfully restricted at C3-C6 fusion levels (p<0.05). 3DPD construct resulted in slight increase at the 3 instrumented levels (p>0.05). 3PDP construct resulted in significant decrease of ROM at C3-C6 levels less than 3P (p<0.05). Both 3DPD and 3PDP caused significant reduction of ROM at the arthrodesis level and produced motion increase at the arthroplasty level. For adjacent levels, 3P resulted in markedly increased contribution of both upper and lower adjacent levels (p<0.05). Significant motion increases lower than 3P were only noted at partly adjacent levels in some conditions for 3DPD and 3PDP (p<0.05). Conclusions ACDF eliminated motion within the construct and greatly increased adjacent motion. Artificial cervical disc replacement normalized motion of its segment and adjacent segments. While hybrid conditions failed to restore normal motion within the construct, they significantly normalized motion in adjacent segments compared with the 3-level ACDF condition. The artificial disc in 3-level constructs has biomechanical advantages compared to fusion in normalizing motion. PMID:26529430

Preoperative spinal cord damage affects the characteristics and prognosis of segmental motor paralysis after cervical decompression surgery.

PubMed

Ikegami, Shota; Tsutsumimoto, Takahiro; Ohta, Hiroshi; Yui, Mutsuki; Kosaku, Hidemi; Uehara, Masashi; Misawa, Hiromichi

2014-03-15

Retrospective analysis. To test the hypothesis that preoperative spinal cord damage affects postoperative segmental motor paralysis (SMP). SMP is an enigmatic complication after cervical decompression surgery. The cause of this complication remains controversial. We particularly focused on preoperative T2-weighted high signal change (T2HSC) on magnetic resonance imaging in the spinal cord, and assessed the influence of preoperative T2HSC on SMP after cervical decompression surgery. A retrospective review of 181 consecutive patients (130 males and 51 females) who underwent cervical decompression surgery was conducted. SMP was defined as development of postoperative motor palsy of the upper extremities by at least 1 grade in manual muscle testing without impairment of the lower extremities. The relationship between the locations of T2HSC in preoperative magnetic resonance imaging and SMP and Japanese Orthopedic Association score was investigated. Preoperative T2HSC was detected in 78% (142/181) of the patients. SMP occurred in 9% (17/181) of the patients. Preoperative T2HSC was not a significant risk factor for the occurrence of SMP (P = 0.682). However, T2HSC significantly influenced the severity of SMP: the number of paralyzed segments increased with an incidence rate ratio of 2.2 (P = 0.026), the manual muscle score deteriorated with an odds ratio of 8.4 (P = 0.032), and the recovery period was extended with a hazard ratio of 4.0 (P = 0.035). In patients with preoperative T2HSC, Japanese Orthopaedic Association scores remained lower than those in patients without T2HSC throughout the entire period including pre- and postoperative periods (P < 0.001). Preoperative T2HSC was associated with worse severity of SMP in patients who underwent cervical decompression surgery, suggesting that preoperative spinal cord damage is one of the pathomechanisms of SMP after cervical decompression surgery. 3.

Biomechanics of Hybrid Anterior Cervical Fusion and Artificial Disc Replacement in 3-Level Constructs: An In Vitro Investigation.

PubMed

Liao, Zhenhua; Fogel, Guy R; Pu, Ting; Gu, Hongsheng; Liu, Weiqiang

2015-11-03

The ideal surgical approach for cervical disk disease remains controversial, especially for multilevel cervical disease. The purpose of this study was to investigate the biomechanics of the cervical spine after 3-level hybrid surgery compared with 3-level anterior cervical discectomy and fusion (ACDF). Eighteen human cadaveric spines (C2-T1) were evaluated under displacement-input protocol. After intact testing, a simulated hybrid construct or fusion construct was created between C3 to C6 and tested in the following 3 conditions: 3-level disc plate disc (3DPD), 3-level plate disc plate (3PDP), and 3-level plate (3P). Compared to intact, almost 65~80% of motion was successfully restricted at C3-C6 fusion levels (p<0.05). 3DPD construct resulted in slight increase at the 3 instrumented levels (p>0.05). 3PDP construct resulted in significant decrease of ROM at C3-C6 levels less than 3P (p<0.05). Both 3DPD and 3PDP caused significant reduction of ROM at the arthrodesis level and produced motion increase at the arthroplasty level. For adjacent levels, 3P resulted in markedly increased contribution of both upper and lower adjacent levels (p<0.05). Significant motion increases lower than 3P were only noted at partly adjacent levels in some conditions for 3DPD and 3PDP (p<0.05). ACDF eliminated motion within the construct and greatly increased adjacent motion. Artificial cervical disc replacement normalized motion of its segment and adjacent segments. While hybrid conditions failed to restore normal motion within the construct, they significantly normalized motion in adjacent segments compared with the 3-level ACDF condition. The artificial disc in 3-level constructs has biomechanical advantages compared to fusion in normalizing motion.

The biomechanical effect of transverse connectors use in a pre- and postlaminectomy model of the posterior cervical spine: an in vitro cadaveric study.

PubMed

Majid, Kamran; Gudipally, Manasa; Hussain, Mir; Moldavsky, Mark; Khalil, Saif

2011-12-15

An in vitro biomechanical study investigating the effect of transverse connectors on posterior cervical stabilization system in a laminectomy model. To evaluate the optimal design, number, and location of the transverse connectors in stabilizing long segment posterior instrumentation in the cervical spine. In the cervical spine, lateral mass screw (LMS) fixation is used for providing stability after decompression. Transverse connectors have been used to augment segmental posterior instrumentation. However, in the cervical region the optimal design, number, and the location of transverse connectors is not known. Seven fresh human cervicothoracic cadaveric spines (C2-T1) were tested by applying ±1.5 Nm moments in flexion (F), extension (E), lateral bending (LB), and axial rotation (AR). After testing the intact condition, LMS/rods were placed and then were tested with two different transverse connectors (top-loading connector [TL] and the head-to-head [HH] connector) in multiple levels, pre- and postlaminectomy (PL). LMS significantly reduced segmental motion by 77.2% in F, 75.6% in E, 86.6% in LB, and 86.1% in AR prelaminectomy and by 75.4% in F, 76% in E, 80.6% in LB, and 76.4% in AR postlaminectomy compared to intact (P < 0.05). Only in AR, PL constructs with HH connectors at C3 & C7, TL connectors at C4-C5 & C5-C6, and at C3-C4 & C6-C7 significantly reduced the range of motion by 12.9%, 11.9%, and 11.9%, respectively, compared to PL LMS (P < 0.05). No statistical significance was observed between TL connector and HH connector in all loading directions. The biomechanical advantage of transverse connectors is significant in AR, when using two connectors at the proximal and distal ends, compared to one connector. In a clinical setting, this data may guide surgeons on transverse connector configurations to consider during posterior cervical instrumentation.

Ultrasound-based coordinate measuring system for estimating cervical dysfunction during functional movement.

PubMed

Hemmati, Nima; Abolhassani, Mohammad Djavad; Forghani, Arash

2008-01-01

Cervical range of motion (ROM) is a part of the dynamic component of spine evaluation and can be used as an indication of dysfunction in anatomical structures as well as a diagnostic aid in patients with neck pain. Studies indicate that movement coordination of axial segments such as head in dynamic state, disrupted in pathologic conditions. In recent years, a number of non-invasive instruments with varying degrees of accuracy and repeatability have been utilized to measure active or passive range of motion in asymptomatic adults. The aim of this investigation is to design and implement a new method by evidence based approach for estimating the level of defect in segment stability and improvement after treatment by measuring quality or quantity of movement among cervical segment. Transmitter sensors which have been mounted on body send ultrasonic burst signal periodically and from the delay time it takes for this burst to reach three other sensors which arranged on a T-shape Mechanical base, three dimensional position of the transmitter can be calculated. After sending 3D coordination data to a PC via USB port, a complex and elaborative Visual Basic software calculate the angular dispersion and acceleration for each segment separately. This software also calculates the stabilization parameters such as anchoring index (AI) and cross-correlation function (CCF) between head and trunk.

Hybrid Corpectomy and Disc Arthroplasty for Cervical Spondylotic Myelopathy Caused by Ossification of Posterior Longitudinal Ligament and Disc Herniation.

PubMed

Chang, Huang-Chou; Tu, Tsung-Hsi; Chang, Hsuan-Kan; Wu, Jau-Ching; Fay, Li-Yu; Chang, Peng-Yuan; Wu, Ching-Lan; Huang, Wen-Cheng; Cheng, Henrich

2016-11-01

The combination of anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) has been demonstrated to be effective for multilevel cervical spondylotic myelopathy (CSM); however, the combination of ACCF and cervical disc arthroplasty (CDA) for 3-level CSM has never been addressed. Consecutive patients (>18 years of age) with CSM caused by segmental ossification of posterior longitudinal ligament (OPLL) and degenerative disc disease (DDD) were reviewed. Inclusion criteria were patients who underwent hybrid ACCF and CDA surgery for symptomatic 3-level CSM with OPLL and DDD. Medical and radiologic records were reviewed retrospectively. A total of 15 patients were analyzed with a mean follow-up of 18.1 ± 7.42 months. Every patient had hybrid surgery composed of 1-level ACCF (for segmental-type OPLL causing spinal stenosis) and 1-level CDA at the adjacent level (for DDD causing stenosis). All clinical outcomes, including visual analogue scale of neck and arm pain, Neck Disability Index, Japanese Orthopedic Association scores, and Nurick scores of myelopathy, demonstrated significant improvement at 12 months after surgery. All patients (100%) achieved arthrodesis for the ACCF (instrumented) and preserved mobility for CDA (preoperation 6.2 ± 3.81° vs. postoperation 7.0 ± 4.18°; P = 0.579). For patients with multilevel CSM caused by segmental OPLL and DDD, the hybrid surgery of ACCF and CDA demonstrated satisfactory clinical and radiologic outcomes. Moreover, although located next to each other, the instrumented ACCF construct and CDA still achieved solid arthrodesis and preserved mobility, respectively. Therefore, hybrid surgery may be a reasonable option for the management of CSM with OPLL. Copyright © 2016 Elsevier Inc. All rights reserved.

Composite cervical skin and cartilage flap provides a novel large airway substitute after long-segment tracheal resection.

PubMed

Fabre, Dominique; Singhal, Sunil; De Montpreville, Vincent; Decante, Benoit; Mussot, Sacha; Chataigner, Olivier; Mercier, Olaf; Kolb, Frederic; Dartevelle, Philippe G; Fadel, Elie

2009-07-01

Airway replacement after long-segment tracheal resection for benign and malignant disease remains a challenging problem because of the lack of a substitute conduit. Ideally, an airway substitute should be well vascularized, rigid, and autologous to avoid infections, airway stenosis, and the need for immunosuppression. We report the development of an autologous tracheal substitute for long-segment tracheal resection that satisfies these criteria and demonstrates excellent short-term functional results in a large-animal study. Twelve adult pigs underwent long-segment (6 cm, 60% of total length) tracheal resection. Autologous costal cartilage strips measuring 6 cm x 2 mm were harvested from the chest wall and inserted at regular 0.5-cm intervals between dermal layers of a cervical skin flap. The neotrachea was then scaffolded by rotating the composite cartilage skin flap around a silicone stent measuring 6 cm in length and 1.4 cm in diameter. The neotrachea replaced the long segment of tracheal resection, and the donor flap site was closed with a double-Z plasty. Animals were killed at 1 week (group I, n = 4), 2 weeks (group II, n = 4), and 5 weeks (group III, n = 4). In group III the stent was removed 1 week before death. Viability of the neotrachea was monitored by means of daily flexible bronchoscopy and histologic examination at autopsy. Long-term morbidity and mortality were determined by monitoring weight gain, respiratory distress, and survival. There was no mortality during the study period. Weight gain was appropriate in all animals. Daily bronchoscopy and postmortem histologic evaluation confirmed excellent viability of the neotrachea. There was no evidence of suture-line dehiscence. Five animals had distal granulomas that were removed by using rigid bronchoscopy. In group III 1 animal had tracheomalacia, which was successfully managed by means of insertion of a silicon stent. Airway reconstruction with autologous cervical skin flaps scaffolded with costal cartilages is a novel approach to replace long segments of resected trachea. This preliminary study demonstrates excellent respiratory function and survival in large animals undergoing resection of more than 50% of their native trachea. Use of cervical skin flaps buttressed with costal cartilage is a promising solution for long-segment tracheal replacement.

Correlation between cervical lordosis and adjacent segment pathology after anterior cervical spinal surgery.

PubMed

Lee, Soo Eon; Jahng, Tae-Ahn; Kim, Hyun Jib

2015-12-01

To evaluate the incidence and risk factors for adjacent segment pathology (ASP) after anterior cervical spinal surgery. Fourteen patients (12 male, mean age 47.1 years) who underwent single-level cervical disk arthroplasty (CDA group) and 28 case-matched patients (24 male, mean age 53.6 years) who underwent single-level anterior cervical discectomy and fusion (ACDF group) were included. Presence of radiologic ASP (RASP) was based on observed changes in anterior osteophytes, disks, and calcification of the anterior longitudinal ligament on lateral radiographs. The mean follow-up period was 43.4 months in the CDA group and 44.6 months in the ACDF group. At final follow-up, ASP was observed in 5 (35.7%) CDA patients and 16 (57.1%) ACDF patients (p = 0.272). The interval between surgery and ASP development was 33.8 months in the CDA group and 16.3 months in the ACDF group (p = 0.046). The ASP risk factor analysis indicated postoperative cervical angle at C3-7 being more lordotic in non-ASP patients in both groups. Restoration of lordosis occurred in the CDA group regardless of the presence of ASP, but heterotopic ossification development was associated with the presence of ASP in the CDA group. And the CDA group had significantly greater clinical improvements than those in the ACDF group when ASP was present. In both CDA and ACDF patients, RASP developed, but CDA was associated with a delay in ASP development. A good clinical outcome was expected in CDA group, even when ASP developed. Restoration of cervical lordosis was an important factor in anterior cervical spine surgery.

Implementation of mass media community health education: the Forsyth County Cervical Cancer Prevention Project.

PubMed

Dignan, M; Bahnson, J; Sharp, P; Beal, P; Smith, M; Michielutte, R

1991-09-01

The Forsyth County Cervical Cancer Prevention Project (FCP) is a community-based health education project funded by the National Cancer Institute. The target population includes around 25 000 black women age 18 and older who reside in Forsyth County, North Carolina. The overall goal of the program is to prevent mortality from cervical cancer by promoting Pap smears and return for follow-up care when needed. Based on the principles of social marketing, a plan to reach the target population with mass media educational messages through electronic and print channels was developed. Guided by marketing objectives, the target population was divided into relatively discrete segments. The segments included church attenders, patients in waiting rooms of public and selected health providers, female students at local colleges, shoppers, viewers of radio and television, newspaper readers, and business owners and managers. Introduction of the program was based on strategies developed for reaching the target population in each segment with television, radio and print mass media messages. Qualitative assessment of the mass media developed by the program indicated that all forms of communication helped to increase awareness of the program.

Development and validation of a 10-year-old child ligamentous cervical spine finite element model.

PubMed

Dong, Liqiang; Li, Guangyao; Mao, Haojie; Marek, Stanley; Yang, King H

2013-12-01

Although a number of finite element (FE) adult cervical spine models have been developed to understand the injury mechanisms of the neck in automotive related crash scenarios, there have been fewer efforts to develop a child neck model. In this study, a 10-year-old ligamentous cervical spine FE model was developed for application in the improvement of pediatric safety related to motor vehicle crashes. The model geometry was obtained from medical scans and meshed using a multi-block approach. Appropriate properties based on review of literature in conjunction with scaling were assigned to different parts of the model. Child tensile force-deformation data in three segments, Occipital-C2 (C0-C2), C4-C5 and C6-C7, were used to validate the cervical spine model and predict failure forces and displacements. Design of computer experiments was performed to determine failure properties for intervertebral discs and ligaments needed to set up the FE model. The model-predicted ultimate displacements and forces were within the experimental range. The cervical spine FE model was validated in flexion and extension against the child experimental data in three segments, C0-C2, C4-C5 and C6-C7. Other model predictions were found to be consistent with the experimental responses scaled from adult data. The whole cervical spine model was also validated in tension, flexion and extension against the child experimental data. This study provided methods for developing a child ligamentous cervical spine FE model and to predict soft tissue failures in tension.

Phosphorylation of spinal signaling-regulated kinases by acute uterine cervical distension in rats.

PubMed

Wang, L Z; Liu, X; Wu, W X; Chai, R K; Chang, X Y

2010-01-01

Spinal extracellular signaling-regulated kinase 1 and 2 (ERK 1/2) have been found to contribute to nociceptive processing, but the role of spinal ERK 1/2 in visceral pain related to the uterine cervix, the source of pain during the first stage of labor, is unknown. The aim of this study was to investigate ERK activation (phosphorylation) in spinal dorsal horn neurons after acute uterine cervical distension. Under intraperitoneal anesthesia using chloral hydrate 300 mg/kg, female Sprague-Dawley rats were exposed to a 10-s uterine cervical distension of 25, 50, 75, and 100g or no distension (sham). The electromyographic response in the rectus abdominis muscle and mean arterial blood pressure and heart rate changes to uterine cervical distension were determined. The numbers of phosphorylated-ERK 1/2- immunoreactive (pERK 1/2-IR) dorsal horn neurons in cervical (C5-8), thoracic (T5-8), thoracolumbar (T12-L2) and lumbosacral (L(6)-S(1)) segments were counted using immunohistochemistry. Compared with the non-distended sham rats, uterine cervical distension resulted in a stimulus-dependent increase in electromyographic activity and the number of pERK-IR neurons that selectively located to the thoracolumbar segment, mostly in the deep dorsal and the central canal regions. The time course study demonstrated that spinal ERK activation peaked at 60 min with a slow decline for 120 min after uterine cervical distension stimulation. This study suggests that activation of spinal ERK might be involved in acute visceral pain arising from the uterine cervix. Copyright 2009 Elsevier Ltd. All rights reserved.

The Segmental Morphometric Properties of the Horse Cervical Spinal Cord: A Study of Cadaver

PubMed Central

Bahar, Sadullah; Bolat, Durmus; Selcuk, Muhammet Lutfi

2013-01-01

Although the cervical spinal cord (CSC) of the horse has particular importance in diseases of CNS, there is very little information about its segmental morphometry. The objective of the present study was to determine the morphometric features of the CSC segments in the horse and possible relationships among the morphometric features. The segmented CSC from five mature animals was used. Length, weight, diameter, and volume measurements of the segments were performed macroscopically. Lengths and diameters of segments were measured histologically, and area and volume measurements were performed using stereological methods. The length, weight, and volume of the CSC were 61.6 ± 3.2 cm, 107.2 ± 10.4 g, and 95.5 ± 8.3 cm3, respectively. The length of the segments was increased from C 1 to C 3, while it decreased from C 3 to C 8. The gross section (GS), white matter (WM), grey matter (GM), dorsal horn (DH), and ventral horn (VH) had the largest cross-section areas at C 8. The highest volume was found for the total segment and WM at C 4, GM, DH, and VH at C 7, and the central canal (CC) at C 3. The data obtained not only contribute to the knowledge of the normal anatomy of the CSC but may also provide reference data for veterinary pathologists and clinicians. PMID:23476145

Ventral cervical fusion at multiple levels using free vascularized double-islanded fibula - a technical report and review of the relevant literature.

PubMed

Krishnan, Kartik G; Müller, Adolf

2002-04-01

Reconstruction of the cervical spine using free vascularized bone flaps has been described in the literature. The reports involve either one level or, when multiple levels, they describe en bloc resection and reconstruction. Stabilization of different levels with a preserved intermediate segment with a single vascularized flap has not been described. We report on the case of a 55-year-old man, who had been operated several times using conventional techniques for cervical myelopathy and instability, who presented to us with severe neck pain. Diagnostic procedures showed pseudarthrosis of C3/4 and stress-overload of the C3/4 and C5/6 segments. The C4/5 fusion was adequately rigid, but avascular. We performed anterior cervical fusion at the C3/4 and C5/6 levels with a vascularized fibula flap modified as a double island. The rigidly fused C4/5 block was preserved and vascularized with the periosteum bridging the two fibular islands. The method and technique are described in detail. Fusion was adequate. Donor site morbidity was minimal and temporary. The patient is symptom free to date (25 months). The suggested method provides the possibility of vertebral fusion at different levels using a single vascularized flap. The indications for this procedure are (1) repeated failure of conventional methods, (2) established poor bone healing and bone non-union with avascular grafts and (3) a well-fused or preserved intermediate segment. The relevant literature is reviewed.

Surgical treatment of spondylodiscitis in the cervical spine: a minimum 2-year follow-up

PubMed Central

Boehm, Heinrich; El Saghir, Hesham; Tschöke, Sven K.; Kayser, Ralph

2006-01-01

Cervical spine spondylodiscitis is a rare, but serious manifestation of spinal infection. We present a retrospective study of 20 consecutive patients between 01/1994 and 12/1999 treated because of cervical spondylodiscitis. Mean age at the time of treatment was 59.7 (range 34–81) years, nine of them female. In all cases, diagnosis had been established with a delay. All patients in this series underwent surgery such as radical debridement, decompression if necessary, autologous bone grafting and instrumentation. Surgery was indicated if a neurological deficit, symptoms of sepsis, epidural abscess formation with consecutive stenosis, instability or severe deformity were present. Postoperative antibiotic therapy was carried out for 8–12 weeks. Follow-up examinations were performed a mean of 37 (range 24–63) months after surgery. Healing of the inflammation was confirmed in all cases by laboratory, clinical and radiological parameters. Spondylodesis was controlled radiologically and could be achieved in all cases. One case showed a 15°kyphotic angle in the proximal adjacent segment. Spontaneous bony bridging of the proximal adjacent segment was observed in one patient. In the other cases the adjacent segments radiologically showed neither fusion nor infection related changes. Preoperative neurological deficits improved in all cases. Residual neurological deficits persisted in three of eight cases. The results indicate that spondylodiscitis in cervical spine should be treated early and aggressive to avoid local and systemic complications. PMID:16868782

Mantle-crust interaction at the Blanco Ridge segment of the Blanco Transform Fault Zone: Results from the Blanco Transform Fault OBS Experiment

NASA Astrophysics Data System (ADS)

Kuna, V. M.; Nabelek, J.; Braunmiller, J.

2016-12-01

We present results of the Blanco Transform OBS Experiment, which consists of the deployment of 55 three-component broadband and short-period ocean bottom seismometers in the vicinity of the Blanco Fault Zone for the period between September 2012 and October 2013. Our research concentrates on the Blanco Ridge, a purely transform segment of the Blanco Fault Zone, that spans over 130 km between the Cascadia and the Gorda pull-apart depressions. Almost 3,000 well-constrained earthquakes were detected and located along the Blanco Ridge by an automatic procedure (using BRTT Antelope) and relocated using a relative location algorithm (hypoDD). The catalog magnitude of completeness is M=2.2 with an overall b value of 1. Earthquakes extend from 0 km to 20 km depth, but cluster predominantly at two depth levels: in the crust (5-7 km) and in the uppermost mantle (12-17 km). Statistical analysis reveals striking differences between crustal and mantle seismicity. The temporal distribution of crustal events follows common patterns given by Omori's law, while most mantle seismicity occurs in spatially tight sequences of unusually short durations lasting 30 minutes or less. These sequences cannot be described by known empirical laws. Moreover, we observe increased seismic activity in the uppermost mantle about 30 days before the largest (M=5.4) earthquake. Two mantle sequences occurred in a small area of 3x3 km about 4 and 2 weeks before the M=5.4 event. In the week leading up to the M=5.4 event we observe a significant downward migration of crustal seismicity, which results in the subsequent nucleation of the main event at the base of the crust. We hypothesize that the highly localized uppermost mantle seismicity is triggered by aseismic slow-slip of the surrounding ductile mantle. We also suggest that the mantle slip loads the crust eventually resulting in relatively large crustal earthquakes.

[Three dimensional finite element model of a modified posterior cervical single open-door laminoplasty].

PubMed

Wang, Q; Yang, Y; Fei, Q; Li, D; Li, J J; Meng, H; Su, N; Fan, Z H; Wang, B Q

2017-06-06

Objective: To build a three-dimensional finite element models of a modified posterior cervical single open-door laminoplasty with short-segmental lateral mass screws fusion. Methods: The C(2)-C(7) segmental data were obtained from computed tomography (CT) scans of a male patient with cervical spondylotic myelopathy and spinal stenosis.Three-dimensional finite element models of a modified cervical single open-door laminoplasty (before and after surgery) were constructed by the combination of software package MIMICS, Geomagic and ABAQUS.The models were composed of bony vertebrae, articulating facets, intervertebral disc and associated ligaments.The loads of moments 1.5Nm at different directions (flexion, extension, lateral bending and axial rotation)were applied at preoperative model to calculate intersegmental ranges of motion.The results were compared with the previous studies to verify the validation of the models. Results: Three-dimensional finite element models of the modified cervical single open- door laminoplasty had 102258 elements (preoperative model) and 161 892 elements (postoperative model) respectively, including C(2-7) six bony vertebraes, C(2-3)-C(6-7) five intervertebral disc, main ligaments and lateral mass screws.The intersegmental responses at the preoperative model under the loads of moments 1.5 Nm at different directions were similar to the previous published data. Conclusion: Three-dimensional finite element models of the modified cervical single open- door laminoplasty were successfully established and had a good biological fidelity, which can be used for further study.

Long-term Clinical Outcomes of Cervical Disc Arthroplasty: A Prospective, Randomized, Controlled Trial.

PubMed

Sasso, Willa R; Smucker, Joseph D; Sasso, Maria P; Sasso, Rick C

2017-02-15

Prospective, randomized, single-center, clinical trial. To prospectively examine the 7- and 10-year outcomes of cervical arthroplasty to anterior cervical discectomy and fusion (ACDF). Degeneration of the cervical discs causing radiculopathy is a frequent source of surgical intervention, commonly treated with ACDF. Positive clinical outcomes are associated with arthrodesis techniques, yet there remains a long-term concern for adjacent segment change. Cervical disc arthroplasty has been designed to mitigate some of the challenges associated with arthrodesis whereas providing for a similar positive neurological outcome. As data has been collected from numerous prospective US FDA IDE trials, longer term outcomes regarding adjacent segment change may be examined. As part of an FDA IDE trial, a single center collected prospective outcomes data on 47 patients randomized in a 1:1 ratio to ACDF or arthroplasty. Success of both surgical interventions remained high at the 10-year interval. Both arthrodesis and arthroplasty demonstrated statistically significant improvements in neck disability index, visual analog scale neck and arm pain scores at all intervals including 7- and 10-year periods. Arthroplasty demonstrated an advantage in comparison to arthrodesis as measured by final 10-year NDI score (8 vs. 16, P = 0.0485). Patients requiring reoperation were higher in number in the arthrodesis cohort (32%) in comparison with arthroplasty (9%) (P = 0.055). At 7 and 10 years, cervical arthroplasty compares favorably with ACDF as defined by standard outcomes scores in a highly selected population with radiculopathy. 1.

Clinical and Radiographic Results of Indirect Decompression and Posterior Cervical Fusion for Single-Level Cervical Radiculopathy Using an Expandable Implant with 2-Year Follow-Up.

PubMed

Siemionow, Kris; Janusz, Piotr; Phillips, Frank M; Youssef, Jim A; Isaacs, Robert; Tyrakowski, Marcin; McCormack, Bruce

2016-11-01

Background  Indirect posterior cervical nerve root decompression and fusion performed by placing bilateral posterior cervical cages in the facet joints from a posterior approach has been proposed as an option to treat select patients with cervical radiculopathy. The purpose of this study was to report 2-year clinical and radiologic results of this treatment method. Methods  Patients who failed nonsurgical management for single-level cervical radiculopathy were recruited. Surgical treatment involved a posterior approach with decortication of the lateral mass and facet joint at the treated level followed by placement of the DTRAX Expandable Cage (Providence Medical Technology, Lafayette, California, United States) into both facet joints. Iliac crest bone autograft was mixed with demineralized bone matrix and used in all cases. The Neck Disability Index (NDI), visual analog scale (VAS) for neck and arm pain, and SF-12 v.2 questionnaire were evaluated preoperatively and 2 years postoperatively. Segmental (treated level) and overall C2-C7 cervical lordosis, disk height, adjacent segment degeneration, and fusion were assessed on computed tomography scans and radiographs acquired preoperatively and 2 years postoperatively. Results  Overall, 53 of 60 enrolled patients were available at 2-year follow-up. There were 35 females and 18 males with a mean age of 53 years (range: 40-75 years). The operated level was C3-C4 ( N  = 3), C4-C5 ( N  = 6), C5-C6 ( N  = 36), and C6-C7 ( N  = 8). The mean preoperative and 2-year scores were NDI: 32.3 versus 9.1 ( p  < 0.0001); VAS Neck Pain: 7.4 versus 2.6 ( p  < 0.0001); VAS Arm Pain: 7.4 versus 2.6 ( p  < 0.0001); SF-12 Physical Component Summary: 34.6 versus 43.6 ( p  < 0.0001), and SF-12 Mental Component Summary: 40.8 versus 51.4 ( p  < 0.0001). No significant changes in overall or segmental lordosis were noted after surgery. Radiographic fusion rate was 98.1%. There was no device failure, implant lucency, or surgical reinterventions. Conclusions  Indirect decompression and posterior cervical fusion using an expandable intervertebral cage may be an effective tissue-sparing option in select patients with single-level cervical radiculopathy. Georg Thieme Verlag KG Stuttgart · New York.

Motion and dural sac compression in the upper cervical spine during the application of a cervical collar in case of unstable craniocervical junction—A study in two new cadaveric trauma models

PubMed Central

Hüttlin, Petra; Grützner, Paul A.; Weilbacher, Frank; Matschke, Stefan; Popp, Erik

2018-01-01

Background Unstable conditions of the craniocervical junction such as atlanto-occipital dislocation (AOD) or atlanto-axial instability (AAI) are severe injuries with a high risk of tetraplegia or death. Immobilization by a cervical collar to protect the patient from secondary damage is a standard procedure in trauma patients. If the application of a cervical collar to a patient with an unstable craniocervical condition may cause segmental motion and secondary injury to the spinal cord is unknown. The aim of the current study is (i) to analyze compression on the dural sac and (ii) to determine relative motion of the cervical spine during the procedure of applying a cervical collar in case of ligamentous unstable craniocervical junction. Methods and findings Ligamentous AOD as well as AOD combined with ligamentous AAI was simulated in two newly developed cadaveric trauma models. Compression of the dural sac and segmental angulation in the upper cervical spine were measured on video fluoroscopy after myelography during the application of a cervical collar. Furthermore, overall three-dimensional motion of the cervical spine was measured by a motion tracking system. In six cadavers each, the two new trauma models on AOD and AOD combined with AAI could be implemented. Mean dural sac compression was significantly increased to -1.1 mm (-1.3 to -0.7 mm) in case of AOD and -1.2 mm (-1.6 to -0.6 mm) in the combined model of AOD and AAI. Furthermore, there is a significant increased angulation at the C0/C1 level in the AOD model. Immense three-dimensional movement up to 22.9° of cervical spine flexion was documented during the procedure. Conclusion The current study pointed out that applying a cervical collar in general will cause immense three-dimensional movement. In case of unstable craniocervical junction, this leads to a dural sac compression and thus to possible damage to the spinal cord. PMID:29624623

Anatomic Relationship Between Right Recurrent Laryngeal Nerve and Cervical Fascia and Its Application Significance in Anterior Cervical Spine Surgical Approach.

PubMed

Shan, Jianlin; Jiang, Heng; Ren, Dajiang; Wang, Chongwei

2017-04-15

An anatomic study of anterior cervical dissection of 42 embalmed cadavers. The aim was to study the anatomic relationship between recurrent laryngeal nerve (RLN) and cervical fascia combined with the requirements in anterior cervical spine surgery (ACSS). There has been no systematic research about how to avoid RLN injury in anterior cervical spine surgical approach from the aspect of the anatomic relationship between RLN and cervical fascia. Forty-two adult cadavers were dissected to observe the relationships between RLN and different cervical fascia layers. RLN pierced out the alar fascia from the inner edge of the carotid sheath in all cases, and the piercing position in 22 cases (52.4%) was located at the lower segment of T1. The enter point into visceral fascia of RLN was located at C7-T1 in 25 cases (59.5%). The middle layer of deep cervical fascia exhibited the most stable anatomic relationship with RLN at the carotid sheath confluence site. Pulling visceral sheath leftwards would significantly increase the RLN tension. Using the close and stable relationship between RLN and cervical fascia could help to avoid RLN injury in anterior cervical spine surgical approach. 4.

The M6-C Cervical Disk Prosthesis: First Clinical Experience in 33 Patients.

PubMed

Thomas, Sam; Willems, Karel; Van den Daelen, Luc; Linden, Patrick; Ciocci, Maria-Cristina; Bocher, Philippe

2016-05-01

Retrospective study. To determine the short-term clinical succesrate of the M6-C cervical disk prosthesis in primary and secondary surgery. Cervical disk arthroplasty (CDA) provides an alternative to anterior cervical decompression and fusion for the treatment of spondylotic radiculopathy or myelopathy. The prevention of adjacent segment disease (ASD), a possible complication of anterior cervical decompression and fusion, is its most cited--although unproven--benefit. Unlike older arthroplasty devices that rely on a ball-and-socket-type design, the M6-C cervical disk prosthesis represents a new generation of unconstrained implants, developed to achieve better restoration of natural segmental biomechanics. This device should therefore optimize clinical performance of CDA and reduce ASD. All patients had preoperative computed tomography or magnetic resonance imaging and postoperative x-rays. Clinical outcome was assessed using the Neck Disability Index, a Visual Analog Scale, and the SF-36 questionnaire. Patients were asked about overall satisfaction and whether they would have the surgery again. Thirty-three patients were evaluated 17.1 months after surgery, on average. Nine patients had a history of cervical interventions. Results for Neck Disability Index, Visual Analog Scale, and SF-36 were significantly better among patients who had undergone primary surgery. In this group, 87.5% of patients reported a good or excellent result and 91.7% would have the procedure again. In contrast, all 4 device-related complications occurred in the small group of patients who had secondary surgery. The M6-C prosthesis appears to be a valuable addition to the CDA armatorium. It generates very good results in patients undergoing primary surgery, although its use in secondary surgery should be avoided. Longer follow-up is needed to determine to what measure this device can prevent ASD.

[Mid- to long-term outcomes of cervical disc arthroplasty for symptomatic cervical disc disease: a meta-analysis].

PubMed

Kan, S L; Yang, B; Ning, G Z; Gao, S J; Sun, J C; Feng, S Q

2016-12-01

Objective: To compare the benefits and harms of cervical disc arthroplasty (CDA) with anterior cervical discectomy and fusion(ACDF) for symptomatic cervical disc disease at mid- to long-term follow-up. Methods: Electronic searches were made in PubMed, EMBASE, and the Cochrane Library for randomized controlled trials with at least 48 moths follow-up.Outcomes were reported as relative risk or standardized mean difference.Meta-analysis was carried out using Revman version 5.3 and Stata version 12.0. Results: Seven trials were included, involving 2 302 participants.The results of this meta-analysis indicated that CDA brought about fewer secondary surgical procedures, lower neck disability index (NDI) scores, lower neck and arm pain scores, greater SF-36 Physical Component Summary (PCS) and Mental Component Summary(MCS) scores, greater range of motion (ROM) at the operative level and less superior adjacent-segment degeneration( P <0.05) than ACDF.CDA was not statistically different from ACDF in inferior adjacent-segment degeneration, neurological success, and adverse events ( P >0.05). Conclusions: CDA can significantly reduce the rates of secondary surgical procedures compared with ACDF.Meanwhile, CDA is superior or equivalent to ACDF in other aspects.As some studies without double-blind are included and some potential biases exites, more randomized controlled trials with high quality are required to get more reliable conclusions.

Stabilization with the Dynamic Cervical Implant: a novel treatment approach following cervical discectomy and decompression.

PubMed

Matgé, Guy; Berthold, Christophe; Gunness, Vimal Raj Nitish; Hana, Ardian; Hertel, Frank

2015-03-01

Although cervical total disc replacement (TDR) has shown equivalence or superiority to anterior cervical discectomy and fusion (ACDF), potential problems include nonphysiological motion (hypermobility), accelerated degeneration of the facet joints, particulate wear, and compromise of the mechanical integrity of the endplate during device fixation. Dynamic cervical stabilization is a novel motion-preserving concept that facilitates controlled, limited flexion and extension, but prevents axial rotation and lateral bending, thereby reducing motion across the facet joints. Shock absorption of the Dynamic Cervical Implant (DCI) device is intended to protect adjacent levels from accelerated degeneration. The authors conducted a prospective evaluation of 53 consecutive patients who underwent DCI stabilization for the treatment of 1-level (n = 42), 2-level (n = 9), and 3-level (n = 2) cervical disc disease with radiculopathy or myelopathy. Forty-seven patients (89%) completed all clinical and radiographic outcomes at a minimum of 24 months. Clinical outcomes consisted of Neck Disability Index (NDI) and visual analog scale (VAS) scores, neurological function at baseline and at latest follow-up, as well as patient satisfaction. Flexion-extension radiography was evaluated for device motion, implant migration, subsidence, and heterotopic ossification. Cervical sagittal alignment (Cobb angle), functional spinal unit (FSU) angle, and range of motion (ROM) at index and adjacent levels were evaluated with WEB 1000 software. The NDI score, VAS neck and arm pain scores, and neurological deficits were significantly reduced at each postoperative time point compared with baseline (p < 0.0001). At 24 months postoperatively, 91% of patients were very satisfied and 9% somewhat satisfied, while 89% would definitely and 11% would probably elect to have the same surgery again. In 47 patients with 58 operated levels, the radiographic assessment showed good motion (5°-12°) of the device in 57%, reduced motion (2°-5°) in 34.5%, and little motion (0-2°) in 8.5%. The Cobb and FSU angles improved, showing a clear tendency for lordosis with the DCI. Motion greater than 2° of the treated segment could be preserved in 91.5%, while 8.5% had a near segmental fusion. Mean ROM at index levels demonstrated satisfying motion preservation with DCI. Mean ROM at upper and lower adjacent levels showed maintenance of adjacent-level kinematics. Heterotopic ossification, including 20% minor and 15% major, had no direct impact on clinical results. There were 2 endplate subsidences detected with an increased segmental lordosis. One asymptomatic anterior device migration required reoperation. Three patients underwent a secondary surgery in another segment during follow-up, twice for a new disc herniation and once for an adjacent degeneration. There was no posterior migration and no device breakage. Preliminary results indicate that the DCI implanted using a proper surgical technique is safe and facilitates excellent clinical outcomes, maintains index-and adjacent-level ROM in the majority of cases, improves sagittal alignment, and may be suitable for patients with facet arthrosis who would otherwise not be candidates for cervical TDR. Shock absorption together with maintained motion in the DCI may protect adjacent levels from early degeneration in longer follow-up.

Mechanical role of the posterior column components in the cervical spine.

PubMed

Hartman, Robert A; Tisherman, Robert E; Wang, Cheng; Bell, Kevin M; Lee, Joon Y; Sowa, Gwendolyn A; Kang, James D

2016-07-01

To quantify the mechanical role of posterior column components in human cervical spine segments. Twelve C6-7 segments were subjected to resection of (1) suprasinous/interspinous ligaments (SSL/ISL), (2) ligamenta flavum (LF), (3) facet capsules, and (4) facets. A robot-based testing system performed repeated flexibility testing of flexion-extension (FE), axial rotation (AR), and lateral bending (LB) to 2.5Nm and replayed kinematics from intact flexibility tests for each state. Range-of-motion, stiffness, moment resistance and resultant forces were calculated. The LF contributes largely to moment resistance, particularly in flexion. Facet joints were primary contributors to AR and LB mechanics. Moment/force responses were more sensitive and precise than kinematic outcomes. The LF is mechanically important in the cervical spine; its injury could negatively impact load distribution. Damage to facets in a flexion injury could lead to AR or LB hypermobility. Quantifying the contribution of spinal structures to moment resistance is a sensitive, precise process for characterizing structural mechanics.

[Comparison between the Range of Movement Canine Real Cervical Spine and Numerical Simulation - Computer Model Validation].

PubMed

Srnec, R; Horák, Z; Sedláček, R; Sedlinská, M; Krbec, M; Nečas, A

2017-01-01

PURPOSE OF THE STUDY In developing new or modifying the existing surgical treatment methods of spine conditions an integral part of ex vivo experiments is the assessment of mechanical, kinematic and dynamic properties of created constructions. The aim of the study is to create an appropriately validated numerical model of canine cervical spine in order to obtain a tool for basic research to be applied in cervical spine surgeries. For this purpose, canine is a suitable model due to the occurrence of similar cervical spine conditions in some breeds of dogs and in humans. The obtained model can also be used in research and in clinical veterinary practice. MATERIAL AND METHODS In order to create a 3D spine model, the LightSpeed 16 (GE, Milwaukee, USA) multidetector computed tomography was used to scan the cervical spine of Doberman Pinscher. The data were transmitted to Mimics 12 software (Materialise HQ, Belgium), in which the individual vertebrae were segmented on CT scans by thresholding. The vertebral geometry was exported to Rhinoceros software (McNeel North America, USA) for modelling, and subsequently the specialised software Abaqus (Dassault Systemes, France) was used to analyse the response of the physiological spine model to external load by the finite element method (FEM). All the FEM based numerical simulations were considered as nonlinear contact statistic tasks. In FEM analyses, angles between individual spinal segments were monitored in dependence on ventroflexion/ /dorziflexion. The data were validated using the latero-lateral radiographs of cervical spine of large breed dogs with no evident clinical signs of cervical spine conditions. The radiographs within the cervical spine range of motion were taken at three different positions: in neutral position, in maximal ventroflexion and in maximal dorziflexion. On X-rays, vertebral inclination angles in monitored spine positions were measured and compared with the results obtain0ed from FEM analyses of the numerical model. RESULTS It is obvious from the results that the physiological spine model tested by the finite element method shows a very similar mechanical behaviour as the physiological canine spine. The biggest difference identified between the resulting values was reported in C6-C7 segment in dorsiflexion (Δφ = 5.95%), or in C4-C5 segment in ventroflexion (Δφ = -3.09%). CONCLUSIONS The comparisons between the mobility of cervical spine in ventroflexion/dorsiflexion on radiographs of the real models and the simulated numerical model by finite element method showed a high degree of results conformity with a minimal difference. Therefore, for future experiments the validated numerical model can be used as a tool of basic research on condition that the results of analyses carried out by finite element method will be affected only by an insignificant error. The computer model, on the other hand, is merely a simplified system and in comparison with the real situation cannot fully evaluate the dynamics of the action of forces in time, their variability, and also the individual effects of supportive skeletal tissues. Based on what has been said above, it is obvious that there is a need to exercise restraint in interpreting the obtained results. Key words: cervical spine, kinematics, numerical modelling, finite element method, canine.

Facetal distraction as treatment for single- and multilevel cervical spondylotic radiculopathy and myelopathy: a preliminary report.

PubMed

Goel, Atul; Shah, Abhidha

2011-06-01

The authors discuss their successful preliminary experience with 36 cases of cervical spondylotic disease by performing facetal distraction using specially designed Goel cervical facet spacers. The clinical and radiological results of treatment are analyzed. The mechanism of action of the proposed spacers and the rationale for their use are evaluated. Between 2006 and February 2010, 36 patients were treated using the proposed technique. Of these patients, 18 had multilevel and 18 had single-level cervical spondylotic radiculopathy and/or myelopathy. The average follow-up period was 17 months with a minimum of 6 months. The Japanese Orthopaedic Association classification system, visual analog scale (neck pain and radiculopathy), and Odom criteria were used to monitor the clinical status of the patient. The patients were prospectively analyzed. The technique of surgery involved wide opening of the facet joints, denuding of articular cartilage, distraction of facets, and forced impaction of Goel cervical facet spacers into the articular cavity. Additionally, the interspinous process ligaments were resected, and corticocancellous bone graft from the iliac crest was placed and was stabilized over the adjoining laminae and facets after adequately preparing the host bone. Eighteen patients underwent single-level, 6 patients underwent 2-level, and 12 patients underwent 3-level treatment. The alterations in the physical architecture of spine and canal dimensions were evaluated before and after the placement of intrafacet joint spacers and after at least 6 months of follow-up. All patients had varying degrees of relief from symptoms of pain, radiculopathy, and myelopathy. Analysis of radiological features suggested that the distraction of facets with the spacers resulted in an increase in the intervertebral foraminal dimension (mean 2.2 mm), an increase in the height of the intervertebral disc space (range 0.4-1.2 mm), and an increase in the interspinous distance (mean 2.2 mm). The circumferential distraction resulted in reduction in the buckling of the posterior longitudinal ligament and ligamentum flavum. The procedure ultimately resulted in segmental bone fusion. No patient worsened after treatment. There was no noticeable implant malfunction. During the follow-up period, all patients had evidence of segmental bone fusion. No patient underwent reexploration or further surgery of the neck. Distraction of the facets of the cervical vertebra can lead to remarkable and immediate stabilization-fixation of the spinal segment and increase in space for the spinal cord and roots. The procedure results in reversal of several pathological events related to spondylotic disease. The safe, firm, and secure stabilization at the fulcrum of cervical spinal movements provided a ground for segmental spinal arthrodesis. The immediate postoperative improvement and lasting recovery from symptoms suggest the validity of the procedure.

Analysis of digitized cervical images to detect cervical neoplasia

NASA Astrophysics Data System (ADS)

Ferris, Daron G.

2004-05-01

Cervical cancer is the second most common malignancy in women worldwide. If diagnosed in the premalignant stage, cure is invariably assured. Although the Papanicolaou (Pap) smear has significantly reduced the incidence of cervical cancer where implemented, the test is only moderately sensitive, highly subjective and skilled-labor intensive. Newer optical screening tests (cervicography, direct visual inspection and speculoscopy), including fluorescent and reflective spectroscopy, are fraught with certain weaknesses. Yet, the integration of optical probes for the detection and discrimination of cervical neoplasia with automated image analysis methods may provide an effective screening tool for early detection of cervical cancer, particularly in resource poor nations. Investigative studies are needed to validate the potential for automated classification and recognition algorithms. By applying image analysis techniques for registration, segmentation, pattern recognition, and classification, cervical neoplasia may be reliably discriminated from normal epithelium. The National Cancer Institute (NCI), in cooperation with the National Library of Medicine (NLM), has embarked on a program to begin this and other similar investigative studies.

Developmental biomechanics of the human cervical spine.

PubMed

Nuckley, David J; Linders, David R; Ching, Randal P

2013-04-05

Head and neck injuries, the leading cause of death for children in the U.S., are difficult to diagnose, treat, and prevent because of a critical void in our understanding of the biomechanical response of the immature cervical spine. The objective of this study was to investigate the functional and failure biomechanics of the cervical spine across multiple axes of loading throughout maturation. A correlational study design was used to examine the relationships governing spinal maturation and biomechanical flexibility curves and tolerance data using a cadaver human in vitro model. Eleven human cadaver cervical spines from across the developmental spectrum (2-28 years) were dissected into segments (C1-C2, C3-C5, and C6-C7) for biomechanical testing. Non-destructive flexibility tests were performed in tension, compression, flexion, extension, lateral bending, and axial rotation. After measuring their intact biomechanical responses, each segment group was failed in different modes to measure the tissue tolerance in tension (C1-C2), compression (C3-C5), and extension (C5-C6). Classical injury patterns were observed in all of the specimens tested. Both the functional (p<0.014) and failure (p<0.0001) mechanics exhibited significant relationships with age. Nonlinear flexibility curves described the functional response of the cervical spine throughout maturation and elucidated age, spinal level, and mode of loading specificity. These data support our understanding of the child cervical spine from a developmental perspective and facilitate the generation of injury prevention or management schema for the mitigation of child spine injuries and their deleterious effects. Copyright © 2013 Elsevier Ltd. All rights reserved.

Design limitations of Bryan disc arthroplasty.

PubMed

Fong, Shee Yan; DuPlessis, Stephan J; Casha, Steven; Hurlbert, R John

2006-01-01

Disc arthroplasty is gaining momentum as a surgical procedure in the treatment of spinal degenerative disease. Results must be carefully scrutinized to recognize benefits as well as limitations. The aim of this study was to investigate factors associated with segmental kyphosis after Bryan disc replacement. Prospective study of a consecutively enrolled cohort of 10 patients treated in a single center using the Bryan cervical disc prosthesis for single-level segmental reconstruction in the surgical treatment of cervical radiculopathy and/or myelopathy. Radiographic and quality of life outcome measures. Static and dynamic lateral radiographs were digitally analyzed in patients undergoing Bryan disc arthroplasty throughout a minimum 3-month follow-up period. Observations were compared with preoperative studies looking for predictive factors of postoperative spinal alignment. Postoperative end plate angles through the Bryan disc in the neutral position were kyphotic in 9 of 10 patients. Compared with preoperative end plate angulation there was a mean change of -7 degrees (towards kyphosis) in postoperative end plate alignment (p=.007, 95% confidence interval [CI] -6 degrees to -13 degrees). This correlated significantly with postoperative reduction in posterior vertebral body height of the caudal segment (p=.011, r2=.575) and postoperative functional spine unit (FSU) kyphosis (p=.032, r2=.46). Despite intraoperative distraction, postoperative FSU height was significantly reduced, on average by 1.7 mm (p=.040, 95% CI 0.5-2.8 mm). Asymmetrical end plate preparation occurs because of suboptimal coordinates to which the milling jig is referenced. Although segmental motion is preserved, Bryan disc arthroplasty demonstrates a propensity towards kyphotic orientation through the prosthesis likely as a result of intraoperative lordotic distraction. FSU angulation tends towards kyphosis and FSU height is decreased in the postoperative state from lack of anterior column support. Limitations of Bryan cervical disc arthroplasty should be carefully considered when reconstruction or maintenance of cervical lordosis is desirable.

Kinematic relationship between missed ligamentum flavum bulge and degenerative factors in the cervical spine.

PubMed

Zhong, Guibin; Buser, Zorica; Lao, Lifeng; Yin, Ruofeng; Wang, Jeffrey C

2015-10-01

Bulging of ligamentum flavum can happen with the aging process and can lead to compression of the spinal cord and nerves. However, the distribution and the risk factors associated with a missed ligamentum flavum bulge (LFB) are unknown. The aim was to evaluate the distribution and risk factors associated with missed LFB in the cervical spine. This was a retrospective analysis of kinematic magnetic resonance images (kMRI). Patients diagnosed with symptomatic neck pain or radiculopathy between March 2011 and October 2012 were included. The outcome measures were missed LFB and degenerative factors. A total of 200 patients (1,000 cervical segments) underwent upright kMRI in neutral, flexion, and extension postures. The LFB, sagittal cervical angles, disc herniation, disc degeneration, disc height, angular motion, translational motion, age, and gender were recorded. After excluding segments with LFB in neutral and flexion position, Pearson and Spearman correlation coefficients were used to evaluate the relation between the risk factors and missed LFB in the extension position. The average depth of LFB was 0.24±0.71 mm at C2-C3, 1.02±1.42 mm at C3-C4, 1.65±1.48 mm at C4-C5, 2.13±1.37 mm at C5-C6, and 1.05±1.54 mm at C6-C7. The distribution of LFB was the most frequent at C5-C6 level (76.58%) followed by C4-C5 (63.06%). Disc herniation, disc degeneration, angular variation, and translational motion were significantly correlated with missed LFB at C4-C5 andC5-C6. Disc degeneration was the only factor significantly correlated with missed LFB at all cervical segments. Occurrence and depth of missed LFB was the highest at C4-C5 and C5-C6 compared with other cervical levels. Disc degeneration, disc herniation, angular variation, and translational motion could play a role in the development of LFB at C4-C5 andC5-C6. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison between effectiveness of Mechanical and Manual Traction combined with mobilization and exercise therapy in Patients with Cervical Radiculopathy.

PubMed

Bukhari, Syed Rehan Iftikhar; Shakil-Ur-Rehman, Syed; Ahmad, Shakeel; Naeem, Aamer

2016-01-01

Cervical radiculopathy is a common neuro-musculo-skeletal disorder causing pain and disability. Traction is part of the evidence based manual physical therapy management due to its mechanical nature, type of traction and parameters related to its applicability and are still to be explored more through research. Our objective was to determine the Effects of Mechanical versus Manual Traction in Manual Physical Therapy combined with segmental mobilization and exercise therapy in the physical therapy management of Patients with Cervical Radiculopathy. This randomized control trial was conducted at department of physical therapy and rehabilitation, Rathore Hospital Faisalabad, from February to July 2015. Inclusion criteria were both male and female patients with evident symptoms of cervical spine radiculopathy and age ranged between 20-70 years. The exclusion criteria were Patients with history of trauma, neck pain without radiculopathy, aged less than 20 and more than 70. A total of 72 patients with cervical radiculopathy were screened out as per the inclusion criteria, 42 patients were randomly selected and placed into two groups by toss and trial method, and only 36 patients completed the study, while 6 dropped out. The mechanical traction was applied in group A and manual traction in group B along with common intervention of segmental mobilization and exercise therapy in both groups for 6 weeks. The patient's outcomes were assessed by self reported NPRS and NDI at the baseline and after completion of 06 weeks exercise program at 3 days per week. The data was analyzed through SPSS version-21, and paired T test was applied at 95% level significance to determine the statistical deference between two groups. Clinically the group of patients treated with mechanical traction managed pain (mean pre 6.26, mean post 1.43), and disability (mean pre 24.43 and mean post 7.26) more effectively as compared with the group of patients treated with manual traction (Pain mean pre 6.80, mean post 3.85 and disability mean pre 21.92 and post 12.19). Statistically the results of both mechanical and manual traction techniques are equally significant in group A and B for pain and disability (p-value less than 0.05). If patients of cervical radiculopathy treated with mechanical traction, segmental mobilization, and exercise therapy will manage pain and disability more effectively than treated with manual traction, segmental mobilization, and exercise therapy.

Application of Piezosurgery in Anterior Cervical Corpectomy and Fusion.

PubMed

Pan, Sheng-Fa; Sun, Yu

2016-05-01

Anterior cervical corpectomy and fusion (ACCF) is frequently used to decompress the cervical spine; however, this procedure is risky when dealing with a hard disc or ossification of the posterior longitudinal ligament (OPLL). Piezosurgery offers a useful tool for performing this procedure. In this article, we present a 50 years old man who had cervical spondylotic myelopathy with OPLL at the C 6 level and segmental stenosis of the cervical spinal canal. When removing the posterior wall of his C 6 vertebral body and OPLL, piezosurgery was used to selectively cut hard structures piece by piece without injuring delicate soft tissues like the nerve roots and spinal cord. Because there is no bleeding from the bone surface with piezosurgery, it provides a clean operative field. © 2016 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

Is the radiographic subsidence of stand-alone cages associated with adverse clinical outcomes after cervical spine fusion? An observational cohort study with 2-year follow-up outcome scoring.

PubMed

Zajonz, Dirk; Franke, Anne-Catherine; von der Höh, Nicolas; Voelker, Anna; Moche, Michael; Gulow, Jens; Heyde, Christoph-Eckhard

2014-01-01

The stand-alone treatment of degenerative cervical spine pathologies is a proven method in clinical practice. However, its impact on subsidence, the resulting changes to the profile of the cervical spine and the possible influence of clinical results compared to treatment with additive plate osteosynthesis remain under discussion until present. This study was designed as a retrospective observational cohort study to test the hypothesis that radiographic subsidence of cervical cages is not associated with adverse clinical outcomes. 33 cervical segments were treated surgically by ACDF with stand-alone cage in 17 patients (11 female, 6 male), mean age 56 years (33-82 years), and re-examined after eight and twenty-six months (mean) by means of radiology and score assessment (Medical Outcomes Study Short Form (MOS-SF 36), Oswestry Neck Disability Index (ONDI), painDETECT questionnaire and the visual analogue scale (VAS)). Subsidence was observed in 50.5% of segments (18/33) and 70.6% of patients (12/17). 36.3% of cases of subsidence (12/33) were observed after eight months during mean time of follow-up 1. After 26 months during mean time of follow-up 2, full radiographic fusion was seen in 100%. MOS-SF 36, ONDI and VAS did not show any significant difference between cases with and without subsidence in the two-sample t-test. Only in one type of scoring (painDETECT questionnaire) did a statistically significant difference in t-Test emerge between the two groups (p = 0.03; α = 0.05). However, preoperative painDETECT score differ significantly between patients with subsidence (13.3 falling to 12.6) and patients without subsidence (7.8 dropped to 6.3). The radiological findings indicated 100% healing after stand-alone treatment with ACDF. Subsidence occurred in 50% of the segments treated. No impact on the clinical results was detected in the medium-term study period.

Artificial Disk Replacement Combined With Fusion Versus 2-Level Fusion in Cervical 2-Level Disk Disease With a 5-Year Follow-up.

PubMed

Ji, Gyu Yeul; Oh, Chang Hyun; Shin, Dong Ah; Ha, Yoon; Yi, Seong; Kim, Keung Nyun; Shin, Hyun Cheol; Yoon, Do Heum

2017-06-01

Prospective study. The purpose of this study was to compare the long-term clinical and radiologic outcomes of hybrid surgery (HS) and 2-level anterior cervical discectomy and fusion (2-ACDF) in patients with 2-level cervical disk disease. In a previous study with a 2-year follow-up, HS was shown to be superior to 2-ACDF, with a better Neck Disability Index (NDI) score, less postoperative neck pain, faster C2-C7 range of motion (ROM) recovery, and less adjacent ROM increase. Between 2004 and 2006, 40 patients undergoing 2-level cervical disk surgery at our hospital were identified as 2-level degenerative disk disease. Forty patients were included in the previous study; 35 patients were followed up for 5 years. Patients completed the NDI and graded their pain intensity before surgery and at routine postoperative until 5 years. Dynamic cervical radiographs were obtained before surgery and at routine postoperative intervals and the angular ROM for C2-C7 and adjacent segments was measured. The HS group had better NDI recovery until 3 years after surgery (P<0.05). Postoperative neck pain was lower in the HS group at 1 and 3 years after surgery (P<0.05), but arm pain relief was not differently relieved. The HS group showed more angular ROM for C2-C7 at 2 and 3 years after surgery. The superior adjacent segment ROM showed hypermobility in the 2-ACDF group and hypomobility in the HS group at all follow-up periods without statistically significance, but the inferior adjacent segment ROM differed significantly (P<0.05). HS is superior to 2-ACDF; it leads to better NDI recovery, less postoperative neck pain, faster C2-C7 ROM recovery, and less adjacent ROM increase over a 2-year follow-up, but these benefits of HS become similar to those of 2-ACDF with 5 years of follow-up.

Application of an asymmetric finite element model of the C2-T1 cervical spine for evaluating the role of soft tissues in stability.

PubMed

Erbulut, D U; Zafarparandeh, I; Lazoglu, I; Ozer, A F

2014-07-01

Different finite element models of the cervical spine have been suggested for evaluating the roles of ligaments, facet joints, and disks in the stability of cervical spine under sagittal moments. However, no comprehensive study on the response of the full cervical spine that has used a detailed finite element (FE) model (C2-T1) that considers the asymmetry about the mid-sagittal plane has been reported. The aims of this study were to consider asymmetry in a FE model of the full cervical spine and to investigate the influences of ligaments, facet joints, and disk nucleus on the stability of the asymmetric model during flexion and extension. The model was validated against various published in vitro studies and FE studies for the three main loading planes. Next, the C4-C5 level was modified to simulate different cases to investigate the role of the soft tissues in segmental stability. The FE model predicted that excluding the interspinous ligament (ISL) from the index level would cause excessive instability during flexion and that excluding the posterior longitudinal ligament (PLL) or the ligamentum flavum (LF) would not affect segmental rotation. During extension, motion increased when the facet joints were excluded. The model without disk nucleus was unstable compared to the intact model at lower loads and exhibited a similar rotation response at higher loads. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

Kinetic DTI of the cervical spine: diffusivity changes in healthy subjects.

PubMed

Kuhn, Félix P; Feydy, Antoine; Launay, Nathalie; Lefevre-Colau, Marie-Martine; Poiraudeau, Serge; Laporte, Sébastien; Maier, Marc A; Lindberg, Pavel

2016-09-01

The study aims to assess the influence of neck extension on water diffusivity within the cervical spinal cord. IRB approved the study in 22 healthy volunteers. All subjects underwent anatomical MR and diffusion tensor imaging (DTI) at 1.5 T. The cervical cord was imaged in neutral (standard) position and extension. Segmental vertebral rotations were analyzed on sagittal T2-weighted images using the SpineView® software. Spinal cord diffusivity was measured in cross-sectional regions of interests at multiple levels (C1-C5). As a result of non-adapted coil geometry for spinal extension, 10 subjects had to be excluded. Image quality of the remaining 12 subjects was good without any deteriorating artifacts. Quantitative measurements of vertebral rotation angles and diffusion parameters showed good intra-rater reliability (ICC = 0.84-0.99). DTI during neck extension revealed significantly decreased fractional anisotropy (FA) and increased radial diffusivity (RD) at the C3 level and increased apparent diffusion coefficients (ADC) at the C3 and C4 levels (p < 0.01 Bonferroni corrected). The C3/C4 level corresponded to the maximal absolute change in segmental vertebral rotation between the two positions. The increase in RD correlated positively with the degree of global extension, i.e., the summed vertebral rotation angle between C1 and C5 (R = 0.77, p = 0.006). Our preliminary results suggest that DTI can quantify changes in water diffusivity during cervical spine extension. The maximal differences in segmental vertebral rotation corresponded to the levels with significant changes in diffusivity (C3/C4). Consequently, kinetic DTI measurements may open new perspectives in the assessment of neural tissue under biomechanical constraints.

Head pain referral during examination of the neck in migraine and tension-type headache.

PubMed

Watson, Dean H; Drummond, Peter D

2012-09-01

To investigate if and to what extent typical head pain can be reproduced in tension-type headache (TTH), migraine without aura sufferers, and controls when sustained pressure was applied to the lateral posterior arch of C1 and the articular pillar of C2, stressing the atlantooccipital and C2-3 segments respectively. Occipital and neck symptoms often accompany primary headache, suggesting involvement of cervical afferents in central pain processing mechanisms in these disorders. Referral of head pain from upper cervical structures is made possible by convergence of cervical and trigeminal nociceptive afferent information in the trigemino-cervical nucleus. Upper cervical segmental and C2-3 zygapophysial joint dysfunction is recognized as a potential source of noxious afferent information and is present in primary headache sufferers. Furthermore, referral of head pain has been demonstrated from symptomatic upper cervical segments and the C2-3 zygapophysial joints, suggesting that head pain referral may be a characteristic of cervical afferent involvement in headache. Thirty-four headache sufferers and 14 controls were examined interictally. Headache patients were diagnosed according the criteria of the International Headache Society and comprised 20 migraine without aura (females n = 18; males n = 2; average age 35.3 years) and 14 TTH sufferers (females n = 11; males n = 3; average age 30.7 years). Two techniques were used specifically to stress the atlantooccipital segments (Technique 1 - C1) and C2-3 zygapophysial joints (Technique 2 - C2). Two techniques were also applied to the arm--the common extensor origin and the mid belly of the biceps brachii. Participants reported reproduction of head pain with "yes" or "no" and rated the intensity of head pain and local pressure of application on a scale of 0 -10, where 0 = no pain and 10 = intolerable pain. None of the subjects reported head pain during application of techniques on the arm. Head pain referral during the cervical examination was reported by 8 of 14 (57%) control participants, all TTH patients and all but 1 migraineur (P < .002). In each case, participants reported that the referred head pain was similar to the pain they usually experienced during TTH or migraine. The frequency of head pain referral was identical for Techniques 1 and 2. The intensity of referral did not differ between Technique 1 and Technique 2 or between groups. Tenderness ratings to thumb pressure were comparable between the Techniques 1 and 2 when pressure was applied to C1 and C2 respectively and across groups. Similarly, there were no significant differences for tenderness ratings to thumb pressure between Technique 1 and Technique 2 on the arm or between groups. While tenderness ratings to thumb pressure for Technique 2 were similar for both referral (n = 41) and non-referral (n = 7) groups, tenderness ratings for Technique 1 in the referral group were significantly greater when compared with the non-referral group (P = .01). Our data support the continuum concept of headache, one in which noxious cervical afferent information may well be significantly underestimated. The high incidence of reproduction of headache supports the evaluation of musculoskeletal features in patients presenting with migrainous and TTH symptoms. This, in turn, may have important implications for understanding the pathophysiology of headache and developing alternative treatment options. © 2012 American Headache Society.

Surgical management of metastatic tumors of the cervical spine.

PubMed

Davarski, Atanas N; Kitov, Borislav D; Zhelyazkov, Christo B; Raykov, Stefan D; Kehayov, Ivo I; Koev, Ilyan G; Kalnev, Borislav M

2013-01-01

To present the results from the clinical presentation, the imaging diagnostics, surgery and postoperative status of 17 patients with cervical spine metastases, to analyse all data and make the respective conclusions and compare them with the available data in the literature. The study analysed data obtained by patients with metastatic cervical tumours treated in St George University Hospital over a period of seven years. All patients underwent diagnostic imaging tests which included, separately or in combination, cervical x-rays, computed tomography scan and magnetic-resonance imaging. Severity of neurological damage and its pre- and postoperative state was graded according to the Frankel Scale. For staging and operating performance we used the Tomita scale and Harrington classification. Seven patients had only one affected vertebra, 4 patients--two vertebrae, one patient--three vertebrae, 2 patients--four vertebrae, and in the other 3 patients more than one segment was affected. Surgery was performed in 12 patients. One level anterior corpectomy was performed in 6 patients, three patients had two-level surgery, and one patient--three-level corpectomy; in the remaining 2 cases we used posterior approach in surgery. Complete corpectomy was performed in 4 patients, subtotal corpectomy was used in 6 patients and partial--in 2 patients. Anterior stabilization system ADD plus (Ulrich GmbH & Co. KG, Ulm, Germany) was implanted in 2 patients; in 8 patients anterior titanium plate and bone graft were used, and in 1 patient--posterior cervical stabilization system. Because of the pronounced pain syndrome and frequent neurological lesions as a result of the cervical spine metastases use of surgery is justified. The main purpose is to maximize tumor resection, achieve optimal spinal cord and nerve root decompression and stabilize the affected segment.

Influence of stabilization occlusal splint on craniocervical relationships. Part I: Cephalometric analysis.

PubMed

Moya, H; Miralles, R; Zuñiga, C; Carvajal, R; Rocabado, M; Santander, H

1994-01-01

This study was conducted in order to determine the effect of an occlusal splint on craniocervical relationships, in subjects with muscle spasms in the sternocleidomastoid and trapezius muscles. A full-arch maxillary stabilization occlusal splint was made for each of the 15 subjects. Two lateral craniocervical radiographs were taken for each subject, with and without an occlusal splint. Cephalometric analysis showed that the splint caused a significant extension of the head on the cervical spine. There was also a significant decrease in the cervical spine lordosis in the first, second and third cervical segment. These cervical changes could be a compensation mechanism caused by the extension of the cranium on the upper cervical spine. The change in the curvature implies that it is necessary to periodically evaluate the changes occurring in the craniocervical relationships after the occlusal splint has been inserted.

Effect of energy density and delay time on the degree of conversion and Knoop microhardness of a dual resin cement.

PubMed

Mainardi, Maria do Carmo A J; Giorgi, Maria Cecília C; Lima, Débora A N L; Marchi, Giselle M; Ambrosano, Gláucia M; Paulillo, Luiz A M S; Aguiar, Flávio H B

2015-02-01

In the present study, we evaluated the influence of the photo-curing delay time and energy density on the degree of conversion and the Knoop microhardness of a resin cement. Seventy-eight samples were assigned to 13 groups (n = 6), one of which received no light curing (control). The samples were made of a dual-cured resin cement (RelyX ARC) with the aid of a Teflon matrix, submitted to one of the following energy densities (J/cm²): 7, 14, 20, and 28. Delay times were immediate (0), 1 min, or 2 min. After 24 h, the degree of conversion and microhardness were measured at three segments: cervical, medium, and apical. Data were submitted to three-way anova and Tukey's and Dunnett's tests, the latest of which was used to compare the control to the experimental groups. No interaction was observed between delay time and energy density regarding the degree of conversion. The cervical segment showed the highest values, while the apical showed the lowest. Microhardness values concerning the cervical segment in all groups were statistically different from that obtained for the control. A high-irradiance light-curing unit allows for a reduced irradiation exposure time with a short delay time, aimed at tooth restorations using a dual-cured resin cement. © 2014 Wiley Publishing Asia Pty Ltd.

Can an Endplate-conformed Cervical Cage Provide a Better Biomechanical Environment than a Typical Non-conformed Cage?: A Finite Element Model and Cadaver Study.

PubMed

Zhang, Fan; Xu, Hao-Cheng; Yin, Bo; Xia, Xin-Lei; Ma, Xiao-Sheng; Wang, Hong-Li; Yin, Jun; Shao, Ming-Hao; Lyu, Fei-Zhou; Jiang, Jian-Yuan

2016-08-01

To evaluate the biomechanical characteristics of endplate-conformed cervical cages by finite element method (FEM) analysis and cadaver study. Twelve specimens (C2 -C7 ) and a finite element model (C3 -C7 ) were subjected to biomechanical evaluations. In the cadaver study, specimens were randomly assigned to intact (I), endplate-conformed (C) and non-conformed (N) groups with C4-5 discs as the treated segments. The morphologies of the endplate-conformed cages were individualized according to CT images of group C and the cages fabricated with a 3-D printer. The non-conformed cages were wedge-shaped and similar to commercially available grafts. Axial pre-compression loads of 73.6 N and moment of 1.8 Nm were used to simulate flexion (FLE), extension (EXT), lateral bending (LB) and axial rotation (AR). Range of motion (ROM) at C4-5 of each specimen was recorded and film sensors fixed between the cages and C5 superior endplates were used to detect interface stress. A finite element model was built based on the CT data of a healthy male volunteer. The morphologies of the endplate-conformed and wedge-shaped, non-conformed cervical cages were both simulated by a reverse engineering technique and implanted at the segment of C4-5 in the finite element model for biomechanical evaluation. Force loading and grouping were similar to those applied in the cadaver study. ROM of C4-5 in group I were recorded to validate the finite element model. Additionally, maximum cage-endplate interface stresses, stress distribution contours on adjoining endplates, intra-disc stresses and facet loadings at adjacent segments were measured and compared between groups. In the cadaver study, Group C showed a much lower interface stress in all directions of motion (all P < 0.05) and the ROM of C4-5 was smaller in FLE-EXT (P = 0.001) but larger in AR (P = 0.017). FEM analysis produced similar results: the model implanted with an endplate-conformed cage presented a lower interface stress with a more uniform stress distribution than that implanted with a non-conformed cage. Additionally, intra-disc stress and facet loading at the adjacent segments were obviously increased in both groups C and N, especially those at the supra-jacent segments. However, stress increase was milder in group C than in group N for all directions of motion. Endplate-conformed cages can decrease cage-endplate interface stress in all directions of motion and increase cervical stability in FLE-EXT. Additionally, adjacent segments are possibly protected because intra-disc stress and facet loading are smaller after endplate-conformed cage implantation. However, axial stability was reduced in group C, indicating that endplate-conformed cage should not be used alone and an anterior plate system is still important in anterior cervical discectomy and fusion. © 2016 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

Automatic FDG-PET-based tumor and metastatic lymph node segmentation in cervical cancer

NASA Astrophysics Data System (ADS)

Arbonès, Dídac R.; Jensen, Henrik G.; Loft, Annika; Munck af Rosenschöld, Per; Hansen, Anders Elias; Igel, Christian; Darkner, Sune

2014-03-01

Treatment of cervical cancer, one of the three most commonly diagnosed cancers worldwide, often relies on delineations of the tumour and metastases based on PET imaging using the contrast agent 18F-Fluorodeoxyglucose (FDG). We present a robust automatic algorithm for segmenting the gross tumour volume (GTV) and metastatic lymph nodes in such images. As the cervix is located next to the bladder and FDG is washed out through the urine, the PET-positive GTV and the bladder cannot be easily separated. Our processing pipeline starts with a histogram-based region of interest detection followed by level set segmentation. After that, morphological image operations combined with clustering, region growing, and nearest neighbour labelling allow to remove the bladder and to identify the tumour and metastatic lymph nodes. The proposed method was applied to 125 patients and no failure could be detected by visual inspection. We compared our segmentations with results from manual delineations of corresponding MR and CT images, showing that the detected GTV lays at least 97.5% within the MR/CT delineations. We conclude that the algorithm has a very high potential for substituting the tedious manual delineation of PET positive areas.

Transoral Decompression and Anterior Stabilization of Atlantoaxial Joint in Patients with Basilar Impression and Chiari Malformation Type I: A Technical Report of 2 Clinical Cases.

PubMed

Shkarubo, Alexey N; Kuleshov, Alexander A; Chernov, Ilia V; Vetrile, Marchel S

2017-06-01

Presentation of clinical cases involving successful anterior stabilization of the C1-C2 segment in patients with invaginated C2 odontoid process and Chiari malformation type I. Clinical case description. Two patients with C2 odontoid processes invagination and Chiari malformation type I were surgically treated using the transoral approach. In both cases, anterior decompression of the upper cervical region was performed, followed by anterior stabilization of the C1-C2 segment. In 1 of the cases, this procedure was performed after posterior decompression, which led to transient regression of neurologic symptoms. In both cases, custom-made cervical plates were used for anterior stabilization of the C1-C2 segment. During the follow-up period of more than 2 years, a persistent regression of both the neurologic symptoms and Chiari malformation was observed. Anterior decompression followed by anterior stabilization of the C1-C2 segment is a novel and promising approach to treating Chiari malformation type I in association with C2 odontoid process invagination. Copyright © 2017 Elsevier Inc. All rights reserved.

Gravity Maps of Antarctic Lithospheric Structure from Remote-Sensing and Seismic Data

NASA Astrophysics Data System (ADS)

Tenzer, Robert; Chen, Wenjin; Baranov, Alexey; Bagherbandi, Mohammad

2018-02-01

Remote-sensing data from altimetry and gravity satellite missions combined with seismic information have been used to investigate the Earth's interior, particularly focusing on the lithospheric structure. In this study, we use the subglacial bedrock relief BEDMAP2, the global gravitational model GOCO05S, and the ETOPO1 topographic/bathymetric data, together with a newly developed (continental-scale) seismic crustal model for Antarctica to compile the free-air, Bouguer, and mantle gravity maps over this continent and surrounding oceanic areas. We then use these gravity maps to interpret the Antarctic crustal and uppermost mantle structure. We demonstrate that most of the gravity features seen in gravity maps could be explained by known lithospheric structures. The Bouguer gravity map reveals a contrast between the oceanic and continental crust which marks the extension of the Antarctic continental margins. The isostatic signature in this gravity map confirms deep and compact orogenic roots under the Gamburtsev Subglacial Mountains and more complex orogenic structures under Dronning Maud Land in East Antarctica. Whereas the Bouguer gravity map exhibits features which are closely spatially correlated with the crustal thickness, the mantle gravity map reveals mainly the gravitational signature of the uppermost mantle, which is superposed over a weaker (long-wavelength) signature of density heterogeneities distributed deeper in the mantle. In contrast to a relatively complex and segmented uppermost mantle structure of West Antarctica, the mantle gravity map confirmed a more uniform structure of the East Antarctic Craton. The most pronounced features in this gravity map are divergent tectonic margins along mid-oceanic ridges and continental rifts. Gravity lows at these locations indicate that a broad region of the West Antarctic Rift System continuously extends between the Atlantic-Indian and Pacific-Antarctic mid-oceanic ridges and it is possibly formed by two major fault segments. Gravity lows over the Transantarctic Mountains confirms their non-collisional origin. Additionally, more localized gravity lows closely coincide with known locations of hotspots and volcanic regions (Marie Byrd Land, Balleny Islands, Mt. Erebus). Gravity lows also suggest a possible hotspot under the South Orkney Islands. However, this finding has to be further verified.

Upper extremity palsy following cervical decompression surgery results from a transient spinal cord lesion.

PubMed

Hasegawa, Kazuhiro; Homma, Takao; Chiba, Yoshikazu

2007-03-15

Retrospective analysis. To test the hypothesis that spinal cord lesions cause postoperative upper extremity palsy. Postoperative paresis, so-called C5 palsy, of the upper extremities is a common complication of cervical surgery. Although there are several hypotheses regarding the etiology of C5 palsy, convincing evidence with a sufficient study population, statistical analysis, and clear radiographic images illustrating the nerve root impediment has not been presented. We hypothesized that the palsy is caused by spinal cord damage following the surgical decompression performed for chronic compressive cervical disorders. The study population comprised 857 patients with chronic cervical cord compressive lesions who underwent decompression surgery. Anterior decompression and fusion was performed in 424 cases, laminoplasty in 345 cases, and laminectomy in 88 cases. Neurologic characteristics of patients with postoperative upper extremity palsy were investigated. Relationships between the palsy, and patient sex, age, diagnosis, procedure, area of decompression, and preoperative Japanese Orthopaedic Association score were evaluated with a risk factor analysis. Radiographic examinations were performed for all palsy cases. Postoperative upper extremity palsy occurred in 49 cases (5.7%). The common features of the palsy cases were solely chronic compressive spinal cord disorders and decompression surgery to the cord. There was no difference in the incidence of palsy among the procedures. Cervical segments beyond C5 were often disturbed with frequent multiple segment involvement. There was a tendency for spontaneous improvement of the palsy. Age, decompression area (anterior procedure), and diagnosis (ossification of the posterior longitudinal ligament) are the highest risk factors of the palsy. The results of the present study support our hypothesis that the etiology of the palsy is a transient disturbance of the spinal cord following a decompression procedure. It appears to be caused by reperfusion after decompression of a chronic compressive lesion of the cervical cord. We recommend that physicians inform patients and surgeons of the potential risk of a spinal cord deficit after cervical decompression surgery.

Adjacent-level arthroplasty following cervical fusion.

PubMed

Rajakumar, Deshpande V; Hari, Akshay; Krishna, Murali; Konar, Subhas; Sharma, Ankit

2017-02-01

OBJECTIVE Adjacent-level disc degeneration following cervical fusion has been well reported. This condition poses a major treatment dilemma when it becomes symptomatic. The potential application of cervical arthroplasty to preserve motion in the affected segment is not well documented, with few studies in the literature. The authors present their initial experience of analyzing clinical and radiological results in such patients who were treated with arthroplasty for new or persistent arm and/or neck symptoms related to neural compression due to adjacent-segment disease after anterior cervical discectomy and fusion (ACDF). METHODS During a 5-year period, 11 patients who had undergone ACDF anterior cervical discectomy and fusion (ACDF) and subsequently developed recurrent neck or arm pain related to adjacent-level cervical disc disease were treated with cervical arthroplasty at the authors' institution. A total of 15 devices were implanted (range of treated levels per patient: 1-3). Clinical evaluation was performed both before and after surgery, using a visual analog scale (VAS) for pain and the Neck Disability Index (NDI). Radiological outcomes were analyzed using pre- and postoperative flexion/extension lateral radiographs measuring Cobb angle (overall C2-7 sagittal alignment), functional spinal unit (FSU) angle, and range of motion (ROM). RESULTS There were no major perioperative complications or device-related failures. Statistically significant results, obtained in all cases, were reflected by an improvement in VAS scores for neck/arm pain and NDI scores for neck pain. Radiologically, statistically significant increases in the overall lordosis (as measured by Cobb angle) and ROM at the treated disc level were observed. Three patients were lost to follow-up within the first year after arthroplasty. In the remaining 8 cases, the duration of follow-up ranged from 1 to 3 years. None of these 8 patients required surgery for the same vertebral level during the follow-up period. CONCLUSIONS Artificial cervical disc replacement in patients who have previously undergone cervical fusion surgery appears to be safe, with encouraging early clinical results based on this small case series, but more data from larger numbers of patients with long-term follow-up are needed. Arthroplasty may provide an additional tool for the management of post-fusion adjacent-level cervical disc disease in carefully selected patients.

Functional MR imaging of the spinal cord in cervical spinal cord injury patients by acupuncture at LI 4 (Hegu) and LI 11(Quchi).

PubMed

Chen, Y X; Kong, K M; Wang, W D; Xie, C H; Wu, R H

2007-01-01

To investigate the cervical spinal cord mapping on acupuncture at LI 4 (Hegu) and LI 11 (Quchi) by using 'Signal Enhancement by Extravascular water Protons' (SEEP)-fMRI, and to establish the response of using acupuncture in the cervical spinal cord. This research may provide some laboratory evidences from the acupuncture treatment on the cervical spinal cord of injuried patients. Seven healthy volunteers (healthy group) and three cervical spinal cord injury patients (injury group) were underwent low-frequency electrical stimulation at LI 4 and LI 11. Meanwhile, a single-shot fast spin-echo (SSFSE) sequence was used to perform functional MR imaging on a 1.5 T GE Signa MR system. The signals from the cervical spinal cord activated was measured both in sagittal and transverse imaging planes and then analyzed by AFNI (Analysis of Functional Neuroimages) system. It was found that in the sagittal view, two groups had an fMRI response in the cervical spinal cord after given acupuncture treatments at LI 4 and LI 11. The localizations of the segmental fMRI activation were focused at C6 and C2 cervical spinal cord level. In the transverse imaging plane, significant fMRI responses could be measured from the four of seven healthy volunteers and from two of three cervical spinal cord injury patients. They were located at C6/7 segments. The cross-sectional localization of the activity measured in the spinal cord was most in terms of the ipsilateral posterior direction. The signal amplitude varied mainly between 6.8%17.8%. However, the difference found between the two groups had no statistical meaning. The fMRI technique had detected an activation focused at C6 and C2 cervical spinal cord levels by use of acupuncture at LI 4 and LI 11 on a 1.5T GE clinical system. This proved that the meridians and points are found to be in existence. The fMRI can be used as a harmless research method to discuss the mechanisms of acupuncture as well as study the mechanisms of spinal cord diseases. It can be used to direct or monitor the related therapy on the spinal cord injury patients.

[Anatomic foundation of the lateral portal for radiotherapy of nasopharyngeal cancer (NPC)].

PubMed

Wei, B Q; Feng, P B; Li, J Z

1987-05-01

Basing on 31 normal skulls, the lateral projections of some points relative to the bony structure near the nasopharynx were located under the simulator, followed by drawing it on a sheet of paper with the aid of geometry and trigonometry. Thus, the relation between external and internal structures is shown on the drawn projection, which can serve as the anatomic basis for designing the routine field and improving radiotherapy technique. In the light of data informed by this study and clinical experiences of the authors and others, it was found logical, in radiotherapy of NPC, that large opposing lateral pre-auriculo-cervical portals with their posterior margin extending beyond the external auditory meatus posteriorly be used in order to avoid geographic miss of the uppermost deep cervical lymph nodes usually involved beneath the jugular foramen and posterior portion of the nasopharynx. In addition, the upper margin of the lateral portal must be parallel but superior to the cantho-auditory line, on which the foramen ovale is projected. Actual locating the upper margin should depend on the extent of the intracranial invasion of the tumor as shown by the CT scan.

The Efficacy of Intraoperative Neurophysiological Monitoring Using Transcranial Electrically Stimulated Muscle-evoked Potentials (TcE-MsEPs) for Predicting Postoperative Segmental Upper Extremity Motor Paresis After Cervical Laminoplasty.

PubMed

Fujiwara, Yasushi; Manabe, Hideki; Izumi, Bunichiro; Tanaka, Hiroyuki; Kawai, Kazumi; Tanaka, Nobuhiro

2016-05-01

Prospective study. To investigate the efficacy of transcranial electrically stimulated muscle-evoked potentials (TcE-MsEPs) for predicting postoperative segmental upper extremity palsy following cervical laminoplasty. Postoperative segmental upper extremity palsy, especially in the deltoid and biceps (so-called C5 palsy), is the most common complication following cervical laminoplasty. Some papers have reported that postoperative C5 palsy cannot be predicted by TcE-MsEPs, although others have reported that it can be predicted. This study included 160 consecutive cases that underwent open-door laminoplasty, and TcE-MsEP monitoring was performed in the biceps brachii, triceps brachii, abductor digiti minimi, tibialis anterior, and abductor hallucis. A >50% decrease in the wave amplitude was defined as an alarm point. According to the monitoring alarm, interventions were performed, which include steroid administration, foraminotomies, etc. Postoperative deltoid and biceps palsy occurred in 5 cases. Among the 155 cases without segmental upper extremity palsy, there were no monitoring alarms. Among the 5 deltoid and biceps palsy cases, 3 had significant wave amplitude decreases in the biceps during surgery, and palsy occurred when the patients awoke from anesthesia (acute type). In the other 2 cases in which the palsy occurred 2 days after the operation (delayed type), there were no significant wave decreases. In all of the cases, the palsy was completely resolved within 6 months. The majority of C5 palsies have been reported to occur several days after surgery, but some of them have been reported to occur immediately after surgery. Our results demonstrated that TcE-MsEPs can predict the acute type, whereas the delayed type cannot be predicted. A >50% wave amplitude decrease in the biceps is useful to predict acute-type segmental upper extremity palsy. Further examination about the interventions for monitoring alarm will be essential for preventing palsy.

Etiology and treatment of amyotrophic lateral sclerosis

PubMed Central

Rafael, Hernando; David, Juan Oscar; Vilca, Antonio Santiago

2017-01-01

Background: To date all researchers conclude that the etiology of Amyotrophic lateral sclerosis (ALS) is not known. On the contrary, since August 2009, we believe that disease is of ischemic origin in the anterior surface of the medulla oblongata. Material and method: We present our surgical experience into 45 patients with ALS (bulbar form in 36 cases and spinal form in 9). Preoperative MRI scans revealed microinfarcts in the medulla oblongata and/or cervical cord. During surgery we found: 1) poor quality of omentum in most cases; 2) degenerative changes in the cervical spine; 3) anatomical anomalies at the V4 segments of the vertebral arteries; 4) moderate to severe atherosclerosis at both V4 segments; 5) unilateral absence or stenosis in the anterior-ventral spinal arteries (AVSAs). All patients received omentum on the anterior, lateral and posterior surface of the medulla oblongata, and in 9 cases, an additional segment at the C5-C6 level. Results: Neurological improvement was better during the first days or weeks after surgery than in the following months or years, in all patients. However, 13 patients suffered neurological impairment in about 4 months later, due to greater deterioration of the cervical spine, by contrast, 7 patients with mild ALS have experienced neurological improvement by 80 to 100% during a follow-up of 4 and 6 years. Conclusions: These results confirm that ALS is of ischemic origin in the intraparenchymal territory of the AVSAs and/or in anterior spinal artery caused by atherosclerosis and associated to anatomical variants in the V4 segments of the vertebral arteries. Because in contrast to this, its revascularization by means of omentum can cure (mild degree) or improve this disease. PMID:28533943

Etiology and treatment of amyotrophic lateral sclerosis.

PubMed

Rafael, Hernando; David, Juan Oscar; Vilca, Antonio Santiago

2017-01-01

To date all researchers conclude that the etiology of Amyotrophic lateral sclerosis (ALS) is not known. On the contrary, since August 2009, we believe that disease is of ischemic origin in the anterior surface of the medulla oblongata. We present our surgical experience into 45 patients with ALS (bulbar form in 36 cases and spinal form in 9). Preoperative MRI scans revealed microinfarcts in the medulla oblongata and/or cervical cord. During surgery we found: 1) poor quality of omentum in most cases; 2) degenerative changes in the cervical spine; 3) anatomical anomalies at the V4 segments of the vertebral arteries; 4) moderate to severe atherosclerosis at both V4 segments; 5) unilateral absence or stenosis in the anterior-ventral spinal arteries (AVSAs). All patients received omentum on the anterior, lateral and posterior surface of the medulla oblongata, and in 9 cases, an additional segment at the C5-C6 level. Neurological improvement was better during the first days or weeks after surgery than in the following months or years, in all patients. However, 13 patients suffered neurological impairment in about 4 months later, due to greater deterioration of the cervical spine, by contrast, 7 patients with mild ALS have experienced neurological improvement by 80 to 100% during a follow-up of 4 and 6 years. These results confirm that ALS is of ischemic origin in the intraparenchymal territory of the AVSAs and/or in anterior spinal artery caused by atherosclerosis and associated to anatomical variants in the V4 segments of the vertebral arteries. Because in contrast to this, its revascularization by means of omentum can cure (mild degree) or improve this disease.

The application of a new type of titanium mesh cage in hybrid anterior decompression and fusion technique for the treatment of continuously three-level cervical spondylotic myelopathy.

PubMed

Liu, Xiaowei; Chen, Yu; Yang, Haisong; Li, Tiefeng; Xu, Haidong; Xu, Bin; Chen, Deyu

2017-01-01

To evaluate the efficacy and safety of a new type of titanium mesh cage (NTMC) in hybrid anterior decompression and fusion method (HDF) in treating continuously three-level cervical spondylotic myelopathy (TCSM). Ninety-four cases who had TCSM and accepted the HDF from Jan 2007 to Jan 2010 were included. Clinical and radiological outcomes were compared between cases who had the NTMC (Group A, n = 45) and traditional titanium mesh cage (TTMC, Group B, n = 49) after corpectomies. Each case accepted one polyetheretherketone cage (PEEK) after discectomy. Mean follow-up were 74.4 and 77.3 months in Group A and B, respectively (p > 0.05). Differences in cervical lordosis (CL), segmental lordosis (SL), anterior segmental height (ASH) and posterior segmental height (PSH) between two groups were not significant preoperatively, 3-days postoperatively or at final visit. However, losses of the CL, SL, ASH and PSH were all significantly larger in Group B at the final visit, so did incidences of segmental subsidence and severe subsidence. Difference in preoperative Japanese Orthopedic Association (JOA), visual analog scale (VAS), neck disability index (NDI) or SF-36 between two groups was not significant. At the final visit, fusion rate, JOA, and SF-36 were all comparable between two groups, but the VAS and NDI were both significantly greater in Group B. For cases with TCSM, HDF with the NTMC and TTMC can provide comparable radiological and clinical improvements. But application of the NTMC in HDF is of advantages in decreasing the subsidence incidence, losses of lordosis correction, VAS and NDI.

Functional MR imaging of the cervical spinal cord by use of electrical stimulation at LI4 (Hegu).

PubMed

Wang, W D; Kong, K M; Xiao, Y Y; Wang, X J; Liang, B; Qi, W L; Wu, R H

2006-01-01

The purpose is to investigate the cervical spinal cord mapping on electrical stimulation at LI4 (Hegu) by using 'signal enhancement by extravascular water protons' (SEEP)-fMRI, and to establish the response of acupoint-stimulation in spinal cord. Three healthy volunteers were underwent low-frequency electrical stimulation at LI4. Meanwhile, a single-shot fast spin-echo (SSFSE) sequence was used to perform functional MR imaging on a 1.5 T GE Signa MR system. Cord activation was measured both in the sagittal and transverse imaging planes and then analyzed by AFNI (analysis of functional neuroimages) system. In the sagittal view, two subjects had an fMRI response in the cervical spinal cord upon electrical stimulation at LI4. The localizations of the segmental fMRI activation are both at C6 through T1 and C2/3 cervical spinal cord level. In the transverse imaging plane, significant fMRI responses could be measured in the last subjects locating at C6/7 segment, the cross-sectional localization of the activity measured in the spinal cord was most in terms of the ipsilateral posterior direction. It is concluded that the fMRI technique can be used for detecting with activity in the human cervical spinal cord by a single-shot fast spin-echo sequence on a 1.5 T GE clinical system. Investigating the acupoint-stimulation response in the spinal cord using the spinal fMRI will be helpful for the further discussion on the mechanisms of acupuncture to spinal cord diseases.

Cervical spine disc prosthesis: radiographic, biomechanical and morphological post mortal findings 12 weeks after implantation. A retrieval example.

PubMed

Pitzen, Tobias; Kettler, Annette; Drumm, Joerg; Nabhan, Abdullah; Steudel, Wolf Ingo; Claes, Lutz; Wilke, Hans Joachim

2007-07-01

There is a gap between in vitro and clinical studies concerning performance of spinal disc prosthesis. Retrieval studies may help to bridge this gap by providing more detailed information about motion characteristics, wear properties and osseous integration. Here, we report on the radiographic, mechanical, histological properties of a cervical spine segment treated with a cervical spine disc prosthesis (Prodisc C, Synthes Spine, Paoli, USA) for 3 months. A 48-year-old male received the device due to symptomatic degenerative disc disease within C5-C6. The patient recovered completely from his symptoms. Twelve weeks later, he died from a subarachnoid hemorrhage. During routine autopsy, C3-T1 was removed with all attached muscles and ligaments and subjected to plain X-rays and computed tomography, three dimensional flexibility tests, shear test as well as histological and electronic microscopic investigations. We detected radiolucencies mainly at the cranial interface between bone and implant. The flexibility of the segment under pure bending moments of +/-2.5 Nm applied in flexion/extension, axial rotation and lateral bending was preserved, with, however, reduced lateral bending and enlarged neutral zone compared to the adjacent segments C4-C5, and C6-C7. Stepwise increase of loading in flexion/extension up to +/-9.5 Nm did not result in segmental destruction. A postero-anterior force of 146 N was necessary to detach the lower half of the prosthesis from the vertebra. At the polyethylene (PE) core, signs of wear were observed compared to an unused core using electronic microscopy. Metal and PE debris without signs of severe inflammatory reaction was found within the surrounding soft tissue shell of the segment. A thin layer of soft connective tissue covered the major part of the implant endplate. Despite the limits of such a case report, the results show: that such implants are able to preserve at least a certain degree of segmental flexibility, that direct bone implant contact is probably rare, and that debris may be found after 12 weeks.

Cervical Spine Stiffness and Geometry of the Young Human Male

DTIC Science & Technology

1982-11-01

angle of zero degrees, i.e., the well-known vertical apposition of facets in the thoracic and lumbar area; d) The cervical articular facet areas are...were used by Rolander (1966) and White (1969) to study the motion segments of the lumbar and thoracic spines, respectively. When forces and moments are...unaer axial tension and compression as well as bending with axial load, Evans and Lissner (1959) gave load-deflection curves for the lumbar spine in

Compressive cervical pannus formation in a patient after 2-level disc arthroplasty: a rare complication treated with posterior instrumented fusion.

PubMed

Brophy, Carl M; Hoh, Daniel J

2018-06-01

Cervical disc arthroplasty (CDA) has received widespread attention as an alternative to anterior fusion due to its similar neurological and functional improvement, with the advantage of preservation of segmental motion. As CDA becomes more widely implemented, the potential for unexpected device-related adverse events may be identified. The authors report on a 48-year-old man who presented with progressive neurological deficits 3 years after 2-level CDA was performed. Imaging demonstrated periprosthetic osteolysis of the vertebral endplates at the CDA levels, with a heterogeneously enhancing ventral epidural mass compressing the spinal cord. Diagnostic workup for infectious and neoplastic processes was negative. The presumptive diagnosis was an inflammatory pannus formation secondary to abnormal motion at the CDA levels. Posterior cervical decompression and instrumented fusion was performed without removal of the arthroplasty devices or the ventral epidural mass. Postoperative imaging at 2 months demonstrated complete resolution of the compressive pannus, with associated improvement in clinical symptoms. Follow-up MRI at > 6 months showed no recurrence of the pannus. At 1 year postoperatively, CT scanning revealed improvement in periprosthetic osteolysis. Inflammatory pannus formation may be an unexpected complication of abnormal segmental motion after CDA. This rare etiology of an epidural mass associated with an arthroplasty device should be considered, in addition to workup for other potential infectious or neoplastic mass lesions. In symptomatic individuals, compressive pannus lesions can be effectively treated with fusion across the involved segment without removal of the device.

HOXB homeobox gene expression in cervical carcinoma.

PubMed

López, R; Garrido, E; Piña, P; Hidalgo, A; Lazos, M; Ochoa, R; Salcedo, M

2006-01-01

The homeobox (HOX) genes are a family of transcription factors that bind to specific DNA sequences in target genes regulating gene expression. Thirty-nine HOX genes have been mapped in four conserved clusters: A, B, C, and D; they act as master genes regulating the identity of body segments along the anteroposterior axis of the embryo. The role played by HOX genes in adult cell differentiation is unclear to date, but growing evidence suggests that they may play an important role in the development of cancer. To study the role played by HOX genes in cervical cancer, in the present work, we analyzed the expression of HOXB genes and the localization of their transcripts in human cervical tissues. Reverse transcription-polymerase chain reaction analysis and nonradioactive RNA in situ hybridization were used to detect HOXB expression in 11 normal cervical tissues and 17 cervical carcinomas. It was determined that HOXB1, B3, B5, B6, B7, B8, and B9 genes are expressed in normal adult cervical epithelium and squamous cervical carcinomas. Interestingly, HOXB2, HOXB4, and HOXB13 gene expression was found only in tumor tissues. Our findings suggest that the new expression of HOXB2, HOXB4, and B13 genes is involved in cervical cancer.

Surgery for failed cervical spine reconstruction.

PubMed

Helgeson, Melvin D; Albert, Todd J

2012-03-01

Review article. To review the indications, operative strategy, and complications of revision cervical spine reconstruction. With many surgeons expanding their indications for cervical spine surgery, the number of patients being treated operatively has increased. Unfortunately, the number of patients requiring revision procedures is also increasing, but very little literature exists reviewing changes in the indications or operative planning for revision reconstruction. Narrative and review of the literature. In addition to the well-accepted indications for primary cervical spine surgery (radiculopathy, myelopathy, instability, and tumor), we have used the following indications for revision surgery: pseudarthrosis, adjacent segment degeneration, inadequate decompression, iatrogenic instability, and deformity. Our surgical goal for pseudarthrosis is obviously to obtain a fusion, which can usually be performed with an approach not done previously. Our surgical goals for instability and deformity are more complex, with a focus on decompression of any neurologic compression, correction of deformity, and stability. Revision cervical spine reconstruction is safe and effective if performed for the appropriate indications and with proper planning.

Development of Ultrasound to Measure In-vivo Dynamic Cervical Spine Intervertebral Disc Mechanics

DTIC Science & Technology

2014-01-01

The deformation between C4 and C6 measured by the US probe was affected by bulging of the IVD and soft tissues during compressive loading as...endplates of the vertebrae and cartilaginous endplate of the discs were added to all segments. Figure 28 Coronal views of the updated C4-T1 FEM (a...the ligaments and soft tissue connections that provide stability to the cervical spine FSUs were added (Figures 30 and 31). For the anterior

Atlanto-axial approach for cervical myelography in a Thoroughbred horse with complete fusion of the atlanto-occipital bones

PubMed Central

Aleman, Monica; Dimock, Abigail N.; Wisner, Erik R.; Prutton, Jamie W.; Madigan, John E.

2014-01-01

A 2-year-old Thoroughbred gelding with clinical signs localized to the first 6 spinal cord segments (C1 to C6) had complete fusion of the atlanto-occipital bones which precluded performing a routine myelogram. An ultrasound-assisted myelogram at the intervertebral space between the atlas and axis was successfully done and identified a marked extradural compressive myelopathy at the level of the atlas and axis, and axis and third cervical vertebrae. PMID:25392550

Outcomes following cervical disc arthroplasty: a retrospective review.

PubMed

Cody, John P; Kang, Daniel G; Tracey, Robert W; Wagner, Scott C; Rosner, Michael K; Lehman, Ronald A

2014-11-01

Cervical disc arthroplasty has emerged as a viable technique for the treatment of cervical radiculopathy and myelopathy, with the proposed benefit of maintenance of segmental range of motion. There are relatively few, non-industry sponsored studies examining the outcomes and complications of cervical disc arthroplasty. Therefore, we set out to perform a single center evaluation of the outcomes and complications of cervical disc arthroplasty. We performed a retrospective review of all patients from a single military tertiary medical center undergoing cervical disc arthroplasty from August 2008 to August 2012. The clinical outcomes and complications associated with the procedure were evaluated. A total of 219 consecutive patients were included in the review, with an average follow-up of 11.2 (±11.0)months. Relief of pre-operative symptoms was noted in 88.7% of patients, and 92.2% of patients were able to return to full pre-operative activity. There was a low rate of complications related to the anterior cervical approach (3.2% with recurrent laryngeal nerve injury, 8.9% with dysphagia), with no device/implant related complications. Symptomatic cervical radiculopathy is a common problem in both the civilian and active duty military populations and can cause significant disability leading to loss of work and decreased operational readiness. There exist several surgical treatment options for appropriately indicated patients. Based on our findings, cervical disc arthroplasty is a safe and effective treatment for symptomatic cervical radiculopathy and myelopathy, with a low incidence of complications and high rate of symptom relief. Published by Elsevier Ltd.

Biomechanical Stability of a Stand-Alone Interbody Spacer in Two-Level and Hybrid Cervical Fusion Constructs.

PubMed

Kang, Daniel G; Wagner, Scott C; Tracey, Robert W; Cody, John P; Gaume, Rachel E; Lehman, Ronald A

2017-10-01

In vitro human cadaveric biomechanical analysis. To evaluate the segmental stability of a stand-alone spacer (SAS) device compared with the traditional anterior cervical plate (ACP) construct in the setting of a 2-level cervical fusion construct or as a hybrid construct adjacent to a previous 1-level ACP construct. Twelve human cadaveric cervical spines (C2-T1) were nondestructively tested with a custom 6-degree-of-freedom spine simulator under axial rotation (AR), flexion-extension (FE), and lateral bending (LB) at 1.5 N m loads. After intact analysis, each specimen underwent instrumentation and testing in the following 3 configurations, with each specimen randomized to the order of construct: (A) C5-7 SAS; (B) C5-6 ACP, and C6-7 SAS (hybrid); (C) C5-7 ACP. Full range of motion (ROM) data at C5-C7 was obtained and analyzed by each loading modality utilizing mean comparisons with repeated measures analysis of variance with Sidak correction for multiple comparisons. Compared with the intact specimen, all tested constructs had significantly increased segmental stability at C5-C7 in AR and FE ROM, with no difference in LB ROM. At C5-C6, all test constructs again had increased segmental stability in FE ROM compared with intact (10.9° ± 4.4° Intact vs SAS 6.6° ± 3.2°, P < .001; vs.Hybrid 2.9° ± 2.0°, P = .005; vs ACP 2.1° ± 1.4°, P < .001), but had no difference in AR and LB ROM. Analysis of C6-C7 ROM demonstrated all test groups had significantly greater segmental stability in FE ROM compared with intact (9.6° ± 2.7° Intact vs SAS 5.0° ± 3.0°, P = .018; vs Hybrid 5.0° ± 2.7°, P = .018; vs ACP 4.4° ± 5.2°, P = .005). Only the hybrid and 2-level ACP constructs had increased stability at C6-C7 in AR ROM compared with intact, with no difference for all test groups in LB ROM. Comparison between test constructs demonstrated no difference in C5-C7 and C6-C7 segmental stability in all planes of motion. However, at C5-C6 comparison between test constructs found the 2-level SAS had significantly less segmental stability compared to the hybrid (6.6° ± 3.2° vs 2.9° ± 2.0°, P = .025) and ACP (6.6° ± 3.2° vs 2.1° ± 1.4°, P = .004). Our study found the currently tested SAS device may be a reasonable option as part of a 2-level hybrid construct, when used below an adjacent 1-level ACP, but should be used with careful consideration as a 2-level SAS construct. Consequences of decreased segmental stability in FE are unknown; however, optimal immediate fixation stability is an important surgical principle to avoid loss of fixation, segmental kyphosis, interbody graft subsidence, and pseudarthrosis.

[Our experience with the use of Active-C cervical prosthesis].

PubMed

Misik, Ferenc; Böösi, Martina; Papp, Zoltán; Padányi, Csaba; Banczerowski, Péter

2016-09-30

The most widely used surgical procedure in the treatment of cervical spine disc hernias have been the anterior cervical discectomy and fusion for decades. The usage of cervical disc prostheses enabled us to preserve the movements of the affected segments, hereby reducing the overexertion of the adjacent vertebrae and discs. Our goal is to follow our patients operated with Active-C prosthesis (which is used in the Institute since 2010) to gather information about the change of their complaints and about the functioning and unwanted negative effects of the prostheses. Question - Is the usage of Active-C prosthesis an efficient procedure? Between 2010 and 2013, performing the survey of neurological conditions and functional X-ray examinations. We measured the complaints of the patients using the Visual Analogue Scale, Neck Disability Index and Cervical Spine Outcomes Questionnaire. The control group consisted of patients who were operated in one segment using the fusion technique. In the study group according to the Neck Disability Index scale after 18 months, seven patients had no complaints, while twelve persons reported mild and the remaining six moderate complaints. In the control group, moderate complaints were present in four patients, while twelve patients reported mild complaints. The other eight persons showed no complaints. According to the results of the Visual Analogue Scale in the group of prosthesis, the degree of referred pain decreased from 8.6 to 1.84 one and a half years after the surgery. A decrease was observable in the case of axial pain too, from 6.6 down to 1.92 (p<0.01). In case of three from the twenty-five patients there was no sign of movement in the level of the prosthesis. According to the present short- and mediumterm studies, the usage of the cervical disc prosthesis can be considered as an efficient procedure, but at the same time the advantages can only be determined in the long run, therefore further following and studies are required.

Cervical arthroplasty for moderate to severe disc degeneration: clinical and radiological assessments after a minimum follow-up of 18 months--Pfirrmann grade and cervical arthroplasty.

PubMed

Oh, Chang Hyun; Kim, Do Yeon; Ji, Gyu Yeul; Kim, Yeo Ju; Yoon, Seung Hwan; Hyun, Dongkeun; Kim, Eun Young; Park, Hyeonseon; Park, Hyeong-Chun

2014-07-01

Clinical outcomes and radiologic results after cervical arthroplasty have been reported in many articles, yet relatively few studies after cervical arthroplasty have been conducted in severe degenerative cervical disc disease. Sixty patients who underwent cervical arthroplasty (Mobi-C®) between April 2006 and November 2011 with a minimum follow-up of 18 months were enrolled in this study. Patients were divided into two groups according to Pfirrmann classification on preoperative cervical MR images: group A (Pfirrmann disc grade III, n=38) and group B (Pfirrmann disc grades IV or V, n=22). Visual analogue scale (VAS) scores of neck and arm pain, modified Oswestry Disability Index (mODI) score, and radiological results including cervical range of motion (ROM) were assessed before and after surgery. VAS and mean mODI scores decreased after surgery from 5.1 and 57.6 to 2.7 and 31.5 in group A and from 6.1 and 59.9 to 3.7 and 38.4 in group B, respectively. In both groups, VAS and mODI scores significantly improved postoperatively (p<0.001), although no significant intergroup differences were found. Also, cervical dynamic ROM was preserved or gradually improved up to 18 months after cervical arthroplasty in both groups. Global, segmental and adjacent ROM was similar for both groups during follow-up. No cases of device subsidence or extrusion were recorded. Clinical and radiological results following cervical arthroplasty in patients with severe degenerative cervical disc disease were no different from those in patients with mild degenerative cervical disc disease after 18 months of follow-up.

Biomechanical Analysis of Cervical Disc Replacement and Fusion Using Single Level, Two Level, and Hybrid Constructs.

PubMed

Gandhi, Anup A; Kode, Swathi; DeVries, Nicole A; Grosland, Nicole M; Smucker, Joseph D; Fredericks, Douglas C

2015-10-15

A biomechanical study comparing arthroplasty with fusion using human cadaveric C2-T1 spines. To compare the kinematics of the cervical spine after arthroplasty and fusion using single level, 2 level and hybrid constructs. Previous studies have shown that spinal levels adjacent to a fusion experience increased motion and higher stress which may lead to adjacent segment disc degeneration. Cervical arthroplasty achieves similar decompression but preserves the motion at the operated level, potentially decreasing the occurrence of adjacent segment disc degeneration. 11 specimens (C2-T1) were divided into 2 groups (BRYAN and PRESTIGE LP). The specimens were tested in the following order; intact, single level total disc replacement (TDR) at C5-C6, 2-level TDR at C5-C6-C7, fusion at C5-C6 and TDR at C6-C7 (Hybrid construct), and lastly a 2-level fusion. The intact specimens were tested up to a moment of 2.0 Nm. After each surgical intervention, the specimens were loaded until the primary motion (C2-T1) matched the motion of the respective intact state (hybrid control). An arthroplasty preserved motion at the implanted level and maintained normal motion at the nonoperative levels. Arthrodesis resulted in a significant decrease in motion at the fused level and an increase in motion at the unfused levels. In the hybrid construct, the TDR adjacent to fusion preserved motion at the arthroplasty level, thereby reducing the demand on the other levels. Cervical disc arthroplasty with both the BRYAN and PRESTIGE LP discs not only preserved the motion at the operated level, but also maintained the normal motion at the adjacent levels. Under simulated physiologic loading, the motion patterns of the spine with the BRYAN or PRESTIGE LP disc were very similar and were closer than fusion to the intact motion pattern. An adjacent segment disc replacement is biomechanically favorable to a fusion in the presence of a pre-existing fusion.

Vertebral formula and congenital abnormalities of the vertebral column in rabbits.

PubMed

Proks, P; Stehlik, L; Nyvltova, I; Necas, A; Vignoli, M; Jekl, V

2018-06-01

The aim of this retrospective study of 330 rabbits (164 males, 166 females) was to determine different vertebral formulas and prevalence of congenital vertebral anomalies in rabbits from radiographs of the cervical (C), thoracic (Th), lumbar (L) and sacral (S) segments of the vertebral column. The number of vertebrae in each segment of vertebral column, position of anticlinal vertebra and localisation and type of congenital abnormalities were recorded. In 280/330 rabbits (84.8%) with normal vertebral morphology, seven vertebral formulas were identified: C7/Th12/L7/S4 (252/330, 76.4%), C7/Th12/L6/S4 (11/330, 3.3%), C7/Th13/L7/S4 (8/330, 2.4%), C7/Th12/L7/S5 (4/330, 1.2%), C7/Th12/L8/S4 (3/330, 0.9%), C7/Th12/L7/S6 (1/330, 0.3%) and C7/Th11/L7/S4 (1/330, 0.3%). The anticlinal vertebra was identified as Th10 in 56.4% of rabbits and Th11 in 42.4% of rabbits. Congenital spinal abnormalities were identified in 50/330 (15.2%) rabbits, predominantly as a single pathology (n=44). Transitional vertebrae represented the most common abnormalities (n=41 rabbits) in the thoracolumbar (n=35) and lumbosacral segments (n=6). Five variants of thoracolumbar transitional vertebrae were identified. Cervical butterfly vertebrae were detected in three rabbits. One rabbit exhibited three congenital vertebral anomalies: cervical block vertebra, thoracic hemivertebra and thoracolumbar transitional vertebra. Five rabbits exhibited congenital vertebral abnormalities with concurrent malalignment, specifically cervical kyphosis/short vertebra (n=1), thoracic lordoscoliosis/thoracolumbar transitional vertebrae (n=1), thoracic kyphoscoliosis/wedge vertebrae (n=2) and thoracolumbar lordoscoliosis/thoracolumbar transitional vertebrae/lumbosacral transitional vertebrae (n=1). These findings suggest that vertebral columns in rabbits display a wide range of morphologies, with occasional congenital malformations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Hydrothermal circulation at the Cleft-Vance overlapping spreading center: Results of a magnetometric resistivity survey

USGS Publications Warehouse

Evans, R.L.; Webb, S.C.; Jegen, M.; Sananikone, K.

1998-01-01

We report on a magnetometric resistivity sounding carried out in the overlapping spreading center between the Cleft and Vance segments of the Juan de Fuca Ridge. The data collected reveal a strong three dimensionality in the crustal electrical resistivity structure on wavelengths of a few kilometers. Areas of reduced crustal electrical resistivities, with values approaching that of seawater, are seen beneath the neovolcanic zones of both active spreading centers. We interpret these reduced resistivities as evidence of active hydrothermal circulation within the uppermost 1 km of hot, young oceanic crust.

Tensile failure properties of the perinatal, neonatal, and pediatric cadaveric cervical spine.

PubMed

Luck, Jason F; Nightingale, Roger W; Song, Yin; Kait, Jason R; Loyd, Andre M; Myers, Barry S; Bass, Cameron R Dale

2013-01-01

Biomechanical tensile testing of perinatal, neonatal, and pediatric cadaveric cervical spines to failure. To assess the tensile failure properties of the cervical spine from birth to adulthood. Pediatric cervical spine biomechanical studies have been few due to the limited availability of pediatric cadavers. Therefore, scaled data based on human adult and juvenile animal studies have been used to augment the limited pediatric cadaver data. Despite these efforts, substantial uncertainty remains in our understanding of pediatric cervical spine biomechanics. A total of 24 cadaveric osteoligamentous head-neck complexes, 20 weeks gestation to 18 years, were sectioned into segments (occiput-C2 [O-C2], C4-C5, and C6-C7) and tested in tension to determine axial stiffness, displacement at failure, and load-to-failure. Tensile stiffness-to-failure (N/mm) increased by age (O-C2: 23-fold, neonate: 22 ± 7, 18 yr: 504; C4-C5: 7-fold, neonate: 71 ± 14, 18 yr: 509; C6-C7: 7-fold, neonate: 64 ± 17, 18 yr: 456). Load-to-failure (N) increased by age (O-C2: 13-fold, neonate: 228 ± 40, 18 yr: 2888; C4-C5: 9-fold, neonate: 207 ± 63, 18 yr: 1831; C6-C7: 10-fold, neonate: 174 ± 41, 18 yr: 1720). Normalized displacement at failure (mm/mm) decreased by age (O-C2: 6-fold, neonate: 0.34 ± 0.076, 18 yr: 0.059; C4-C5: 3-fold, neonate: 0.092 ± 0.015, 18 yr: 0.035; C6-C7: 2-fold, neonate: 0.088 ± 0.019, 18 yr: 0.037). Cervical spine tensile stiffness-to-failure and load-to-failure increased nonlinearly, whereas normalized displacement at failure decreased nonlinearly, from birth to adulthood. Pronounced ligamentous laxity observed at younger ages in the O-C2 segment quantitatively supports the prevalence of spinal cord injury without radiographic abnormality in the pediatric population. This study provides important and previously unavailable data for validating pediatric cervical spine models, for evaluating current scaling techniques and animal surrogate models, and for the development of more biofidelic pediatric crash test dummies.

Comparison of two anterior fusion methods in two-level cervical spondylosis myelopathy: a meta-analysis

PubMed Central

Huang, Zhe-Yu; Wu, Ai-Min; Li, Qing-Long; Lei, Tao; Wang, Kang-Yi; Xu, Hua-Zi; Ni, Wen-Fei

2014-01-01

Objective The aim of this study was to evaluate the efficacy and safety of anterior cervical corpectomy and fusion (ACCF) and anterior cervical discectomy and fusion (ACDF) for treating two-adjacent-level cervical spondylosis myelopathy (CSM). Design A meta-analysis of the two anterior fusion methods was conducted. The electronic databases of PubMed, the Cochrane Central Register of Controlled Trials, ScienceDirect, CNKI, WANFANG DATA and CQVIP were searched. Quality assessment of the included studies was evaluated using the Cochrane Risk of Bias Tool and the Methodological Index for Non-Randomised Studies criteria. Pooled risk ratios of dichotomous outcomes and standardised mean differences (SMDs) of continuous outcomes were generated. Using the χ2 and I2 tests, the statistical heterogeneity was assessed. Subgroup and sensitivity analyses were also performed. Participants Nine eligible trials with a total of 631 patients and a male-to-female ratio of 1.38:1 were included in this meta-analysis. Inclusion criteria Randomised controlled trials (RCTs) and non-randomised controlled trials that adopted ACCF and ACDF to treat two-adjacent-level CSM were included. Results No significant differences were identified between the two groups regarding hospital stay, the Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) scores for neck and arm pain, total cervical range of motion (ROM), fusion ROM, fusion rate, adjacent-level ossification and complications, while ACDF had significantly less bleeding (SMD=1.14, 95% CI (0.74 to 1.53)); a shorter operation time (SMD=1.13, 95% CI (0.82 to 1.45)); greater cervical lordosis, total cervical (SMD=−2.95, 95% CI (−4.79 to −1.12)) and fused segment (SMD=−2.24, 95% CI (−3.31 to −1.17)); higher segmental height (SMD=−0.68, 95% CI (−1.03 to −0.34)) and less graft subsidence (SMD=0.40, 95% CI (0.06 to 0.75)) compared to ACCF. Conclusions The results suggested that ACDF has more advantages compared to ACCF. However, additional high-quality RCTs and a longer follow-up duration are needed. PMID:25031189

Cervical Disk Replacement With Discover Versus Fusion in a Single-Level Cervical Disk Disease: A Prospective Single-Center Randomized Trial With a Minimum 2-Year Follow-up.

PubMed

Rožanković, Marjan; Marasanov, Sergej M; Vukić, Miroslav

2017-06-01

Prospective randomized study. To compare the clinical outcome after Discover arthroplasty versus anterior cervical discectomy and fusion (ACDF) in patients treated for symptomatic single-level cervical disk disease. ACDF is still the gold standard for surgical treatment of cervical spine degenerative disk disease. However, results of many studies suggest that it may cause degenerative changes at levels immediately above and below the fusion, known as adjacent segment degenerative disease. Cervical arthroplasty has recently been introduced as an alternative to standard procedure of ACDF. It showed decreased surgical morbidity, decreased complications from postoperative immobilization, and an earlier return to previous level of function. A total of 105 consecutive patients with single-level cervical disk disease, producing radiculopathy and/or myelopathy were randomly divided into groups to undergo ACDF or Discover arthroplasty. All patients were evaluated with preoperative and postoperative serial radiographic studies and clinically, using Neck Disability Index, Visual Analog Scale and neurological status at 3, 6, 12, and 24 months. The results of our study indicate that cervical arthroplasty using Discover Artificial Cervical Disc provides favorable clinical and radiologic outcomes in a follow-up period of 24 months. There has been significant improvement in clinical parameters, Visual Analog Scale and Neck Disability Index, at 3, 6, 12, and 24 months in arthroplasty group comparing to control group. The Discover artificial cervical disc replacement offers favorable outcome compared with ACDF for a single-level cervical disk disease at short-term and long-term follow-up.

Preparation, property of the complex of carboxymethyl chitosan grafted copolymer with iodine and application of it in cervical antibacterial biomembrane.

PubMed

Chen, Yu; Yang, Yumin; Liao, Qingping; Yang, Wei; Ma, Wanfeng; Zhao, Jian; Zheng, Xionggao; Yang, Yang; Chen, Rui

2016-10-01

Cervical erosion is one of the common diseases of women. The loop electrosurgical excisional procedure (LEEP) has been used widely in the treatment of the cervical diseases. However, there are no effective wound dressings for the postoperative care to protect the wound area from further infection, leading to increased secretion and longer healing time. Iodine is a widely used inorganic antibacterial agent with many advantages. However, the carrier for stable iodine complex antibacterial agents is lack. In the present study, a novel iodine carrier, Carboxymethyl chitosan-g-(poly(sodium acrylate)-co-polyvinylpyrrolidone) (CMCTS-g-(PAANa-co-PVP), was prepared by graft copolymerization of sodium acrylate (AANa) and N-vinylpyrrolidone (NVP) to a carboxymethyl chitosan (CMCTS) skeleton. The obtained structure could combine prominent property of poly(sodium acrylate) (PAANa) anionic polyelectrolyte segment and good complex property of polyvinylpyrrolidone (PVP) segment to iodine. The bioactivity of CMCTS could also be kept. The properties of the complex, CMCTS-g-(PAANa-co-PVP)-I2, were studied. The in vitro experiment shows that it has broad-spectrum bactericidal effects to virus, fungus, gram-positive bacteria and gram-negative bacteria. A CMCTS-g-(PAANa-co-PVP)-I2 complex contained cervical antibacterial biomembrane (CABM) was prepared. The iodine release from the CABM is pH-dependent. The clinic trial results indicate that CABM has better treatment effectiveness than the conventional treatment in the postoperative care of the LEEP operation. Copyright © 2016 Elsevier B.V. All rights reserved.

A Longitudinal Study of the Six Degrees of Freedom Cervical Spine Range of Motion During Dynamic Flexion/Extension and Rotation After Single-Level Anterior Arthrodesis

PubMed Central

Anderst, William J.; West, Tyler; Donaldson, William F; Lee, Joon Y.; Kang, James D.

2016-01-01

Study Design A longitudinal study using biplane radiography to measure in vivo intervertebral range of motion (ROM) during dynamic flexion/extension and rotation. Objective To longitudinally compare intervertebral maximal ROM and midrange motion in asymptomatic control subjects and single-level arthrodesis patients. Summary of Background Data In vitro studies consistently report that adjacent segment maximal ROM increases superior and inferior to cervical arthrodesis. Previous in vivo results have been conflicting, indicating that maximal ROM may or may not increase superior and/or inferior to the arthrodesis. There are no previous reports of midrange motion in arthrodesis patients and similar-aged controls. Methods Eight single-level (C5/C6) anterior arthrodesis patients (tested 7±1 months and 28±6 months post-surgery) and six asymptomatic control subjects (tested twice, 58±6 months apart) performed dynamic full ROM flexion/extension and axial rotation while biplane radiographs were collected at 30 images/s. A previously validated tracking process determined three-dimensional vertebral position from each pair of radiographs with sub-millimeter accuracy. The intervertebral maximal ROM and midrange motion in flexion/extension, rotation, lateral bending, and anterior-posterior translation were compared between test dates and between groups. Results Adjacent segment maximal ROM did not increase over time during flexion/extension or rotation movements. Adjacent segment maximal rotational ROM was not significantly greater in arthrodesis patients than in corresponding motion segments of similar-aged controls. C4/C5 adjacent segment rotation during the midrange of head motion and maximal anterior-posterior translation were significantly greater in arthrodesis patients than in the corresponding motion segment in controls on the second test date. Conclusions C5/C6 arthrodesis appears to significantly affect midrange, but not end-range, adjacent segment motions. The effects of arthrodesis on adjacent segment motion may be best evaluated by longitudinal studies that compare maximal and midrange adjacent segment motion to corresponding motion segments of similar-aged controls to determine if the adjacent segment motion is truly excessive. PMID:27831986

Longitudinal Study of the Six Degrees of Freedom Cervical Spine Range of Motion During Dynamic Flexion, Extension, and Rotation After Single-level Anterior Arthrodesis.

PubMed

Anderst, William J; West, Tyler; Donaldson, William F; Lee, Joon Y; Kang, James D

2016-11-15

A longitudinal study using biplane radiography to measure in vivo intervertebral range of motion (ROM) during dynamic flexion/extension, and rotation. To longitudinally compare intervertebral maximal ROM and midrange motion in asymptomatic control subjects and single-level arthrodesis patients. In vitro studies consistently report that adjacent segment maximal ROM increases superior and inferior to cervical arthrodesis. Previous in vivo results have been conflicting, indicating that maximal ROM may or may not increase superior and/or inferior to the arthrodesis. There are no previous reports of midrange motion in arthrodesis patients and similar-aged controls. Eight single-level (C5/C6) anterior arthrodesis patients (tested 7 ± 1 months and 28 ± 6 months postsurgery) and six asymptomatic control subjects (tested twice, 58 ± 6 months apart) performed dynamic full ROM flexion/extension and axial rotation whereas biplane radiographs were collected at 30 images per second. A previously validated tracking process determined three-dimensional vertebral position from each pair of radiographs with submillimeter accuracy. The intervertebral maximal ROM and midrange motion in flexion/extension, rotation, lateral bending, and anterior-posterior translation were compared between test dates and between groups. Adjacent segment maximal ROM did not increase over time during flexion/extension, or rotation movements. Adjacent segment maximal rotational ROM was not significantly greater in arthrodesis patients than in corresponding motion segments of similar-aged controls. C4/C5 adjacent segment rotation during the midrange of head motion and maximal anterior-posterior translation were significantly greater in arthrodesis patients than in the corresponding motion segment in controls on the second test date. C5/C6 arthrodesis appears to significantly affect midrange, but not end-range, adjacent segment motions. The effects of arthrodesis on adjacent segment motion may be best evaluated by longitudinal studies that compare maximal and midrange adjacent segment motion to corresponding motion segments of similar-aged controls to determine if the adjacent segment motion is truly excessive. 3.

Function and structure of the deep cervical extensor muscles in patients with neck pain.

PubMed

Schomacher, Jochen; Falla, Deborah

2013-10-01

The deep cervical extensors are anatomically able to control segmental movements of the cervical spine in concert with the deep cervical flexors. Several investigations have confirmed changes in cervical flexor muscle control in patients with neck pain and as a result, effective evidence-based therapeutic exercises have been developed to address such dysfunctions. However, knowledge on how the deep extensor muscles behave in patients with neck pain disorders is scare. Structural changes such as higher concentration of fat within the muscle, variable cross-sectional area and higher proportions of type II fibres have been observed in the deep cervical extensors of patients with neck pain compared to healthy controls. These findings suggest that the behaviour of the deep extensors may be altered in patients with neck pain. Consistent with this hypothesis, a recent series of studies confirm that patients display reduced activation of the deep cervical extensors as well as less defined activation patterns. This article provides an overview of the various different structural and functional changes in the deep neck extensor muscles documented in patients with neck pain. Relevant recommendations for the management of muscle dysfunction in patients with neck pain are presented. Copyright © 2013 Elsevier Ltd. All rights reserved.

Addition of instrumented fusion after posterior decompression surgery suppresses thickening of ossification of the posterior longitudinal ligament of the cervical spine.

PubMed

Ota, Mitsutoshi; Furuya, Takeo; Maki, Satoshi; Inada, Taigo; Kamiya, Koshiro; Ijima, Yasushi; Saito, Junya; Takahashi, Kazuhisa; Yamazaki, Masashi; Aramomi, Masaaki; Mannoji, Chikato; Koda, Masao

2016-12-01

Laminoplasty (LMP) is a widely accepted surgical procedure for ossification of the posterior longitudinal ligament (OPLL) of the cervical spine. Progression of OPLL can occur in the long term after LMP. The aim of the present study was to determine whether addition of the instrumented fusion, (posterior decompression with instrumented fusion [PDF]), can suppress progression of OPLL or not. The present study included 50 patients who underwent LMP (n=23) or PDF (n=27) for OPLL of the cervical spine. We performed open door laminoplasty. PDF surgery was performed by double-door laminoplasty followed by instrumented fusion. We observed the non-ossified segment of the OPLL and measured the thickness of the OPLL at the thickest segment with pre- and postoperative sagittal CT multi-planar reconstruction images. Postoperative CT scan revealed fusion of the non-ossified segment of the OPLL was obtained in 4/23 patients (17%) in the LPM group and in 23/27 patients (85%) in the PDF group, showing a significant difference between both groups (p=0.003). Progression of the thickness of the OPLL in the PDF group (-0.1±0.4mm) was significantly smaller than in the LMP group (0.6±0.7mm, p=0.0002). The proportion of patients showing the decrease in thickness of OPLL was significantly larger in the PDF group (6/27 patients; 22%) than in the LMP group (0/23 patients; 0%, p=0.05). In conclusion, PDF surgery can suppress the thickening of OPLL. Copyright © 2016 Elsevier Ltd. All rights reserved.

Propagation of registration uncertainty during multi-fraction cervical cancer brachytherapy

NASA Astrophysics Data System (ADS)

Amir-Khalili, A.; Hamarneh, G.; Zakariaee, R.; Spadinger, I.; Abugharbieh, R.

2017-10-01

Multi-fraction cervical cancer brachytherapy is a form of image-guided radiotherapy that heavily relies on 3D imaging during treatment planning, delivery, and quality control. In this context, deformable image registration can increase the accuracy of dosimetric evaluations, provided that one can account for the uncertainties associated with the registration process. To enable such capability, we propose a mathematical framework that first estimates the registration uncertainty and subsequently propagates the effects of the computed uncertainties from the registration stage through to the visualizations, organ segmentations, and dosimetric evaluations. To ensure the practicality of our proposed framework in real world image-guided radiotherapy contexts, we implemented our technique via a computationally efficient and generalizable algorithm that is compatible with existing deformable image registration software. In our clinical context of fractionated cervical cancer brachytherapy, we perform a retrospective analysis on 37 patients and present evidence that our proposed methodology for computing and propagating registration uncertainties may be beneficial during therapy planning and quality control. Specifically, we quantify and visualize the influence of registration uncertainty on dosimetric analysis during the computation of the total accumulated radiation dose on the bladder wall. We further show how registration uncertainty may be leveraged into enhanced visualizations that depict the quality of the registration and highlight potential deviations from the treatment plan prior to the delivery of radiation treatment. Finally, we show that we can improve the transfer of delineated volumetric organ segmentation labels from one fraction to the next by encoding the computed registration uncertainties into the segmentation labels.

Pilot Study of an Open-source Image Analysis Software for Automated Screening of Conventional Cervical Smears.

PubMed

Sanyal, Parikshit; Ganguli, Prosenjit; Barui, Sanghita; Deb, Prabal

2018-01-01

The Pap stained cervical smear is a screening tool for cervical cancer. Commercial systems are used for automated screening of liquid based cervical smears. However, there is no image analysis software used for conventional cervical smears. The aim of this study was to develop and test the diagnostic accuracy of a software for analysis of conventional smears. The software was developed using Python programming language and open source libraries. It was standardized with images from Bethesda Interobserver Reproducibility Project. One hundred and thirty images from smears which were reported Negative for Intraepithelial Lesion or Malignancy (NILM), and 45 images where some abnormality has been reported, were collected from the archives of the hospital. The software was then tested on the images. The software was able to segregate images based on overall nuclear: cytoplasmic ratio, coefficient of variation (CV) in nuclear size, nuclear membrane irregularity, and clustering. 68.88% of abnormal images were flagged by the software, as well as 19.23% of NILM images. The major difficulties faced were segmentation of overlapping cell clusters and separation of neutrophils. The software shows potential as a screening tool for conventional cervical smears; however, further refinement in technique is required.

Understanding cervical cancer prevention and screening in Chuukese women in Hawaii.

PubMed

Wong, Vanessa S; Kawamoto, Crissy T

2010-06-01

Cervical cancer is the primary cause of death due to cancer in women in Chuuk State, Federated States of Micronesia. The Chuukese population is the fastest growing segment of the Micronesian community in Hawaii. Little is known about the health beliefs or practices of this population in Hawaii. The purpose of this project was to describe the knowledge, attitudes, and beliefs of Chuukese women in Hawaii regarding cervical cancer prevention and screening. Research assistants from the Chuukese community were recruited and trained as members of the research team. A culturally sensitive survey tool was developed and piloted by the research team and used to interview ten key informants from the Chuukese community in Honolulu, Hawaii. There is limited knowledge about cervical cancer, especially the association with human papillomavirus (HPV). This may be indicative of a lack of health information in general. Fear, privacy concerns, lack of awareness and cultural beliefs represent the main barriers mentioned when discussing cervical cancer. Education, done in a group setting with other women, is the most recommended method of informing this community and improving preventive and screening services for cervical cancer in these women. Hawaii Medical Journal Copyright 2010.

Two-level noncontiguous versus three-level anterior cervical discectomy and fusion: a biomechanical comparison.

PubMed

Finn, Michael A; Samuelson, Mical M; Bishop, Frank; Bachus, Kent N; Brodke, Darrel S

2011-03-15

Biomechanical study. To determine biomechanical forces exerted on intermediate and adjacent segments after two- or three-level fusion for treatment of noncontiguous levels. Increased motion adjacent to fused spinal segments is postulated to be a driving force in adjacent segment degeneration. Occasionally, a patient requires treatment of noncontiguous levels on either side of a normal level. The biomechanical forces exerted on the intermediate and adjacent levels are unknown. Seven intact human cadaveric cervical spines (C3-T1) were mounted in a custom seven-axis spine simulator equipped with a follower load apparatus and OptoTRAK three-dimensional tracking system. Each intact specimen underwent five cycles each of flexion/extension, lateral bending, and axial rotation under a ± 1.5 Nm moment and a 100-Nm axial follower load. Applied torque and motion data in each axis of motion and level were recorded. Testing was repeated under the same parameters after C4-C5 and C6-C7 diskectomies were performed and fused with rigid cervical plates and interbody spacers and again after a three-level fusion from C4 to C7. Range of motion was modestly increased (35%) in the intermediate and adjacent levels in the skip fusion construct. A significant or nearly significant difference was reached in seven of nine moments. With the three-level fusion construct, motion at the infra- and supra-adjacent levels was significantly or nearly significantly increased in all applied moments over the intact and the two-level noncontiguous construct. The magnitude of this change was substantial (72%). Infra- and supra-adjacent levels experienced a marked increase in strain in all moments with a three-level fusion, whereas the intermediate, supra-, and infra-adjacent segments of a two-level fusion experienced modest strain moments relative to intact. It would be appropriate to consider noncontiguous fusions instead of a three-level fusion when confronted with nonadjacent disease.

[A clinical study on different decompression methods in cervical spondylosis].

PubMed

Ma, Xun; Zhao, Xiao-fei; Zhao, Yi-bo

2009-04-15

To analyze the different decompression methods to treat cervical spondylosis based on imageological evaluation. Two hundred and sixty three consecutive patients with cervical spondylosis between Nov. 2004 and Oct. 2007 were involved in this study. Patients were distributed to different operation groups based on the preoperative imageological evaluation, including anterior or posterior decompression methods. The Anterior method is to use the discectomy of one to three segments, autogenous iliac graft or titanium mesh or cage fusion and titanium plate fixation, or subtotal vertebrectomy of one to two segments autogenous iliac graft or titanium mesh fusion and titanium plate fixation, or discectomy plus subtotal vertebrectomy, The posterior expansive single open door laminoplasty and other operation types. All the patients were divided into different groups by the preoperative imageological evaluation, age, sex and course of diseases. Then we collected each group's preoperative and postoperative JOA scores and mean improvement rate to evaluate the postoperative effect by different decompression methods. Two hundred and thirty five patients were followed up with a mean period of 18 months (range, 4 to 36 months). JOA scores of all patients were improved by different degrees after operations. Anterior and posterior decompression methods both can achieve higher mean improvement rates. There were no significant differences in mean improvement rates between anterior groups, and so did male and female (P > 0.05). The effect will decrease as age increases or the course of disease prolongs. Statistical significance existed among the different age groups and between course groups (P < 0.05). Anterior and posterior decompression methods both can achieve good effect. The key point is to choose the surgical indication correctly, decompress thoroughly, and make the fusion reliable and fixation firm. In regard to the patients' imageological evaluation, the methods should be differentiated. The anterior operation type included discectomy of one to three segments, subtotal vertebrectomy of one to two segments and discectomy plus subtotal vertebra ectomy.

Factors predicting dysphagia after anterior cervical surgery

PubMed Central

Wang, Tao; Ma, Lei; Yang, Da-Long; Wang, Hui; Bai, Zhi-Long; Zhang, Li-Jun; Ding, Wen-Yuan

2017-01-01

Abstract A multicenter retrospective study. The purpose of this study was to explore risk factors of dysphagia after anterior cervical surgery and factors affecting rehabilitation of dysphagia 2 years after surgery. Patients who underwent anterior cervical surgery at 3 centers from January 2010 to January 2013 were included. The possible factors included 3 aspects: demographic variables—age, sex, body mass index (BMI): hypertension, diabetes, heart disease, smoking, alcohol use, diagnose (cervical spondylotic myelopathy or ossification of posterior longitudinal ligament), preoperative visual analogue scale (VAS), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA), surgical-related variables—surgical option (ACDF, ACCF, ACCDF, or Zero profile), operation time, blood loss, operative level, superior fusion segment, incision length, angle of C2 to C7, height of C2 to C7, cervical circumference, cervical circumference/height of C2 to C7. The results of our study indicated that the rate of dysphagia at 0, 3, 6, 12, and 24 months after surgery was 20%, 5.4%, 2.4%, 1.1%, and 0.4%, respectively. Our results showed that age (58.8 years old), BMI (27.3 kg/m2), course of disease (11.6 months), operation time (103.2 min), blood loss (151.6 mL), incision length (9.1 cm), cervical circumference (46.8 cm), angle of C2 to C7 (15.3°), cervical circumference/height of C2 to C7 (4.8), preoperative VAS (7.5), and ODI (0.6) in dysphagia group were significantly higher than those (52.0, 24.6, 8.6, 88.2, 121.6, 8.6, 42.3, 12.6, 3.7, 5.6, and 0.4, respectively) in nondysphagia group; however, height of C2 to C7 (9.9 vs 11.7 cm) and preoperative JOA (8.3 vs 10.7) had opposite trend between 2 groups. We could also infer that female, smoking, diabetes, ossification of posterior longitudinal ligament, ACCDF, multilevel surgery, and superior fusion segment including C2 to C3 or C6 to C7 were the risk factors for dysphagia after surgery immediately. However, till 2 years after surgery, only 2 risk factors, smoking and diabetes, could slow rehabilitation of dysphagia. Many factors could significantly increase rate of dysphagia after anterior cervical surgery. Operation time as a vital factor markedly increases immediate postoperative dysphagia and smoking, as the most important factor, lower recovery of dysphagia. Further study is needed to prove if these factors could influence dysphagia. PMID:28834916

Biomechanical effects of fusion levels on the risk of proximal junctional failure and kyphosis in lumbar spinal fusion surgery.

PubMed

Park, Won Man; Choi, Dae Kyung; Kim, Kyungsoo; Kim, Yongjung J; Kim, Yoon Hyuk

2015-12-01

Spinal fusion surgery is a widely used surgical procedure for sagittal realignment. Clinical studies have reported that spinal fusion may cause proximal junctional kyphosis and failure with disc failure, vertebral fracture, and/or failure at the implant-bone interface. However, the biomechanical injury mechanisms of proximal junctional kyphosis and failure remain unclear. A finite element model of the thoracolumbar spine was used. Nine fusion models with pedicle screw systems implanted at the L2-L3, L3-L4, L4-L5, L5-S1, L2-L4, L3-L5, L4-S1, L2-L5, and L3-S1 levels were developed based on the respective surgical protocols. The developed models simulated flexion-extension using hybrid testing protocol. When spinal fusion was performed at more distal levels, particularly at the L5-S1 level, the following biomechanical properties increased during flexion-extension: range of motion, stress on the annulus fibrosus fibers and vertebra at the adjacent motion segment, and the magnitude of axial forces on the pedicle screw at the uppermost instrumented vertebra. The results of this study demonstrate that more distal fusion levels, particularly in spinal fusion including the L5-S1 level, lead to greater increases in the risk of proximal junctional kyphosis and failure, as evidenced by larger ranges of motion, higher stresses on fibers of the annulus fibrosus and vertebra at the adjacent segment, and higher axial forces on the screw at the uppermost instrumented vertebra in flexion-extension. Therefore, fusion levels should be carefully selected to avoid proximal junctional kyphosis and failure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sentinel lymph node mapping in minimally invasive surgery: Role of imaging with color-segmented fluorescence (CSF).

PubMed

Lopez Labrousse, Maite I; Frumovitz, Michael; Guadalupe Patrono, M; Ramirez, Pedro T

2017-09-01

Sentinel lymph node mapping, alone or in combination with pelvic lymphadenectomy, is considered a standard approach in staging of patients with cervical or endometrial cancer [1-3]. The goal of this video is to demonstrate the use of indocyanine green (ICG) and color-segmented fluorescence when performing lymphatic mapping in patients with gynecologic malignancies. Injection of ICG is performed in two cervical sites using 1mL (0.5mL superficial and deep, respectively) at the 3 and 9 o'clock position. Sentinel lymph nodes are identified intraoperatively using the Pinpoint near-infrared imaging system (Novadaq, Ontario, CA). Color-segmented fluorescence is used to image different levels of ICG uptake demonstrating higher levels of perfusion. A color key on the side of the monitor shows the colors that coordinate with different levels of ICG uptake. Color-segmented fluorescence may help surgeons identify true sentinel nodes from fatty tissue that, although absorbing fluorescent dye, does not contain true nodal tissue. It is not intended to differentiate the primary sentinel node from secondary sentinel nodes. The key ranges from low levels of ICG uptake (gray) to the highest rate of ICG uptake (red). Bilateral sentinel lymph nodes are identified along the external iliac vessels using both standard and color-segmented fluorescence. No evidence of disease was noted after ultra-staging was performed in each of the sentinel nodes. Use of ICG in sentinel lymph node mapping allows for high bilateral detection rates. Color-segmented fluorescence may increase accuracy of sentinel lymph node identification over standard fluorescent imaging. The following are the supplementary data related to this article. Copyright © 2017 Elsevier Inc. All rights reserved.

Posterior Cervical Transfacet Fusion with Facetal Spacer for the Treatment of Single-Level Cervical Radiculopathy: A Randomized, Controlled Prospective Study.

PubMed

Lenzi, Jacopo; Nardone, Antonio; Passacantilli, Emiliano; Caporlingua, Alessandro; Lapadula, Gennaro; Caporlingua, Federico

2017-04-01

Single-level cervical radiculopathy may be treated conservatively with cervical tractions. Posterior cervical transfacet fusion with a facetal spacer is a viable option. The aim of the present study is to compare posterior cervical transfacet fusion with conservative physical treatment in single-level cervical radiculopathy. A total of 80 patients were randomized in 2 groups, a surgical group in which patients were given posterior cervical transfacet fusion and a traction group in which patients were treated conservatively with mechanical cervical tractions. Visual analog scale for arm and neck, Neck Disability Index, and Short Form-36 (SF-36) questionnaires were administered preoperatively and after treatment up to 12 months. After treatment, visual analog scale arm scores were greater in traction group (4.7 vs. 1.5 the day after treatment) and at follow-up controls (traction group vs. surgical group: 5.3 vs. 0.6 at 1 month, 3.6 vs. 0.3 at 6 months, 1.8 vs. 0.2 at 12 months). Neck Disability Index scores were lower in the surgical group (surgical group vs. traction group: 4.4 vs. 20.3 at 1 month, 1.3 vs. 10.5 at 6 months). SF-36 scores were greater in the surgical group (surgical group vs. traction group: 96 vs. 70 at 1 month, 96.5 vs. 82.6 at 6 months). Neck disability index and SF-36 scores were superimposable between the groups at 12-month follow-up. No adjacent-segment arthrosis or late complications were reported at 1-year follow-up in the surgical group. posterior cervical transfacet fusion is a safe and effective procedure to treat single-level cervical radiculopathy. Copyright © 2017 Elsevier Inc. All rights reserved.

Design of a mechanism to simulate the quasi-static moment-deflection behaviour of the osteoligamentous structure of the C3-C4 cervical spine segment in the flexion-extension and lateral bending directions.

PubMed

Chen, Samuel; Arsenault, Marc; Moglo, Kodjo

2012-11-01

The human neck is susceptible to traumatic injuries due to impacts as well as chronic injuries caused by loads such as those attributed to the wearing of heavy headgear. To facilitate the analysis of the loads that cause injuries to the cervical spine, it is possible to replicate the human neck's behaviour with mechanical devices. The goal of this work is to lay the foundation for the eventual development of a novel mechanism used to simulate the behaviour of the cervical spine during laboratory experiments. The research presented herein focuses on the design of a mechanism capable of reproducing the non-linear relationships between moments applied to the C3 vertebra and its corresponding rotations with respect to the C4 vertebra. The geometrical and mechanical properties of the mechanism are optimized based on the ability of the latter to replicate the load-deflection profile of the osteoligamentous structure of the C3-C4 vertebral pair in the flexion-extension and lateral bending directions. The results show that the proposed design concept is capable of faithfully replicating the non-linear behaviour of the motion segment within acceptable tolerances.

Sensory Alterations in Patients with Isolated Idiopathic Dystonia: An Exploratory Quantitative Sensory Testing Analysis.

PubMed

Paracka, Lejla; Wegner, Florian; Blahak, Christian; Abdallat, Mahmoud; Saryyeva, Assel; Dressler, Dirk; Karst, Matthias; Krauss, Joachim K

2017-01-01

Abnormalities in the somatosensory system are increasingly being recognized in patients with dystonia. The aim of this study was to investigate whether sensory abnormalities are confined to the dystonic body segments or whether there is a wider involvement in patients with idiopathic dystonia. For this purpose, we recruited 20 patients, 8 had generalized, 5 had segmental dystonia with upper extremity involvement, and 7 had cervical dystonia. In total, there were 13 patients with upper extremity involvement. We used Quantitative Sensory Testing (QST) at the back of the hand in all patients and at the shoulder in patients with cervical dystonia. The main finding on the hand QST was impaired cold detection threshold (CDT), dynamic mechanical allodynia (DMA), and thermal sensory limen (TSL). The alterations were present on both hands, but more pronounced on the side more affected with dystonia. Patients with cervical dystonia showed a reduced CDT and hot detection threshold (HDT), enhanced TSL and DMA at the back of the hand, whereas the shoulder QST only revealed increased cold pain threshold and DMA. In summary, QST clearly shows distinct sensory abnormalities in patients with idiopathic dystonia, which may also manifest in body regions without evident dystonia. Further studies with larger groups of dystonia patients are needed to prove the consistency of these findings.

Biomechanical Stability of a Stand-Alone Interbody Spacer in Two-Level and Hybrid Cervical Fusion Constructs

PubMed Central

Wagner, Scott C.; Tracey, Robert W.; Cody, John P.; Gaume, Rachel E.; Lehman, Ronald A.

2017-01-01

Study Design: In vitro human cadaveric biomechanical analysis. Objective: To evaluate the segmental stability of a stand-alone spacer (SAS) device compared with the traditional anterior cervical plate (ACP) construct in the setting of a 2-level cervical fusion construct or as a hybrid construct adjacent to a previous 1-level ACP construct. Methods: Twelve human cadaveric cervical spines (C2-T1) were nondestructively tested with a custom 6-degree-of-freedom spine simulator under axial rotation (AR), flexion-extension (FE), and lateral bending (LB) at 1.5 N m loads. After intact analysis, each specimen underwent instrumentation and testing in the following 3 configurations, with each specimen randomized to the order of construct: (A) C5-7 SAS; (B) C5-6 ACP, and C6-7 SAS (hybrid); (C) C5-7 ACP. Full range of motion (ROM) data at C5-C7 was obtained and analyzed by each loading modality utilizing mean comparisons with repeated measures analysis of variance with Sidak correction for multiple comparisons. Results: Compared with the intact specimen, all tested constructs had significantly increased segmental stability at C5-C7 in AR and FE ROM, with no difference in LB ROM. At C5-C6, all test constructs again had increased segmental stability in FE ROM compared with intact (10.9° ± 4.4° Intact vs SAS 6.6° ± 3.2°, P < .001; vs.Hybrid 2.9° ± 2.0°, P = .005; vs ACP 2.1° ± 1.4°, P < .001), but had no difference in AR and LB ROM. Analysis of C6-C7 ROM demonstrated all test groups had significantly greater segmental stability in FE ROM compared with intact (9.6° ± 2.7° Intact vs SAS 5.0° ± 3.0°, P = .018; vs Hybrid 5.0° ± 2.7°, P = .018; vs ACP 4.4° ± 5.2°, P = .005). Only the hybrid and 2-level ACP constructs had increased stability at C6-C7 in AR ROM compared with intact, with no difference for all test groups in LB ROM. Comparison between test constructs demonstrated no difference in C5-C7 and C6-C7 segmental stability in all planes of motion. However, at C5-C6 comparison between test constructs found the 2-level SAS had significantly less segmental stability compared to the hybrid (6.6° ± 3.2° vs 2.9° ± 2.0°, P = .025) and ACP (6.6° ± 3.2° vs 2.1° ± 1.4°, P = .004). Conclusions: Our study found the currently tested SAS device may be a reasonable option as part of a 2-level hybrid construct, when used below an adjacent 1-level ACP, but should be used with careful consideration as a 2-level SAS construct. Consequences of decreased segmental stability in FE are unknown; however, optimal immediate fixation stability is an important surgical principle to avoid loss of fixation, segmental kyphosis, interbody graft subsidence, and pseudarthrosis. PMID:28989848

[Clinical outcomes of cervical disc herniation treated by posterior percutaneous endoscopic cervical discectomy].

PubMed

Chen, B L; Li, Y J; Lin, Y P; Du, Y X; Zhao, S; Su, G Y

2017-12-01

Objective: To evaluate the clinical outcomes of posterior percutaneous endoscopic cervical discectomy (PPECD) for cervical disc herniation. Methods: A total of 23 patients who underwent PPECD for cervical disc herniation at Department of Spine Surgery, Guangdong Provincial Hospital of Chinese Medicine from August 2014 to April 2016 were reviewed. The mean age of the 17 males and 6 females was 49.5 years (range from 31 to 61 years). All patients had unilateral upper limb radiating symptoms, 13 patients with right upper limb radiating pain and 10 patients with left upper limb radiation pain, 17 patients with neck pain symptoms. Responsible segment: left C(4-5) 1 case, right C(4-5) 2 cases, left C(5-6) 4 cases, right C(5-6) 8 cases, left C(6-7) 5 cases, right C(6-7) 3 example.Operating time, length of hospitalization, complications, neck and arm Visual analog scale(VAS), and Neck Disability Index(NDI) were evaluated. The excellent and good rate of surgery was evaluated by using the Odom criteria. Harrison method was used to measure cervical curvature. The Cobb angle of the surgical segment was measured on the X-ray, and the range of motion (ROM) was calculated. The changes of the cervical curvature and the surgical segment ROM were compared pre- and post-operation. Results: The operation time was 94.1 min (range from 80 to 150 min). The average length of hospital stay was 4.8 days. The mean follow-up period was 23.5 months (range from 15 to 35 months). The preoperative arm VAS score was 6.95±0.88, 1-week postoperative arm VAS score was 2.09±0.67, the last follow-up arm VAS score was 1.04±0.98. The preoperative neck VAS score was 3.04±0.77, 1-week postoperative neck VAS score was 1.52±0.51 and the last follow-up neck VAS score was 0.61±0.78. The 1-week postoperative and last follow-up arm and neck VAS scores were significantly reduced compared with pre-operation ( P <0.01). Compared with 1 week after surgery, the last follow-up of the arm and neck VAS score further reduced, the difference was statistically significant ( P <0.01). The preoperative NDI was (58.52±4.98)%, the 1-week postoperative NDI was (33.74±4.72)%, the last follow-up NDI was (19.22±3.23)%. The 1-week postoperative and last follow-up NDI was significantly improved compared with pre-operation ( P <0.01). Compared with 1 week after surgery, the last follow-up of the NDI further improved, the difference was statistically significant ( P <0.01). The 1-week postoperative cervical curvature was (14.65±2.89)°, and it was improved compared with preoperative(14.23±3.06)°, the difference was statistically significant ( P <0.05) . The last follow-up was cervical curvature(14.64±2.68)°, there was no significant difference compared with preoperative ( P > 0.05). The preoperative surgical ROM was(5.37±1.83)°, 1-week postoperative was(5.53±1.52)°, and the last follow-up was (5.62±1.48)°, there was no significant difference pre-operative and post-operation ( P > 0.05). The excellent and good rate was 91.3% (excellent in 16 cases, good in 5 cases, 2 cases). There was no nerve root injury, cerebrospinal fluid leakage, wound infection, and other complications. Conclusions: PPECD is a sufficient and safe supplement for cervical disc herniation, its recent clinical efficacy was good. And it has no significant effect on cervical stability.

Magnetic resonance diffusion tensor imaging of cervical spinal cord and lumbosacral enlargement in patients with cervical spondylotic myelopathy.

PubMed

Chen, Xueming; Kong, Chao; Feng, Shiqing; Guan, Hua; Yu, Zhenshan; Cui, Libin; Wang, Yanhui

2016-06-01

To identify the correlations of diffusion tensor imaging (DTI) indices between the cervical spinal cord and lumbosacral enlargement in healthy volunteers and patients with cervical spondylotic myelopathy (CSM). DTI was performed at the cervical spinal cord and lumbosacral enlargement in 10 CSM patients and 10 volunteers at 1.5T. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values of were measured and compared between CSM patients and volunteers. DTI indices of different cervical segments in volunteers were compared. DTI indices of the cervical spinal cord were correlated with those of the lumbosacral enlargement. In healthy subjects, DTI indices of different cervical cord sections showed no significant difference (ADC: F = 0.62; P = 0.65; FA: F = 1.228; P = 0.312); there was no correlation between the DTI indices of the cervical spinal cord and those of the lumbosacral enlargement (ADC: r = 0.442, P = 0.201; FA: r = -0.054, P = 0.881). In the CSM patients, the ADC value significantly increased, while the FA value significantly decreased in the cervical spinal cord (ADC: P = 0.002; FA: P < 0.001) and lumbosacral enlargement (ADC: P = 0.003; FA: P < 0.001) compared with the healthy group. Both DTI indices showed no correlation between the cervical spinal cord and those of the lumbosacral enlargement in the CSM group (ADC: r = -0.052, P = 0.887; FA: r = 0.129, P = 0.722). The ADC value of the cervical spinal cord and lumbosacral enlargement in CSM patients showed significant increase compared with healthy volunteers, while the FA value significantly decreased. Both DTI indices of the cervical spinal cord had no linear correlation with those of the lumbosacral enlargement. J. Magn. Reson. Imaging 2016;43:1484-1491. © 2015 Wiley Periodicals, Inc.

Choice of surgical approach for ossification of the posterior longitudinal ligament in combination with cervical disc hernia.

PubMed

Yang, Hai-song; Chen, De-yu; Lu, Xu-hua; Yang, Li-li; Yan, Wang-jun; Yuan, Wen; Chen, Yu

2010-03-01

Ossification of the posterior longitudinal ligament (OPLL) is a common spinal disorder that presents with or without cervical myelopathy. Furthermore, there is evidence suggesting that OPLL often coexists with cervical disc hernia (CDH), and that the latter is the more important compression factor. To raise the awareness of CDH in OPLL for spinal surgeons, we performed a retrospective study on 142 patients with radiologically proven OPLL who had received surgery between January 2004 and January 2008 in our hospital. Plain radiograph, three-dimensional computed tomography construction (3D CT), and magnetic resonance imaging (MRI) of the cervical spine were all performed. Twenty-six patients with obvious CDH (15 of segmental-type, nine of mixed-type, two of continuous-type) were selected via clinical and radiographic features, and intraoperative findings. By MRI, the most commonly involved level was C5/6, followed by C3/4, C4/5, and C6/7. The areas of greatest spinal cord compression were at the disc levels because of herniated cervical discs. Eight patients were decompressed via anterior cervical discectomy and fusion (ACDF), 13 patients via anterior cervical corpectomy and fusion (ACCF), and five patients via ACDF combined with posterior laminectomy and fusion. The outcomes were all favorable. In conclusion, surgeons should consider the potential for CDH when performing spinal cord decompression and deciding the surgical approach in patients presenting with OPLL.

Upper-mantle seismic structure in a region of incipient continental breakup: northern Ethiopian rift

NASA Astrophysics Data System (ADS)

Bastow, Ian D.; Stuart, Graham W.; Kendall, J.-Michael; Ebinger, Cynthia J.

2005-08-01

The northern Ethiopian rift forms the third arm of the Red Sea, Gulf of Aden triple junction, and marks the transition from continental rifting in the East African rift to incipient oceanic spreading in Afar. We determine the P- and S-wave velocity structure beneath the northern Ethiopian rift using independent tomographic inversion of P- and S-wave relative arrival-time residuals from teleseismic earthquakes recorded by the Ethiopia Afar Geoscientific Lithospheric Experiment (EAGLE) passive experiment using the regularised non-linear least-squares inversion method of VanDecar. Our 79 broad-band instruments covered an area 250 × 350 km centred on the Boset magmatic segment ~70 km SE of Addis Ababa in the centre of the northern Ethiopian rift. The study area encompasses several rift segments showing increasing degrees of extension and magmatic intrusion moving from south to north into the Afar depression. Analysis of relative arrival-time residuals shows that the rift flanks are asymmetric with arrivals associated with the southeastern Somalian Plate faster (~0.65 s for the P waves; ~2 s for the S waves) than the northwestern Nubian Plate. Our tomographic inversions image a 75 km wide tabular low-velocity zone (δVP~-1.5 per cent, δVS~-4 per cent) beneath the less-evolved southern part of the rift in the uppermost 200-250 km of the mantle. At depths of >100 km, north of 8.5°N, this low-velocity anomaly broadens laterally and appears to be connected to deeper low-velocity structures under the Afar depression. An off-rift low-velocity structure extending perpendicular to the rift axis correlates with the eastern limit of the E-W trending reactivated Precambrian Ambo-Guder fault zone that is delineated by Quaternary eruptive centres. Along axis, the low-velocity upwelling beneath the rift is segmented, with low-velocity material in the uppermost 100 km often offset to the side of the rift with the highest rift flank topography. Our observations from this magmatic rift zone, which is transitional between continental and oceanic rifting, do not support detachment fault models of lithospheric extension but instead point to strain accommodation via magma assisted rifting.

Split thickness skin graft for cervicovaginal reconstruction in congenital atresia of cervix.

PubMed

Zhang, Xuyin; Han, Tiantian; Ding, Jingxin; Hua, Keqin

2015-10-01

To introduce a new technique that combines laparoscopic and vaginal cervicovaginal reconstruction using split thickness skin graft in patients with congenital atresia of the cervix. Video article introducing a new surgical technique. University hospital. A 16-year-old patient with congenital cervical atresia, vaginal dysgenesis, and ovarian endometrial cyst. An original technique of combined laparoscopic and vaginal cervicovaginal reconstruction using split thickness skin graft for cervicovaginal reconstruction. A midline incision at the vaginal introitus was made, and a 9-cm canal was made between the bladder and the rectum using sharp and blunt dissection along the anatomic vaginal route, with the aid of laparoscopy to ensure correct orientation. A 14 × 12 cm split thickness skin graft was harvested from the right lateral thigh. By laparoscopy, the level of the lowest pole of the uterine cavity was exposed and the cervix was incised by shape dissection. The proximal segment of the harvested skin to the lower uterine segment was secured, and the distal segment was sutured with the upper margin of vulva vaginally. Surgical technique reports in anonymous patients are exempted from ethical approval by the Institutional Review Board. The patient gave consent to use the video in the article. The procedure was successfully completed. Since February 2013, our experiences of combined laparoscopic and vaginal cervicovaginal reconstruction using split thickness skin graft in 10 patients with congenital atresia of cervix were positive, with successful results and without complications or cervical, or vaginal stenosis. Our technique is feasible and safe for congenital atresia of cervix, with successful results and without complications or cervical or vaginal stenosis. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Degenerative changes in adolescent spines: a comparison of motocross racers and age-matched controls.

PubMed

Daniels, David J; Luo, T David; Puffer, Ross; McIntosh, Amy L; Larson, A Noelle; Wetjen, Nicholas M; Clarke, Michelle J

2015-03-01

Motocross racing is a popular sport; however, its impact on the growing/developing pediatric spine is unknown. Using a retrospective cohort model, the authors compared the degree of advanced degenerative findings in young motocross racers with findings in age-matched controls. Patients who had been treated for motocross-related injury at the authors' institution between 2000 and 2007 and had been under 18 years of age at the time of injury and had undergone plain radiographic or CT examination of any spinal region were eligible for inclusion. Imaging was reviewed in a blinded fashion by 3 physicians for degenerative findings, including endplate abnormalities, loss of vertebral body height, wedging, and malalignment. Acute pathological segments were excluded. Spine radiographs from age-matched controls were similarly reviewed and the findings were compared. The motocross cohort consisted of 29 riders (mean age 14.7 years; 82% male); the control cohort consisted of 45 adolescents (mean age 14.3 years; 71% male). In the cervical spine, the motocross cohort had 55 abnormalities in 203 segments (average 1.90 abnormalities/patient) compared with 20 abnormalities in 213 segments in the controls (average 0.65/patient) (p = 0.006, Student t-test). In the thoracic spine, the motocross riders had 51 abnormalities in 292 segments (average 2.04 abnormalities/patient) compared with 25 abnormalities in 299 segments in the controls (average 1.00/patient) (p = 0.045). In the lumbar spine, the motocross cohort had 11 abnormalities in 123 segments (average 0.44 abnormalities/patient) compared with 15 abnormalities in 150 segments in the controls (average 0.50/patient) (p = 0.197). Increased degenerative changes in the cervical and thoracic spine were identified in adolescent motocross racers compared with age-matched controls. The long-term consequences of these changes are unknown; however, athletes and parents should be counseled accordingly about participation in motocross activities.

Manual treatment effects to the upper cervical apophysial joints before, during, and after endotracheal anesthesia: a placebo-controlled comparison.

PubMed

Buchmann, Johannes; Wende, Klaus; Kundt, Guenther; Haessler, Frank

2005-04-01

In this preliminary, placebo-controlled clinical trial, two different manual treatments were compared, spinal manipulation and postisometric relaxation, for dysfunctional motion segments of the upper cervical spinal column. The influence of the muscular portion on the joint-play restriction of a motion segment can be ignored in anesthesia, and the manual evaluation of this joint-play restriction must be focused on nonmuscular structures. By retesting in anesthesia, it is possible to examine whether mobilization and manipulation affect exclusively the muscular structures or also affect the other parts of the motion segment. Conclusions can be drawn about the superiority of one or both treatments and about the structural basis of the restricted joint play and its palpation. A total of 26 inpatients at the surgical or orthopedic department of the University of Rostock were examined manually at four testing times: before and after manual treatment, in anesthesia, and within 24 hrs of completing anesthesia. They were randomized into three groups: postisometric relaxation (mobilization), spinal manipulation (thrust technique), and placebo. A highly significant effect for both treatments was found posttherapeutically (P < 0.01) but not for placebo. In anesthesia, the treatment effect of spinal manipulation was further significant (P < 0.01) when compared with placebo. For postisometric relaxation, however, it was not (P = 0.160). A significant difference between spinal manipulation and postisometric relaxation was not found in anesthesia (P = 0.137). The treatment effect postnarcotically was further significant when compared with placebo only for spinal manipulation (P = 0.011). Both treatments are superior to placebo. Postisometric relaxation seems to affect mainly the muscular parts of the treated segments and less so the other parts, such as the joint capsule or the segmental affiliated ligaments and fascia. Spinal manipulation seems to influence all other segmental parts more effectively, and the treatment effect persists longer. A joint-play restriction cannot be an exclusively muscular tension phenomenon. Segmental motion dysfunctions show a high variability in their spontaneous course.

Investigation of whiplash injuries in the upper cervical spine using a detailed neck model.

PubMed

Fice, Jason B; Cronin, Duane S

2012-04-05

Whiplash injuries continue to have significant societal cost; however, the mechanism and location of whiplash injury is still under investigation. Recently, the upper cervical spine ligaments, particularly the alar ligament, have been identified as a potential whiplash injury location. In this study, a detailed and validated explicit finite element model of a 50th percentile male cervical spine in a seated posture was used to investigate upper cervical spine response and the potential for whiplash injury resulting from vehicle crash scenarios. This model was previously validated at the segment and whole spine levels for both kinematics and soft tissue strains in frontal and rear impact scenarios. The model predicted increasing upper cervical spine ligament strain with increasing impact severity. Considering all upper cervical spine ligaments, the distractions in the apical and alar ligaments were the largest relative to their failure strains, in agreement with the clinical findings. The model predicted the potential for injury to the apical ligament for 15.2 g frontal or 11.7 g rear impacts, and to the alar ligament for a 20.7 g frontal or 14.4 g rear impact based on the ligament distractions. Future studies should consider the effect of initial occupant position on ligament distraction. Copyright © 2012 Elsevier Ltd. All rights reserved.

Surgical Therapy of Cervical Spine Fracture in Patients With Ankylosing Spondylitis

PubMed Central

Ma, Jun; Wang, Ce; Zhou, Xuhui; Zhou, Shengyuan; Jia, Lianshun

2015-01-01

Abstract The present study aimed to explore surgical treatments and assess the effects based on the features of cervical spine fracture in patients with ankylosing spondylitis (AS) and to summarize the experiences in perioperative management. Retrospective analysis was performed in 25 AS patients with cervical spine fracture treated in our hospital from January 2011 to December 2013. The patients were divided according to fracture segments, including 4 cases at C4 to C5, 8 cases at C5 to C6, and 13 cases at C6 to C7. Among them, 12 belonged to I type, 5 to II type, and 8 to III type based on the improved classification method for AS cervical spine fracture. The Subaxial Cervical Spine Injury Classification score for these patients was 7.2 ± 1.3, and the assessment of their neurological function states showed 6 patients (24%) were in American Spinal Injury Association (ASIA) A grade, 1 (4%) in ASIA B grade, 3 (12%) in ASIA C grade, 12 (48%) in ASIA D grade, and 3 (12%) in ASIA E grade. Surgical methods contained simple anterior approach alone, posterior approach alone, and combined posterior–anterior or anterior–posterior approach. The average duration of patients’ hospital stay was 38.6 ± 37.6, and the first surgical methods were as follows: anterior approach alone on 6 cases, posterior surgery alone on 9 cases, and combined posterior–anterior or anterior–posterior approach on 10 patients. The median segments of fixation and fusion were 4.1 ± 1.4 sections. Thirteen patients developed complications. During 2 to 36 months of postoperative follow-up, 1 patient died of respiratory failure caused by pulmonary infections 2 months after leaving hospital. At the end of the follow-up, bone graft fusion was achieved in the rest of patients, and obvious looseness or migration of internal fixation was not observed. In addition, the preoperative neurological injury in 12 patients (54.5%) was also alleviated in different levels. AS cervical spine fracture, an unstable fracture, should be treated with operation, and satisfactory effects will be achieved after the individualized surgical treatment according to the improved classification method for AS cervical spine fracture. PMID:26554765

Morphological properties of vestibulospinal neurons in primates

NASA Technical Reports Server (NTRS)

Boyle, Richard; Johanson, Curt

2003-01-01

The lateral and medial vestibulospinal tracts constitute the major descending pathways controlling extensor musculature of the body. We examined the axon morphology and synaptic input patterns and targets in the cervical spinal segments from these tract cells using intracellular recording and biocytin labeling in the squirrel monkey. Lumbosacral projecting cells represent a private, and mostly rapid, communication pathway between the dorsal Deiters' nucleus and the motor circuits controlling the lower limbs and tail. The cervical projecting cells provide both redundant and variable synaptic input to spinal cell groups, suggesting both general and specific control of the head and neck reflexes.

Distal Predominance of Electrodiagnostic Abnormalities in Early Stage Amyotrophic Lateral Sclerosis.

PubMed

Shayya, Luay; Babu, Suma; Pioro, Erik P; Li, Jianbo; Li, Yuebing

2018-05-09

We compare the electrodiagnostic (EDX) yield of limb muscles in revealing lower motor neuron (LMN) dysfunction by electromyography (EMG) in early stage amyotrophic lateral sclerosis (ALS). Single-site retrospective review Results: This study includes 122 consecutive patients with possible ALS as defined by revised El Escorial Criteria. Distal limb muscles show more frequent EMG abnormalities than proximal muscles. EDX yield is higher in the limb where weakness begins and when clinical signs of LMN dysfunction are evident. Adoption of Awaji criteria increases the yield of EMG positive segments significantly in the cervical (p<0.0005) and lumbosacral regions (P<0.0001), and upgrades 19 patients into probable and 1 patient into definite categories. Electromyographic abnormalities are distal limb-predominant in early stage ALS. A redefinition of an EDX-positive cervical or lumbosacral segment, with an emphasis on distal limb muscles, may result in an earlier ALS diagnosis. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

Zero-profile implant (Zero-p) versus plate cage benezech implant (PCB) in the treatment of single-level cervical spondylotic myelopathy.

PubMed

Wang, ZhiDong; Zhu, RuoFu; Yang, HuiLin; Shen, MinJie; Wang, Genlin; Chen, Kangwu; Gan, Minfeng; Li, Mao

2015-10-12

Anterior cervical discectomy and fusion is the golden standard for anterior surgery treating elderly cervical degenerative disease, but the previous implant has some problems such as looseness, translocation, sinking and dysphagia, So Zero-p implant and PCB implant have been developed to decrease the complications. The clinical data of 57 patients with single level cervical spondylotic myelopathy were retrospectively analyzed. 27 patients adopting Zero-p interbody fusion cage as implant (Zero-p group) and 30 patients adopting integrated plate cage benezech (PCB) as implant (PCB group) from January 2010 to October 2012. Observe whether are differences between the two groups of patients on operation time, intraoperatve blood loss,Japanese Orthopaedic Association (JOA) scores before and after operation, intervertebral height, cervical physiological curvature, fusion rate, Postoperative dysphagia rate and complications. Zero-p group's operation time is 98.2 + 15.2 min and its intraoperatve blood loss is 88.2 + 12.9 ml, both of which are lower than those of PCB group (109.8 + 16.9 min,95.2 + 11.6 ml ), so their differences are statistically significant (P < 0.05). The two groups' JOA scores 3 months after operation and in the last follow-up are significantly higher than those before operation, so the differences are statistically significant (P < 0.05). Coob angle 3 months after operation and in the last follow-up improves obviously compared with before operation, so the difference is statistically significant (P < 0.05). The two groups' operation segments intervertebral height 3 months after operation and in the last follow-up improves obviously compared with before operation, so the difference is statistically significant (P < 0.05) Zero-p group has one patient with dysphagia after operation and PCB group has four patients with dysphagia after operation, so there is no statistical differences between the two groups on dysphagia rate (P > 0.05, P = 0.415). PCB group has two patients with screws backing out and two patients with hoarseness after operation, the two groups' operation segments all saw bony union in the last follow-up. Zero-p group postoperative complications are lower than PCB group (P < 0.05, P = 0.044). Zero-profile implant and PCB implant both achieved good clinical effects on the treatment of cervical spondylotic myelopathy, the two groups both saw bony union in operation segments, but Zero-profile implant has the advantages of easy operation, short operation time, less intraoperatve blood loss and less complications.

Comparison of Outcomes in 3 Surgical Approaches for Dystrophic Cervical Kyphosis in Patients with Neurofibromatosis 1.

PubMed

Lin, Tao; Shao, Wei; Zhang, Ke; Gao, Rui; Zhou, Xuhui

2018-03-01

To compare outcomes of anterior-only (AO), posterior-only (PO), and anteroposterior (AP) surgical approaches for treatment of dystrophic cervical kyphosis in patients with neurofibromatosis 1 (NF1). This retrospective observational study included 81 patients with dystrophic cervical kyphosis secondary to NF1. Length of kyphosis, duration of halo traction, Cobb angle, C2-7-sagittal vertical axis (SVA), T1 slope, Neck Disability Index score, and postoperative complications were evaluated before and, if possible, after each surgical approach. AP approach provided the best outcomes (average spinal Cobb angle was corrected from 61.2 ± 9.1° to 5.7 ± 3.2°, P < 0.05); there was no significant difference between AO and PO approaches (P > 0.05). With regard to cervical sagittal balance, AP approach had the most improvements of C2-7-SVA (mean C2-7-SVA was corrected from 3.2 ± 9.2 mm to 12.8 ± 2.6 mm, P < 0.05); the difference between AO and PO approaches was not significant (P > 0.05). T1 slope results were similar to C2-7-SVA. Neck Disability Index score of all patients improved significantly after surgery (P < 0.05); specifically, patients who had an AP approach constituted the largest portion of the satisfied patient group. Postoperative junctional kyphosis occurred in 11 patients (1 AP approach, 6 AO approach, 4 PO approach); these findings correlated with patients with ≤5 fused segments. AP approach surgery provided the best correction of dystrophic cervical kyphosis and sagittal balance for patients with NF1. Patients undergoing an AP approach were more satisfied with their outcomes. Junctional kyphosis can be prevented effectively using an AP approach in patients with >5 fused segments. Copyright © 2017 Elsevier Inc. All rights reserved.

Strength of the cervical spine in compression and bending.

PubMed

Przybyla, Andrzej S; Skrzypiec, Daniel; Pollintine, Phillip; Dolan, Patricia; Adams, Michael A

2007-07-01

Cadaveric motion segment experiment. To compare the strength in bending and compression of the human cervical spine and to investigate which structures resist bending the most. The strength of the cervical spine when subjected to physiologically reasonable complex loading is unknown, as is the role of individual structures in resisting bending. A total of 22 human cervical motion segments, 64 to 89 years of age, were subjected to complex loading in bending and compression. Resistance to flexion and to extension was measured in consecutive tests. Sagittal-plane movements were recorded at 50 Hz using an optical two-dimensional "MacReflex" system. Experiments were repeated 1) after surgical removal of the spinous process, 2) after removal of both apophyseal joints, and 3) after the disc-vertebral body unit had been compressed to failure. Results were analyzed using t tests, analysis of variance, and linear regression. Results were compared with published data for the lumbar spine. The elastic limit in flexion was reached at 8.5 degrees (SD, 1.7 degrees ) with a bending moment of 6.7 Nm (SD, 1.7 Nm). In extension, values were 9.5 degrees (SD, 1.6 degrees ) and 8.4 Nm (3.5 Nm), respectively. Spinous processes (and associated ligaments) provided 48% (SD, 17%) of the resistance to flexion. Apophyseal joints provided 47% (SD, 16%) of the resistance to extension. In compression, the disc-vertebral body units reached the elastic limit at 1.23 kN (SD, 0.46 Nm) and their ultimate compressive strength was 2.40 kN (SD, 0.96 kN). Strength was greater in male specimens, depended on spinal level and tended to decrease with age. The cervical spine has approximately 20% of the bending strength of the lumbar spine but 45% of its compressive strength. This suggests that the neck is relatively vulnerable in bending.

Cervical spondylodiscitis with epidural abscess after knife stab wounds to the neck: A case report.

PubMed

Voelker, Anna; von der Hoeh, Nicolas H; Gulow, Jens; Heyde, Christoph-Eckhard

2015-08-01

Cervical spondylodiscitis is usually caused by pyogenic infections, associated with retropharyngeal abscesses, or due to the swallowing of foreign bodies. No cases of cervical spondylodiscitis caused by a penetrating neck injury have been published in the literature. We describe a case of cervical spondylodiscitis after multiple knife stab wounds to the lateral soft tissue of the neck. Case report and review of the literature. A 54-year-old patient was brought to our clinic with destructive spondylodiscitis C3/4 with paravertebral and epidural abscesses. He had been involved in a fight and had suffered multiple stab wounds to his neck with a knife 1 month prior. The initial CT scan had revealed one deeper wound canal behind the sternocleidomastoid muscle on the left side without any injury to the vessels. The wound was cleaned and an antibiotic therapy with cefuroxime was given for 1 week. After an uneventful and complete healing of the wound the patient developed severe neck pain. Inflammatory laboratory parameters were elevated, and a MRI of the neck revealed a distinct spondylodiscitis C3/4 with paravertebral and epidural abscess formations. Surgery was performed and included debridement, abscess drainage, decompression of the spinal canal, fusion of the C3/4 segment using an autologous iliac crest bone graft and a plate osteosynthesis. A course of calculated antibiotic therapy was administered for 8 weeks. Normal laboratory parameters and no radiological signs of an ongoing inflammatory process were observed during follow-up examinations. The C3/4 segment was consolidated. Stab wound injuries to the neck not only bear the risk of injuries to the nerves, vessels and organs of the neck but also increase the risk of developing secondary spondylodiscitis. Specifically, cervical spondylodiscitis can result in distinct neurological symptoms, and surgical intervention should be performed in a timely manner. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison of Zero-profile Device Versus Plate-and-Cage Implant in the Treatment of Symptomatic Adjacent Segment Disease after Anterior Cervical Discectomy and Fusion: A Minimum 2-Year Follow-Up Study.

PubMed

Shen, Yong; Du, Wei; Wang, Lin-Feng; Dong, Zhen; Wang, Feng

2018-04-12

The purpose of this study was to compare the clinical efficacy of anterior cervical discectomy and fusion (ACDF) with Zero-profile device (Zero-p) and traditional cervical plate-and-cage implant in the treatment of symptomatic adjacent segment disease (ASD) and to determine the optimal reoperation procedure. This was a retrospective study of 58 patients with symptomatic ASD after an initial ACDF surgery and who had undergone a reoperation with ACDF with Zero-p (n = 27) and cervical plate-and-cage (n = 31) at our medical center between January 2010 and December 2015. The Japanese Orthopaedic Association score, Neck Disability Index score, Visual Analog Scale score, C2-C7 Cobb angle, and disc height index demonstrated significant improvements compared with the preoperative in both Zero-p and plate-and-cage groups (P < 0.05). However, there were no differences between the two groups (P > 0.05). The reoperation time for the Zero-p group (83.4 ± 18.9 min) was less than that for the plate-and-cage group (96.5 ± 20.1 min), with significant difference (P < 0.05). Five patients (8.6%) had cage subsidence, and 14 patients (24.1%) had dysphagia after the reoperation. There was no statistical significance in the difference between the 2 groups in cage subsidence (P > 0.05). However, the incidence of dysphagia in the plate-and-cage group (38.7%) was higher than in the Zero-p group (7.4%), with a significant difference (P < 0.05). ACDF with Zero-p obtaining the same surgical efficacy, compared with traditional cervical plate-and-cage, can significantly shorten the reoperation time and reduce the incidence of postoperative dysphagia. This option may be preferable for symptomatic patients with ASD qualifying for the anterior approach, in terms of biomechanics and surgical outcomes. Copyright © 2018 Elsevier Inc. All rights reserved.

Camouflage of moderate Class III malocclusions with extraction of lower second molars and mandibular cervical headgear.

PubMed

Mora, Diego Rey; Oberti, Giovanni; Ealo, Martha; Baccetti, Tiziano

2007-01-01

Orthodontic camouflage in patients with slight or moderate skeletal Class III malocclusions, can be obtained through different treatment alternatives. The purpose of this paper is to present a treatment that has not been described in the literature and which consists of the extraction of lower second molars and distal movement of the posterior segments by means of mandibular cervical headgear (MCH) and fixed appliances as a camouflage alternative. The force applied by the MCH was 250 gr per side (14hr/day). The total treatment time was 1 1/2 years. the extraction of lower second molars along with the use of mandibular cervical headgear is a good treatment alternative for camouflage in moderate Class III patients in order to obtain good occlusal relationships without affecting facial esthetics or producing marked dental compensations.

Variable styles of rifting expressed in crustal structure across three rift segments of the Gulf of California

NASA Astrophysics Data System (ADS)

Lizarralde, D. D.; Axen, G. J.; Brown, H. E.; Fletcher, J. M.; Fernandez, A. G.; Harding, A. J.; Holbrook, W. S.; Kent, G. M.; Paramo, P.; Sutherland, F. H.; Umhoefer, P. J.

2007-05-01

We present a summary of results from a crustal-scale seismic experiment conducted in the southern Gulf of California. This experiment, the PESCADOR experiment, imaged crustal structure across three rift segments, the Alarcon, Guaymas, and San José del Cabo to Puerto Vallarta (Cabo-PV) segments, using seismic refraction/wide-angle reflection data acquired with airgun sources and recorded by closely spaced (10-15 km) ocean-bottom seismometers (OBSs). The imaged crustal structure reveals a surprisingly large variation in rifting style and magmatism between these segments: the Alarcon segment is a wide rift with apparently little syn-rift magmatism; the Guaymas segment is a narrow, magmatically robust rift; and the Cabo-PV segment is a narrow, magmatically "normal" rift. Our explanation for the observed variability is non-traditional in that we do not invoke mantle temperature, the factor commonly invoked to explain end-member volcanic and non-volcanic rifted margins, as the source of the considerable, though non-end-member variability we observe. Instead, we invoke mantle depletion related to pre-rift arc volcanism to account for observed wide, magma-poor rifting and mantle fertility and possibly the influence of sediments to account for robust rift and post-rift magmatism. These factors may commonly vary over small lateral spatial scales in regions that have transitioned from convergent to extensional tectonics, as is the case for the Gulf of California and many other rifts. Our hypothesis suggests that substantial lateral variability may exist within the uppermost mantle beneath the Gulf of California today, and it is hoped that ongoing efforts to image upper mantle structure here will provide tests for this hypothesis.

In vitro-analysis of kinematics and intradiscal pressures in cervical arthroplasty versus fusion--A biomechanical study in a sheep model with two semi-constrained prosthesis.

PubMed

Daentzer, Dorothea; Welke, Bastian; Hurschler, Christof; Husmann, Nathalie; Jansen, Christina; Flamme, Christian Heinrich; Richter, Berna Ida

2015-03-24

As an alternative technique to arthrodesis of the cervical spine, total disc replacement (TDR) has increasingly been used with the aim of restoration of the physiological function of the treated and adjacent motions segments. The purpose of this experimental study was to analyze the kinematics of the target level as well as of the adjacent segments, and to measure the pressures in the proximal and distal disc after arthrodesis as well as after arthroplasty with two different semi-constrained types of prosthesis. Twelve cadaveric ovine cervical spines underwent polysegmental (C2-5) multidirectional flexibility testing with a sensor-guided industrial serial robot. Additionally, pressures were recorded in the proximal and distal disc. The following three conditions were tested: (1) intact specimen, (2) single-level arthrodesis C3/4, (3) single-level TDR C3/4 using the Discover® in the first six specimens and the activ® C in the other six cadavers. Statistical analysis was performed for the total range of motion (ROM), the intervertebral ROM (iROM) and the intradiscal pressures (IDP) to compare both the three different conditions as well as the two disc prosthesis among each other. The relative iROM in the target level was always lowered after fusion in the three directions of motion. In almost all cases, the relative iROM of the adjacent segments was almost always higher compared to the physiologic condition. After arthroplasty, we found increased relative iROM in the treated level in comparison to intact state in almost all cases, with relative iROM in the adjacent segments observed to be lower in almost all situations. The IDP in both adjacent discs always increased in flexion and extension after arthrodesis. In all but five cases, the IDP in each of the adjacent level was decreased below the values of the intact specimens after TDR. Overall, in none of the analyzed parameters were statistically significantly differences between both types of prostheses investigated. The results of this biomechanical study indicate that single-level implantation of semi-constrained TDR lead to a certain hypermobility in the treated segments with lowering the ROM in the adjacent levels in almost all situations.

Three-dimensional motion of the uncovertebral joint during head rotation.

PubMed

Nagamoto, Yukitaka; Ishii, Takahiro; Iwasaki, Motoki; Sakaura, Hironobu; Moritomo, Hisao; Fujimori, Takahito; Kashii, Masafumi; Murase, Tsuyoshi; Yoshikawa, Hideki; Sugamoto, Kazuomi

2012-10-01

The uncovertebral joints are peculiar but clinically important anatomical structures of the cervical vertebrae. In the aged or degenerative cervical spine, osteophytes arising from an uncovertebral joint can cause cervical radiculopathy, often necessitating decompression surgery. Although these joints are believed to bear some relationship to head rotation, how the uncovertebral joints work during head rotation remains unclear. The purpose of this study is to elucidate 3D motion of the uncovertebral joints during head rotation. Study participants were 10 healthy volunteers who underwent 3D MRI of the cervical spine in 11 positions during head rotation: neutral (0°) and 15° increments to maximal head rotation on each side (left and right). Relative motions of the cervical spine were calculated by automatically superimposing a segmented 3D MR image of the vertebra in the neutral position over images of each position using the volume registration method. The 3D intervertebral motions of all 10 volunteers were standardized, and the 3D motion of uncovertebral joints was visualized on animations using data for the standardized motion. Inferred contact areas of uncovertebral joints were also calculated using a proximity mapping technique. The 3D animation of uncovertebral joints during head rotation showed that the joints alternate between contact and separation. Inferred contact areas of uncovertebral joints were situated directly lateral at the middle cervical spine and dorsolateral at the lower cervical spine. With increasing angle of rotation, inferred contact areas increased in the middle cervical spine, whereas areas in the lower cervical spine slightly decreased. In this study, the 3D motions of uncovertebral joints during head rotation were depicted precisely for the first time.

Morphometric analysis of the developing pediatric cervical spine.

PubMed

Johnson, Kyle T; Al-Holou, Wajd N; Anderson, Richard C E; Wilson, Thomas J; Karnati, Tejas; Ibrahim, Mohannad; Garton, Hugh J L; Maher, Cormac O

2016-09-01

OBJECTIVE Our understanding of pediatric cervical spine development remains incomplete. The purpose of this analysis was to quantitatively define cervical spine growth in a population of children with normal CT scans. METHODS A total of 1458 children older than 1 year and younger than 18 years of age who had undergone a cervical spine CT scan at the authors' institution were identified. Subjects were separated by sex and age (in years) into 34 groups. Following this assignment, subjects within each group were randomly selected for inclusion until a target of 15 subjects in each group had been measured. Linear measurements were performed on the midsagittal image of the cervical spine. Twenty-three unique measurements were obtained for each subject. RESULTS Data showed that normal vertical growth of the pediatric cervical spine continues up to 18 years of age in boys and 14 years of age in girls. Approximately 75% of the vertical growth occurs throughout the subaxial spine and 25% occurs across the craniovertebral region. The C-2 body is the largest single-segment contributor to vertical growth, but the subaxial vertebral bodies and disc spaces also contribute. Overall vertical growth of the cervical spine throughout childhood is dependent on individual vertebral body growth as well as vertical growth of the disc spaces. The majority of spinal canal diameter growth occurs by 4 years of age. CONCLUSIONS The authors' morphometric analyses establish parameters for normal pediatric cervical spine growth up to 18 years of age. These data should be considered when evaluating children for potential surgical intervention and provide a basis of comparison for studies investigating the effects of cervical spine instrumentation and fusion on subsequent growth.

Cervical intraspinal microstimulation evokes robust forelimb movements before and after injury

NASA Astrophysics Data System (ADS)

Sunshine, Michael D.; Cho, Frances S.; Lockwood, Danielle R.; Fechko, Amber S.; Kasten, Michael R.; Moritz, Chet T.

2013-06-01

Objective. Intraspinal microstimulation (ISMS) is a promising method for reanimating paralyzed limbs following neurological injury. ISMS within the cervical and lumbar spinal cord is capable of evoking a variety of highly-functional movements prior to injury, but the ability of ISMS to evoke forelimb movements after cervical spinal cord injury is unknown. Here we examine the forelimb movements and muscles activated by cervical ISMS both before and after contusion injury. Approach. We documented the forelimb muscles activated and movements evoked via systematic stimulation of the rodent cervical spinal cord both before injury and three, six and nine weeks following a moderate C4/C5 lateralized contusion injury. Animals were anesthetized with isoflurane to permit construction of somatotopic maps of evoked movements and quantify evoked muscle synergies between cervical segments C3 and T1. Main results. When ISMS was delivered to the cervical spinal cord, a variety of responses were observed at 68% of locations tested, with a spatial distribution that generally corresponded to the location of motor neuron pools. Stimulus currents required to achieve movement and the number of sites where movements could be evoked were unchanged by spinal cord injury. A transient shift toward extension-dominated movements and restricted muscle synergies were observed at three and six weeks following injury, respectively. By nine weeks after injury, however, ISMS-evoked patterns were similar to spinally-intact animals. Significance. The results demonstrate the potential for cervical ISMS to reanimate hand and arm function following spinal cord injury. Robust forelimb movements can be evoked both before and during the chronic stages of recovery from a clinically relevant and sustained cervical contusion injury.

Verminous (Strongylus vulgaris) myelitis in a donkey.

PubMed

Mayhew, I G; Brewer, B D; Reinhard, M K; Greiner, E C

1984-01-01

A fifth stage Strongylus vulgaris migrated through the spinal cord of a 2-year-old, male donkey resulting in progressive paraparesis and then tetraplegia. A profound neutrophilic pleocytosis was detected on analysis of cerebrospinal fluid. The parasite appeared to have entered the mid-lumbar spinal cord, migrated to the cranial thoracic segments, exited, then re-entered the spinal cord a few segments craniad. It then traveled further cranially and was found in the third cervical spinal cord segment. Some parts of the lesion were remarkably free from tissue necrosis, hemorrhage and inflammation. Severe granulomatous myelitis with hemorrhage and necrosis were seen at other sites. The latter were quite similar to lesions seen in equine protozoal myeloencephalitis.

Direction-Specific Impairments in Cervical Range of Motion in Women with Chronic Neck Pain: Influence of Head Posture and Gravitationally Induced Torque.

PubMed

Rudolfsson, Thomas; Björklund, Martin; Svedmark, Åsa; Srinivasan, Divya; Djupsjöbacka, Mats

2017-01-01

Cervical range of motion (ROM) is commonly assessed in clinical practice and research. In a previous study we decomposed active cervical sagittal ROM into contributions from lower and upper levels of the cervical spine and found level- and direction-specific impairments in women with chronic non-specific neck pain. The present study aimed to validate these results and investigate if the specific impairments can be explained by the neutral posture (defining zero flexion/extension) or a movement strategy to avoid large gravitationally induced torques on the cervical spine. Kinematics of the head and thorax was assessed in sitting during maximal sagittal cervical flexion/extension (high torque condition) and maximal protraction (low torque condition) in 120 women with chronic non-specific neck pain and 40 controls. We derived the lower and upper cervical angles, and the head centre of mass (HCM), from a 3-segment kinematic model. Neutral head posture was assessed using a standardized procedure. Previous findings of level- and direction-specific impairments in neck pain were confirmed. Neutral head posture was equal between groups and did not explain the direction-specific impairments. The relative magnitude of group difference in HCM migration did not differ between high and low torques conditions, lending no support for our hypothesis that impairments in sagittal ROM are due to torque avoidance behaviour. The direction- and level-specific impairments in cervical sagittal ROM can be generalised to the population of women with non-specific neck pain. Further research is necessary to clarify if torque avoidance behaviour can explain the impairments.

On the Shape of the Common Carotid Artery, with Implications for Blood Velocity Profiles

PubMed Central

Manbachi, Amir; Hoi, Yiemeng; Wasserman, Bruce A.; Lakatta, Edward G.; Steinman, David A

2012-01-01

Clinical and engineering studies typically assume that the common carotid artery (CCA) is straight enough to assume fully developed flow, yet recent studies have demonstrated the presence of skewed velocity profiles. Towards elucidating the influence of mild vascular curvatures on blood flow patterns and atherosclerosis, the present study aimed to characterize the three-dimensional shape of the human CCA. The left and right carotid arteries of 28 participants (62±13 years) in the VALIDATE (Vascular Aging – The Link that Bridges Age to Atherosclerosis) study were digitally segmented from 3D contrast-enhanced magnetic resonance angiograms, from the aortic arch to the carotid bifurcation. Each CCA was divided into nominal cervical and thoracic segments, for which curvatures were estimated by least squares fitting of the respective centerlines to planar arcs. The cervical CCA had mean radius of curvature of 127 mm, corresponding to a mean lumen:curvature radius ratio of 1:50. The thoracic CCA was significantly more curved at 1:16, with the plane of curvature tilted by a mean angle of 25 degrees and rotated close to 90 degrees with respect to that of the cervical CCA. The left CCA was significantly longer and slightly more curved than the right CCA, and there was a weak but significant increase in CCA curvature with age. Computational fluid dynamic (CFD) simulations carried out for idealized CCA geometries derived from these and other measured geometric parameters demonstrated that mild cervical curvature is sufficient to prevent flow from fully developing, independent of the degree of thoracic curvature. These findings reinforce the idea that fully-developed flow may be the exception rather than the rule for the CCA, and perhaps other nominally long and straight vessels. PMID:22031538

Biomechanical testing simulation of a cadaver spine specimen: development and evaluation study.

PubMed

Ahn, Hyung Soo; DiAngelo, Denis J

2007-05-15

This article describes a computer model of the cadaver cervical spine specimen and virtual biomechanical testing. To develop a graphics-oriented, multibody model of a cadaver cervical spine and to build a virtual laboratory simulator for the biomechanical testing using physics-based dynamic simulation techniques. Physics-based computer simulations apply the laws of physics to solid bodies with defined material properties. This technique can be used to create a virtual simulator for the biomechanical testing of a human cadaver spine. An accurate virtual model and simulation would complement tissue-based in vitro studies by providing a consistent test bed with minimal variability and by reducing cost. The geometry of cervical vertebrae was created from computed tomography images. Joints linking adjacent vertebrae were modeled as a triple-joint complex, comprised of intervertebral disc joints in the anterior region, 2 facet joints in the posterior region, and the surrounding ligament structure. A virtual laboratory simulation of an in vitro testing protocol was performed to evaluate the model responses during flexion, extension, and lateral bending. For kinematic evaluation, the rotation of motion segment unit, coupling behaviors, and 3-dimensional helical axes of motion were analyzed. The simulation results were in correlation with the findings of in vitro tests and published data. For kinetic evaluation, the forces of the intervertebral discs and facet joints of each segment were determined and visually animated. This methodology produced a realistic visualization of in vitro experiment, and allowed for the analyses of the kinematics and kinetics of the cadaver cervical spine. With graphical illustrations and animation features, this modeling technique has provided vivid and intuitive information.

In vitro biomechanical comparison after fixed- and mobile-core artificial cervical disc replacement versus fusion

PubMed Central

Lou, Jigang; Li, Yuanchao; Wang, Beiyu; Meng, Yang; Wu, Tingkui; Liu, Hao

2017-01-01

Abstract In vitro biomechanical analysis after cervical disc replacement (CDR) with a novel artificial disc prosthesis (mobile core) was conducted and compared with the intact model, simulated fusion, and CDR with a fixed-core prosthesis. The purpose of this experimental study was to analyze the biomechanical changes after CDR with a novel prosthesis and the differences between fixed- and mobile-core prostheses. Six human cadaveric C2–C7 specimens were biomechanically tested sequentially in 4 different spinal models: intact specimens, simulated fusion, CDR with a fixed-core prosthesis (Discover, DePuy), and CDR with a mobile-core prosthesis (Pretic-I, Trauson). Moments up to 2 Nm with a 75 N follower load were applied in flexion–extension, left and right lateral bending, and left and right axial rotation. The total range of motion (ROM), segmental ROM, and adjacent intradiscal pressure (IDP) were calculated and analyzed in 4 different spinal models, as well as the differences between 2 disc prostheses. Compared with the intact specimens, the total ROM, segmental ROM, and IDP at the adjacent segments showed no significant difference after arthroplasty. Moreover, CDR with a mobile-core prosthesis presented a little higher values of target segment (C5/6) and total ROM than CDR with a fixed-core prosthesis (P > .05). Besides, the difference in IDP at C4/5 after CDR with 2 prostheses was without statistical significance in all the directions of motion. However, the IDP at C6/7 after CDR with a mobile-core prosthesis was lower than CDR with a fixed-core prosthesis in flexion, extension, and lateral bending, with significant difference (P < .05), but not under axial rotation. CDR with a novel prosthesis was effective to maintain the ROM at the target segment and did not affect the ROM and IDP at the adjacent segments. Moreover, CDR with a mobile-core prosthesis presented a little higher values of target segment and total ROM, but lower IDP at the inferior adjacent segment than CDR with a fixed-core prosthesis. PMID:29019902

Geology of the north end of the Ruby Range, southwestern Montana

USGS Publications Warehouse

Tysdal, Russell G.

1970-01-01

This study consists of two parts: stratigraphy and sedimentation, and structure of rocks in the northern one-third of the Ruby Range of southwestern Montana. Detailed studies of Cambrian marine dolomite rocks in the Red Lion Formation and in the upper part of the Pilgrim Limestone resulted in their division into distinct rock units, termed lithofacies. These lithofacies contain features suggestive of subtidal, intertidal, and supratidal environments similar to those presently forming in the Persian Gulf. Stromatolltic structures occurring in the uppermost part of the Red Lion Formation are similar to those presently forming in Shark Bay, Australia. The Ruby Range within the map area is broken into a series of northwest-plunging basement (Precambrian metamorphic rock) blocks, differentially uplifted during the Cretaceous-Tertiary orogenic period. These blocks are bordered by upthrust faults, which are nearly vertical in their lower segments and are .low-angle in their uppermost parts. Asymmetrical folds in Paleozoic sedimentary rocks formed in response to the differential uplift of the blocks; thus they too plunge to the northwest. Displaced masses of rock border the range on the three sides within the map area and are interpreted as gravity-slide features resulting from uplift of the range. Normal faulting began blocking out the present range margins by Oligocene time.

Short communication: Traits unique to genus Homo within primates at the cervical spine (C2-C7).

PubMed

Rios, Luis; Muñoz, Alexandra; Cardoso, Hugo; Pastor, Francisco

2014-05-01

From a comparative study of 222 human and 261 nonhuman primates complete cervical spines, two bony variants associated to the course of the vertebral artery are proposed as unique to genus Homo within primates. First, the opening of the foramen transversarium at C2, a trait present at low frequency in humans (3 to 5.6%). Second, the presence of a bipartite foramen transversarium in the cervical segment C3-C6, a trait that can be observed fully formed in human fetal skeletons, with a clear frequency pattern along the cervical spine (C3>C4>C5>C6

Choice of surgical approach for ossification of the posterior longitudinal ligament in combination with cervical disc hernia

PubMed Central

Yang, Hai-song; Lu, Xu-hua; Yang, Li–li; Yan, Wang-jun; Yuan, Wen; Chen, Yu

2009-01-01

Ossification of the posterior longitudinal ligament (OPLL) is a common spinal disorder that presents with or without cervical myelopathy. Furthermore, there is evidence suggesting that OPLL often coexists with cervical disc hernia (CDH), and that the latter is the more important compression factor. To raise the awareness of CDH in OPLL for spinal surgeons, we performed a retrospective study on 142 patients with radiologically proven OPLL who had received surgery between January 2004 and January 2008 in our hospital. Plain radiograph, three-dimensional computed tomography construction (3D CT), and magnetic resonance imaging (MRI) of the cervical spine were all performed. Twenty-six patients with obvious CDH (15 of segmental-type, nine of mixed-type, two of continuous-type) were selected via clinical and radiographic features, and intraoperative findings. By MRI, the most commonly involved level was C5/6, followed by C3/4, C4/5, and C6/7. The areas of greatest spinal cord compression were at the disc levels because of herniated cervical discs. Eight patients were decompressed via anterior cervical discectomy and fusion (ACDF), 13 patients via anterior cervical corpectomy and fusion (ACCF), and five patients via ACDF combined with posterior laminectomy and fusion. The outcomes were all favorable. In conclusion, surgeons should consider the potential for CDH when performing spinal cord decompression and deciding the surgical approach in patients presenting with OPLL. PMID:20012451

Clinical comparison of Zero-profile interbody fusion device and anterior cervical plate interbody fusion in treating cervical spondylosis.

PubMed

Yan, Bin; Nie, Lin

2015-01-01

the aim of the study was to compare the clinical effect of Zero-profile interbody fusion device (Zero-P) with anterior cervical plate interbody fusion system (PCB) in treating cervical spondylosis. a total of 98 patients with cervical spondylosis (110 segments) in February 2011 to January 2013 were included in our hospital. All participants were randomly divided into observation group and control group with 49 cases in each group. The observation group was treated with Zero-P, while the control group received PCB treatment. Comparison of the two groups in neurological function score (JOA), pain visual analogue scale (VAS), the neck disability index (NDI), quality of life score (SF-36) and cervical curvature (Cobb angle) change were recorded and analyzed before and after treatment. The observation group was found with 90% excellent and good rate, which was higher than that of the control group (80%). Dysphagia rate in observational group was 16.33% (8/49), which was significantly less than that in control group (46.94%). Operation time and bleeding volume in the observation group was less than those in control group. Postoperative improvements of JOA score, VAS score, and NDI in observational group were also significantly better than that in control group (P<0.05). The clinical effect of Zero-P and PCB for the treatment of cervical spondylosis was quite fair, but Zero-P showed a better therapeutic effect with improvement of life quality.

The NEtherlands Cervical Kinematics (NECK) trial. Cost-effectiveness of anterior cervical discectomy with or without interbody fusion and arthroplasty in the treatment of cervical disc herniation; a double-blind randomised multicenter study.

PubMed

Arts, Mark P; Brand, Ronald; van den Akker, Elske; Koes, Bart W; Peul, Wilco C

2010-06-16

Patients with cervical radicular syndrome due to disc herniation refractory to conservative treatment are offered surgical treatment. Anterior cervical discectomy is the standard procedure, often in combination with interbody fusion. Accelerated adjacent disc degeneration is a known entity on the long term. Recently, cervical disc prostheses are developed to maintain motion and possibly reduce the incidence of adjacent disc degeneration. A comparative cost-effectiveness study focused on adjacent segment degeneration and functional outcome has not been performed yet. We present the design of the NECK trial, a randomised study on cost-effectiveness of anterior cervical discectomy with or without interbody fusion and arthroplasty in patients with cervical disc herniation. Patients (age 18-65 years) presenting with radicular signs due to single level cervical disc herniation lasting more than 8 weeks are included. Patients will be randomised into 3 groups: anterior discectomy only, anterior discectomy with interbody fusion, and anterior discectomy with disc prosthesis. The primary outcome measure is symptomatic adjacent disc degeneration at 2 and 5 years after surgery. Other outcome parameters will be the Neck Disability Index, perceived recovery, arm and neck pain, complications, re-operations, quality of life, job satisfaction, anxiety and depression assessment, medical consumption, absenteeism, and costs. The study is a randomised prospective multicenter trial, in which 3 surgical techniques are compared in a parallel group design. Patients and research nurses will be kept blinded of the allocated treatment for 2 years. The follow-up period is 5 years. Currently, anterior cervical discectomy with fusion is the golden standard in the surgical treatment of cervical disc herniation. Whether additional interbody fusion or disc prosthesis is necessary and cost-effective will be determined by this trial. Netherlands Trial Register NTR1289.

Comparison of Cervical Spine Anatomy in Calves, Pigs and Humans.

PubMed

Sheng, Sun-Ren; Xu, Hua-Zi; Wang, Yong-Li; Zhu, Qing-An; Mao, Fang-Min; Lin, Yan; Wang, Xiang-Yang

2016-01-01

Animals are commonly used to model the human spine for in vitro and in vivo experiments. Many studies have investigated similarities and differences between animals and humans in the lumbar and thoracic vertebrae. However, a quantitative anatomic comparison of calf, pig, and human cervical spines has not been reported. To compare fundamental structural similarities and differences in vertebral bodies from the cervical spines of commonly used experimental animal models and humans. Anatomical morphometric analysis was performed on cervical vertebra specimens harvested from humans and two common large animals (i.e., calves and pigs). Multiple morphometric parameters were directly measured from cervical spine specimens of twelve pigs, twelve calves and twelve human adult cadavers. The following anatomical parameters were measured: vertebral body width (VBW), vertebral body depth (VBD), vertebral body height (VBH), spinal canal width (SCW), spinal canal depth (SCD), pedicle width (PW), pedicle depth (PD), pedicle inclination (PI), dens width (DW), dens depth (DD), total vertebral width (TVW), and total vertebral depth (TVD). The atlantoaxial (C1-2) joint in pigs is similar to that in humans and could serve as a human substitute. The pig cervical spine is highly similar to the human cervical spine, except for two large transverse processes in the anterior regions ofC4-C6. The width and depth of the calf odontoid process were larger than those in humans. VBW and VBD of calf cervical vertebrae were larger than those in humans, but the spinal canal was smaller. Calf C7 was relatively similar to human C7, thus, it may be a good substitute. Pig cervical vertebrae were more suitable human substitutions than calf cervical vertebrae, especially with respect to C1, C2, and C7. The biomechanical properties of nerve vascular anatomy and various segment functions in pig and calf cervical vertebrae must be considered when selecting an animal model for research on the spine.

The NEtherlands Cervical Kinematics (NECK) Trial. Cost-effectiveness of anterior cervical discectomy with or without interbody fusion and arthroplasty in the treatment of cervical disc herniation; a double-blind randomised multicenter study

PubMed Central

2010-01-01

Background Patients with cervical radicular syndrome due to disc herniation refractory to conservative treatment are offered surgical treatment. Anterior cervical discectomy is the standard procedure, often in combination with interbody fusion. Accelerated adjacent disc degeneration is a known entity on the long term. Recently, cervical disc prostheses are developed to maintain motion and possibly reduce the incidence of adjacent disc degeneration. A comparative cost-effectiveness study focused on adjacent segment degeneration and functional outcome has not been performed yet. We present the design of the NECK trial, a randomised study on cost-effectiveness of anterior cervical discectomy with or without interbody fusion and arthroplasty in patients with cervical disc herniation. Methods/Design Patients (age 18-65 years) presenting with radicular signs due to single level cervical disc herniation lasting more than 8 weeks are included. Patients will be randomised into 3 groups: anterior discectomy only, anterior discectomy with interbody fusion, and anterior discectomy with disc prosthesis. The primary outcome measure is symptomatic adjacent disc degeneration at 2 and 5 years after surgery. Other outcome parameters will be the Neck Disability Index, perceived recovery, arm and neck pain, complications, re-operations, quality of life, job satisfaction, anxiety and depression assessment, medical consumption, absenteeism, and costs. The study is a randomised prospective multicenter trial, in which 3 surgical techniques are compared in a parallel group design. Patients and research nurses will be kept blinded of the allocated treatment for 2 years. The follow-up period is 5 years. Discussion Currently, anterior cervical discectomy with fusion is the golden standard in the surgical treatment of cervical disc herniation. Whether additional interbody fusion or disc prothesis is necessary and cost-effective will be determined by this trial. Trial Registration Netherlands Trial Register NTR1289 PMID:20553591

Cervical arthroplasty: a critical review of the literature.

PubMed

Alvin, Matthew D; Abbott, E Emily; Lubelski, Daniel; Kuhns, Benjamin; Nowacki, Amy S; Steinmetz, Michael P; Benzel, Edward C; Mroz, Thomas E

2014-09-01

Cervical disc arthroplasty (CDA) is a motion-preserving procedure that is an alternative to fusion. Proponents of arthroplasty assert that it will maintain cervical motion and prevent or reduce adjacent segment degeneration. Accordingly, CDA, compared with fusion, would have the potential to improve clinical outcomes. Published studies have varying conclusions on whether CDA reduces complications and/or improves outcomes. As many of these previous studies have been funded by CDA manufacturers, we wanted to ascertain whether there was a greater likelihood for these studies to report positive results. To critically assess the available literature on cervical arthroplasty with a focus on the time of publication and conflict of interest (COI). Review of the literature. All clinical articles about CDA published in English through August 1, 2013 were identified on Medline. Any article that presented CDA clinical results was included. Study design, sample size, type of disc, length of follow-up, use of statistical analysis, quality-of-life (QOL) outcome scores, COI, and complications were recorded. A meta-analysis was conducted stratifying studies by COI and publication date to identify differences in complication rates reported. Seventy-four studies were included that investigated 8 types of disc prosthesis and 22 met the criteria for a randomized controlled trial (RCT). All Level Ib RCTs reported superior quality-of-life outcomes for CDA versus anterior cervical discectomy and fusion (ACDF) at 24 months. Fifty of the 74 articles (68%) had a disclosure section, including all Level Ib RCTs, which had significant COIs related to the respective studies. Those studies without a COI reported mean weighted average adjacent segment disease rates of 6.3% with CDA and 6.2% with ACDF. In contrast, the reverse was reported by studies with a COI, for which the averages were 2.5% with CDA and 6.3% with ACDF. Those studies with a COI (n=31) had an overall weighted average heterotopic ossification rate of 22%, whereas those studies with no COI (n=43) had a rate of 46%. Associated COIs did not influence QOL outcomes. Conflicts of interest were more likely to be present in studies published after 2008, and those with a COI reported greater adjacent segment disease rates for ACDF than CDA. In addition, heterotopic ossification rates were much lower in studies with COI versus those without COI. Thus, COIs did not affect QOL outcomes but were associated with lower complication rates. Copyright © 2014 Elsevier Inc. All rights reserved.

The cat vertebral column: stance configuration and range of motion

NASA Technical Reports Server (NTRS)

Macpherson, J. M.; Ye, Y.; Peterson, B. W. (Principal Investigator)

1998-01-01

This study examined the configuration of the vertebral column of the cat during independent stance and in various flexed positions. The range of motion in the sagittal plane is similar across most thoracic and lumbar joints, with the exception of a lesser range at the transition region from thoracic-type to lumbar-type vertebrae. The upper thoracic column exhibits most of its range in dorsiflexion and the lower thoracic and lumbar in ventroflexion. Lateral flexion is limited to less than 5 degrees at all segments. The range in torsion is almost 180 degrees and occurs primarily in the midthoracic region, T4-T11. Contrary to the depiction in most atlases, the standing cat exhibits several curvatures, including a mild dorsiflexion in the lower lumbar segments, a marked ventroflexion in the lower thoracic and upper lumbar segments, and a profound dorsiflexion in the upper thoracic (above T9) and cervical segments. The curvatures are not significantly changed by altering stance distance but are affected by head posture. During stance, the top of the scapula lies well above the spines of the thoracic vertebrae, and the glenohumeral joint is just below the bodies of vertebrae T3-T5. Using a simple static model of the vertebral column in the sagittal plane, it was estimated that the bending moment due to gravity is bimodal with a dorsiflexion moment in the lower thoracic and lumbar region and a ventroflexion moment in the upper thoracic and cervical region. Given the bending moments and the position of the scapula during stance, it is proposed that two groups of scapular muscles provide the major antigravity support for the head and anterior trunk. Levator scapulae and serratus ventralis form the lateral group, inserting on the lateral processes of cervical vertebrae and on the ribs. The major and minor rhomboids form the medial group, inserting on the spinous tips of vertebrae from C4 to T4. It is also proposed that the hypaxial muscles, psoas major, minor, and quadratus lumborum could support the lumbar trunk during stance.

Long-term results of anterior cervical corpectomy and fusion with nano-hydroxyapatite/polyamide 66 strut for cervical spondylotic myelopathy

NASA Astrophysics Data System (ADS)

Zhang, Yuan; Deng, Xu; Jiang, Dianming; Luo, Xiaoji; Tang, Ke; Zhao, Zenghui; Zhong, Weiyang; Lei, Tao; Quan, Zhengxue

2016-05-01

To assess the long-term clinical and radiographic outcomes of anterior cervical corpectomy and fusion (ACCF) with a neotype nano-hydroxyapatite/polyamide 66 (n-HA/PA66) strut in the treatment of cervical spondylotic myelopathy (CSM). Fifty patients with CSM who underwent 1- or 2-level ACCF with n-HA/PA66 struts were retrospectively investigated. With a mean follow-up of 79.6 months, the overall mean JOA score, VAS and cervical alignment were improved significantly. At last follow-up, the fusion rate was 98%, and the subsidence rate of the n-HA/PA66 strut was 8%. The “radiolucent gap” at the interface between the n-HA/PA66 strut and the vertebra was further noted to evaluate the osteoconductivity and osseointegration of the strut, and the incidence of it was 62% at the last follow-up. Three patients suffered symptomatic adjacent segment degeneration (ASD). No significant difference was detected in the outcomes between 1- and 2-level corpectomy at follow-ups. In conclusion, the satisfactory outcomes in this study indicated that the n-HA/PA66 strut was an effective graft for cervical reconstruction. Moreover, the osteoconductivity and osseointegration of the strut is still need to be optimized for future clinical application owing to the notably presence of “radiolucent gap” in present study.

Effects of Lateral Mass Screw Rod Fixation to the Stability of Cervical Spine after Laminectomy

NASA Astrophysics Data System (ADS)

Rosli, Ruwaida; Kashani, Jamal; Kadir, Mohammed Rafiq Abdul

There are many cases of injury in the cervical spine due to degenerative disorder, trauma or instability. This condition may produce pressure on the spinal cord or on the nerve coming from the spine. The aim of this study was, to analyze the stabilization of the cervical spine after undergoing laminectomy via computational simulation. For that purpose, a three-dimensional finite element (FE) model for the multilevel cervical spine segment (C1-C7) was developed using computed tomography (CT) data. There are various decompression techniques that can be applied to overcome the injury. Usually, decompression procedures will create an unstable spine. Therefore, in these situations, the spine is often surgically restabilized by using fusion and instrumentation. In this study, a lateral mass screw-rod fixation was created to stabilize the cervical spine after laminectomy. Material properties of the titanium alloy were assigned on the implants. The requirements moments and boundary conditions were applied on simulated implanted bone. Result showed that the bone without implant has a higher flexion and extension angle in comparison to the bone with implant under applied 1Nm moment. The bone without implant has maximum stress distribution at the vertebrae and ligaments. However, the bone with implant has maximum stress distribution at the screws and rods. Overall, the lateral mass screw-rod fixation provides stability to the cervical spine after undergoing laminectomy.

Automatic 3D segmentation of spinal cord MRI using propagated deformable models

NASA Astrophysics Data System (ADS)

De Leener, B.; Cohen-Adad, J.; Kadoury, S.

2014-03-01

Spinal cord diseases or injuries can cause dysfunction of the sensory and locomotor systems. Segmentation of the spinal cord provides measures of atrophy and allows group analysis of multi-parametric MRI via inter-subject registration to a template. All these measures were shown to improve diagnostic and surgical intervention. We developed a framework to automatically segment the spinal cord on T2-weighted MR images, based on the propagation of a deformable model. The algorithm is divided into three parts: first, an initialization step detects the spinal cord position and orientation by using the elliptical Hough transform on multiple adjacent axial slices to produce an initial tubular mesh. Second, a low-resolution deformable model is iteratively propagated along the spinal cord. To deal with highly variable contrast levels between the spinal cord and the cerebrospinal fluid, the deformation is coupled with a contrast adaptation at each iteration. Third, a refinement process and a global deformation are applied on the low-resolution mesh to provide an accurate segmentation of the spinal cord. Our method was evaluated against a semi-automatic edge-based snake method implemented in ITK-SNAP (with heavy manual adjustment) by computing the 3D Dice coefficient, mean and maximum distance errors. Accuracy and robustness were assessed from 8 healthy subjects. Each subject had two volumes: one at the cervical and one at the thoracolumbar region. Results show a precision of 0.30 +/- 0.05 mm (mean absolute distance error) in the cervical region and 0.27 +/- 0.06 mm in the thoracolumbar region. The 3D Dice coefficient was of 0.93 for both regions.

Risk factors associated with upper extremity palsy after expansive open-door laminoplasty for cervical myelopathy.

PubMed

Wu, Feng L; Sun, Yu; Pan, Sheng F; Zhang, Li; Liu, Zhong J

2014-06-01

Postoperative paresis, so-called C5 palsy, of the upper extremities is a common complication of cervical surgery. There have been several reports about upper extremity palsy after cervical laminoplasty for patients with cervical myelopathy. However, the possible risk factors remain unclear. To investigate the factors associated with the development of upper extremity palsy after expansive open-door laminoplasty for cervical myelopathy. A retrospective review of medical records. A total of 102 patients (76 men and 26 women) were eligible for analysis in this study. The mean age of the patients was 58.7 years (range 35-81 years). Sixteen patients (13 men and 3 women, average age 62.8 years) with palsy were categorized as Group P, and eighty-six patients (63 men and 23 women, average age 57.8 years) without palsy as Group C. The demographic data collected from both groups were age, sex, duration of symptoms, disease, and type of surgical procedure. Cervical curvature index, width of the intervertebral foramen (WIF) at C5, anterior protrusion of the superior articular process (APSAP), number of compressed segments, high-signal intensity zone at the level corresponding to C3-C5 (HIZ:C3-C5), and posterior shift of the spinal cord (PSSC) were also evaluated. Upper extremity palsy was defined as weakness of Grade 4 or less of the key muscles in the upper extremity by manual muscle test without any deterioration of myelopathic symptoms after surgery. Comparisons were made with screen for the parameters with significant differences, and then we further analyzed these parameters by logistic regression analysis (the forward method) to verify the risk factors of the upper extremity palsy. Significant differences in diagnosis, the type of procedure, WIF, APSAP, and HIZ:C3-C5 were observed between the two groups. No statistical difference in PSSC between the groups was noted (2.06 vs. 2.53 mm, p=.247). In logistic regression analysis, ossification of the posterior longitudinal ligament (OPLL), cervical open-door laminoplasty together with posterior instrumented fusion (CLP+PIF), and WIF were found to be significant risk factors for postoperative upper extremity palsy. Patients with preoperative foraminal stenosis, OPLL, and additional iatrogenic foraminal stenosis because of CLP+PIF were more likely to develop postoperative upper extremity palsy. Attention should be given to the WIF determined on preoperative computed tomography of the C5 root. To prevent iatrogenic foraminal stenosis, appropriate distraction between spine segments should be provided during placement of the rod. Copyright © 2014 Elsevier Inc. All rights reserved.

Cervical intradural disc herniation.

PubMed

Iwamura, Y; Onari, K; Kondo, S; Inasaka, R; Horii, H

2001-03-15

A case report of anterior en bloc resected cervical intradural disc herniation and a review of the literature. To discuss the pathogenesis of cervical intradural disc herniation. Including this study case, only 17 cases of cervical intradural disc herniation have been reported. There have been few detailed reports concerning the pathogenesis of cervical intradural disc herniation. A cervical intradural disc herniation at C6-C7, with localized hypertrophy and segmentally ossified posterior longitudinal ligament, is reported in a 45-year-old man who had Brown-Sequard syndrome diagnosed on neurologic examination. Neuroradiologic, operative, and histologic findings, particularly the pathology of the anterior en bloc resected posterior vertebral portion of C6 and C7, were evaluated for discussion of the pathogenesis. Adhesion of dura mater and hypertrophic posterior longitudinal ligament was observed around a perforated portion of the herniated disc, and histologic study showed irregularity in fiber alignment accompanied by scattered inflammatory cell infiltration and hypertrophy in the posterior longitudinal ligament. The cervical intradural disc herniation was removed successfully and followed by C5-Th1 anterior interbody fusion with fibular strut graft. Neurologic recovery was complete except for minor residual sensory disturbance in the leg 7 years after the surgery. Cervical intradural disc herniation is an extremely rare condition. The pathogenesis remains obscure. Only 16 cases have been reported in the literature, and there has been little discussion concerning the local pathology of the herniated portion. The pathogenesis of the disease in the patient reported here was considered to be the adhesion and fragility of dura mater and posterior longitudinal ligament. This was caused by hypertrophy, with chronic inflammation and ossification of the posterior longitudinal ligament sustaining chronic mechanical irritation to the dura mater, leading to perforation of the herniated disc by an accidental force.

Direction-Specific Impairments in Cervical Range of Motion in Women with Chronic Neck Pain: Influence of Head Posture and Gravitationally Induced Torque

PubMed Central

Björklund, Martin; Svedmark, Åsa; Srinivasan, Divya; Djupsjöbacka, Mats

2017-01-01

Background Cervical range of motion (ROM) is commonly assessed in clinical practice and research. In a previous study we decomposed active cervical sagittal ROM into contributions from lower and upper levels of the cervical spine and found level- and direction-specific impairments in women with chronic non-specific neck pain. The present study aimed to validate these results and investigate if the specific impairments can be explained by the neutral posture (defining zero flexion/extension) or a movement strategy to avoid large gravitationally induced torques on the cervical spine. Methods Kinematics of the head and thorax was assessed in sitting during maximal sagittal cervical flexion/extension (high torque condition) and maximal protraction (low torque condition) in 120 women with chronic non-specific neck pain and 40 controls. We derived the lower and upper cervical angles, and the head centre of mass (HCM), from a 3-segment kinematic model. Neutral head posture was assessed using a standardized procedure. Findings Previous findings of level- and direction-specific impairments in neck pain were confirmed. Neutral head posture was equal between groups and did not explain the direction-specific impairments. The relative magnitude of group difference in HCM migration did not differ between high and low torques conditions, lending no support for our hypothesis that impairments in sagittal ROM are due to torque avoidance behaviour. Interpretation The direction- and level-specific impairments in cervical sagittal ROM can be generalised to the population of women with non-specific neck pain. Further research is necessary to clarify if torque avoidance behaviour can explain the impairments. PMID:28099504

Novel multiplexed low coherence interferometry endoscopic probe for analyzing the cervical epithelium in vivo (Conference Presentation)

NASA Astrophysics Data System (ADS)

Ho, Derek; Chu, Kengyeh K.; Crose, Michael; Desoto, Michael; Peters, Jennifer J.; Murtha, Amy P.; Wax, Adam

2017-02-01

The cervix is primarily composed of two types of epithelium: stratified squamous ectocervix and simple columnar endocervix. In between these two layers lies a metaplastic squamocolumnar junction commonly referred to as the transformation zone (T-zone). During puberty, the cervical epithelium undergoes dynamic changes including cervical ectropion and increased area and rates of metaplasia. Although these metaplastic changes have been linked to higher incidence of cervical cancer among young women, research in this field has been limited to surface analysis using computerized planimetry of colopophotographs. Here, we present a novel multiplexed low coherence interferometry (mLCI) system for interrogating the cervical epithelium. The system is comprised of 6 parallel Mach-Zehnder interferometers in a time-multiplexed configuration that increases throughput by 6-fold to realize a combined 36-channel acquisition. A custom designed endoscopic handheld probe is used to collect sparsely sampled, depth-resolved scattering intensity profiles (A-scans) from a large field of view (25 x 25 mm) on the cervical epithelium in vivo. The instrument incorporates white light imaging through a plastic fiber bundle to co-register the mLCI A-scans to colpophotographs which are analyzed by a clinician to manually segment the cervical epithelium. Our preliminary data shows significant differences in characteristic A-scans from endocervical and ectocervical epithelium. These results demonstrate the feasibility of using mLCI as both a research tool for studying the relationship between cervical ectopy and cancer as well as a clinical instrument for identifying the at-risk T-zone on the cervix in vivo as a means to improve biopsy targeting. Further analysis will be performed to develop an algorithm for distinguishing the mLCI A-scans of endocervical, ectocervical, and metaplastic epithelium in real time.

The incidence of noncontiguous spinal fractures and other traumatic injuries associated with cervical spine fractures: a 10-year experience at an academic medical center.

PubMed

Miller, Christopher P; Brubacher, Jacob W; Biswas, Debdut; Lawrence, Brandon D; Whang, Peter G; Grauer, Jonathan N

2011-09-01

Retrospective medical record review. The purpose of this study was to describe the incidence of other injuries that commonly occur in conjunction with cervical spine fractures and dislocations. Cervical spine fractures are often associated with other significant traumatic conditions, which may also require prompt diagnosis and management. However, the relative incidences of the injuries that occur in conjunction with various cervical spine fractures have not been well documented. The radiographic reports of all patients who underwent CT scans of the cervical spine at a single level 1 trauma center over a 10-year period were reviewed. The medical records of individuals with acute, nonpenetrating fractures of the cervical spine were further assessed for any associated traumatic pathology including noncontiguous spine injuries and those affecting other organ systems (i.e., head and neck, intrathoracic, intra-abdominal/pelvic, and nonspinal orthopedic disorders). A total of 13,896 CT scans of the cervical spine were performed during this 10-year period of which 492 revealed acute fractures and/or dislocations. Of these subjects, 60% had sustained at least one additional injury. Overall, 57% were noted to have extraspinal injuries (34% head and neck, 17% intrathoracic, 10% intra-abdominal/pelvic, and 30% nonspinal orthopedic conditions) and noncontiguous spinal trauma was present in 19% of these cases (8% cervical injuries, 8% thoracic, and 6% lumbar). In general, the rates of associated injuries observed with occipital condyle and C7 fractures were significantly higher than those recorded for other cervical segments. For patients with a known history of cervical spine trauma, the frequencies of associated injuries were similar across all levels of the cervical spine with the exception of the injuries to the craniocervical junctions. In practice, this means that injuries to the cervical spine can likely be grouped together when considering other possible associated injuries. Further elucidation of these injury patterns will likely be useful for facilitating the expedient evaluation and proper management of these individuals.

Congenital cervical kyphosis in two young sighthounds.

PubMed

Forterre, F; Casoni, D; Tomek, A; Karli, P; Howard, J; Precht, C

2015-01-01

Cervical vertebral (C) malformation is rarely reported in large breed dogs. Congenital cervical kyphosis (CCK) may result from defects of vertebral segmentation, failure of formation or both. This report describes two cases of C3-C4 CCK in young sighthounds, treated surgically. An 18-month-old female Deerhound and a six-week-old female Borzoi dog were presented because of the complaints of reluctance to exercise and signs of of neck pain. Both dogs were neurologically normal. Diagnostic imaging revealed C3-C4 deformity, moderate kyphosis, and spinal canal stenosis associated with chronic spinal cord pressure atrophy. Both dogs underwent surgical treatment. A staged two-step surgery starting with dorsal decompression was elected in the Deerhound. After the first surgical procedure, the dog developed focal myelomalacia and phrenic nerve paralysis and was euthanatized. A ventral distraction-fusion technique with two locking plates was performed in the Borzoi. This patient recovered uneventfully and long-term follow-up computed tomography revealed complete spondylodesis. Until now, CCK has only been described in sighthounds. Congenital cervical kyphosis might be considered a differential diagnosis in these breeds that are presented with signs of cervical pain. Ventral realignment-fusion and bone grafting may be considered for surgical treatment, although the earliest age at which this procedure can and should be performed remains unclear.

E6-associated transcription patterns in human papilloma virus 16-positive cervical tissues.

PubMed

Lin, Kezhi; Lu, Xulian; Chen, Jun; Zou, Ruanmin; Zhang, Lifang; Xue, Xiangyang

2015-01-01

The change in transcription pattern induced by post-transcriptional RNA splicing is an important mechanism in the regulation of the early gene expression of human papilloma virus (HPV). The present study was conducted to establish a method to specifically amplify HPV-16 E6-associated transcripts. The E6-related transcripts from 63 HPV-16-positive cervical tumor tissue samples were amplified, consisting of eight cases of low-risk intraepithelial lesions, 38 cases of high-risk intraepithelial lesions and 17 cases of cervical cancer (CxCa). The appropriate amplified segments were recovered following agarose gel electrophoresis, and subjected to further sequencing and sequence alignment analysis. Six groups of E6 transcription patterns were identified from HPV-16-positive cervical tumor tissue, including five newly-discovered transcripts. Different HPV-16 E6-associated transcription patterns were detected during the development of CxCa. Over the course of the progression of the low-grade squamous intraepithelial lesions to CxCa, the specific HPV-16 E6-associated transcription patterns and the dominant transcripts were all different. As indicated by this study, the transcription pattern of the E6 early gene of HPV-16 was closely associated with the stages of cervical carcinogenesis, and may also be involved in the development of CxCa.

Do stand-alone interbody spacers with integrated screws provide adequate segmental stability for multilevel cervical arthrodesis?

PubMed

Paik, Haines; Kang, Daniel G; Lehman, Ronald A; Cardoso, Mario J; Gaume, Rachel E; Ambati, Divya V; Dmitriev, Anton E

2014-08-01

Some postoperative complications after anterior cervical fusions have been attributed to anterior cervical plate (ACP) profiles and the necessary wide operative exposure for their insertion. Consequently, low-profile stand-alone interbody spacers with integrated screws (SIS) have been developed. Although SIS constructs have demonstrated similar biomechanical stability to the ACP in single-level fusions, their role as a stand-alone device in multilevel reconstructions has not been thoroughly evaluated. To evaluate the acute segmental stability afforded by an SIS device compared with the traditional ACP in the setting of a multilevel cervical arthrodesis. In vitro human cadaveric biomechanical analysis. Thirteen human cadaveric cervical spines (C2-T1) were nondestructively tested with a custom 6 df spine simulator under axial rotation, flexion-extension, and lateral bending loading. After intact analysis, eight single-levels (C4-C5/C6-C7) from four specimens were instrumented and tested with ACP and SIS. Nine specimens were tested with C5-C7 SIS, C5-C7 ACP, C4-C7 ACP, C4-C7 ACP+posterior fixation, C4-C7 SIS, and C4-C7 SIS+posterior fixation. Testing order was randomized with each additional level instrumented. Full range of motion (ROM) data were obtained and analyzed by each loading modality, using mean comparisons with repeated measures analysis of variance. Paired t tests were used for post hoc analysis with Sidak correction for multiple comparisons. No significant difference in ROM was noted between the ACP and SIS for single-level fixation (p>.05). For multisegment reconstructions (two and three levels), the ACP proved superior to SIS and intact condition, with significantly lower ROM in all planes (p<.05). When either the three-level SIS or ACP constructs were supplemented with posterior lateral mass fixation, there was a greater than 80% reduction in ROM under all testing modalities (p<.05), with no significant difference between the ACP and SIS constructs (p>.05). The SIS device may be a reasonable option as a stand-alone device for single-level fixation. However, SIS devices should be used with careful consideration in the setting of multilevel cervical fusion. However, when supplemented with posterior fixation, SIS devices are a sound biomechanical alternative to ACP for multilevel fusion constructs. Published by Elsevier Inc.

Regeneration of Surgically Excised Segments of Dog Esophagus using Biodegradable PLA Hollow Organ Grafts,

DTIC Science & Technology

1980-06-01

desiccator prior to use. 107 w° *GROWER, CUTRIGHT and RUSSELL thane general anesthesia . By a combination of sharp and blunt dissection the cervical...Bhaskar, S.N., and Augsburg, J.K. A Biodegradable Intraosseous Appliance in the Treatment of Mandibular Fractures. J. Oral Surg. 30:344-348, 1972. 14

Degenerative changes of the canine cervical spine after discectomy procedures, an in vivo study.

PubMed

Grunert, Peter; Moriguchi, Yu; Grossbard, Brian P; Ricart Arbona, Rodolfo J; Bonassar, Lawrence J; Härtl, Roger

2017-06-23

Discectomies are a common surgical treatment for disc herniations in the canine spine. However, the effect of these procedures on intervertebral disc tissue is not fully understood. The objective of this study was to assess degenerative changes of cervical spinal segments undergoing discectomy procedures, in vivo. Discectomies led to a 60% drop in disc height and 24% drop in foraminal height. Segments did not fuse but showed osteophyte formation as well as endplate sclerosis. MR imaging revealed terminal degenerative changes with collapse of the disc space and loss of T2 signal intensity. The endplates showed degenerative type II Modic changes. Quantitative MR imaging revealed that over 95% of Nucleus Pulposus tissue was extracted and that the nuclear as well as overall disc hydration significantly decreased. Histology confirmed terminal degenerative changes with loss of NP tissue, loss of Annulus Fibrosus organization and loss of cartilage endplate tissue. The bony endplate displayed sclerotic changes. Discectomies lead to terminal degenerative changes. Therefore, these procedures should be indicated with caution specifically when performed for prophylactic purposes.

A biomechanical study of artificial cervical discs using computer simulation.

PubMed

Ahn, Hyung Soo; DiAngelo, Denis J

2008-04-15

A virtual simulation model of the subaxial cervical spine was used to study the biomechanical effects of various disc prosthesis designs. To study the biomechanics of different design features of cervical disc arthroplasty devices. Disc arthroplasty is an alternative approach to cervical fusion surgery for restoring and maintaining motion at a diseased spinal segment. Different types of cervical disc arthroplasty devices exist and vary based on their placement and degrees of motion offered. A virtual dynamic model of the subaxial cervical spine was used to study 3 different prosthetic disc designs (PDD): (1) PDD-I: The center of rotation of a spherical joint located at the mid C5-C6 disc, (2) PDD-II: The center of rotation of a spherical joint located 6.5 mm below the mid C5-C6 disc, and (3) PDD-III: The center of rotation of a spherical joint in a plane located at the C5-C6 disc level. A constrained spherical joint placed at the disc level (PDD-I) significantly increased facet loads during extension. Lowering the rotational axis of the spherical joint towards the subjacent body (PDD-II) caused a marginal increase in facet loading during flexion, extension, and lateral bending. Lastly, unconstraining the spherical joint to move freely in a plane (PDD-III) minimized facet load build up during all loading modes. The simulation model showed the impact simple design changes may have on cervical disc dynamics. The predicted facet loads calculated from computer model have to be validated in the experimental study.

Spinal cord stimulation modulates intraspinal colorectal visceroreceptive transmission in rats

PubMed Central

Qin, C.; Lehew, R.T.; Khan, K.A.; Wienecke, G.M.; Foreman, R.D.

2007-01-01

Previous studies have shown that spinal cord stimulation (SCS) of upper lumbar segments decreases visceromotor responses to mechanical stimuli in a sensitized rat colon and reduces symptoms of irritable bowel syndrome in patients. SCS applied to the upper cervical spinal dorsal column reduces pain of chronic refractory angina. Further, chemical stimulation of C1-C2 propriospinal neurons in rats modulates the responses of lumbosacral spinal neurons to colorectal distension. The present study was designed to compare the effects of upper cervical and lumbar SCS on activity of lumbosacral neurons receiving noxious colorectal input. Extracellular potentials of L6-S2 spinal neurons were recorded in pentobarbital anesthetized, paralyzed and ventilated male rats. SCS (50 Hz, 0.2 ms) at low intensity (90% of motor threshold) was applied to the dorsal column of upper cervical (C1-C2) or upper lumbar (L2-L3) ipsilateral spinal segments. Colorectal distension (CRD, 20, 40, 60 mmHg, 20 s) was produced by air inflation of a latex balloon. Results showed that SCS applied to L2-L3 and C1-C2 segments significantly reduced the excitatory responses to noxious CRD from 417.6±68.0 imp to 296.3±53.6 imp (P<0.05, n=24) and from 336.2±64.5 imp to 225.0±73.3 imp (P<0.05, n= 18), respectively. Effects of L2-L3 and C1-C2 SCS lasted 10.2±1.9 min and 8.0±0.9 min after offset of CRD. Effects of SCS were observed on spinal neurons with either high or low threshold excitatory responses to CRD. However, L2-L3 or C1-C2 SCS did not significantly affect inhibitory neuronal responses to CRD. C1-C2 SCS-induced effects were abolished by cutting the C7-C8 dorsal column but not by spinal transection at cervicomedullary junction. These data demonstrated that upper cervical or lumbar SCS modulated responses of lumbosacral spinal neurons to noxious mechanical stimulation of the colon, thereby, proved two loci for a potential therapeutic effect of SCS in patients with irritable bowel syndrome and other colonic disorders. PMID:17324482

Biomechanics of Artificial Disc Replacements Adjacent to a 2-Level Fusion in 4-Level Hybrid Constructs: An In Vitro Investigation

PubMed Central

Liao, Zhenhua; Fogel, Guy R.; Wei, Na; Gu, Hongsheng; Liu, Weiqiang

2015-01-01

Background The ideal procedure for multilevel cervical degenerative disc diseases remains controversial. Recent studies on hybrid surgery combining anterior cervical discectomy and fusion (ACDF) and artificial cervical disc replacement (ACDR) for 2-level and 3-level constructs have been reported in the literature. The purpose of this study was to estimate the biomechanics of 3 kinds of 4-level hybrid constructs, which are more likely to be used clinically compared to 4-level arthrodesis. Material/Methods Eighteen human cadaveric spines (C2–T1) were evaluated in different testing conditions: intact, with 3 kinds of 4-level hybrid constructs (hybrid C3–4 ACDR+C4–6 ACDF+C6–7ACDR; hybrid C3–5ACDF+C5–6ACDR+C6–7ACDR; hybrid C3–4ACDR+C4–5ACDR+C5–7ACDF); and 4-level fusion. Results Four-level fusion resulted in significant decrease in the C3–C7 ROM compared with the intact spine. The 3 different 4-level hybrid treatment groups caused only slight change at the instrumented levels compared to intact except for flexion. At the adjacent levels, 4-level fusion resulted in significant increase of contribution of both upper and lower adjacent levels. However, for the 3 hybrid constructs, significant changes of motion increase far lower than 4P at adjacent levels were only noted in partial loading conditions. No destabilizing effect or hypermobility were observed in any 4-level hybrid construct. Conclusions Four-level fusion significantly eliminated motion within the construct and increased motion at the adjacent segments. For all 3 different 4-level hybrid constructs, ACDR normalized motion of the index segment and adjacent segments with no significant hypermobility. Compared with the 4-level ACDF condition, the artificial discs in 4-level hybrid constructs had biomechanical advantages compared to fusion in normalizing adjacent level motion. PMID:26694835

Biomechanics of Artificial Disc Replacements Adjacent to a 2-Level Fusion in 4-Level Hybrid Constructs: An In Vitro Investigation.

PubMed

Liao, Zhenhua; Fogel, Guy R; Wei, Na; Gu, Hongsheng; Liu, Weiqiang

2015-12-23

BACKGROUND The ideal procedure for multilevel cervical degenerative disc diseases remains controversial. Recent studies on hybrid surgery combining anterior cervical discectomy and fusion (ACDF) and artificial cervical disc replacement (ACDR) for 2-level and 3-level constructs have been reported in the literature. The purpose of this study was to estimate the biomechanics of 3 kinds of 4-level hybrid constructs, which are more likely to be used clinically compared to 4-level arthrodesis. MATERIAL AND METHODS Eighteen human cadaveric spines (C2-T1) were evaluated in different testing conditions: intact, with 3 kinds of 4-level hybrid constructs (hybrid C3-4 ACDR+C4-6 ACDF+C6-7ACDR; hybrid C3-5ACDF+C5-6ACDR+C6-7ACDR; hybrid C3-4ACDR+C4-5ACDR+C5-7ACDF); and 4-level fusion. RESULTS Four-level fusion resulted in significant decrease in the C3-C7 ROM compared with the intact spine. The 3 different 4-level hybrid treatment groups caused only slight change at the instrumented levels compared to intact except for flexion. At the adjacent levels, 4-level fusion resulted in significant increase of contribution of both upper and lower adjacent levels. However, for the 3 hybrid constructs, significant changes of motion increase far lower than 4P at adjacent levels were only noted in partial loading conditions. No destabilizing effect or hypermobility were observed in any 4-level hybrid construct. CONCLUSIONS Four-level fusion significantly eliminated motion within the construct and increased motion at the adjacent segments. For all 3 different 4-level hybrid constructs, ACDR normalized motion of the index segment and adjacent segments with no significant hypermobility. Compared with the 4-level ACDF condition, the artificial discs in 4-level hybrid constructs had biomechanical advantages compared to fusion in normalizing adjacent level motion.

External stent for repair of secondary tracheomalacia.

PubMed

Johnston, M R; Loeber, N; Hillyer, P; Stephenson, L W; Edmunds, L H

1980-09-01

Tracheomalacia was created in anesthetized piglets by submucosal resection of 3 to 5 tracheal cartilages. Measurements of airway pressure and flow showed that expiratory airway resistance is maximal at low lung volumes and is significantly increased by creation of the malacic segment. Cervical flexion increases expiratory airway resistance, whereas hyperextension of the neck reduces resistance toward normal. External stenting of the malacic segment reduces expiratory airway resistance, and the combination of external stenting and hyperextension restores airway resistance to normal except at low lung volume. Two patients with secondary tracheomalacia required tracheostomy and could not be decannulated after the indication for the tracheostomy was corrected. Both were successfully decannulated after external stenting of the malacic segment with rib grafts. Postoperative measurements of expiratory pulmonary resistance show a marked decrease from preoperative measurements. External stenting of symptomatic tracheomalacia reduces expiratory airway resistance by supporting and stretching the malacic segment and is preferable to prolonged internal stenting or tracheal resection.

An Exploratory Study to Determine the Relationship between Cervical Dysfunction and Perimenstrual Migraines

PubMed Central

Horwitz, Simone

2015-01-01

ABSTRACT Purpose: To determine whether an association between cervical dysfunction and perimenstrual migraines exists. Methods: Forty perimenstrual migraine sufferers and 46 controls were compared. Information on the participants' ages and perceptions of neck pain and stiffness were solicited. The blinded physical examination of the cervical area consisted of postural, range of motion, muscle strength, muscle length, trigger point, neural mobility, and segmental cervical joint movement assessment. Results: The migraine group had increased perception of neck pain and stiffness (p<0.001); reduced bilateral rotation (p=0.013); decreased muscle length in both trapezii, left sternocleidomastoid, and right occipitals (p=0.045); more pain on muscle stretch in both levator scapulae, both trapezii, left sternocleidomastoid, and both occipitals (p=0.013); increased trigger points bilaterally in the left trapezius (p=0.021), right trapezius (p=0.023), left sternocleidomastoid (p=0.0.004), and right sternocleidomastoid (p=0.021); reduced neural mobility with bilateral elbow lag (p=0.043); greater C4–C6 pain (p=0.045); and increased cervical stiffness in C5–C7 (p=0.023). There were no differences in posture and muscle strength. Decreased muscle length increased the risk of perimenstrual migraines 2.4–6.7 fold, reduced neural mobility 5.8–10.7 fold, and increased C7 stiffness 17.0 fold. Conclusion: The results suggest that an association between cervical dysfunction and perimenstrual headaches should be further explored. PMID:25931651

γH2Ax Expression as a Potential Biomarker Differentiating between Low and High Grade Cervical Squamous Intraepithelial Lesions (SIL) and High Risk HPV Related SIL

PubMed Central

Kefala, Maria; Kottaridi, Christine; Spathis, Aris; Gouloumi, Alina-Roxani; Pouliakis, Abraham; Pappas, Asimakis; Sioulas, Vasileios; Chrelias, Charalambos; Karakitsos, Petros; Panayiotides, Ioannis

2017-01-01

Background γH2AX is a protein biomarker for double-stranded DNA breakage; its expression was studied in cervical squamous intraepithelial lesions and carcinomas. Methods Immunostaining for phospho-γH2AX was performed in sections from histologically confirmed cervical SIL and carcinomas, as well as from normal cervices used as controls. In total, 275 cases were included in the study: 112 low grade SIL (LGSIL), 99 high grade SIL (HGSIL), 24 squamous cell carcinoma (SCC), 12 adenocarcinoma and 28 cervical specimens with no essential lesions. Correlation of histological grading, high risk vs. low risk HPV virus presence, activated vs. non-activated status (by high risk HPV mRNA expression) and γH2AX expression in both basal and surface segments of the squamous epithelium was performed. Results Gradual increase of both basal and surface γH2AX expression was noted up from normal cervices to LGSIL harboring a low risk HPV type, to LGSIL harboring a high risk virus at a non-activated state (p<0.05). Thereafter, both basal and surface γH2AX expression dropped in LGSIL harboring a high risk virus at an activated state and in HGSIL. Conclusions γH2AX could serve as a potential biomarker discriminating between LGSIL and HGSIL, as well as between LGSIL harboring high risk HPV at an activated state. PMID:28118377

New technical tip for anterior cervical plating : make hole first and choose the proper plate size later.

PubMed

Park, Jeong Yoon; Zhang, Ho Yeol; Oh, Min Chul

2011-04-01

It is well known that plate-to-disc distance (PDD) is closely related to adjacent-level ossification following anterior cervical plate placement. The study was undertaken to compare the outcomes of two different anterior cervical plating methods for degenerative cervical condition. Specifically, the new method involves making holes for plate screws first with an air drill and then choosing a plate size. The other method was standard, that is, decide on the plate size first, locate the plate on the anterior vertebral body, and then drilling the screw holes. Our null hypothesis was that the new technical tip may increase PDD as compared with the standard anterior cervical plating procedure. We retrospectively reviewed 49 patients who had a solid fusion after anterior cervical arthrodesis with a plate for the treatment of cervical disc degeneration. Twenty-three patients underwent the new anterior cervical plating technique (Group A) and 26 patients underwent the standard technique (Group B). PDD and ratios between PDD to anterior body heights (ABH) were measured using postoperative lateral radiographs. In addition, operating times and clinical results were reviewed in all cases. The mean durations of follow-up were 16.42±5.99 (Group A) and 19.83±6.71 (Group B) months, range 12 to 35 months. Of these parameters mentioned above, cephalad PDD (5.43 versus 3.46 mm, p=0.005) and cephalad PDD/ABH (0.36 versus 0.23, p=0.004) were significantly greater in the Group A, whereas operation time for two segment arthrodesis (141.9 versus 170.6 minutes, p=0.047) was significantly lower in the Group A. There were no significant difference between the two groups in caudal PDD (5.92 versus 5.06 mm), caudal PDD/ABH (0.37 versus 0.32) and clinical results. The new anterior cervical plating method represents an improvement over the standard method in terms of cephalad plate-to-disc distance and operating time.

A Subcortical Oscillatory Network Contributes to Recovery of Hand Dexterity after Spinal Cord Injury

ERIC Educational Resources Information Center

Nishimura, Yukio; Morichika, Yosuke; Isa, Tadashi

2009-01-01

Recent studies have shown that after partial spinal-cord lesion at the mid-cervical segment, the remaining pathways compensate for restoring finger dexterity; however, how they control hand/arm muscles has remained unclear. To elucidate the changes in dynamic properties of neural circuits connecting the motor cortex and hand/arm muscles, we…

Segmentation of mosaicism in cervicographic images using support vector machines

NASA Astrophysics Data System (ADS)

Xue, Zhiyun; Long, L. Rodney; Antani, Sameer; Jeronimo, Jose; Thoma, George R.

2009-02-01

The National Library of Medicine (NLM), in collaboration with the National Cancer Institute (NCI), is creating a large digital repository of cervicographic images for the study of uterine cervix cancer prevention. One of the research goals is to automatically detect diagnostic bio-markers in these images. Reliable bio-marker segmentation in large biomedical image collections is a challenging task due to the large variation in image appearance. Methods described in this paper focus on segmenting mosaicism, which is an important vascular feature used to visually assess the degree of cervical intraepithelial neoplasia. The proposed approach uses support vector machines (SVM) trained on a ground truth dataset annotated by medical experts (which circumvents the need for vascular structure extraction). We have evaluated the performance of the proposed algorithm and experimentally demonstrated its feasibility.

Urinary Tract Resections in Advanced-stage Cervical Cancer - A Series of Eight Cases.

PubMed

Oprescu, Dana Nuti; Bacalbasa, Nicolae; Balescu, Irina; Filipescu, Alexandru

2017-06-01

Cervical cancer is one of the most frequent malignancies in women worldwide and is unfortunately diagnosed in advanced stages of the disease. Whenever local invasion is present, neoadjuvant therapy might be needed in order to limit the degree of local invasion. However, in certain cases local invasion persists even after completing the neoadjuvant radiochemotherapy; in these patients more extensive resections might be needed in order to achieve a radical resection. We present a case series of eight patients in whom segmental ureteral or uretero-vesical resections were performed as part of the radical resections for locally advanced cervical tumors. The continuity of the urinary tract was re-established by performing ureteral reimplantation via uretero-neocystostomy, augmentation cystoplasties with ureteral reimplantations. In a single case ureteral reimplantation was not feasible, a definitive cutaneous ureterostomy being performed. The postoperative course was uneventful in seven cases while in a single case urinary leak occurred, necessitating the exteriorization of the ureter in terminal cutaneous ureterostomy. Ureteral resections can be safely performed in patients with locally advanced cervical cancer. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Acute quadriplegia in a young man secondary to prothrombin G20210A mutation.

PubMed

Sawaya, R; Diken, Z; Mahfouz, R

2011-08-01

We present the case of an 18-year-old man, previously healthy, who presented with acute quadriplegia and respiratory failure. Physical examination was compatible with a high cervical anterior spinal cord lesion. We plan to evaluate the cause of such a neurological presentation in a healthy young man. American University Medical Center, Beirut, Lebanon. The patient underwent routine blood hematological and chemistry work-up, hypercoagulable profile studies, genetic profile for thrombophelias, radiographic studies of the brain and cervical cord, cerebrospinal analysis and extensive electrophyisological studies. Magnetic resonance imaging and magnetic resonance angiogram of the brain, carotid and intracranial vessels were normal. Cerebral angiography was normal. Magnetic resonance imaging of the cervical cord revealed lesion of the anterior segment of the cervical cord between C2 and C5 levels. Hypercoagulable profile studies were normal. Electrophysiological studies confirmed an isolated lesion of the descending cortico-spinal tracts. DNA analysis revealed the presence of a G20210A mutation-causing hyperprothrombinemia. We conclude that a G20210A mutation causing-hyperprothrombinemia can cause anterior spinal artery thrombosis and anterior spinal cord infarction with the resultant neurological deficits in otherwise healthy patients.

Comorbidity of internal derangement of the temporomandibular joint and silent dysfunction of the cervical spine.

PubMed

Stiesch-Scholz, M; Fink, M; Tschernitschek, H

2003-04-01

The aim of this evaluation was to examine correlations between internal derangement of the temporomandibular joint (TMJ) and cervical spine disorder (CSD). A prospective controlled clinical study was carried out. Thirty patients with signs and symptoms of internal derangement but without any subjective neck problems and 30 age- and gender-matched control subjects without signs and symptoms of internal derangement were examined. The investigation of the temporomandibular system was carried out using a 'Craniomandibular Index'. Afterwards an examiner-blinded manual medical investigation of the craniocervical system was performed. This included muscle palpation of the cervical spine and shoulder girdle as well as passive movement tests of the cervical spine, to detect restrictions in the range of movement as well as segmental intervertebral dysfunction. The internal derangement of the TMJ was significantly associated with 'silent' CSD (t-test, P < 0.05). Patients with raised muscle tenderness of the temporomandibular system exhibited significantly more often pain on pressure of the neck muscles than patients without muscle tenderness of the temporomandibular system (t-test, P < 0.05). As a result of the present study, for patients with internal derangement of the TMJ an additional examination of the craniocervical system should be recommended.

Clinical features and surgical procedures of congenital vaginal atresia-A retrospective study of 67 patients.

PubMed

Xie, Zhihong; Zhang, Xiaoping; Zhang, Ningzhi; Xiao, Hong; Liu, Yongying; Liu, Jiandong; Chen, Lili; Li, Liang; Zhang, Linlin; Zhang, Youguo

2017-10-01

To explore the characteristics of congenital vaginal atresia, further improve its classification, and therefore help the clinical diagnosis and treatment of congenital vaginal atresia. This was a retrospective study of 67 patients with congenital vaginal atresia (from March 1984 to March 2015). Clinical and surgical characteristics were analyzed. For lower vaginal atresia, 25 patients successfully underwent vaginoplasty at the lower portion of the vagina. For complete vagina atresia, 25 patients with type i cervical atresia were treated with artificial vaginoplasty+tracheloplasty, and all showed no dysmenorrhea within six months after surgery. Four patients with type ii cervical atresia and two patients with type iii cervical atresia successfully underwent hysterectomy+artificialvaginoplasty. Two patients with type iv cervical atresia underwent combined abdominoperineal artificial vaginoplasty+tracheloplasty. One patient with upper vaginal atresia successfully underwent hysterectomy via the narrow segment of the cervix. Three patients with top vaginal atresia had no dysmenorrhea after transvaginaltracheloplasty. This study suggests two new categories of vaginal atresia (upper vaginal atresia and top vaginal atresia), which could be used as a reference for treatment of this condition. Appropriate treatments were performed using a personalized approach and satisfactory results were achieved. Copyright © 2017. Published by Elsevier B.V.

Examining the Uppermost Surface of the Moon

NASA Technical Reports Server (NTRS)

Noble, Sarah K.

2010-01-01

Understanding the properties of the uppermost lunar surface is critical as it is the optical surface that is probed by remote-sensing data, like that which is and will be generated by instruments on orbiting missions (e.g. M3, LRO). The uppermost material is also the surface with which future lunar astronauts and their equipment will be in direct contact, and thus understanding its properties will be important for dust mitigation and toxicology issues. Furthermore, exploring the properties of this uppermost surface may provide insight into conditions at this crucial interface, such as grain charging and levitation

An Investigation of Fat Infiltration of the Multifidus Muscle in Patients With Severe Neck Symptoms Associated With Chronic Whiplash-Associated Disorder.

PubMed

Karlsson, Anette; Leinhard, Olof Dahlqvist; Åslund, Ulrika; West, Janne; Romu, Thobias; Smedby, Örjan; Zsigmond, Peter; Peolsson, Anneli

2016-10-01

Study Design Cross-sectional study. Background Findings of fat infiltration in cervical spine multifidus, as a sign of degenerative morphometric changes due to whiplash injury, need to be verified. Objectives To develop a method using water/fat magnetic resonance imaging (MRI) to investigate fat infiltration and cross-sectional area of multifidus muscle in individuals with whiplash-associated disorders (WADs) compared to healthy controls. Methods Fat infiltration and cross-sectional area in the multifidus muscles spanning the C4 to C7 segmental levels were investigated by manual segmentation using water/fat-separated MRI in 31 participants with WAD and 31 controls, matched for age and sex. Results Based on average values for data spanning C4 to C7, participants with severe disability related to WAD had 38% greater muscular fat infiltration compared to healthy controls (P = .03) and 45% greater fat infiltration compared to those with mild to moderate disability related to WAD (P = .02). There were no significant differences between those with mild to moderate disability and healthy controls. No significant differences between groups were found for multifidus cross-sectional area. Significant differences were observed for both cross-sectional area and fat infiltration between segmental levels. Conclusion Participants with severe disability after a whiplash injury had higher fat infiltration in the multifidus compared to controls and to those with mild/moderate disability secondary to WAD. Earlier reported findings using T1-weighted MRI were reproduced using refined imaging technology. The results of the study also indicate a risk when segmenting single cross-sectional slices, as both cross-sectional area and fat infiltration differ between cervical levels. J Orthop Sports Phys Ther 2016;46(10):886-893. Epub 2 Sep 2016. doi:10.2519/jospt.2016.6553.

Distribution of glycinergic neuronal somata in the rat spinal cord.

PubMed

Hossaini, Mehdi; French, Pim J; Holstege, Jan C

2007-04-20

Glycine transporter 2 (GlyT2) mRNA is exclusively expressed in glycinergic neurons, and is presently considered a reliable marker for glycinergic neuronal somata. In this study, we have performed non-radioactive in situ hybridization to localize GlyT2 mRNA in fixed free-floating sections of cervical (C2 and C6), thoracic (T5), lumbar (L2 and L5) and sacral (S1) segments of the rat spinal cord. The results showed that in all segments the majority of the GlyT2 mRNA labeled (glycinergic) neuronal somata was present in the deep dorsal horn and the intermediate zone (laminae III-VIII), with around 50% (range 43.7-70.9%) in laminae VII&VIII. In contrast, the superficial dorsal horn, the motoneuronal cell groups and the area around the central canal contained only few glycinergic neuronal somata. The density (number of glycinergic neuronal somata per mm(2)) was also low in these areas, while the highest densities were found in laminae V to VIII. The lateral spinal nucleus and the lateral cervical nucleus also contained a limited number of glycinergic neurons. Our findings showed that the distribution pattern of the glycinergic neuronal somata is similar in all the examined segments. The few differences that were found in the relative laminar distribution between some of the segments, are most likely due to technical reasons. We therefore conclude that the observed distribution pattern of glycinergic neuronal somata is present throughout the spinal cord. Our findings further showed that the non-radioactive in situ hybridization technique for identifying GlyT2 mRNA in fixed free-floating sections is a highly efficient tool for identifying glycinergic neurons in the spinal cord.

Outcome of physiotherapy after surgery for cervical disc disease: a prospective randomised multi-centre trial

PubMed Central

2014-01-01

Background Many patients with cervical disc disease require leave from work, due to long-lasting, complex symptoms, including chronic pain and reduced levels of physical and psychological function. Surgery on a few segmental levels might be expected to resolve disc-specific pain and reduce neurological deficits, but not the non-specific neck pain and the frequent illness. No study has investigated whether post-surgery physiotherapy might improve the outcome of surgery. The main purpose of this study was to evaluate whether a well-structured rehabilitation programme might add benefit to the customary post-surgical treatment for cervical disc disease, with respect to function, disability, work capability, and cost effectiveness. Methods/Design This study was designed as a prospective, randomised, controlled, multi-centre study. An independent, blinded investigator will compare two alternatives of rehabilitation. We will include 200 patients of working age, with cervical disc disease confirmed by clinical findings and symptoms of cervical nerve root compression. After providing informed consent, study participants will be randomised to one of two alternative physiotherapy regimes; (A) customary treatment (information and advice on a specialist clinic); or (B) customary treatment plus active physiotherapy. Physiotherapy will follow a standardised, structured programme of neck-specific exercises combined with a behavioural approach. All patients will be evaluated both clinically and subjectively (with questionnaires) before surgery and at 6 weeks, 3 months, 6 months, 12 months, and 24 months after surgery. The main outcome variable will be neck-specific disability. Cost-effectiveness will also be calculated. Discussion We anticipate that the results of this study will provide evidence to support physiotherapeutic rehabilitation applied after surgery for cervical radiculopathy due to cervical disc disease. Trial registration ClinicalTrials.gov identifier: NCT01547611 PMID:24502414

Development of a finite element model of the ligamentous cervical vertebral column of a Great Dane.

PubMed

Bonelli, Marília de Albuquerque; Shah, Anoli; Goel, Vijay; Costa, Fabiano Séllos; da Costa, Ronaldo Casimiro

2018-06-01

Cervical spondylomyelopathy (CSM), also known as wobbler syndrome, affects mainly large and giant-breed dogs, causing compression of the cervical spinal cord and/or nerve roots. Structural and dynamic components seem to play a role in the development of CSM; however, pathogenesis is not yet fully understood. Finite element models have been used for years in human medicine to study the dynamic behavior of structures, but it has been mostly overlooked in veterinary studies. To our knowledge, no specific ligamentous spine models have been developed to investigate naturally occurring canine myelopathies and possible surgical treatments. The goal of this study was to develop a finite element model (FEM) of the C 2 -C 7 segment of the ligamentous cervical vertebral column of a neurologically normal Great Dane without imaging changes. The FEM of the intact C 2 -C 7 cervical vertebral column had a total of 188,906 elements (175,715 tetra elements and 12,740 hexa elements). The range of motion (in degrees) for the FEM subjected to a moment of 2Nm was approximately 27.94 in flexion, 25.86 in extension, 24.14 in left lateral bending, 25.27 in right lateral bending, 17.44 in left axial rotation, and 16.72 in right axial rotation. We constructed a ligamentous FEM of the C 2 -C 7 vertebral column of a Great Dane dog, which can serve as a platform to be modified and adapted for studies related to biomechanics of the cervical vertebral column and to further improve studies on osseous-associated cervical spondylomyelopathy. Copyright © 2018 Elsevier Ltd. All rights reserved.

Anterior cervical pedicle screw and plate fixation using fluoroscope-assisted pedicle axis view imaging: a preliminary report of a new cervical reconstruction technique

PubMed Central

Kato, Fumihiko; Ito, Keigo; Nakashima, Hiroaki; Machino, Masaaki

2009-01-01

Anterior procedures in the cervical spine are feasible in cases having anterior aetiologies such as anterior neural compression and/or severe kyphosis. Halo vests or anterior plates are used concurrently for cases with long segmental fixation. Halo vests are bothersome and anterior plate fixation is not adequately durable. We developed a new anterior pedicle screw (APS) and plate fixation procedure that can be used with fluoroscope-assisted pedicle axis view imaging. Six patients (3 men and 3 women; mean age, 54 years) with anterior multisegmental aetiology were included in this study. Their original diagnoses comprised cervical myelopathy and/or radiculopathy (n = 4), posterior longitudinal ligament ossification (n = 1) and post-traumatic kyphosis (n = 1). All patients underwent anterior decompression and strut grafting with APS and plate fixation. Mean operative time was 192 min and average blood loss was 73 ml. Patients were permitted to ambulate the next day with a cervical collar. Local sagittal alignment was characterised by 3.5° of kyphosis preoperatively, which improved to 6.8° of lordosis postoperatively and 5.2° of lordosis at final follow-up. Postoperative improvement and early bony union were observed in all cases. There was no serious complication except for two cases of dysphagia. Postoperative imaging demonstrated screw exposure in one screw, but no pedicle perforation. APS and plate fixation is useful in selected cases of multisegmental anterior reconstruction of cervical spine. However, the adequate familiarity and experience with both cervical pedicle screw fixation and the imaging technique used for visualising the pedicle during surgery are crucial for this procedure. PMID:19343377

Assessment of cervical spine movement during laryngoscopy with Macintosh and Truview laryngoscopes

PubMed Central

Bhardwaj, Neerja; Jain, Kajal; Rao, Madhusudan; Mandal, Arup Kumar

2013-01-01

Background: Truview laryngoscope provides an indirect view of the glottis and will cause less cervical spine movement since a ventral lifting force will not be required to visualize the glottis compared to Macintosh laryngoscope. Materials and Methods: A randomized crossover study to assess the degree of movement of cervical spine during endotracheal intubation with Truview laryngoscope was conducted in 25 adult ASA-I patients. After a standard anesthetic technique laryngoscopy was performed twice in each patient using in turn both the Macintosh and Truview laryngoscopes. A baseline radiograph with the head and neck in a neutral position was followed by a second radiograph taken during each laryngoscopy. An experienced radiologist analyzed and measured the cervical movement. Results: Significant cervical spine movement occurred at all segments when compared to the baseline with both the Macintosh and Truview laryngoscopes (P < 0.001). However, the movement was significantly less with Truview compared to the Macintosh laryngoscope at C0–C1 (21%; P = 0.005) and C1–C2 levels (32%; P = 0.009). The atlantooccipital distance (AOD) traversed while using Truview laryngoscope was significantly less than with Macintosh blade (26%; P = 0.001). Truview blade produced a better laryngoscopic view (P = 0.005) than Macintosh blade, but had a longer time to laryngoscopy (P = 0.04). Conclusion: Truview laryngoscope produced a better laryngoscopic view of glottis as compared with Macintosh laryngoscopy. It also produced significantly less cervical spine movement at C0–C1 and C1–C2 levels than with Macintosh laryngoscope in patients without cervical spine injury and without manual in-line stabilization (MILS). Further studies are warranted with Truview laryngoscope using MILS. PMID:24106352

Intubation Biomechanics: Laryngoscope Force and Cervical Spine Motion during Intubation in Cadavers—Cadavers vs. Patients, the Effect of Repeated Intubations, and the Effect of Type II Odontoid Fracture on C1-C2 Motion

PubMed Central

Hindman, Bradley J.; From, Robert P.; Fontes, Ricardo B.; Traynelis, Vincent C.; Todd, Michael M.; Zimmerman, M. Bridget; Puttlitz, Christian M.; Santoni, Brandon G.

2015-01-01

Introduction The aims of this study were to characterize: 1) cadaver intubation biomechanics, including the effect of repeated intubations; and 2) the relationship between intubation force and the motion of an injured cervical segment. Methods Fourteen cadavers were serially intubated using force-sensing Macintosh and Airtraq laryngoscopes in random order, with simultaneous cervical spine motion recorded with lateral fluoroscopy. Motion of the C1-C2 segment was measured in the intact and injured state (Type II odontoid fracture). Injured C1-C2 motion was proportionately corrected for changes in intubation forces that occurred with repeated intubations. Results Cadaver intubation biomechanics were comparable to those of patients in all parameters other than C2-C5 extension. In cadavers, intubation force (Set 2/Set1 force ratio = 0.61 [95% CI: 0.46, 0.81]; P=0.002) and Oc-C5 extension (Set 2 –Set 1 difference = −6.1 degrees [95% CI: −11.4, −0.9]; P=0.025) decreased with repeated intubations. In cadavers, C1-C2 extension did not differ: 1) between intact and injured states; or 2) in the injured state, between laryngoscopes (with and without force correction). With force correction, in the injured state, C1-C2 subluxation was greater with the Airtraq (mean difference 2.8 mm [95% CI: 0.7, 4.9 mm]; P=0.004). Discussion With limitations, cadavers may be clinically relevant models of intubation biomechanics and cervical spine motion. In the setting of a Type II odontoid fracture, C1-C2 motion during intubation with either the Macintosh or Airtraq does not appear to greatly exceed physiologic values or to have a high likelihood of hyperextension or direct cord compression. PMID:26288267

Clinical and radiological analysis of Bryan cervical disc arthroplasty: eight-year follow-up results compared with anterior cervical discectomy and fusion.

PubMed

Lei, Tao; Liu, Yaming; Wang, Hui; Xu, Jiaxin; Ma, Qinghua; Wang, Linfeng; Shen, Yong

2016-06-01

Bryan cervical disc arthroplasty has been reported with satisfactory short- and medium-term clinical results. However, the long-term clinical and radiographic outcomes are seldom reported. The purpose of this study was to compare the eight-year follow-up results in patients who underwent Bryan disc arthroplasty with patients received ACDF, and assess the incidence of heterotopic ossification (HO) and its effect on clinical outcome and mobility of the device. Thirty-one patients underwent Bryan disc arthroplasty, and 35 patients underwent ACDF were included in the study. The Japanese Orthopedic Association (JOA) scores, neck disability index (NDI), visual analogue scale (VAS) of neck and arm pain, and the radiographs were used to evaluate the outcomes. The heterotopic ossification (HO) was determined by CT scan and was classified into three subgroups to compare the related effect. Adjacent segment degeneration (ASD) was also observed. At final follow-up, there were no significant differences in JOA scores between two groups, but the improvement in NDI and neck or arm VAS were significantly greater in the Bryan disc cohort. The range of motion at the index level was 7.0° in Bryan group, while 100 % bone fusion were achieved in ACDF group. HO was observed in 18 (51.4 %) levels. There were more restricted movement of the prosthesis and slight higher rate of axial pain in patients with severe-HO (grade III and IV). Fourteen (28.6 %) levels developed ASD in Bryan group, which was significantly lower than that (58.6 %) in ACDF group. At eight year follow-up, the clinical and radiographic outcomes of Bryan cervical disc arthroplasty compared favorably to those of ACDF. It avoided accelerated adjacent segment degeneration by preserving motion. However, severe HO restricted the ROM of the index levels and maybe associated with post-operative axial pain.

The Effect of Ambient Titanium Dioxide Microparticle Exposure to the Ocular Surface on the Expression of Inflammatory Cytokines in the Eye and Cervical Lymph Nodes.

PubMed

Eom, Youngsub; Song, Jong Suk; Lee, Hyun Kyu; Kang, Boram; Kim, Hyeon Chang; Lee, Hyung Keun; Kim, Hyo Myung

2016-12-01

To investigate the ocular immune response following exposure to airborne titanium dioxide (TiO2) microparticles. Rats in the TiO2-exposed group (n = 10) were exposed to TiO2 particles for 2 hours twice daily for 5 days, while the controls (n = 10) were not. Corneal staining score and tear lactic dehydrogenase (LDH) activity were measured to evaluate ocular surface damage, serum immunoglobulin (Ig) G and E were assayed by using enzyme-linked immunosorbent assay, and the size of cervical lymph nodes was measured. In addition, the expression of interleukin (IL)-4, IL-17, and interferon (IFN)-γ in the anterior segment of the eyeball and cervical lymph nodes was measured by immunohistochemistry, real-time reverse transcription-polymerase chain reaction (RT-PCR), and Western blot analysis. Median corneal staining score (3.0), tear LDH activity (0.24 optical density [OD]), and cervical lymph node size (36.9 mm2) were significantly higher in the TiO2-exposed group than in the control group (1.0, 0.13 OD, and 26.7 mm2, respectively). Serum IgG and IgE levels were found to be significantly elevated in the TiO2-exposed group (P = 0.021 and P = 0.021, respectively). Interleukin 4 expression was increased in the anterior segment of the eyeball and lymph nodes following TiO2 exposure, as measured by immunostaining, real-time RT-PCR, and Western blot. In addition, IL-17 and IFN-γ levels were also increased following TiO2 exposure compared to controls as measured by immunostaining. Exposure to airborne TiO2 induced ocular surface damage. The Type 2 helper T-cell pathway seems to play a dominant role in the ocular immune response following airborne TiO2 exposure.

Reoperation After Cervical Disc Arthroplasty Versus Anterior Cervical Discectomy and Fusion: A Meta-analysis.

PubMed

Zhong, Zhao-Ming; Zhu, Shi-Yuan; Zhuang, Jing-Shen; Wu, Qian; Chen, Jian-Ting

2016-05-01

Anterior cervical discectomy and fusion is a standard surgical treatment for cervical radiculopathy and myelopathy, but reoperations sometimes are performed to treat complications of fusion such as pseudarthrosis and adjacent-segment degeneration. A cervical disc arthroplasty is designed to preserve motion and avoid the shortcomings of fusion. Available evidence suggests that a cervical disc arthroplasty can provide pain relief and functional improvements similar or superior to an anterior cervical discectomy and fusion. However, there is controversy regarding whether a cervical disc arthroplasty can reduce the frequency of reoperations. We performed a meta-analysis of randomized controlled trials (RCTs) to compare cervical disc arthroplasty with anterior cervical discectomy and fusion regarding (1) the overall frequency of reoperation at the index and adjacent levels; (2) the frequency of reoperation at the index level; and (3) the frequency of reoperation at the adjacent levels. PubMed, EMBASE, and the Cochrane Register of Controlled Trials databases were searched to identify RCTs comparing cervical disc arthroplasty with anterior cervical discectomy and fusion and reporting the frequency of reoperation. We also manually searched the reference lists of articles and reviews for possible relevant studies. Twelve RCTs with a total of 3234 randomized patients were included. Eight types of disc prostheses were used in the included studies. In the anterior cervical discectomy and fusion group, autograft was used in one study and allograft in 11 studies. Nine of 12 studies were industry sponsored. Pooled risk ratio (RR) and associated 95% CI were calculated for the frequency of reoperation using random-effects or fixed-effects models depending on the heterogeneity of the included studies. A funnel plot suggested the possible presence of publication bias in the available pool of studies; that is, the shape of the plot suggests that smaller negative or no-difference studies may have been performed but have not been published, and so were not identified and included in this meta-analysis. The overall frequency of reoperation at the index and adjacent levels was lower in the cervical disc arthroplasty group (6%; 108/1762) than in the anterior cervical discectomy and fusion group (12%; 171/1472) (RR, 0.54; 95% CI, 0.36-0.80; p = 0.002). Subgroup analyses were performed according to secondary surgical level. Compared with anterior cervical discectomy and fusion, cervical disc arthroplasty was associated with fewer reoperations at the index level (RR, 0.50; 95% CI, 0.37-0.68; p < 0.001) and adjacent levels (RR, 0.52; 95% CI, 0.37-0.74; p < 0.001). Cervical disc arthroplasty is associated with fewer reoperations than anterior cervical discectomy and fusion, indicating that it is a safe and effective alternative to fusion for cervical radiculopathy and myelopathy. However, because of some limitations, these findings should be interpreted with caution. Additional studies are needed. Level I, therapeutic study.

Clinical and radiographic analysis of an artificial cervical disc: 7-year follow-up from the Prestige prospective randomized controlled clinical trial: Clinical article.

PubMed

Burkus, J Kenneth; Traynelis, Vincent C; Haid, Regis W; Mummaneni, Praveen V

2014-10-01

The authors assess the long-term safety and efficacy of cervical disc replacement with the Prestige Cervical Disc in a prospective, randomized, multicenter trial at 7 years of follow-up. At 31 investigational sites, 541 patients with single-level cervical disc disease with radiculopathy were randomized to 1 of 2 treatment groups: 276 investigational group patients underwent anterior cervical discectomy and arthroplasty with the Prestige disc, and 265 control group patients underwent anterior cervical discectomy and fusion. Clinical outcomes included Neck Disability Index, the 36-Item Short-Form Health Survey, and neck and arm pain scores. Radiographs were assessed for angle of motion and fusion. Clinical and radiographic outcomes were evaluated preoperatively, intraoperatively, and at 1.5, 3, 6, 12, 24, 36, 60, and 84 months. Of the 541 patients treated, 395 patients (73%; 212 investigational and 183 control patients) completed 7 years of clinical follow-up. Significant improvements achieved by 1.5 months in both groups were sustained at 7 years. In the investigational group, mean Neck Disability Index improvements from preoperative scores were 38.2 and 37.5 at 60 and 84 months, respectively. In the control group, the corresponding means were 33.8 and 31.9. The differences between the investigational and control groups at the 60-month and 84-month periods were significant (p = 0.014 and 0.002, respectively). The overall rates of maintenance or improvement in neurological status in the investigational group were significantly higher: 92.2% and 88.2% at 60 months and 84 months, respectively, compared with 85.7% and 79.7% in the control group (p = 0.017 and 0.011, respectively). At 84 months, the percentage of working patients in the investigational group was 73.9%, and in the control group, 73.1%. Postoperatively, the implant effectively maintained average angular motion of 6.67° at 60 months and 6.75° at 84 months. Cumulative rates for surgery at the index level were lower (p < 0.001) in the investigational group (11 [4.8%] of 276) when compared with the control group (29 [13.7%] of 265) (based on life-table method), and there were statistical differences between the investigational and control groups with specific regard to the rate of subsequent revision and supplemental fixation surgical procedures. Rates for additional surgical procedures that involved adjacent levels were lower in the investigational group than in the control group (11 [4.6%] of 276 vs. 24 [11.9%] of 265, respectively). Cervical disc arthroplasty has the potential for preserving motion at the operated level while providing biomechanical stability and global neck mobility and may result in a reduction in adjacent-segment degeneration. The Prestige Cervical Disc maintains improved clinical outcomes and segmental motion after implantation at 7-year follow-up. Clinical trial registration no. NCT00642876 ( ClinicalTrials.gov ).

Correlation of cervical endplate strength with CT measured subchondral bone density

PubMed Central

Ordway, Nathaniel R.; Lu, Yen-Mou; Zhang, Xingkai; Cheng, Chin-Chang; Fang, Huang

2007-01-01

Cervical interbody device subsidence can result in screw breakage, plate dislodgement, and/or kyphosis. Preoperative bone density measurement may be helpful in predicting the complications associated with anterior cervical surgery. This is especially important when a motion preserving device is implanted given the detrimental effect of subsidence on the postoperative segmental motion following disc replacement. To evaluate the structural properties of the cervical endplate and examine the correlation with CT measured trabecular bone density. Eight fresh human cadaver cervical spines (C2–T1) were CT scanned and the average trabecular bone densities of the vertebral bodies (C3–C7) were measured. Each endplate surface was biomechanically tested for regional yield load and stiffness using an indentation test method. Overall average density of the cervical vertebral body trabecular bone was 270 ± 74 mg/cm3. There was no significant difference between levels. The yield load and stiffness from the indentation test of the endplate averaged 139 ± 99 N and 156 ± 52 N/mm across all cervical levels, endplate surfaces, and regional locations. The posterior aspect of the endplate had significantly higher yield load and stiffness in comparison to the anterior aspect and the lateral aspect had significantly higher yield load in comparison to the midline aspect. There was a significant correlation between the average yield load and stiffness of the cervical endplate and the trabecular bone density on regression analysis. Although there are significant regional variations in the endplate structural properties, the average of the endplate yield loads and stiffnesses correlated with the trabecular bone density. Given the morbidity associated with subsidence of interbody devices, a reliable and predictive method of measuring endplate strength in the cervical spine is required. Bone density measures may be used preoperatively to assist in the prediction of the strength of the vertebral endplate. A threshold density measure has yet to be established where the probability of endplate fracture outweighs the benefit of anterior cervical procedure. PMID:17712574

Comparative Study Between M6-C and Mobi-C Cervical Artificial Disc Replacement: Biomechanical Outcomes and Comparison with Normative Data.

PubMed

Pham, My; Phan, Kevin; Teng, Ian; Mobbs, Ralph J

2018-05-01

Cervical spondylosis affects a huge proportion of the middle-aged population. Degenerative changes can occur in multiple regions of the cervical spine typically affecting the joints, intervertebral discs and endplates. These changes lead to compression of adjacent nervous structures, which results in radiculopathic and myelopathic pain. Various treatment modalities are currently available with non-surgical approaches the initial go to if there is no symptomatic cord compression. Anterior cervical discectomy and fusion, or arthroplasty are the two common surgical approaches if non-surgical treatments fail to relieve symptoms of the patients or there are signs of central cord compression. However, studies have shown that there is an increased risk of adjacent segment disease related to fusion. Cervical disc arthroplasty aims to restore normal range of motion (ROM) in patients with pain and disability due to degenerative disc disease resistant to conservative care. Two common disc prostheses used include M6-C and Mobi-C. Both prostheses comprise a mobile polymer segment sandwiched between two metal endplates with mechanisms resembling an actual intervertebral disc. This study aims to compare the kinematics associated with these prostheses, against the normal range of motion in the non-degenerative population. Patients who underwent M6-C or Mobi-C disc replacements by the senior author from 2012 to 2015 were identified at a single tertiary institution. Routine 3-month postoperative lateral radiographs were analyzed for flexion and extension ROM angles at the involved vertebral level by two independent authors. Data was compared to previous published studies investigating cervical spine ROM of asymptomatic patients. There was no statistical significance in the difference of overall flexion range between M6-C and Mobi-C prostheses. However, overall range of extension of Mobi-C was greater compared to M6-C (P = 0.028). At C 5-6 , the range of flexion for both implants were similar but lesser compared to asymptomatic patients (P < 0.001). Range of extension was greater in the Mobi-C group (14.2° ± 5.1°) compared to the M6-C (7.3° ± 4.6°) (P = 0.0009). At C 6-7 , there were no statistical differences in both range of flexion and extension between the two prostheses and asymptomatic patients (P > 0.05). The early results regarding restoration of ROM following cervical arthroplasty using either M6-C or Mobi-C prosthesis are encouraging. Long-term follow-up studies are necessary to observe the change in ROM over time with physiological loading and wear patterns. © 2018 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

A statistical shape model of the human second cervical vertebra.

PubMed

Clogenson, Marine; Duff, John M; Luethi, Marcel; Levivier, Marc; Meuli, Reto; Baur, Charles; Henein, Simon

2015-07-01

Statistical shape and appearance models play an important role in reducing the segmentation processing time of a vertebra and in improving results for 3D model development. Here, we describe the different steps in generating a statistical shape model (SSM) of the second cervical vertebra (C2) and provide the shape model for general use by the scientific community. The main difficulties in its construction are the morphological complexity of the C2 and its variability in the population. The input dataset is composed of manually segmented anonymized patient computerized tomography (CT) scans. The alignment of the different datasets is done with the procrustes alignment on surface models, and then, the registration is cast as a model-fitting problem using a Gaussian process. A principal component analysis (PCA)-based model is generated which includes the variability of the C2. The SSM was generated using 92 CT scans. The resulting SSM was evaluated for specificity, compactness and generalization ability. The SSM of the C2 is freely available to the scientific community in Slicer (an open source software for image analysis and scientific visualization) with a module created to visualize the SSM using Statismo, a framework for statistical shape modeling. The SSM of the vertebra allows the shape variability of the C2 to be represented. Moreover, the SSM will enable semi-automatic segmentation and 3D model generation of the vertebra, which would greatly benefit surgery planning.

High-resolution nerve ultrasound and magnetic resonance neurography as complementary neuroimaging tools for chronic inflammatory demyelinating polyneuropathy

PubMed Central

Pitarokoili, Kalliopi; Kronlage, Moritz; Bäumer, Philip; Schwarz, Daniel; Gold, Ralf; Bendszus, Martin; Yoon, Min-Suk

2018-01-01

Background: We present a clinical, electrophysiological, sonographical and magnetic resonance neurography (MRN) study examining the complementary role of two neuroimaging methods of the peripheral nervous system for patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Furthermore, we explore the significance of cross-sectional area (CSA) increase through correlations with MRN markers of nerve integrity. Methods: A total of 108 nerve segments on the median, ulnar, radial, tibial and fibular nerve, as well as the lumbar and cervical plexus of 18 CIDP patients were examined with high-resonance nerve ultrasound (HRUS) and MRN additionally to the nerve conduction studies. Results: We observed a fair degree of correlation of the CSA values for all nerves/nerve segments between the two methods, with a low random error in Bland–Altman analysis (bias = HRUS-CSA − MRN-CSA, −0.61 to −3.26 mm). CSA in HRUS correlated with the nerve T2-weighted (nT2) signal increase as well as with diffusion tensor imaging parameters such as fractional anisotropy, a marker of microstructural integrity. HRUS-CSA of the interscalene brachial plexus correlated significantly with the MRN-CSA and nT2 signal of the L5 and S1 roots of the lumbar plexus. Conclusions: HRUS allows for reliable CSA imaging of all peripheral nerves and the cervical plexus, and CSA correlates with markers of nerve integrity. Imaging of proximal segments as well as the estimation of nerve integrity require MRN as a complementary method. PMID:29552093

Dynamic Motor Compensations with Permanent, Focal Loss of Forelimb Force after Cervical Spinal Cord Injury

PubMed Central

López-Dolado, Elisa; Lucas-Osma, Ana M.

2013-01-01

Abstract Incomplete cervical lesion is the most common type of human spinal cord injury (SCI) and causes permanent paresis of arm muscles, a phenomenon still incompletely understood in physiopathological and neuroanatomical terms. We performed spinal cord hemisection in adult rats at the caudal part of the segment C6, just rostral to the bulk of triceps brachii motoneurons, and analyzed the forces and kinematics of locomotion up to 4 months postlesion to determine the nature of motor function loss and recovery. A dramatic (50%), immediate and permanent loss of extensor force occurred in the forelimb but not in the hind limb of the injured side, accompanied by elbow and wrist kinematic impairments and early adaptations of whole-body movements that initially compensated the balance but changed continuously over the follow-up period to allow effective locomotion. Overuse of both contralateral legs and ipsilateral hind leg was evidenced since 5 days postlesion. Ipsilateral foreleg deficits resulted mainly from interruption of axons that innervate the spinal cord segments caudal to the lesion, because chronic loss (about 35%) of synapses was detected at C7 while only 14% of triceps braquii motoneurons died, as assessed by synaptophysin immunohistochemistry and retrograde neural tracing, respectively. We also found a large pool of propriospinal neurons projecting from C2–C5 to C7 in normal rats, with topographical features similar to the propriospinal premotoneuronal system of cats and primates. Thus, concurrent axotomy at C6 of brain descending axons and cervical propriospinal axons likely hampered spontaneous recovery of the focal neurological impairments. PMID:23249275

Ranges of Cervical Intervertebral Disc Deformation During an In Vivo Dynamic Flexion–Extension of the Neck

PubMed Central

Yu, Yan; Mao, Haiqing; Li, Jing-Sheng; Tsai, Tsung-Yuan; Cheng, Liming; Wood, Kirkham B.; Li, Guoan; Cha, Thomas D.

2017-01-01

While abnormal loading is widely believed to cause cervical spine disc diseases, in vivo cervical disc deformation during dynamic neck motion has not been well delineated. This study investigated the range of cervical disc deformation during an in vivo functional flexion–extension of the neck. Ten asymptomatic human subjects were tested using a combined dual fluoroscopic imaging system (DFIS) and magnetic resonance imaging (MRI)-based three-dimensional (3D) modeling technique. Overall disc deformation was determined using the changes of the space geometry between upper and lower endplates of each intervertebral segment (C3/4, C4/5, C5/6, and C6/7). Five points (anterior, center, posterior, left, and right) of each disc were analyzed to examine the disc deformation distributions. The data indicated that between the functional maximum flexion and extension of the neck, the anterior points of the discs experienced large changes of distraction/compression deformation and shear deformation. The higher level discs experienced higher ranges of disc deformation. No significant difference was found in deformation ranges at posterior points of all the discs. The data indicated that the range of disc deformation is disc level dependent and the anterior region experienced larger changes of deformation than the center and posterior regions, except for the C6/7 disc. The data obtained from this study could serve as baseline knowledge for the understanding of the cervical spine disc biomechanics and for investigation of the biomechanical etiology of disc diseases. These data could also provide insights for development of motion preservation surgeries for cervical spine. PMID:28334358

Ranges of Cervical Intervertebral Disc Deformation During an In Vivo Dynamic Flexion-Extension of the Neck.

PubMed

Yu, Yan; Mao, Haiqing; Li, Jing-Sheng; Tsai, Tsung-Yuan; Cheng, Liming; Wood, Kirkham B; Li, Guoan; Cha, Thomas D

2017-06-01

While abnormal loading is widely believed to cause cervical spine disc diseases, in vivo cervical disc deformation during dynamic neck motion has not been well delineated. This study investigated the range of cervical disc deformation during an in vivo functional flexion-extension of the neck. Ten asymptomatic human subjects were tested using a combined dual fluoroscopic imaging system (DFIS) and magnetic resonance imaging (MRI)-based three-dimensional (3D) modeling technique. Overall disc deformation was determined using the changes of the space geometry between upper and lower endplates of each intervertebral segment (C3/4, C4/5, C5/6, and C6/7). Five points (anterior, center, posterior, left, and right) of each disc were analyzed to examine the disc deformation distributions. The data indicated that between the functional maximum flexion and extension of the neck, the anterior points of the discs experienced large changes of distraction/compression deformation and shear deformation. The higher level discs experienced higher ranges of disc deformation. No significant difference was found in deformation ranges at posterior points of all the discs. The data indicated that the range of disc deformation is disc level dependent and the anterior region experienced larger changes of deformation than the center and posterior regions, except for the C6/7 disc. The data obtained from this study could serve as baseline knowledge for the understanding of the cervical spine disc biomechanics and for investigation of the biomechanical etiology of disc diseases. These data could also provide insights for development of motion preservation surgeries for cervical spine.

The Cervical Spinal Canal Tapers Differently in Patients with Chiari I with and without Syringomyelia.

PubMed

Thompson, A; Madan, N; Hesselink, J R; Weinstein, G; Munoz del Rio, A; Haughton, V

2016-04-01

The cause of syringomyelia in patients with Chiari I remains uncertain. Cervical spine anatomy modifies CSF velocities, flow patterns, and pressure gradients, which may affect the spinal cord. We tested the hypothesis that cervical spinal anatomy differs between Chiari I patients with and without syringomyelia. We identified consecutive patients with Chiari I at 3 institutions and divided them into groups with and without syringomyelia. Five readers measured anteroposterior cervical spinal diameters, tonsillar herniation, and syrinx dimensions on cervical MR images. Taper ratios for C1-C7, C1-C4, and C4-C7 spinal segments were calculated by linear least squares fitting to the appropriate spinal canal diameters. Mean taper ratios and tonsillar herniation for groups were compared and tested for statistical significance with a Kruskal-Wallis test. Inter- and intrareader agreement and correlations in the data were measured. One hundred fifty patients were included, of which 49 had syringomyelia. C1-C7 taper ratios were smaller and C4-C7 taper ratios greater for patients with syringomyelia than for those without it. C1-C4 taper ratios did not differ significantly between groups. Patients with syringomyelia had, on average, greater tonsillar herniation than those without a syrinx. However, C4-C7 taper ratios were steeper, for all degrees of tonsil herniation, in patients with syringomyelia. Differences among readers did not exceed differences among patient groups. The tapering of the lower cervical spine may contribute to the development of syringomyelia in patients with Chiari I. © 2016 by American Journal of Neuroradiology.

Multiple cervical hemivertebra resection and staged thoracic pedicle subtraction osteotomy in the treatment of complicated congenital scoliosis.

PubMed

Zhuang, Qianyu; Zhang, Jianguo; Wang, Shengru; Guo, Jianwei; Qiu, Guixing

2016-05-01

To present our experience of staged correction with multiple cervical hemivertebra resection and thoracic pedicle subtraction osteotomy (PSO) treating a rare and complicated congenital scoliosis. A 14-year-old male presented with progressive torticollis and spine deformity. The malformation developed since birth, and back pain after long-time sitting or exercise arose since 6 months before, which was unsuccessfully treated by physiotherapy. X-ray showed a right cervical curve of 60° and a left compensatory thoracic curve of 90°. Three-dimensional computed tomography (3-D CT) scan revealed three semi-segmented hemivertebrae (C4, C5 and C6) on the right side. Based on our staged strategy, the three consecutive cervical hemivertebrae, as the major pathology causing the deformity, were firstly resected by the combined posterior and anterior approach. Six months later, T6 PSO osteotomy was used to correct the structural compensatory thoracic curve. The cervical curve was reduced to 23° while the thoracic curve to 60° after the first-stage surgery, and the thoracic curve was further reduced to 30° after the second-stage surgery. The radiograph at 5-year follow-up showed that both the coronal and sagittal balance were well restored and stabilized, with the occipital tilt reduced from 12° to 0°. Our strategy may provide an option for similar cases with multiple consecutive cervical hemivertebrae and a large structural compensatory thoracic curve, which proved to achieve excellent correction in both the coronal and sagittal planes with acceptable neurologic risk.

Reproducibility of F18-FDG PET radiomic features for different cervical tumor segmentation methods, gray-level discretization, and reconstruction algorithms.

PubMed

Altazi, Baderaldeen A; Zhang, Geoffrey G; Fernandez, Daniel C; Montejo, Michael E; Hunt, Dylan; Werner, Joan; Biagioli, Matthew C; Moros, Eduardo G

2017-11-01

Site-specific investigations of the role of radiomics in cancer diagnosis and therapy are emerging. We evaluated the reproducibility of radiomic features extracted from 18 Flourine-fluorodeoxyglucose ( 18 F-FDG) PET images for three parameters: manual versus computer-aided segmentation methods, gray-level discretization, and PET image reconstruction algorithms. Our cohort consisted of pretreatment PET/CT scans from 88 cervical cancer patients. Two board-certified radiation oncologists manually segmented the metabolic tumor volume (MTV 1 and MTV 2 ) for each patient. For comparison, we used a graphical-based method to generate semiautomated segmented volumes (GBSV). To address any perturbations in radiomic feature values, we down-sampled the tumor volumes into three gray-levels: 32, 64, and 128 from the original gray-level of 256. Finally, we analyzed the effect on radiomic features on PET images of eight patients due to four PET 3D-reconstruction algorithms: maximum likelihood-ordered subset expectation maximization (OSEM) iterative reconstruction (IR) method, fourier rebinning-ML-OSEM (FOREIR), FORE-filtered back projection (FOREFBP), and 3D-Reprojection (3DRP) analytical method. We extracted 79 features from all segmentation method, gray-levels of down-sampled volumes, and PET reconstruction algorithms. The features were extracted using gray-level co-occurrence matrices (GLCM), gray-level size zone matrices (GLSZM), gray-level run-length matrices (GLRLM), neighborhood gray-tone difference matrices (NGTDM), shape-based features (SF), and intensity histogram features (IHF). We computed the Dice coefficient between each MTV and GBSV to measure segmentation accuracy. Coefficient values close to one indicate high agreement, and values close to zero indicate low agreement. We evaluated the effect on radiomic features by calculating the mean percentage differences (d¯) between feature values measured from each pair of parameter elements (i.e. segmentation methods: MTV 1 -MTV 2 , MTV 1 -GBSV, MTV 2 -GBSV; gray-levels: 64-32, 64-128, and 64-256; reconstruction algorithms: OSEM-FORE-OSEM, OSEM-FOREFBP, and OSEM-3DRP). We used |d¯| as a measure of radiomic feature reproducibility level, where any feature scored |d¯| ±SD ≤ |25|% ± 35% was considered reproducible. We used Bland-Altman analysis to evaluate the mean, standard deviation (SD), and upper/lower reproducibility limits (U/LRL) for radiomic features in response to variation in each testing parameter. Furthermore, we proposed U/LRL as a method to classify the level of reproducibility: High- ±1% ≤ U/LRL ≤ ±30%; Intermediate- ±30% < U/LRL ≤ ±45%; Low- ±45 < U/LRL ≤ ±50%. We considered any feature below the low level as nonreproducible (NR). Finally, we calculated the interclass correlation coefficient (ICC) to evaluate the reliability of radiomic feature measurements for each parameter. The segmented volumes of 65 patients (81.3%) scored Dice coefficient >0.75 for all three volumes. The result outcomes revealed a tendency of higher radiomic feature reproducibility among segmentation pair MTV 1 -GBSV than MTV 2 -GBSV, gray-level pairs of 64-32 and 64-128 than 64-256, and reconstruction algorithm pairs of OSEM-FOREIR and OSEM-FOREFBP than OSEM-3DRP. Although the choice of cervical tumor segmentation method, gray-level value, and reconstruction algorithm may affect radiomic features, some features were characterized by high reproducibility through all testing parameters. The number of radiomic features that showed insensitivity to variations in segmentation methods, gray-level discretization, and reconstruction algorithms was 10 (13%), 4 (5%), and 1 (1%), respectively. These results suggest that a careful analysis of the effects of these parameters is essential prior to any radiomics clinical application. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Vestibulospinal control of reflex and voluntary head movement

NASA Technical Reports Server (NTRS)

Boyle, R.; Peterson, B. W. (Principal Investigator)

2001-01-01

Secondary canal-related vestibulospinal neurons respond to an externally applied movement of the head in the form of a firing rate modulation that encodes the angular velocity of the movement, and reflects in large part the input "head velocity in space" signal carried by the semicircular canal afferents. In addition to the head velocity signal, the vestibulospinal neurons can carry a more processed signal that includes eye position or eye velocity, or both (see Boyle on ref. list). To understand the control signals used by the central vestibular pathways in the generation of reflex head stabilization, such as the vestibulocollic reflex (VCR), and the maintenance of head posture, it is essential to record directly from identified vestibulospinal neurons projecting to the cervical spinal segments in the alert animal. The present report discusses two key features of the primate vestibulospinal system. First, the termination morphology of vestibulospinal axons in the cervical segments of the spinal cord is described to lay the structural basis of vestibulospinal control of head/neck posture and movement. And second, the head movement signal content carried by the same class of secondary vestibulospinal neurons during the actual execution of the VCR and during self-generated, or active, rapid head movements is presented.

Postoperative neck symptoms of posterior approach for cervical compressive myelopathy: Expansive open-door laminoplasty vs. segmental partial laminectomy.

PubMed

Otani, Koji; Iwabuchi, Masumi; Sato, Katsuhiko; Konno, Shinichi; Kikuchi, Shinichi

2018-05-18

Laminoplasty is widely accepted as a standard treatment of cervical compressive myelopathy. However, due to the risk of postoperative complications such as neck symptoms, segmental partial laminectomy (SPL) is performed instead, which results in fewer postoperative symptoms. The aim of this study was to describe the difference in the incidence and severity of postoperative neck symptoms between traditional C3-C7 expansive open-door laminoplasty (ELAP) and SPL. A retrospective and comparative study was performed regarding neck complications following the two surgical procedures. Twenty patients underwent SPL, and an additional 20 age- and gender-matched patients underwent traditional C3-C7 ELAP. Preoperative and postoperative JOA scores were measured, and postoperative neck symptoms in both groups were evaluated using a self-administered questionnaire, according to the Neck Pain and Disability Scale. The total incidence of postoperative neck symptoms in the SPL group was similar to that in the ELAP group; however, the severity of symptoms was remarkably lower in the SPL group than in the ELAP group. SPL seems to be a better procedure for reducing postoperative neck symptoms, when compared with C3-C7 ELAP.

Sonographic evaluation of peripheral nerves in subtypes of Guillain-Barré syndrome.

PubMed

Mori, Atsuko; Nodera, Hiroyuki; Takamatsu, Naoko; Maruyama-Saladini, Keiko; Osaki, Yusuke; Shimatani, Yoshimitsu; Kaji, Ryuji

2016-05-15

Sonography of peripheral nerves can depict alteration of nerve sizes that could reflect inflammation and edema in inflammatory and demyelinating neuropathies. Guillain-Barré syndrome (GBS). Information on sonographic comparison of an axonal subtype (acute motor [and sensory] axonal neuropathy [AMAN and AMSAN]) and a demyelinating subtype (acute inflammatory demyelinating polyneuropathy [AIDP]) has been sparse. Sonography of peripheral nerves and cervical nerve roots were prospectively recorded in patients with GBS who were within three weeks of disease onset. Five patients with AIDP and nine with AMAN (n=6)/AMSAN (n=3) were enrolled. The patients with AIDP showed evidence of greater degrees of demyelination (e.g., slower conduction velocities and increased distal latencies) than those with AMAN/AMSAN. The patients with AIDP tended to show enlarged nerves in the proximal segments and in the cervical roots, whereas the patients with AMAN/AMSAN had greater enlargement in the distal neve segment, especially in the median nerve (P = 0.03; Wrist-axilla cross-sectional ratio). In this small study, two subtypes of GBS showed different patterns of involvement that might reflect different pathomechanisms. Copyright © 2016 Elsevier B.V. All rights reserved.

Computational Investigation of Cerebrospinal Fluid Dynamics in the Posterior Cranial Fossa and Cervical Subarachnoid Space in Patients with Chiari I Malformation.

PubMed

Støverud, Karen-Helene; Langtangen, Hans Petter; Ringstad, Geir Andre; Eide, Per Kristian; Mardal, Kent-Andre

2016-01-01

Previous computational fluid dynamics (CFD) studies have demonstrated that the Chiari malformation is associated with abnormal cerebrospinal fluid (CSF) flow in the cervical part of the subarachnoid space (SAS), but the flow in the SAS of the posterior cranial fossa has received little attention. This study extends previous modelling efforts by including the cerebellomedullary cistern, pontine cistern, and 4th ventricle in addition to the cervical subarachnoid space. The study included one healthy control, Con1, and two patients with Chiari I malformation, P1 and P2. Meshes were constructed by segmenting images obtained from T2-weighted turbo spin-echo sequences. CFD simulations were performed with a previously verified and validated code. Patient-specific flow conditions in the aqueduct and the cervical SAS were used. Two patients with the Chiari malformation and one control were modelled. The results demonstrated increased maximal flow velocities in the Chiari patients, ranging from factor 5 in P1 to 14.8 in P2, when compared to Con1 at the level of Foramen Magnum (FM). Maximal velocities in the cervical SAS varied by a factor 2.3, while the maximal flow in the aqueduct varied by a factor 3.5. The pressure drop from the pontine cistern to the cervical SAS was similar in Con1 and P1, but a factor two higher in P2. The pressure drop between the aqueduct and the cervical SAS varied by a factor 9.4 where P1 was the one with the lowest pressure jump and P2 and Con1 differed only by a factor 1.6. This pilot study demonstrates that including the posterior cranial fossa is feasible and suggests that previously found flow differences between Chiari I patients and healthy individuals in the cervical SAS may be present also in the SAS of the posterior cranial fossa.

[Klippel-Feil syndrome with tracheoesophageal fistula, bifid thumb and cerebral angiolipoma.

PubMed

Urdaneta Carruyo, Eliéxer; Rojas Zerpa, Gustavo; Urdaneta Contreras, Adriana; Maldonado Alviarez, Malvy; Brito Rodríguez, Miguel

2016-12-01

The Klippel-Feil syndrome is a congenital malformation of the skull flap involving complex cervical vertebrae and organs, characterized by a classic triad: short neck, limitation of movement of the head due to cervical spine fusion and low hairline in occipital region. It results from an error in the axial skeleton segmentation of the embryo; its incidence is estimated at 1/40,000-42,000 births and predominates in females. The aim of this paper is to describe the clinical picture of a patient with Klippel-Feil syndrome and multiple malformations, including tracheoesophageal fistula, bifid thumb and intracranial lipomas/angiolipomas,that have not been previously described in the syndrome, so it is considered an exceptional finding. Sociedad Argentina de Pediatría.

Deep Learning Nuclei Detection in Digitized Histology Images by Superpixels.

PubMed

Sornapudi, Sudhir; Stanley, Ronald Joe; Stoecker, William V; Almubarak, Haidar; Long, Rodney; Antani, Sameer; Thoma, George; Zuna, Rosemary; Frazier, Shelliane R

2018-01-01

Advances in image analysis and computational techniques have facilitated automatic detection of critical features in histopathology images. Detection of nuclei is critical for squamous epithelium cervical intraepithelial neoplasia (CIN) classification into normal, CIN1, CIN2, and CIN3 grades. In this study, a deep learning (DL)-based nuclei segmentation approach is investigated based on gathering localized information through the generation of superpixels using a simple linear iterative clustering algorithm and training with a convolutional neural network. The proposed approach was evaluated on a dataset of 133 digitized histology images and achieved an overall nuclei detection (object-based) accuracy of 95.97%, with demonstrated improvement over imaging-based and clustering-based benchmark techniques. The proposed DL-based nuclei segmentation Method with superpixel analysis has shown improved segmentation results in comparison to state-of-the-art methods.

Changes in pressure pain sensitivity in latent myofascial trigger points in the upper trapezius muscle after a cervical spine manipulation in pain-free subjects.

PubMed

Ruiz-Sáez, Mariana; Fernández-de-las-Peñas, César; Blanco, Cleofás Rodríguez; Martínez-Segura, Raquel; García-León, Rafael

2007-10-01

This study analyzed the immediate effects on pressure pain threshold (PPT) in latent myofascial trigger points (MTrPs) in the upper trapezius muscle of a single cervical spine manipulation directed at the C3 through C4 level. Seventy-two volunteers (27 men and 46 women; mean age, 31 years; SD, 10 years) participated in this study. Subjects underwent a screening process to establish both the presence of MTrPs in the upper trapezius muscle as described by Simons et al (Myofascial pain and dysfunction: the trigger point manual, vol 2. 3rd ed. Baltimore: Williams & Wilkins, 1999. p. 23-34) and the presence of intervertebral joint dysfunction at the C3 through C4 level by the lateral gliding test for the cervical spine. Subjects were divided randomly into 2 groups: manipulative group, which received a cervical spine manipulation directed at the C3 through C4 level, and a placebo group, which received a sham manual procedure. The outcome measure was the PPT on the MTrP in the upper trapezius muscle ipsilateral to the side of the joint dysfunction, which was assessed pretreatment and 1, 5, and 10 minutes posttreatment by an assessor blinded to the treatment allocation of the subject. The analysis of variance showed a significant effect for time (F = 5.157; P = .02) but not for side (F = 0.234; P = .63). Furthermore, an interaction between group and time was also found (F = 37.240; P < .001). The experimental group showed a trend toward an increase in PPT levels after the manipulative procedure, whereas the control group showed a trend toward a decrease in PPT. Positive within-group effect sizes ranging from medium to small were found in the manipulative group (0.1

Fine crustal and uppermost mantle S-wave velocity structure beneath the Tengchong volcanic area inferred from receiver function and surface-wave dispersion: constraints on magma chamber distribution

NASA Astrophysics Data System (ADS)

Li, Mengkui; Zhang, Shuangxi; Wu, Tengfei; Hua, Yujin; Zhang, Bo

2018-03-01

The Tengchong volcanic area is located in the southeastern margin of the collision zone between the Indian and Eurasian Plates. It is one of the youngest intraplate volcano groups in mainland China. Imaging the S-wave velocity structure of the crustal and uppermost mantle beneath the Tengchong volcanic area is an important means of improving our understanding of its volcanic activity and seismicity. In this study, we analyze teleseismic data from nine broadband seismic stations in the Tengchong Earthquake Monitoring Network. We then image the crustal and uppermost mantle S-wave velocity structure by joint analysis of receiver functions and surface-wave dispersion. The results reveal widely distributed low-velocity zones. We find four possible magma chambers in the upper-to-middle crust and one in the uppermost mantle. The chamber in the uppermost mantle locates in the depth range from 55 to 70 km. The four magma chambers in the crust occur at different depths, ranging from the depth of 7 to 25 km in general. They may be the heat sources for the high geothermal activity at the surface. Based on the fine crustal and uppermost mantle S-wave velocity structure, we propose a model for the distribution of the magma chambers.

Comparison of axial and flexural stresses in lordosis and three buckled configurations of the cervical spine.

PubMed

Harrison, D E; Harrison, D D; Janik, T J; William Jones, E; Cailliet, R; Normand, M

2001-05-01

To calculate and compare combined axial and flexural stresses in lordosis versus buckled configurations of the sagittal cervical curve. Digitized measurements from lateral cervical radiographs of four different shapes were used to calculate axial loads and bending moments on the vertebral bodies of C2-C7.Background. Osteoarthritis and spinal degeneration are factors in neck and back pain. Calculations of stress in clinically occurring configurations of the sagittal cervical spine are rare. Center of gravity of the head (inferior-posterior sella turcica) and vertebral body margins were digitized on four different lateral cervical radiographs: lordosis, kyphosis, and two "S"-shapes. Polynomials (seventh degree) and stress concentrations on the concave and convex margins were derived for the shape of the sagittal cervical curvatures from C1 to T1. Moments of inertia were determined from digitizing and the use of an elliptical shell model of cross-section. Moment arms from a vertical line through the center of gravity of the head to the atlas and scaled neck extensor moment arms from the literature were used to compute the vertical component of extensor muscle effort. Segmental lever arms were calculated from a vertical line through C1 to each vertebra. In lordosis, anterior and posterior stresses in the vertebral body are nearly uniform and minimal. In kyphotic areas, combined stresses changed from tension to compression at the anterior vertebral margins and were very large (6-10 times as large in magnitude) compared to lordosis. In kyphotic areas at the posterior vertebral body, the combined stresses changed from compression (in lordosis) to tension. The stresses in kyphotic areas are very large and opposite in direction compared to a normal lordosis. This analysis provides the basis for the formation of osteophytes (Wolff's Law) on the anterior margins of vertebrae in kyphotic regions of the sagittal cervical curve. This indicates that any kyphosis is an undesirable configuration in the cervical spine. Relevance. Osteophytes and osteoarthritis are found at areas of altered stress and strain. Axial and flexural stresses at kyphotic areas in the sagittal cervical spine are abnormally high.

What is the superior surgical strategy for bi-level cervical spondylosis-anterior cervical disc replacement or anterior cervical decompression and fusion?: A meta-analysis from 11 studies.

PubMed

Zhao, He; Duan, Li-Jun; Gao, Yu-Shan; Yang, Yong-Dong; Tang, Xiang-Sheng; Zhao, Ding-Yan; Xiong, Yang; Hu, Zhen-Guo; Li, Chuan-Hong; Yu, Xing

2018-03-01

Nowadays, anterior cervical artificial disc replacement (ACDR) has achieved favorable outcomes in treatment for patients with single-level cervical spondylosis. However, It is still controversial that whether or not it will become a potent therapeutic alternation in treating 2 contiguous levels cervical spondylosis compared with anterior cervical decompression and fusion (ACDF). Therefore, we conducted a systematic review and meta-analysis to compare the efficacy and safety of ACDR and ACDF in patients with 2 contiguous levels cervical spondylosis. According to the computer-based online search, PubMed, Embase, Web of Science, and Cochrane Library for articles published before July 1, 2017 were searched. The following outcome measures were extracted: neck disability index (NDI), visual analog scale (VAS) neck, VAS arm, Short Form (SF)-12 mental component summary (MCS), SF-12 physical component summary (PCS), overall clinical success (OCS), patient satisfaction (PS), device-related adverse event (DRAE), subsequent surgical intervention (SSI), neurological deterioration (ND), and adjacent segment degeneration (ASD). Methodological quality was evaluated independently by 2 reviewers using the Furlan for randomized controlled trial (RCT) and MINORS scale for clinical controlled trials (CCT). The chi-squared test and Higgin I test were used to evaluate the heterogeneity. A P < .10 for the chi-squared test or I values exceeding 50% indicated substantial heterogeneity and a random-effect model was applied; otherwise, a fixed-effect model was used. All quantitative data were analyzed by the Review Manager 5.2 (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). Nine RCTs and 2 CCT studies containing 2715 patients were included for this meta-analysis. The pooled analysis indicated that the ACDR group is superior to ACDF in NDI, VAS neck, PCS score, OCS, PS, DRAE, ASD, and SSI. However, the pooled results indicate that there was no significant difference in the ND, VAS arm and in MCS score. The present meta-analysis suggests that for bi-level cervical spondylosis, ACDR appears to provide superior clinical effectiveness and safety effects than ACDF. In the future, more high-quality RCTs are warranted to enhance this conclusion.

The surgical treatment of instability of the upper part of the cervical spine in children and adolescents.

PubMed

Koop, S E; Winter, R B; Lonstein, J E

1984-03-01

In a retrospective review of the cases of thirteen skeletally immature children and adolescents (four to eighteen years old) with instability of the upper part of the cervical spine (occiput to fifth cervical vertebra), we determined the efficacy of posterior arthrodesis and halo-cast immobilization in the management of this condition. The patients were divided into two groups: those with congenital vertebral anomalies alone (fusion or structural defects, or both) and those with cervical anomalies and systemic disorders (dwarfism, juvenile rheumatoid arthritis, Down syndrome, and cerebral palsy). Two patterns of instability were found: instabilities at intervertebral joints adjacent to vertebral fusions, and instabilities located in vertebral defects. For all patients treatment included a posterior arthrodesis with external immobilization by a halo cast, and in two patients internal fixation with wire was also used. Solid arthrodesis was obtained in the twelve patients who were treated with autogenous grafts (iliac cancellous bone in eleven and rib bone in one), and a non-union developed in a child who was treated with bank-bone rib segments. Posterior cervical arthrodesis with wire fixation carries some risk of neural injury and often is not applicable in children with anomalous vertebrae. Spine fusion using delicate exposure, decortication using an air-drill, and placement of autogenous cancellous iliac grafts with external immobilization by a halo cast minimizes the risk of neural damage and is a reliable way to obtain a solid arthrodesis.

Magnetic Resonance Imaging of Three-Dimensional Cervical Anatomy in the Second and Third Trimester

PubMed Central

HOUSE, Michael; BHADELIA, Rafeeque A.; MYERS, Kristin; SOCRATE, Simona

2009-01-01

OBJECTIVE Although a short cervix is known to be associated with preterm birth, the patterns of three-dimensional, anatomic changes leading to a short cervix are unknown. Our objective was to 1) construct three-dimensional anatomic models during normal pregnancy and 2) use the models to compare cervical anatomy in the second and third trimester. STUDY DESIGN A cross sectional study was performed in a population of patients referred to magnetic resonance imaging (MRI) for a fetal indication. Using magnetic resonance images for guidance, three-dimensional solid models of the following anatomic structures were constructed: amniotic cavity, uterine wall, cervical stroma, cervical mucosa and anterior vaginal wall. To compare cervical anatomy in the second and third trimester, models were matched according the size of the bony pelvis. RESULTS Fourteen patients were imaged and divided into two groups according to gestational age: 20 – 24 weeks (n=7)) and 31 – 36 weeks (n=7). Compared to the second trimester, the third trimester was associated with significant descent of the amniotic sac. (p=.02). Descent of the amniotic sac was associated with modified anatomy of the uterocervical junction. These 3-dimensional changes were associated with a cervix that appeared shorter in the third trimester. CONCLUSION We report a technique for constructing MRI-based, three-dimensional anatomic models during pregnancy. Compared to the second trimester, the third trimester is associated with three-dimensional changes in the cervix and lower uterine segment. PMID:19297070

Swallow segmentation with artificial neural networks and multi-sensor fusion.

PubMed

Lee, Joon; Steele, Catriona M; Chau, Tom

2009-11-01

Swallow segmentation is a critical precursory step to the analysis of swallowing signal characteristics. In an effort to automatically segment swallows, we investigated artificial neural networks (ANN) with information from cervical dual-axis accelerometry, submental MMG, and nasal airflow. Our objectives were (1) to investigate the relationship between segmentation performance and the number of signal sources and (2) to identify the signals or signal combinations most useful for swallow segmentation. Signals were acquired from 17 healthy adults in both discrete and continuous swallowing tasks using five stimuli. Training and test feature vectors were constructed with variances from single or multiple signals, estimated within 200 ms moving windows with 50% overlap. Corresponding binary target labels (swallow or non-swallow) were derived by manual segmentation. A separate 3-layer ANN was trained for each participant-signal combination, and all possible signal combinations were investigated. As more signal sources were included, segmentation performance improved in terms of sensitivity, specificity, accuracy, and adjusted accuracy. The combination of all four signal sources achieved the highest mean accuracy and adjusted accuracy of 88.5% and 89.6%, respectively. A-P accelerometry proved to be the most discriminatory source, while the inclusion of MMG or nasal airflow resulted in the least performance improvement. These findings suggest that an ANN, multi-sensor fusion approach to segmentation is worthy of further investigation in swallowing studies.

Cervical spinal canal narrowing in idiopathic syringomyelia.

PubMed

Struck, Aaron F; Carr, Carrie M; Shah, Vinil; Hesselink, John R; Haughton, Victor M

2016-08-01

The cervical spine in Chiari I patient with syringomyelia has significantly different anteroposterior diameters than it does in Chiari I patients without syringomyelia. We tested the hypothesis that patients with idiopathic syringomyelia (IS) also have abnormal cervical spinal canal diameters. The finding in both groups may relate to the pathogenesis of syringomyelia. Local institutional review boards approved this retrospective study. Patients with IS were compared to age-matched controls with normal sagittal spine MR. All subjects had T1-weighted spin-echo (500/20) and T2-weighted fast spin-echo (2000/90) sagittal cervical spine images at 1.5 T. Readers blinded to demographic data and study hypothesis measured anteroposterior diameters at each cervical level. The spinal canal diameters were compared with a Mann-Whitney U test. The overall difference was assessed with a Friedman test. Seventeen subjects were read by two reviewers to assess inter-rater reliability. Fifty IS patients with 50 age-matched controls were studied. IS subjects had one or more syrinxes varying from 1 to 19 spinal segments. Spinal canal diameters narrowed from C1 to C3 and then enlarged from C5 to C7 in both groups. Diameters from C2 to C4 were narrower in the IS group (p < 0.005) than in controls. The ratio of the C3 to the C7 diameters was also smaller (p = 0.004) in IS than controls. Collectively, the spinal canal diameters in the IS were significantly different from controls (Friedman test p < 0.0001). Patients with IS have abnormally narrow upper and mid cervical spinal canal diameters and greater positive tapering between C3 and C7.

Cervical spine injury: a ten-year multicenter analysis of evolution of care and risk factors for poor outcome in southeast Nigeria.

PubMed

Uche, E O; Nwankwo, O E; Okorie, E; Nnezianya, I

2015-01-01

Retrospective study. To describe the evolution of care and risk factors for poor outcome in patients with cervical spine injury (CSI) treated at three centers in southeast Nigeria. Nigeria, southeast. A 10-year retrospective multicenter analysis of patients with CSI, managed at three centers in southeast Nigeria, from January 2003 to December 2012. Two hundred and seven patients (55%) had CSI out of 377 spinal injury cases in the three study centers, but 195 cases had complete records and were studied. There were 148 males and 47 females. The age range was 3-74 years with a mean of 32.6 (± 1.9) years 95% CI. Most injuries (149 cases) resulted from motor vehicular accidents (MVA). The C5 spinal level was involved in 75 (38%) cases One hundred and seventeen patients (60%) presented with American Spinal Injury Association A (ASIA A) injury. CSI care evolved from the application of a Minerva jacket or cervical traction only to cervical traction and spinal fusion resulting in a reduction in hospital stay (F = 52.5, DF (2, 3) P < 0.05). When compared to 51 patients with incomplete injuries, who improved in neurologic al status at discharge, only three patients with ASIA grade A experienced some improvement. The mortality rate from our series is 16% (32 patients). Those who died were more likely to have a complete injury (25 patients) or a high cervical injury (X² = 61.2, P < 0.05) among other factors. The cervical spine is the most commonly injured spinal segment in southeast Nigeria. Although treatment evolution has resulted in reduction of hospital stay, the associated mortality risk still remains high.

Neural space and biomechanical integrity of the developing cervical spine in compression.

PubMed

Nuckley, David J; Van Nausdle, Joseph A; Eck, Michael P; Ching, Randal P

2007-03-15

A factorial study design was used to examine the biomechanical and neuroprotective integrity of the cervical spine throughout maturation using a postmortem baboon model. To investigate changes with spinal development that affect the neuroprotective ability of the cervical spine in compressive loading. Child spinal cord injuries claim and debilitate thousands of children in the United States each year. Many of these injuries are diagnostically and mechanistically difficult to classify, treat, and prevent. Biomechanical studies on maturing spinal tissues have identified decreased stiffness and tolerance characteristics for children compared with adults. Unfortunately, while neurologic deficit typically dictates functional outcome, no previous studies have examined the neuroprotective role of the pediatric cervical spine. Twenty-two postmortem baboon cervical spines across the developmental age spectrum were tested. Two functional spinal unit segments (Oc-C2, C3-C5, and C6-T1) were instrumented with transducers to measure dynamic changes in the spinal canal. These tissues were compressed to 70% strain dynamically, and the resultant mechanics and spinal canal occlusions were recorded. Classic injury patterns were observed in all of the specimens tested. The compressive mechanics exhibited a significant age relationship (P < 0.0001). Furthermore, while the peak-percent spinal canal occlusion was not age dependent, the percent occlusion just before failure did demonstrate a significant decrease with advancing age (P = 0.0001). The neuroprotective ability of the cervical spine preceding failure appears to be age dependent, where the young spine can produce greater spinal canal occlusions without failure than its adult counterpart. The overall percent of the spinal canal occluded during a compression injury was not age dependent; however, these data reveal the neuroprotective ability of the child spine to be more sensitive as an injury predictor than the biomechanical fracture data.

Very late complications of cervical arthroplasty: results of 2 controlled randomized prospective studies from a single investigator site.

PubMed

Hacker, Francis M; Babcock, Rebecca M; Hacker, Robert J

2013-12-15

Prospective, single-site, randomized, Food and Drug Administration-approved investigational device exemption clinical trials of 2 cervical arthroplasty (CA) devices. To evaluate complications with CA occurring more than 4 years after the surgical procedure in Food and Drug Administration clinical trials of the Bryan and Prestige LP arthroplasty devices. Reports of several randomized clinical studies have shown CA to be a safe and effective alternative to anterior cervical fusion in the treatment of degenerative cervical disc disorders. A majority include follow-up intervals of 4 years or less. Between 2002 and 2006, 94 patients were enrolled in Food and Drug Administration studies of the Bryan and Prestige LP cervical disc devices. Charts, imaging studies, and hospital records were reviewed for those who underwent arthroplasty and returned more than 4 years after their surgical procedure with neck-related pain or dysfunction. Excluding adjacent segment disease that occurred with a similar rate for patients who underwent fusion and arthroplasty, 5 patients, all treated with arthroplasty, returned for evaluation of neck and arm symptoms between 48 and 72 months after surgery. Four patients had peridevice vertebral body bone loss. One patient had posterior device migration and presented with myelopathy. Three required revision surgery and 2 were observed. Four patients maintained follow-up and reported stabilization or improvement in symptoms. Despite their similarities, CA and fusion are not equivalent procedures in this study in regard to very late complications. Similar to large joint arthroplasty, delayed device-related complications may occur with CA. These complications commenced well beyond the time frame for complications associated with more traditional cervical spine procedures. Both patients and surgeons should be aware of the potential for very late device-related complications occurring with CA and the need for revision surgery. 1.

Dynamic foraminal dimensions during neck extension and rotation in fusion and artificial disc replacement: an observational study.

PubMed

Yeni, Yener N; Baumer, Timothy; Oravec, Daniel; Basheer, Azam; McDonald, Colin P; Bey, Michael J; Bartol, Stephen W; Chang, Victor

2018-04-01

Changes in the dimensions of the cervical neural foramina (CNF) are considered to be a key factor in nerve root compression and development of cervical radiculopathy. However, to what extent foraminal geometry differs between patients who underwent anterior cervical discectomy and fusion (ACDF) and those who underwent total disc arthroplasty with an artificial disc (AD) during physiological motion is largely unknown. The objective of this study is to compare CNF dimensions during physiological neck motion between ACDF and AD. This is a retrospective comparative analysis of prospectively collected, consecutive, non-randomized series of patients at a single institution. A total of 16 single-level C5-C6 ACDF (4 males, 12 females; 28-71 years) and 7 single-level C5-C6 cervical arthroplasty patients (3 males, 4 females; 38-57 years), at least 12 months after surgery (23.6±6.8 months) were included. Patient demographics, preoperative magnetic resonance imaging (MRI)-based measurements of cervical spine degeneration, and 2-year postoperative measurements of dynamic foraminal geometry were the outcome measures. Biplane X-ray images were acquired during axial neck rotation and neck extension. A computed tomography scan was also acquired from C3 to the first thoracic vertebrae. The subaxial cervical vertebrae (C3-C7) were reconstructed into three-dimensional (3D) bone models for use with model-based tracking. Foraminal height (FH) was calculated as the 3D distance between the superior point of the inferior pedicle and the inferior point of the superior pedicle using custom software. Foraminal width (FW) was similarly calculated as the 3D distance between the anterolateral aspect of the superior vertebral body inferior notch and the posterolateral aspect of the inferior vertebral body superior notch. Dynamic foraminal dimensions were quantified as the minimum (FH.Min, FW.Min), the range (FH.Range, FW.Range), and the median (FH.Med, FW.Med) of each trial and then averaged over trials. Mixed model analysis of variance framework was used to examine the differences between ACDF and AD groups. The initial severity of disc degeneration as determined from preoperative MRI images was introduced as covariates in the models. At the operated level (C5-C6), FH.Med and FH.Range were smaller in ACDF than in AD during axial rotation and neck extension (p<.003 to p<.05). At the superior adjacent level (C4-C5), no significant difference was found. At the inferior adjacent level (C6-C7), FW.Range was greater in ACDF than in AD during axial rotation and extension (p<.05). At the non-adjacent level (C3-C4), FW.Range was greater in ACDF than in AD during extension (p<.008). This study demonstrated decreases in foraminal dimensions and their range for ACDF compared with AD at the operated level. In contrast, it demonstrated increases in the range of foraminal dimensions during motion for ACDF compared with AD at the non-operated segments. Together, these data support the notion that increased mobility at the non-operated segments after ACDF may contribute to a greater risk for adjacent segment degeneration. Because of the significant presence of range variables in the findings, the current data also indicate that a dynamic evaluation is likely more appropriate for evaluation of the differences in foramina between ACDF and AD than a static evaluation. Copyright © 2017 Elsevier Inc. All rights reserved.

A comparative analysis of DBSCAN, K-means, and quadratic variation algorithms for automatic identification of swallows from swallowing accelerometry signals.

PubMed

Dudik, Joshua M; Kurosu, Atsuko; Coyle, James L; Sejdić, Ervin

2015-04-01

Cervical auscultation with high resolution sensors is currently under consideration as a method of automatically screening for specific swallowing abnormalities. To be clinically useful without human involvement, any devices based on cervical auscultation should be able to detect specified swallowing events in an automatic manner. In this paper, we comparatively analyze the density-based spatial clustering of applications with noise algorithm (DBSCAN), a k-means based algorithm, and an algorithm based on quadratic variation as methods of differentiating periods of swallowing activity from periods of time without swallows. These algorithms utilized swallowing vibration data exclusively and compared the results to a gold standard measure of swallowing duration. Data was collected from 23 subjects that were actively suffering from swallowing difficulties. Comparing the performance of the DBSCAN algorithm with a proven segmentation algorithm that utilizes k-means clustering demonstrated that the DBSCAN algorithm had a higher sensitivity and correctly segmented more swallows. Comparing its performance with a threshold-based algorithm that utilized the quadratic variation of the signal showed that the DBSCAN algorithm offered no direct increase in performance. However, it offered several other benefits including a faster run time and more consistent performance between patients. All algorithms showed noticeable differentiation from the endpoints provided by a videofluoroscopy examination as well as reduced sensitivity. In summary, we showed that the DBSCAN algorithm is a viable method for detecting the occurrence of a swallowing event using cervical auscultation signals, but significant work must be done to improve its performance before it can be implemented in an unsupervised manner. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Comparative Analysis of DBSCAN, K-Means, and Quadratic Variation Algorithms for Automatic Identification of Swallows from Swallowing Accelerometry Signals

PubMed Central

Dudik, Joshua M.; Kurosu, Atsuko; Coyle, James L

2015-01-01

Background Cervical auscultation with high resolution sensors is currently under consideration as a method of automatically screening for specific swallowing abnormalities. To be clinically useful without human involvement, any devices based on cervical auscultation should be able to detect specified swallowing events in an automatic manner. Methods In this paper, we comparatively analyze the density-based spatial clustering of applications with noise algorithm (DBSCAN), a k-means based algorithm, and an algorithm based on quadratic variation as methods of differentiating periods of swallowing activity from periods of time without swallows. These algorithms utilized swallowing vibration data exclusively and compared the results to a gold standard measure of swallowing duration. Data was collected from 23 subjects that were actively suffering from swallowing difficulties. Results Comparing the performance of the DBSCAN algorithm with a proven segmentation algorithm that utilizes k-means clustering demonstrated that the DBSCAN algorithm had a higher sensitivity and correctly segmented more swallows. Comparing its performance with a threshold-based algorithm that utilized the quadratic variation of the signal showed that the DBSCAN algorithm offered no direct increase in performance. However, it offered several other benefits including a faster run time and more consistent performance between patients. All algorithms showed noticeable differen-tiation from the endpoints provided by a videofluoroscopy examination as well as reduced sensitivity. Conclusions In summary, we showed that the DBSCAN algorithm is a viable method for detecting the occurrence of a swallowing event using cervical auscultation signals, but significant work must be done to improve its performance before it can be implemented in an unsupervised manner. PMID:25658505

High-flow bypass with radial artery graft followed by internal carotid artery ligation for large or giant aneurysms of cavernous or cervical portion: clinical results and cognitive performance.

PubMed

Ono, Hideaki; Inoue, Tomohiro; Tanishima, Takeo; Tamura, Akira; Saito, Isamu; Saito, Nobuhito

2018-04-01

High-flow bypass followed by ligation of the internal carotid artery (ICA) is an effective treatment, but the impact of abrupt occlusion of the ICA is unpredictable, especially on postoperative cognitive function. The present study evaluated the clinical results as well as cognitive performances after high-flow bypass using radial artery graft (RAG) with supportive superficial temporal artery (STA)-middle cerebral artery (MCA) bypass, followed by ICA ligation. Ten consecutive patients underwent high-flow bypass surgery for large or giant ICA aneurysms of cavernous or cervical portion. Demographics, clinical information, magnetic resonance (MR) imaging, computed tomography, digital subtraction angiography (DSA), intraoperative somatosensory evoked potentials, neuropsychological examinations including the Wechsler Adult Intelligence Scale-Third Edition and the Wechsler Memory Scale-Revised (WMS-R), and follow-up data were analyzed. The aneurysm was located on the cavernous segment in eight cases and cervical segment in two cases, and mean aneurysm size was 27.9 mm. Postoperative DSA demonstrated robust bypass flow from the external carotid artery to MCA via the RAG, and no anterograde flow into the aneurysm. No patient showed new symptoms after the operation. Follow-up clinical study and MR imaging were performed in nine patients and showed no additional ischemic lesion compared with preoperative imaging. Seven patients completed neuropsychological examinations before and after surgery. All postoperative scores except WMS-R composite memory score slightly improved. High-flow bypass followed by ICA ligation can achieve good clinical outcomes. Successful high-flow bypass using RAG with supportive STA-MCA bypass and ICA ligation does not adversely affect postoperative cognitive function.

Duodenal and Other Gastrointestinal Toxicity in Cervical and Endometrial Cancer Treated With Extended-Field Intensity Modulated Radiation Therapy to Paraaortic Lymph Nodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poorvu, Philip D.; Sadow, Cheryl A.; Townamchai, Kanokpis

2013-04-01

Purpose: To characterize the rates of acute and late duodenal and other gastrointestinal (GI) toxicities among patients treated for cervical and endometrial cancers with extended-field intensity modulated radiation therapy (EF-IMRT) to the paraaortic nodes and to analyze dose-volume relationships of GI toxicities. Methods and Materials: Fifty-three patients with endometrial or cervical cancer underwent EF-IMRT to the paraaortic nodes, of whom 46 met the inclusion criteria for GI toxicity and 45 for duodenal toxicity analysis. The median prescribed dose to the paraaortic nodes was 54 Gy (range, 41.4-65 Gy). The 4 duodenal segments, whole duodenum, small bowel loops, peritoneum, and peritoneummore » plus retroperitoneal segments of colon were contoured retrospectively, and dosimetric analysis was performed to identify dose-volume relationships to grade ≥3 acute (<90 day) and late (≥90 day) GI toxicity. Results: Only 3/46 patients (6.5%) experienced acute grade ≥3 GI toxicity and 3/46 patients (6.5%) experienced late grade ≥3 GI toxicity. The median dose administered to these 6 patients was 50.4 Gy. One of 12 patients who received 63 to 65 Gy at the level of the renal hilum experienced grade 3 GI toxicity. Dosimetric analysis of patients with and without toxicity revealed no differences between the mean absolute or fractional volumes at any 5-Gy interval between 5 Gy and the maximum dose. None of the patients experienced duodenal toxicity. Conclusions: Treatment of paraaortic nodes with IMRT is associated with low rates of GI toxicities and no duodenal-specific toxicity, including patients treated with concurrent chemotherapy. This technique may allow sufficient dose sparing of the bowel to enable safe dose escalation to at least 65 Gy.« less

Deep Learning Nuclei Detection in Digitized Histology Images by Superpixels

PubMed Central

Sornapudi, Sudhir; Stanley, Ronald Joe; Stoecker, William V.; Almubarak, Haidar; Long, Rodney; Antani, Sameer; Thoma, George; Zuna, Rosemary; Frazier, Shelliane R.

2018-01-01

Background: Advances in image analysis and computational techniques have facilitated automatic detection of critical features in histopathology images. Detection of nuclei is critical for squamous epithelium cervical intraepithelial neoplasia (CIN) classification into normal, CIN1, CIN2, and CIN3 grades. Methods: In this study, a deep learning (DL)-based nuclei segmentation approach is investigated based on gathering localized information through the generation of superpixels using a simple linear iterative clustering algorithm and training with a convolutional neural network. Results: The proposed approach was evaluated on a dataset of 133 digitized histology images and achieved an overall nuclei detection (object-based) accuracy of 95.97%, with demonstrated improvement over imaging-based and clustering-based benchmark techniques. Conclusions: The proposed DL-based nuclei segmentation Method with superpixel analysis has shown improved segmentation results in comparison to state-of-the-art methods. PMID:29619277

Effects of cervical arthrodesis and arthroplasty on neck response during a simulated frontal automobile collision.

PubMed

White, Nicholas A; Moreno, Daniel P; Brown, Philip J; Gayzik, F Scott; Hsu, Wesley; Powers, Alexander K; Stitzel, Joel D

2014-09-01

Whereas arthrodesis is the most common surgical intervention for the treatment of symptomatic cervical degenerative disc disease, arthroplasty has become increasingly more popular over the past decade. Although literature exists comparing the effects of anterior cervical discectomy and fusion and cervical total disc replacement (CTDR) on neck kinematics and loading, the vast majority of these studies apply only quasi-static, noninjurious loading conditions to a segment of the cervical spine. The objective of this study was to investigate the effects of arthrodesis and arthroplasty on biomechanical neck response during a simulated frontal automobile collision with air bag deployment. This study used a full-body, 50th percentile seated male finite element (FE) model to evaluate neck response during a dynamic impact event. The cervical spine was modified to simulate either an arthrodesis or arthroplasty procedure at C5-C6. Five simulations of a belted driver, subjected to a 13.3 m/s ΔV frontal impact with air bag deployment, were run in LS-DYNA with the Global Human Body Models Consortium full-body FE model. The first simulation used the original model, with no modifications to the neck, whereas the remaining four were modified to represent either interbody arthrodesis or arthroplasty of C5-C6. Cross-sectional forces and moments at the C5 and C6 cervical levels of the neck, along with interbody and facet forces between C5 and C6, were reported. Adjacent-level, cross-sectional neck loading was maintained in all simulations without exceeding any established injury thresholds. Interbody compression was greatest for the CTDRs, and interbody tension occurred only in the fused and nonmodified spines. Some interbody separation occurred between the superior and inferior components of the CTDRs during flexion-induced tension of the cervical spine, increasing the facet loads. This study evaluated the effects of C5-C6 cervical arthrodesis and arthroplasty on neck response during a simulated frontal automobile impact. Although cervical arthrodesis and arthroplasty at C5-C6 did not appear to significantly alter the adjacent-level, cross-sectional neck responses during a simulated frontal automobile impact, key differences were noted in the interbody and facet loading. Copyright © 2014 Elsevier Inc. All rights reserved.

Uppermost oceanic crust structure and properties from multichannel seismic data at the Alaska subduction zone

NASA Astrophysics Data System (ADS)

Becel, A.; Carton, H. D.; Shillington, D. J.

2017-12-01

The most heterogeneous, porous and permeable layer within a subducting oceanic crust is the uppermost layer called Layer 2A. This layer, made of extrusive basalts, forms at the ridge axis and persists as a thin ( 600 m) low-velocity cap in old crust. Nearing the trench axis, when oceanic plate bends, normal faults can be formed or reactivated at the outer-rise allowing a more vigorous hydrothermal circulation to resume within this layer. Porosity and heterogeneity within this layer are important to assess because these parameters might have a profound impact on subduction zone processes. However, conventional refraction data quality is rarely good enough to look into detail into the properties of the uppermost oceanic layer. Here we use 2D marine long-offset multi-channel seismic (MCS) reflection data collected offshore of the Alaska Peninsula during the ALEUT Program. The dataset was acquired aboard the R/V Marcus Langseth with a 636-channels, 8-km long streamer. We present initial results from three 140 km long profiles across the 52-56Myr old incoming Pacific oceanic crust formed at fast spreading rate: two perpendicular margin and one parallel margin profiles. Those profiles are located outboard of the Shumagin gaps. Outboard of this subduction zone segment, abundant bending related normal faults are imaged and concentrated within 50-60 km of the trench. Long-offset MCS data exhibit a prominent triplication that includes postcritical reflections and turning waves within the upper crust at offsets larger than 3 km. The triplication suggests the presence of a velocity discontinuity within the upper oceanic crust. We follow a systematic and uniform approach to extract upper crustal post-critical reflections and add them to them to the vertical incidence MCS images. Images reveal small-scale variations in the thickness of the Layer 2A and the strength of its base along the profiles. The second step consists of the downward continuation followed by travel-time modeling of the long streamer data. The downward continuation of the shots and receivers appears to be essential to unravel the refracted energy in the upper crust and is used to determine the detailed velocity-depth structure.

Spinal cord grey matter segmentation challenge.

PubMed

Prados, Ferran; Ashburner, John; Blaiotta, Claudia; Brosch, Tom; Carballido-Gamio, Julio; Cardoso, Manuel Jorge; Conrad, Benjamin N; Datta, Esha; Dávid, Gergely; Leener, Benjamin De; Dupont, Sara M; Freund, Patrick; Wheeler-Kingshott, Claudia A M Gandini; Grussu, Francesco; Henry, Roland; Landman, Bennett A; Ljungberg, Emil; Lyttle, Bailey; Ourselin, Sebastien; Papinutto, Nico; Saporito, Salvatore; Schlaeger, Regina; Smith, Seth A; Summers, Paul; Tam, Roger; Yiannakas, Marios C; Zhu, Alyssa; Cohen-Adad, Julien

2017-05-15

An important image processing step in spinal cord magnetic resonance imaging is the ability to reliably and accurately segment grey and white matter for tissue specific analysis. There are several semi- or fully-automated segmentation methods for cervical cord cross-sectional area measurement with an excellent performance close or equal to the manual segmentation. However, grey matter segmentation is still challenging due to small cross-sectional size and shape, and active research is being conducted by several groups around the world in this field. Therefore a grey matter spinal cord segmentation challenge was organised to test different capabilities of various methods using the same multi-centre and multi-vendor dataset acquired with distinct 3D gradient-echo sequences. This challenge aimed to characterize the state-of-the-art in the field as well as identifying new opportunities for future improvements. Six different spinal cord grey matter segmentation methods developed independently by various research groups across the world and their performance were compared to manual segmentation outcomes, the present gold-standard. All algorithms provided good overall results for detecting the grey matter butterfly, albeit with variable performance in certain quality-of-segmentation metrics. The data have been made publicly available and the challenge web site remains open to new submissions. No modifications were introduced to any of the presented methods as a result of this challenge for the purposes of this publication. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

A systematic review of definitions and classification systems of adjacent segment pathology.

PubMed

Kraemer, Paul; Fehlings, Michael G; Hashimoto, Robin; Lee, Michael J; Anderson, Paul A; Chapman, Jens R; Raich, Annie; Norvell, Daniel C

2012-10-15

Systematic review. To undertake a systematic review to determine how "adjacent segment degeneration," "adjacent segment disease," or clinical pathological processes that serve as surrogates for adjacent segment pathology are classified and defined in the peer-reviewed literature. Adjacent segment degeneration and adjacent segment disease are terms referring to degenerative changes known to occur after reconstructive spine surgery, most commonly at an immediately adjacent functional spinal unit. These can include disc degeneration, instability, spinal stenosis, facet degeneration, and deformity. The true incidence and clinical impact of degenerative changes at the adjacent segment is unclear because there is lack of a universally accepted classification system that rigorously addresses clinical and radiological issues. A systematic review of the English language literature was undertaken and articles were classified using the Grades of Recommendation Assessment, Development, and Evaluation criteria. RESULTS.: Seven classification systems of spinal degeneration, including degeneration at the adjacent segment, were identified. None have been evaluated for reliability or validity specific to patients with degeneration at the adjacent segment. The ways in which terms related to adjacent segment "degeneration" or "disease" are defined in the peer-reviewed literature are highly variable. On the basis of the systematic review presented in this article, no formal classification system for either cervical or thoracolumbar adjacent segment disorders currently exists. No recommendations regarding the use of current classification of degeneration at any segments can be made based on the available literature. A new comprehensive definition for adjacent segment pathology (ASP, the now preferred terminology) has been proposed in this Focus Issue, which reflects the diverse pathology observed at functional spinal units adjacent to previous spinal reconstruction and balances detailed stratification with clinical utility. A comprehensive classification system is being developed through expert opinion and will require validation as well as peer review. Strength of Statement: Strong.

Comparison of Three Reconstructive Techniques in the Surgical Management of Patients With Four-Level Cervical Spondylotic Myelopathy.

PubMed

Li, Zhonghai; Wang, Huadong; Tang, Jiaguang; Ren, Dongfeng; Li, Li; Hou, Shuxun; Zhang, Hailong; Hou, Tiesheng

2017-05-15

Retrospective clinical series. To compare perioperative parameters, clinical outcomes, radiographic parameters, and complication rates of three reconstructive techniques after the anterior decompression of four-level cervical spondylotic myelopathy (CSM). At present, the decision to treat multilevel CSM, especially four-level CSM, remains controversial. No one compares multilevel anterior cervical discectomy and fusion (mACDF), segmental anterior cervical corpectomy and fusion (sACCF) to multilevel anterior cervical discectomy and fusion with cage alone (mACDF-CA) in four-level constructs. Between July 2006 and February 2014, 97 consecutive patients with four-level CSM were enrolled in this study and divided into sACCF (n = 39) group, mACDF (n = 31) group, and mACDF-CA (n = 27) group. The study compared perioperative parameters, complication rates, clinical and radiologic parameters of three reconstructive techniques after the anterior decompression of four-level CSM. The mACDF-CA group had the least bleeding and cost of index surgery compared with the sACCF group having the most bleeding and cost. Although significant pain relief and functional activity improvement have been achieved in the three groups at the final follow-up, there was no significant difference in the Japanese Orthopedic Association, SF-36 and NDI scores among the three groups (P >0.05). The mACDF group maintained the best cervical lordosis at the final follow-up, compared with the sACCF group maintained the worst cervical lordosis. Solid fusion was achieved in 87.1% of subjects in sACCF group, 90.3% in mACDF, and in 88.9% in mACDF-CA. The mACDF-CA group had a higher rate of subsidence and lower rate of dysphagia than other two groups. mACDF-CA can be considered an effective and safe alternative procedure in the treatment of the four-level CSM. 4.

Direct Posterior Bipolar Cervical Facet Radiofrequency Rhizotomy: A Simpler and Safer Approach to Denervate the Facet Capsule.

PubMed

Palea, Ovidiu; Andar, Haroon M; Lugo, Ramon; Granville, Michelle; Jacobson, Robert E

2018-03-14

Radiofrequency cervical rhizotomy has been shown to be effective for the relief of chronic neck pain, whether it be due to soft tissue injury, cervical spondylosis, or post-cervical spine surgery. The target and technique have traditionally been taught using an oblique approach to the anterior lateral capsule of the cervical facet joint. The goal is to position the electrode at the proximal location of the recurrent branch after it leaves the exiting nerve root and loops back to the cervical facet joint. The standard oblique approach to the recurrent nerve requires the testing of both motor and sensory components to verify the correct position and ensure safety so as to not damage the slightly more anterior nerve root. Bilateral lesions require the repositioning of the patient's neck. Poorly positioned electrodes can also pass anteriorly and contact the nerve root or vertebral artery. The direct posterior approach presented allows electrode positioning over a broader expanse of the facet joint without risk to the nerve root or vertebral artery. Over a four-year period, direct posterior radiofrequency ablation was performed under fluoroscopic guidance at multiple levels without neuro-stimulation testing with zero procedural neurologic events even as high as the C2 spinal segment. The direct posterior approach allows either unipolar or bipolar lesioning at multiple levels. Making a radiofrequency lesion along the larger posterior area of the facet capsule is as effective as the traditional target point closer to the nerve root but technically easier, allowing bilateral access and safety. The article will review the anatomy and innervation of the cervical facet joint and capsule, showing the diffuse nerve supply extending into the capsule of the facet joint that is more extensive than the recurrent medial sensory branches that have been the focus of radiofrequency lesioning.

Direct Posterior Bipolar Cervical Facet Radiofrequency Rhizotomy: A Simpler and Safer Approach to Denervate the Facet Capsule

PubMed Central

Palea, Ovidiu; Andar, Haroon M; Lugo, Ramon; Jacobson, Robert E

2018-01-01

Radiofrequency cervical rhizotomy has been shown to be effective for the relief of chronic neck pain, whether it be due to soft tissue injury, cervical spondylosis, or post-cervical spine surgery. The target and technique have traditionally been taught using an oblique approach to the anterior lateral capsule of the cervical facet joint. The goal is to position the electrode at the proximal location of the recurrent branch after it leaves the exiting nerve root and loops back to the cervical facet joint. The standard oblique approach to the recurrent nerve requires the testing of both motor and sensory components to verify the correct position and ensure safety so as to not damage the slightly more anterior nerve root. Bilateral lesions require the repositioning of the patient's neck. Poorly positioned electrodes can also pass anteriorly and contact the nerve root or vertebral artery. The direct posterior approach presented allows electrode positioning over a broader expanse of the facet joint without risk to the nerve root or vertebral artery. Over a four-year period, direct posterior radiofrequency ablation was performed under fluoroscopic guidance at multiple levels without neuro-stimulation testing with zero procedural neurologic events even as high as the C2 spinal segment. The direct posterior approach allows either unipolar or bipolar lesioning at multiple levels. Making a radiofrequency lesion along the larger posterior area of the facet capsule is as effective as the traditional target point closer to the nerve root but technically easier, allowing bilateral access and safety. The article will review the anatomy and innervation of the cervical facet joint and capsule, showing the diffuse nerve supply extending into the capsule of the facet joint that is more extensive than the recurrent medial sensory branches that have been the focus of radiofrequency lesioning. PMID:29765790

Feasibility and Biomechanics of Multilevel Arthroplasty and Combined Cervical Arthrodesis and Arthroplasty.

PubMed

Safavi-Abbasi, Sam; Reyes, Phillip M; Abjornson, Celeste; Crawford, Neil R

2016-12-01

A new experimental protocol was applied utilizing a simplified postural control model. Multiple constructs were tested nondestructively by interconnecting segmental rods to screws. To investigate how posture and distribution of segmental angles under physiological loads are affected by combined cervical arthroplasty and fusion. Previous studies of biomechanics of multilevel arthroplasty have focused on range of motion and intradiscal pressure. No previous study has investigated postural changes and segmental angle distribution. In 7 human cadaveric C3-T1 specimens, C4-C5, C5-C6, and C6-C7 disks were replaced with ProDisc-C (Synthes). Combinations of fusion (f) adjacent to arthroplasty (A) were simulated at C4-C5, C5-C6, and C6-C7, respectively: fAA, AfA, AAf, ffA, fAf, Aff, fff. C3-C4 and C7-T1 remained intact. A compressive belt apparatus simulated normal muscle cocontraction and gravitational preload; C3-C4, C4-C5, C5-C6, C6-C7, and C7-T1 motions were tracked independently. Parameters studied were segmental postural compensation, neutral buckling, and shift in sagittal plane instantaneous axis of rotation (IAR). With one or more levels unfused, the arthroplasty levels preferentially moved toward upright posture before the intact levels. Neutral buckling was greatest for 3-level arthroplasty, less for 2-level arthroplasty, and least for 1-level arthroplasty. Among the three 1-level arthroplasty groups (ffA, fAf, Aff), arthroplasty at the caudalmost level resulted in significantly greater buckling than with arthroplasty rostralmost or at mid-segment (P<0.04, analysis of variance/Holm-Sidak). Although IAR location was related to buckling, this correlation did not reach significance (P=0.112). Arthroplasty levels provide the "path of least resistance," through which the initial motion is more likely to occur. The tendency for specimens to buckle under vertical compression became greater with more arthroplasty levels. Buckling appeared more severe with arthroplasty more caudal. Buckling only moderately correlated to shifts in IAR, meaning slight malpositioning of the devices would not necessarily cause buckling.

This pineal gland does not mediate phase shifts in the disc shedding rhythm of the rat retina

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldman, A.I.

Albino rats were subjected to pinealectomy, superior cervical ganglionectomy, or the appropriate sham preparation and were placed in lighting conditions so that light onset was advanced by 10 hr. After 6 days of this regimen, all animals exhibited a complete shift in their outer segment disc shedding rhythm, indicating that the pineal gland is not a factor in mediating such a shift.

Detection of immunocytological markers in photomicroscopic images

NASA Astrophysics Data System (ADS)

Friedrich, David; zur Jacobsmühlen, Joschka; Braunschweig, Till; Bell, André; Chaisaowong, Kraisorn; Knüchel-Clarke, Ruth; Aach, Til

2012-03-01

Early detection of cervical cancer can be achieved through visual analysis of cell anomalies. The established PAP smear achieves a sensitivity of 50-90%, most false negative results are caused by mistakes in the preparation of the specimen or reader variability in the subjective, visual investigation. Since cervical cancer is caused by human papillomavirus (HPV), the detection of HPV-infected cells opens new perspectives for screening of precancerous abnormalities. Immunocytochemical preparation marks HPV-positive cells in brush smears of the cervix with high sensitivity and specificity. The goal of this work is the automated detection of all marker-positive cells in microscopic images of a sample slide stained with an immunocytochemical marker. A color separation technique is used to estimate the concentrations of the immunocytochemical marker stain as well as of the counterstain used to color the nuclei. Segmentation methods based on Otsu's threshold selection method and Mean Shift are adapted to the task of segmenting marker-positive cells and their nuclei. The best detection performance of single marker-positive cells was achieved with the adapted thresholding method with a sensitivity of 95.9%. The contours differed by a modified Hausdorff Distance (MHD) of 2.8 μm. Nuclei of single marker positive cells were detected with a sensitivity of 95.9% and MHD = 1.02 μm.

Improve definition of titanium tandems in MR-guided high dose rate brachytherapy for cervical cancer using proton density weighted MRI

PubMed Central

2013-01-01

Background For cervical cancer patients treated with MR-guided high dose rate brachytherapy, the accuracy of radiation delivery depends on accurate localization of both tumors and the applicator, e.g. tandem and ovoid. Standard T2-weighted (T2W) MRI has good tumor-tissue contrast. However, it suffers from poor uterus-tandem contrast, which makes the tandem delineation very challenging. In this study, we evaluated the possibility of using proton density weighted (PDW) MRI to improve the definition of titanium tandems. Methods Both T2W and PDW MRI images were obtained from each cervical cancer patient. Imaging parameters were kept the same between the T2W and PDW sequences for each patient except the echo time (90 ms for T2W and 5.5 ms for PDW) and the slice thickness (0.5 cm for T2W and 0.25 cm for PDW). Uterus-tandem contrast was calculated by the equation C = (Su-St)/Su, where Su and St represented the average signal in the uterus and the tandem, respectively. The diameter of the tandem was measured 1.5 cm away from the tip of the tandem. The tandem was segmented by the histogram thresholding technique. Results PDW MRI could significantly improve the uterus-tandem contrast compared to T2W MRI (0.42±0.24 for T2W MRI, 0.77±0.14 for PDW MRI, p=0.0002). The average difference between the measured and physical diameters of the tandem was reduced from 0.20±0.15 cm by using T2W MRI to 0.10±0.11 cm by using PDW MRI (p=0.0003). The tandem segmented from the PDW image looked more uniform and complete compared to that from the T2W image. Conclusions Compared to the standard T2W MRI, PDW MRI has better uterus-tandem contrast. The information provided by PDW MRI is complementary to those provided by T2W MRI. Therefore, we recommend adding PDW MRI to the simulation protocol to assist tandem delineation process for cervical cancer patients. PMID:23327682

An in vivo comparison study in goats for a novel motion-preserving cervical joint system

PubMed Central

Qin, Jie; Zhao, Chenguang; Wang, Dong; Zhao, Bo; Dong, Jun; Li, Haopeng; Sang, Rongxia; Wang, Shuang; Fu, Jiao; Kong, Rangrang

2017-01-01

Cervical degenerative disease is one of the most common spinal disorders worldwide, especially in older people. Anterior cervical corpectomy and fusion (ACCF) is a useful method for the surgical treatment of multi-level cervical degenerative disease. Anterior cervical disc replacement (ACDR) is considered as an alternative surgical method. However, both methods have drawbacks, particularly the neck motion decrease observed after arthrodesis, and arthroplasty should only be performed on patients presenting with cervical disc disease but without any vertebral body disease. Therefore, we designed a non-fusion cervical joint system, namely an artificial cervical vertebra and intervertebral complex (ACVC), to provide a novel treatment for multi-level cervical degenerative disease. To enhance the long-term stability of ACVC, we applied a hydroxyapatite (HA) biocoating on the surface of the artificial joint. Thirty-two goats were randomly divided into four groups: a sham control group, an ACVC group, an ACVC-HA group, and an ACCF group (titanium and plate fixation group). We performed the prosthesis implantation in our previously established goat model. We compared the clinical, radiological, biomechanical, and histological outcomes among these four different groups for 24 weeks post surgery. The goats successfully tolerated the entire experimental procedure. The kinematics data for the ACVC and ACVC-HA groups were similar. The range of motion (ROM) in adjacent level increased after ACCF but was not altered after ACVC or ACVC-HA implantation. Compared with the control group, no significant difference was found in ROM and neutral zone (NZ) in flexion-extension or lateral bending for the ACVC and ACVC-HA groups, whereas the ROM and NZ in rotation were significantly greater. Compared with the ACCF group, the ROM and NZ significantly increased in all directions. Overall, stiffness was significantly decreased in the ACVC and ACVC-HA groups compared with the control group and the ACCF group. Similar results were found after a fatigue test of 5,000 repetitions of axial rotation. The histological results showed more new bone formation and better bone implant contact in the ACVC-HA group than the ACVC group. Goat is an excellent animal model for cervical spine biomechanical study. Compared with the intact state and the ACCF group, ACVC could provide immediate stability and preserve segmental movement after discectomy and corpectomy. Besides, HA biocoating provide a better bone ingrowth, which is essential for long-term stability. In conclusion, ACVC-HA brings new insight to treat cervical degenerative disease. PMID:28582418

Frequency and Acceptability of Adverse Events After Anterior Cervical Discectomy and Fusion: A Survey Study From the Cervical Spine Research Society.

PubMed

Wilson, Jefferson R; Radcliff, Kris; Schroeder, Gregory; Booth, Madison; Lucasti, Christopher; Fehlings, Michael; Ahmad, Nassr; Vaccaro, Alexander; Arnold, Paul; Sciubba, Daniel; Ching, Alex; Smith, Justin; Shaffrey, Christopher; Singh, Kern; Darden, Bruce; Daffner, Scott; Cheng, Ivan; Ghogawala, Zoher; Ludwig, Steven; Buchowski, Jacob; Brodke, Darrel; Wang, Jeffrey; Lehman, Ronald A; Hilibrand, Alan; Yoon, Tim; Grauer, Jonathan; Dailey, Andrew; Steinmetz, Michael; Harrop, James S

2018-06-01

Anterior cervical discectomy and fusion has a low but well-established profile of adverse events. The goal of this study was to gauge surgeon opinion regarding the frequency and acceptability of these events. A 2-page survey was distributed to attendees at the 2015 Cervical Spine Research Society (CSRS) meeting. Respondents were asked to categorize 18 anterior cervical discectomy and fusion-related adverse events as either: "common and acceptable," "uncommon and acceptable," "uncommon and sometimes acceptable," or "uncommon and unacceptable." Results were compiled to generate the relative frequency of these responses for each complication. Responses for each complication event were also compared between respondents based on practice location (US vs. non-US), primary specialty (orthopedics vs. neurosurgery) and years in practice. Of 150 surveys distributed, 115 responses were received (76.7% response rate), with the majority of respondents found to be US-based (71.3%) orthopedic surgeons (82.6%). Wrong level surgery, esophageal injury, retained drain, and spinal cord injury were considered by most to be unacceptable and uncommon complications. Dysphagia and adjacent segment disease occurred most often, but were deemed acceptable complications. Although surgeon experience and primary specialty had little impact on responses, practice location was found to significantly influence responses for 12 of 18 complications, with non-US surgeons found to categorize events more toward the uncommon and unacceptable end of the spectrum as compared with US surgeons. These results serve to aid communication and transparency within the field of spine surgery, and will help to inform future quality improvement and best practice initiatives.

A Novel Technique for Cervical Facet Joint Hyperplasia-Spondylotic Radiculopathy by Laminar and Lateral Mass Screw Cofixations.

PubMed

Sheng, Sun-Ren; Wang, Ke; Nisar, Majid; Chen, Jiao-Xiang; Wu, Ai-Min; Wang, Xiang-Yang

2018-02-01

We sought to describe the novel technique and report the outcomes of cervical spondylotic radiculopathy caused by facet joint hyperplasia treated with minimally invasive surgery by laminar and lateral mass screw cofixations. In this retrospective study, patients with spondylotic radiculopathy caused by facet joint hyperplasia underwent this technique in our unit between January 2010 and June 2015. Hospital charts, magnetic resonance imaging studies, and follow-up records for all the patients were reviewed. Outcomes were assessed on the basis of neurologic status, magnetic resonance imaging, and visual analog scale for neck and radicular pain and by the short form-36 health survey questionnaire. Thirteen men and 5 women, aged 47-73 years (mean, 61.8 years), were included in this study. The follow-up time ranged from 19-50 months (mean, 32.4 months). The mean visual analog scale scores for radicular pain and neck pain, as well as the scores for all 8 domains of the short form-36 health survey questionnaire, showed significant improvements (P < 0.05). Cervical lordosis showed bending, whereas the height of the targeted disk segment showed no change (P > 0.05). Complications included 2 cases of neck pain that lasted for 3 months. Minimally invasive surgery by lamina and lateral mass screw cofixation is safe and effective for the treatment of cervical spondylotic radiculopathy caused by facet joint hyperplasia. In addition to sufficient decompression, this technique provides relative stability to the cervical spine. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Therapeutic intraspinal microstimulation improves forelimb function after cervical contusion injury

NASA Astrophysics Data System (ADS)

Kasten, M. R.; Sunshine, M. D.; Secrist, E. S.; Horner, P. J.; Moritz, C. T.

2013-08-01

Objective. Intraspinal microstimulation (ISMS) is a promising method for activating the spinal cord distal to an injury. The objectives of this study were to examine the ability of chronically implanted stimulating wires within the cervical spinal cord to (1) directly produce forelimb movements, and (2) assess whether ISMS stimulation could improve subsequent volitional control of paretic extremities following injury. Approach. We developed a technique for implanting intraspinal stimulating electrodes within the cervical spinal cord segments C6-T1 of Long-Evans rats. Beginning 4 weeks after a severe cervical contusion injury at C4-C5, animals in the treatment condition received therapeutic ISMS 7 hours/day, 5 days/week for the following 12 weeks. Main results. Over 12 weeks of therapeutic ISMS, stimulus-evoked forelimb movements were relatively stable. We also explored whether therapeutic ISMS promoted recovery of forelimb reaching movements. Animals receiving daily therapeutic ISMS performed significantly better than unstimulated animals during behavioural tests conducted without stimulation. Quantitative video analysis of forelimb movements showed that stimulated animals performed better in the movements reinforced by stimulation, including extending the elbow to advance the forelimb and opening the digits. While threshold current to elicit forelimb movement gradually increased over time, no differences were observed between chronically stimulated and unstimulated electrodes suggesting that no additional tissue damage was produced by the electrical stimulation. Significance. The results indicate that therapeutic intraspinal stimulation delivered via chronic microwire implants within the cervical spinal cord confers benefits extending beyond the period of stimulation, suggesting future strategies for neural devices to promote sustained recovery after injury.

Voxel-wise mapping of cervical cord damage in multiple sclerosis patients with different clinical phenotypes.

PubMed

Rocca, Maria A; Valsasina, Paola; Damjanovic, Dusan; Horsfield, Mark A; Mesaros, Sarlota; Stosic-Opincal, Tatjana; Drulovic, Jelena; Filippi, Massimo

2013-01-01

To apply voxel-based methods to map the regional distribution of atrophy and T2 hyperintense lesions in the cervical cord of multiple sclerosis (MS) patients with different clinical phenotypes. Brain and cervical cord 3D T1-weighted and T2-weighted scans were acquired from 31 healthy controls (HC) and 77 MS patients (15 clinically isolated syndromes (CIS), 15 relapsing-remitting (RR), 19 benign (B), 15 primary progressive (PP) and 13 secondary progressive (SP) MS). Hyperintense cord lesions were outlined on T2-weighted scans. The T2- and 3D T1-weighted cord images were then analysed using an active surface method which created output images reformatted in planes perpendicular to the estimated cord centre line. These unfolded cervical cord images were co-registered into a common space; then smoothed binary cord masks and lesion masks underwent spatial statistic analysis (SPM8). No cord atrophy was found in CIS patients versus HC, while PPMS had significant cord atrophy. Clusters of cord atrophy were found in BMS versus RRMS, and in SPMS versus RRMS, BMS and PPMS patients, mainly involving the posterior and lateral cord segments. Cord lesion probability maps showed a significantly greater likelihood of abnormalities in RRMS, PPMS and SPMS than in CIS and BMS patients. The spatial distributions of cord atrophy and cord lesions were not correlated. In progressive MS, regional cord atrophy was correlated with clinical disability and impairment in the pyramidal system. Voxel-based assessment of cervical cord damage is feasible and may contribute to a better characterisation of the clinical heterogeneity of MS patients.

Therapeutic intraspinal microstimulation improves forelimb function after cervical contusion injury

PubMed Central

Kasten, M.R.; Sunshine, M.D.; Secrist, E.S.; Horner, P.J.; Moritz, C.T.

2013-01-01

Objective Intraspinal microstimulation (ISMS) is a promising method for activating the spinal cord distal to an injury. The objectives of this study were to examine the ability of chronically implanted stimulating wires within the cervical spinal cord to (1) directly produce forelimb movements, and (2) assess whether ISMS stimulation improved subsequent volitional control of paretic extremities following injury. Approach We developed a technique for implanting intraspinal stimulating electrodes within the cervical spinal cord segments C6-T1 of Long-Evans rats. Beginning 4 weeks after a severe cervical contusion injury at C4–C5, animals in the treatment condition received therapeutic ISMS 7 hours/day, 5 days/week for the following 12 weeks. Main Results Over 12 weeks of therapeutic ISMS, stimulus-evoked forelimb movements were relatively stable. We also explored whether therapeutic ISMS promotes recovery of forelimb reaching movements. Animals receiving daily therapeutic ISMS performed significantly better than unstimulated animals during behavioral tests conducted without stimulation. Quantitative video analysis of forelimb movements showed that stimulated animals performed better in the movements reinforced by stimulation, including extending the elbow to advance the forelimb and opening the digits. While threshold current to elicit forelimb movement gradually increased over time, no differences were observed between chronically stimulated and unstimulated electrodes suggesting that no additional tissue damage was produced by the electrical stimulation. Significance The results indicate that therapeutic intraspinal stimulation delivered via chronic microwire implants within the cervical spinal cord confers benefits extending beyond the period of stimulation, suggesting future strategies for neural devices to promote sustained recovery after injury. PMID:23715242

Emergency removal of football equipment: a cadaveric cervical spine injury model.

PubMed

Gastel, J A; Palumbo, M A; Hulstyn, M J; Fadale, P D; Lucas, P

1998-10-01

To determine the influence of football helmet and shoulder pads, alone or in combination, on alignment of the unstable cervical spine. The alignment of the intact cervical spine in 8 cadavers was assessed radiographically under 4 different football equipment conditions: (1) no equipment, (2) helmet only, (3) helmet and shoulder pads, and (4) shoulder pads only. Each specimen was then surgically destabilized at C5-C6 to simulate a flexion-distraction injury. Repeat radiographs were obtained under the same 4 equipment conditions, and alignment of the unstable segment was analyzed. Before the destabilization, neutral alignment was maintained when both helmet and shoulder pads were in place. The "helmet only" condition caused a significant decrease in lordosis (mean, 9.6 +/- 4.7 degrees), whereas the "shoulder pads only" condition caused increased lordosis (13.6 +/- 6.3 degrees). After destabilization, the "helmet-only" condition demonstrated significant mean increases in C5-C6 forward angulation (16.5 +/- 8.6 degrees), posterior disc space height (3.8 +/- 2.3 mm), and dorsal element distraction (8.3 +/- 5.4 mm). Our flexion-distraction model demonstrated that immobilization of the neck-injured football player with only the helmet in place violates the principle of splinting the cervical spine in neutral alignment. By extrapolation to an extension-type injury, immobilization with only the shoulder pads left in place similarly violates this principle. In order to maintain a neutral position and minimize secondary injury to the cervical neural elements, the helmet and shoulder pads should be either both left on or both removed in the emergency setting.

Airway management of patients with traumatic brain injury/C-spine injury

PubMed Central

2015-01-01

Traumatic brain injury (TBI) is usually combined with cervical spine (C-spine) injury. The possibility of C-spine injury is always considered when performing endotracheal intubation in these patients. Rapid sequence intubation is recommended with adequate sedative or analgesics and a muscle relaxant to prevent an increase in intracranial pressure during intubation in TBI patients. Normocapnia and mild hyperoxemia should be maintained to prevent secondary brain injury. The manual-in-line-stabilization (MILS) technique effectively lessens C-spine movement during intubation. However, the MILS technique can reduce mouth opening and lead to a poor laryngoscopic view. The newly introduced video laryngoscope can manage these problems. The AirWay Scope® (AWS) and AirTraq laryngoscope decreased the extension movement of C-spines at the occiput-C1 and C2-C4 levels, improving intubation conditions and shortening the time to complete tracheal intubation compared with a direct laryngoscope. The Glidescope® also decreased cervical movement in the C2-C5 levels during intubation and improved vocal cord visualization, but a longer duration was required to complete intubation compared with other devices. A lightwand also reduced cervical motion across all segments. A fiberoptic bronchoscope-guided nasal intubation is the best method to reduce cervical movement, but a skilled operator is required. In conclusion, a video laryngoscope assists airway management in TBI patients with C-spine injury. PMID:26045922

Influence of abutment design on the success of immediately loaded dental implants: experimental and numerical studies.

PubMed

Hasan, I; Röger, B; Heinemann, F; Keilig, L; Bourauel, C

2012-09-01

The aim of the present study was to investigate experimentally and numerically the influence of a fine threaded- against a roughened-cervical region of immediately loaded dental implants in combination with straight and 20°-angled abutments on the implant primary stability. A total of 30 implants were inserted in bovine rib-segments, 14 cervically roughened implants and 16 implants with fine cervical threads. Each implant system received two abutments, straight and 20°-angled. Implant displacements and rotations were measured using a biomechanical measurement system. Subsequently, eight samples were selected for geometrical reconstruction and numerical investigation of stress and strain distributions in the bone by means of the finite element method. Experimentally, both implant systems showed similar behaviour with the straight abutments concerning displacements and rotations. However, fine threaded implants showed much less displacement and rotation against roughened implants when angled abutments were considered. Numerically, stresses were within 35-45 MPa in the cortical bone for both implant systems. The strains showed highest values within the spongious bone with the roughened implants connected to angled abutments. The results indicate that implants with fine cervical threads could be recommended in particular with angled abutments. The outcomes of this study are currently confirmed by long-term clinical investigations. Copyright © 2011 IPEM. Published by Elsevier Ltd. All rights reserved.

Neonatal C1 TO C2 osteomyelitis leading to instability and neurological decline: novel treatment with occiput-C1-C2 fusion and occiput to thorax growing rods. A case report.

PubMed

Glotzbecker, Michael P; Wasser, Aubrey M; Troy, Michael J; Proctor, Mark; Emans, John B

2015-06-01

Vertebral osteomyelitis of the upper cervical spine requiring surgical treatment in children is rare. Surgical treatment of the immature spine is commonly associated with certain risks and complications. We describe a unique treatment approach for a young child that required emergent stabilization of the upper cervical spine due to progressive instability caused by osteomyelitis. A 3-month-old infant with neurological decline from progressive instability of the occiput C1 and C2 was admitted for surgical treatment after failed bracing. The patient had reduction and occiput to C2 posterior fusion and segmental instrumentation, with nonsegmental instrumentation extending in the soft tissues from C2 to T4 with the intent of providing stabilization without fusion and permitting further growth. The implants were removed 1 year after the original procedure. At 2 years following implant removal, he continued to have mild global developmental delay but was progressing well and was able to navigate independently with a posterior walker, using AFOs for support. Subaxial cervical motion and x-ray appearance were normal. The technique used here to overcome the difficulty of providing secure immobilization of the craniocervical junction while not creating inadvertent fusion of the subaxial cervical spine may have application in other clinical situations. Level V.

[The biomechanics of hyperextension injuries of the subaxial cervical spine].

PubMed

Stein, G; Meyer, C; Ingenhoff, L; Bredow, J; Müller, L P; Eysel, P; Schiffer, G

2017-07-01

Hyperextension injuries of the subaxial cervical spine are potentially hazardous due to relevant destabilization. Depending on the clinical condition, neurologic or vascular damage may occur. Therefore an exact knowledge of the factors leading to destabilization is essential. In a biomechanical investigation, 10 fresh human cadaver cervical spine specimens were tested in a spine simulator. The tested segments were C4 to 7. In the first step, physiologic motion was investigated. Afterwards, the three steps of injury were dissection of the anterior longitudinal ligament, removal of the intervertebral disc/posterior longitudinal ligament, and dissection of the interspinous ligaments/ligamentum flavum. After each step, the mobility was determined. Regarding flexion and extension, an increase in motion of 8.36 % after the first step, 90.45 % after the second step, and 121.67 % after the last step was observed. Testing of lateral bending showed an increase of mobility of 7.88 %/27.48 %/33.23 %; axial rotation increased by 2.87 %/31.16 %/45.80 %. Isolated dissection of the anterior longitudinal ligament led to minor destabilization, whereas the intervertebral disc has to be seen as a major stabilizer of the cervical spine. Few finite-element studies showed comparable results. If a transfer to clinical use is undertaken, an isolated rupture of the anterior longitudinal ligament can be treated without surgical stabilization.

In vitro biomechanical comparison of multistrand cables with conventional cervical stabilization.

PubMed

Weis, J C; Cunningham, B W; Kanayama, M; Parker, L; McAfee, P C

1996-09-15

The biomechanical stability of six different methods of cervical spine stabilization, three using multistrand cables, were evaluated in a bovine model. To quantify and compare the in vitro biomechanical properties of multistrand cables used for posterior cervical wiring to standard cervical fixation techniques. Fixation of the posterior cervical spine with monofilament stainless steel wire is a proven technique for stabilization of the cervical spine. Recently, multistrand braided cables have been used as a substitute for monofilament stainless steel wires. These cables, made of stainless steel, titanium, or polyethylene, are reported to be stronger, more flexible, and fatigue resistant than are monofilament wire based on mechanical testing. However, no in vitro biomechanical studies have been performed testing a standard posterior cervical wiring technique using multistrand cables. Thirty-six fresh frozen cervical calf spines consistent in size and age were mounted and fixed rigidly to isolate the C4-C5 motion segment. Six different reconstruction techniques were evaluated for Rogers' posterior cervical wiring technique using: 1) 20-gauge stainless steel monofilament wire, 2) stainless steel cable, 3) titanium cable, 4) polyethylene cables, 5) anterior locking plate construct with interbody graft, and 6) posterior plate construct. Six cervical spines were included in each group (n = 6), with each specimen statically evaluated under three stability conditions: 1) intact, 2) reconstructed, and 3) postfatigue. The instability model created before the reconstruction consisted of a distractive flexion Stage 3 injury at C4-C5. Nondestructive static biomechanical testing, performed on an material testing machine (MTS 858 Bionix test system, Minneapolis, MN), included axial compression, axial rotation, flexion-extension, and lateral bending. After reconstruction and static analysis, the specimens were fatigued for 1500 cycles and then statically retested. Data analysis included normalization of the reconstructed and postfatigue data to the intact condition. The calculated static parameters included operative functional unit stiffness and range of motion. Posterior cervical reconstruction with stainless steel monofilament wire proved inadequate under fatigue testing. Two of the six specimens failed with fatigue, and this construct permitted the greatest degree of flexion-extension motion after fatigue in comparison with all other constructs (P < 0.05). There were no significant differences in flexural stiffness or range of motion between stainless steel, titanium, or polyethylene cable constructs before or after fatigue testing. The posterior cervical plate constructs were the stiffest constructs under flexion, extension, and lateral bending modes, before and after fatigue testing (P < 0.05). Multistrand cables were superior to monofilament wire with fatigue testing using an in vitro calf cervical spine model. There were no failures or detectable differences in elongation after fatigue testing between the stainless steel, titanium, and polyethylene cables, as shown by the flexion-extension range of motion. The posterior cervical plate construct offered the greatest stability compared with all other constructs.

Original treatment for ischaemic stenosis of colon interposition: Report of two cases.

PubMed

Daldoul, S; Moussi, A; Sayari, S; Ben Moussa, M

2017-02-01

The treatment of ischaemic stenosis of colon interposition for oesophageal replacement remains poorly defined. We report two cases of patients operated for ischaemic stenosis of the cervical extremity of the colon interposition for caustic stenosis of the oesophagus. Treatment consisted of resection of the stenosis with creation of a new cervical anastomosis after complete release of the colon graft via a neck and upper midline incision in one patient and a new ileocolic graft exclusively replacing the stenotic segment of the oesophagoplasty in the second patient. These two cases illustrate the complex treatment modalities required for this complication. The treatment of choice of ischaemic stenosis of colon interposition is resection with creation of a new anastomosis, but repeat graft may sometimes be the only available treatment option. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Tracheal reconstruction with autogenous jejunal microsurgical transfer.

PubMed

Jones, R E; Morgan, R F; Marcella, K L; Mills, S E; Kron, I L

1986-06-01

Tracheal defects due to stricture formation, tracheomalacia, and neoplasms can present difficult reconstructive problems. Tracheal defects were surgically created in 6 dogs and primarily reconstructed with microsurgical free tissue transfer of autogenous jejunal segments. Primary healing was accomplished in all dogs without severe air leakage or infection. Bronchoscopy demonstrated no substantial secretions or tracheal narrowing. Gross pathological examination of the trachea revealed no evidence of tracheal disruption or infection. Direct measurements revealed no major tracheal narrowing. Microscopic examination demonstrated normal jejunal mucosa with a minimal amount of inflammatory change at the margins of the reconstruction at 6 weeks. Microvascular free tissue transfer of jejunal segments to correct cervical tracheal defects can readily be accomplished with excellent healing and maintenance of the tracheal lumen in dogs.

Ultrasound guided V3 segment vertebral artery direct percutaneous puncture for basilar artery mechanical thrombectomy in acute stroke: a technical report.

PubMed

Desai, Jamsheed A; Almekhlafi, Mohammed A; Hill, Michael D; Goyal, Mayank; Eesa, Muneer

2014-04-01

A middle aged patient presented with acute ischemic stroke due to basilar artery occlusion. The patient clinically deteriorated despite intravenous thrombolysis and was referred for mechanical thrombectomy. The right vertebral artery was occluded and could not be accessed despite attempting various shaped catheters, even when a radial artery access was used. The left vertebral artery ended in the posterior inferior cerebellar artery. Eventually, ultrasound guided V3 segment vertebral artery direct puncture was successfully done and the procedure was completed. No access related complications were encountered. Direct cervical arterial puncture can be safely used by experienced operators as a last resort in acute stroke cases with difficult access.

Sampling the Uppermost Surface of Airless Bodies

NASA Technical Reports Server (NTRS)

Noble, S. K.; Keller, L. P.; Christoffersen, R.

2011-01-01

The uppermost surface of an airless body is a critical source of ground-truth information for the various remote sensing techniques that only penetrate nanometers to micrometers into the surface. Such samples will also be vital for understanding conditions at the surface and acquiring information about how the body interacts with its environment, including solar wind interaction, grain charging and levitation [1]. Sampling the uppermost surface while preserving its structure (e.g. porosity, grain-to-grain contacts) however, is a daunting task that has not been achieved on any sample return mission to date.

Localization and pattern of graviresponse across the pulvinus of barley Hordeum vulgare

NASA Technical Reports Server (NTRS)

Brock, T. G.; Lu, C. R.; Ghosheh, N. S.; Kaufman, P. B.

1989-01-01

Pulvini of excised stem segments from barley (Hordeum vulgare cv Larker') were pretreated with 1 millimolar coumarin before gravistimulation to reduce longitudinal cell expansion and exaggerate radial cell enlargement. The cellular localization and pattern of graviresponse across individual pulvini were then evaluated by cutting the organ in cross-section, photographing the cross-section, and then measuring pulvinus thickness and the radial width of cortical and epidermal cells in enlargements of the photomicrographs. With respect to orientation during gravistimulation, we designated the uppermost point of the cross-section 0 degrees and the lowermost point 180 degrees. A gravity-induced increase in pulvinus thickness was observable within 40 degrees of the vertical in coumarin-treated pulvini. In upper halves of coumarin-treated gravistimulated pulvini, cells in the inner cortex and inner epidermis had increased radial widths, relative to untreated gravistimulated pulvini. In lower halves of coumarin-treated pulvini, cells in the central and outer cortex and in the outer epidermis showed the greatest increase in radial width. Cells comprising the vascular bundles also increased in radial width, with this pattern following that of the central cortex. These results indicate (a) that all cell types are capable of showing a graviresponse, (b) that the graviresponse occurs in both the top and the bottom of the responding organ, and (c) that the magnitude of the response increases approximately linearly from the uppermost point to the lowermost. These results are also consistent with models of gravitropism that link the pattern and magnitude of the graviresponse to graviperception via statolith sedimentation.

Foliar application with nano-silicon reduced cadmium accumulation in grains by inhibiting cadmium translocation in rice plants.

PubMed

Chen, Rui; Zhang, Changbo; Zhao, Yanling; Huang, Yongchun; Liu, Zhongqi

2018-01-01

Nano-silicon (Si) may be more effective than regular fertilizers in protecting plants from cadmium (Cd) stress. A field experiment was conducted to study the effects of nano-Si on Cd accumulation in grains and other organs of rice plants (Oryza sativa L. cv. Xiangzaoxian 45) grown in Cd-contaminated farmland. Foliar application with 5~25 mM nano-Si at anthesis stage reduced Cd concentrations in grains and rachises at maturity stage by 31.6~64.9 and 36.1~60.8%, respectively. Meanwhile, nano-Si application significantly increased concentrations of potassium (K), magnesium (Mg), and iron (Fe) in grains and rachises, but imposed little effect on concentrations of calcium (Ca), zinc (Zn), and manganese (Mn) in them. Uppermost nodes under panicles displayed much higher Cd concentration (4.50~5.53 mg kg -1 ) than other aerial organs. After foliar application with nano-Si, translocation factors (TFs) of Cd ions from the uppermost nodes to rachises significantly declined, but TFs of K, Mg, and Fe from the uppermost nodes to rachises increased significantly. High dose of nano-Si (25 mM) was more effective than low dose of nano-Si in reducing TFs of Cd from roots to the uppermost nodes and from the uppermost nodes to rachises. These findings indicate that nano-Si supply reduces Cd accumulation in grains by inhibiting translocation of Cd and, meanwhile, promoting translocation of K, Mg, and Fe from the uppermost nodes to rachises in rice plants.

[Rotational mobility of the schoolchildren's vertebral column as a criterion for evaluating its functional status].

PubMed

Akopian, E S; Ter-Marganian, N G

2009-01-01

As known, all movements in the vertebral column are effected in the perpendicular planes and its training is required in all directions. Rotational movements make it possible to activate fixed spinal (thoracic, sacral) mobility, to improve their trophism and innervation and aid to interact all the spinal segments as an integral train. That is the reason why studying the rotational mobility of the vertebral column in children of school age is critically important. The algorithm developed and tested in practice was used to evaluate rotational mobility of the vertebral column (its movement about its axis) in the cervical and lumbar portions. The results of examining the rotational mobility of the cervical portion, which are fixed in all age groups, suggest that it is this spinal portion that is the most vulnerable, sensitive link that is rapidly responsive to its inadequate movements. All the above lends support to the necessity of making the special training of the cervical spine. The results of a pedagogical experiment have allowed the authors to be the first in physical educational practice to develop regional standard scales used to evaluate spinal rotational mobility in schoolchildren.

A new multipartite plate system for anterior cervical spine surgery; finite element analysis.

PubMed

Şimşek, Hakan; Zorlu, Emre; Kaya, Serdar; Baydoğan, Murat; Atabey, Cem; Çolak, Ahmet

2017-12-19

There are numerous available plates, almost all of which are compact one-piece plates. During the placement of relatively long plates in the treatment of multi-level cervical pathologies, instrument related complications might appear. In order to overcome this potential problem, a novel 'articulated plate system' is designed. We aimed to delineate finite element analysis and mechanical evaluations. A new plate system consisting of multi partite structure for anterior cervical stabilization was designed. Segmental plates were designed for application onto the ventral surface of the vertebral body. Plates differed from 9 to13 mm in length. There are rods at one end and hooks at the other end. Terminal points consisted of either hooks or rods at one end but the other ends are blind. Finite element and mechanical tests of the construct were performed applying bending, axial loading, and distraction forces. Finite element and mechanical testing results yielded the cut off values for functional failure and breakage of the system. The articulated system proved to be mechanically safe and it lets extension of the system on either side as needed. Ease of application needs further verification via a cadaveric study.

Meta-Analysis Comparing Zero-Profile Spacer and Anterior Plate in Anterior Cervical Fusion.

PubMed

Dong, Jun; Lu, Meng; Lu, Teng; Liang, Baobao; Xu, Junkui; Zhou, Jun; Lv, Hongjun; Qin, Jie; Cai, Xuan; Huang, Sihua; Li, Haopeng; Wang, Dong; He, Xijing

2015-01-01

Anterior plate fusion is an effective procedure for the treatment of cervical spinal diseases but is accompanied by a high incidence of postoperative dysphagia. A zero profile (Zero-P) spacer is increasingly being used to reduce postoperative dysphagia and other potential complications associated with surgical intervention. Studies comparing the Zero-P spacer and anterior plate have reported conflicting results. A meta-analysis was conducted to compare the safety, efficacy, radiological outcomes and complications associated with the use of a Zero-P spacer versus an anterior plate in anterior cervical spine fusion for the treatment of cervical spinal disease. We comprehensively searched PubMed, Embase, the Cochrane Library and other databases and performed a meta-analysis of all randomized controlled trials (RCTs) and prospective or retrospective comparative studies assessing the two techniques. Ten studies enrolling 719 cervical spondylosis patients were included. The pooled data showed significant differences in the operation time [SMD = -0.58 (95% CI = -0.77 to 0.40, p < 0.01)] and blood loss [SMD = -0.40, 95% CI (-0.59 to -0.21), p < 0.01] between the two groups. Compared to the anterior plate group, the Zero-P group exhibited a significantly improved JOA score and reduced NDI and VAS. However, anterior plate fusion had greater postoperative segmental and cervical Cobb's angles than the Zero-P group at the last follow-up. The fusion rate in the two groups was similar. More importantly, the Zero-P group had a lower incidence of earlier and later postoperative dysphagia. Compared to anterior plate fusion, Zero-P is a safer and effective procedure, with a similar fusion rate and lower incidence of earlier and later postoperative dysphagia. However, the results of this meta-analysis should be accepted with caution due to the limitations of the study. Further evaluation and large-sample RCTs are required to confirm and update the results of this study.

A semi-automatic computer-aided method for surgical template design

NASA Astrophysics Data System (ADS)

Chen, Xiaojun; Xu, Lu; Yang, Yue; Egger, Jan

2016-02-01

This paper presents a generalized integrated framework of semi-automatic surgical template design. Several algorithms were implemented including the mesh segmentation, offset surface generation, collision detection, ruled surface generation, etc., and a special software named TemDesigner was developed. With a simple user interface, a customized template can be semi- automatically designed according to the preoperative plan. Firstly, mesh segmentation with signed scalar of vertex is utilized to partition the inner surface from the input surface mesh based on the indicated point loop. Then, the offset surface of the inner surface is obtained through contouring the distance field of the inner surface, and segmented to generate the outer surface. Ruled surface is employed to connect inner and outer surfaces. Finally, drilling tubes are generated according to the preoperative plan through collision detection and merging. It has been applied to the template design for various kinds of surgeries, including oral implantology, cervical pedicle screw insertion, iliosacral screw insertion and osteotomy, demonstrating the efficiency, functionality and generality of our method.

A semi-automatic computer-aided method for surgical template design

PubMed Central

Chen, Xiaojun; Xu, Lu; Yang, Yue; Egger, Jan

2016-01-01

This paper presents a generalized integrated framework of semi-automatic surgical template design. Several algorithms were implemented including the mesh segmentation, offset surface generation, collision detection, ruled surface generation, etc., and a special software named TemDesigner was developed. With a simple user interface, a customized template can be semi- automatically designed according to the preoperative plan. Firstly, mesh segmentation with signed scalar of vertex is utilized to partition the inner surface from the input surface mesh based on the indicated point loop. Then, the offset surface of the inner surface is obtained through contouring the distance field of the inner surface, and segmented to generate the outer surface. Ruled surface is employed to connect inner and outer surfaces. Finally, drilling tubes are generated according to the preoperative plan through collision detection and merging. It has been applied to the template design for various kinds of surgeries, including oral implantology, cervical pedicle screw insertion, iliosacral screw insertion and osteotomy, demonstrating the efficiency, functionality and generality of our method. PMID:26843434

A semi-automatic computer-aided method for surgical template design.

PubMed

Chen, Xiaojun; Xu, Lu; Yang, Yue; Egger, Jan

2016-02-04

This paper presents a generalized integrated framework of semi-automatic surgical template design. Several algorithms were implemented including the mesh segmentation, offset surface generation, collision detection, ruled surface generation, etc., and a special software named TemDesigner was developed. With a simple user interface, a customized template can be semi- automatically designed according to the preoperative plan. Firstly, mesh segmentation with signed scalar of vertex is utilized to partition the inner surface from the input surface mesh based on the indicated point loop. Then, the offset surface of the inner surface is obtained through contouring the distance field of the inner surface, and segmented to generate the outer surface. Ruled surface is employed to connect inner and outer surfaces. Finally, drilling tubes are generated according to the preoperative plan through collision detection and merging. It has been applied to the template design for various kinds of surgeries, including oral implantology, cervical pedicle screw insertion, iliosacral screw insertion and osteotomy, demonstrating the efficiency, functionality and generality of our method.

Toward an endovascular internal carotid artery classification system.

PubMed

Shapiro, M; Becske, T; Riina, H A; Raz, E; Zumofen, D; Jafar, J J; Huang, P P; Nelson, P K

2014-02-01

Does the world need another ICA classification scheme? We believe so. The purpose of proposed angiography-driven classification is to optimize description of the carotid artery from the endovascular perspective. A review of existing, predominantly surgically-driven classifications is performed, and a new scheme, based on the study of NYU aneurysm angiographic and cross-sectional databases is proposed. Seven segments - cervical, petrous, cavernous, paraophthlamic, posterior communicating, choroidal, and terminus - are named. This nomenclature recognizes intrinsic uncertainty in precise angiographic and cross-sectional localization of aneurysms adjacent to the dural rings, regarding all lesions distal to the cavernous segment as potentially intradural. Rather than subdividing various transitional, ophthalmic, and hypophyseal aneurysm subtypes, as necessitated by their varied surgical approaches and risks, the proposed classification emphasizes their common endovascular treatment features, while recognizing that many complex, trans-segmental, and fusiform aneurysms not readily classifiable into presently available, saccular aneurysm-driven schemes, are being increasingly addressed by endovascular means. We believe this classification may find utility in standardizing nomenclature for outcome tracking, treatment trials and physician communication.

Shape priors for segmentation of the cervix region within uterine cervix images

NASA Astrophysics Data System (ADS)

Lotenberg, Shelly; Gordon, Shiri; Greenspan, Hayit

2008-03-01

The work focuses on a unique medical repository of digital Uterine Cervix images ("Cervigrams") collected by the National Cancer Institute (NCI), National Institute of Health, in longitudinal multi-year studies. NCI together with the National Library of Medicine is developing a unique web-based database of the digitized cervix images to study the evolution of lesions related to cervical cancer. Tools are needed for the automated analysis of the cervigram content to support the cancer research. In recent works, a multi-stage automated system for segmenting and labeling regions of medical and anatomical interest within the cervigrams was developed. The current paper concentrates on incorporating prior-shape information in the cervix region segmentation task. In accordance with the fact that human experts mark the cervix region as circular or elliptical, two shape models (and corresponding methods) are suggested. The shape models are embedded within an active contour framework that relies on image features. Experiments indicate that incorporation of the prior shape information augments previous results.

Evaluation of the mineralization degree of the vestibular surface of the upper central incisors with a 655-nm diode laser in mouth breathers: preliminary results

NASA Astrophysics Data System (ADS)

Pinheiro Ladalardo, Thereza C. C. G.; Cappellette, Mario, Jr.; Zanin, Fatima A. A.; Brugnera, Aldo, Jr.; Anthero de Azevedo, Ramiro; Pignatari, Shirley; Weckx, Luc L. M.

2003-06-01

Mouth breathing unbalances the physiological mechanisms of the dental surface hydration by compromising lip closure, and, very often, causing the vestibular positioning of upper incisors. That variance leads to the interruption of the dental demineralization and remineralization feedback, prevailing a demineralized condition of the dental surface which increases caries risk. The laser fluorescence examination allows an early demineralization diagnosis, thus it makes possible through preventive measures to minimize the risk factor - dental mineral structure loss - in the bacterial infection of the demineralized area, and hence, preventing invasive therapeutical procedures. A DIAGNOdent apparatus was used to evaluate the mineralization degree of the upper central incisors in 40 patients - twenty of them with a mouth breathing diagnosis; the remaining twenty were nasal breathers (control group). Age ranging from 6 to 12 years, both male and female. To measure the vestibular surface of the incisors, it was divided into 3 segments: cervical, medial and incisal. The average of the results pertaining to the mouth breathing patients was as follows: tooth 11 cervical third - 5.45, medial third - 7.15, incisal third - 7.95, and tooth 21 - cervical third - 5.95, medial third - 7.25, incisal third - 8.15. The control patients, nasal breathers, presented the following results: tooth 11 cervical third - 1.75, medial third - 2.30, incisal third - 1.85, and tooth 21 - cervical third - 1.80, medial third - 2.20, incisal third - 2.15. The mouth breathing patients showed demineralization in the teeth examined at the initial stage, subclinical, comparing with the control patients, nasal breathers, who did not present any mineral deficit in these teeth.

Lynch syndrome and cervical cancer.

PubMed

Antill, Yoland C; Dowty, James G; Win, Aung Ko; Thompson, Tina; Walsh, Michael D; Cummings, Margaret C; Gallinger, Steven; Lindor, Noralane M; Le Marchand, Loïc; Hopper, John L; Newcomb, Polly A; Haile, Robert W; Church, James; Tucker, Katherine M; Buchanan, Daniel D; Young, Joanne P; Winship, Ingrid M; Jenkins, Mark A

2015-12-01

Carriers of germline mutations in DNA mismatch repair (MMR) genes are at increased risk of several cancers including colorectal and gynecologic cancers (Lynch syndrome). There is no substantial evidence that these mutations are associated with an increased risk of cervical cancer. A total of 369 families with at least one carrier of a mutation in a MMR gene (133 MLH1, 174 MSH2, 35 MSH6 and 27 PMS2) were ascertained via population cancer registries or via family cancer clinics in Australia, New Zealand, Canada, and USA. Personal and family histories of cancer were obtained from participant interviews. Modified segregation analysis was used to estimate the hazard ratio (incidence rates for carriers relative to those for the general population), and age-specific cumulative risks of cervical cancer for carriers. A total of 65 cases of cervical cancer were reported (including 10 verified by pathology reports). The estimated incidence was 5.6 fold (95% CI: 2.3-13.8; p = 0.001) higher for carriers than for the general population with a corresponding cumulative risk to 80 years of 4.5% (95% CI: 1.9-10.7%) compared with 0.8% for the general population. The mean age at diagnosis was 43.1 years (95% CI: 40.0-46.2), 3.9 years younger than the reported USA population mean of 47.0 years (p = 0.02). Women with MMR gene mutations were found to have an increased risk of cervical cancer. Due to limited pathology verification we cannot be certain that a proportion of these cases were not lower uterine segment endometrial cancers involving the endocervix, a recognized cancer of Lynch syndrome. © 2015 UICC.

Cervical lordotic alignment following posterior spinal fusion for adolescent idiopathic scoliosis: reciprocal changes and risk factors for malalignment.

PubMed

Hayashi, Kazunori; Toyoda, Hiromitsu; Terai, Hidetomi; Suzuki, Akinobu; Hoshino, Masatoshi; Tamai, Koji; Ohyama, Shoichiro; Nakamura, Hiroaki

2017-04-01

OBJECTIVE Numerous reports have been published on the effectiveness and safety of correction of the coronal Cobb angle and thoracolumbar sagittal alignment in patients with adolescent idiopathic scoliosis (AIS). Suboptimal sagittal alignment, such as decreased thoracic kyphosis (TK), after corrective surgery, is a possible cause of lumbar or cervical spinal degeneration and junctional malalignment; however, few reports are available on reciprocal changes outside of the fused segments, such as the cervical lordotic angle (CLA). This study aimed to investigate the relationship between the perioperative CLA and other radiographic factors or clinical results in AIS, and to identify independent risk factors of postoperative cervical hyperkyphosis. METHODS A total of 51 AIS patients who underwent posterior spinal fusion with the placement of pedicle screw (PS) constructs at thoracic levels were included in the study. Clinical and radiographic follow-up of patients was conducted for a minimum of 2 years, and the postoperative course was evaluated. The authors measured and identified the changes in the CLA and other radiographic parameters using whole-spine radiography, with the patient in the standing position, performed immediately before surgery, 2 weeks after surgery, and 2 years after surgery. The postoperative cervical hyperkyphosis group included patients whose CLA at 2-year follow-up was smaller than -10°. The reciprocal changes of the CLA and other parameters were also investigated. Univariate and multivariate analyses were conducted to determine the associated risk factors for postoperative cervical hyperkyphosis. RESULTS This study comprised 48 females and 3 males (mean age 16.0 years). The mean follow-up period was 47 months (range 24-90 months). The main coronal thoracic curve was corrected from 54.6° to 16.4°, and the mean correction rate was 69.8% at 2 years. The CLA significantly increased from the mean preoperative measurement (-5.4° ± 14°) to the 2-year follow-up measurement (-1.7° ± 11°) (p = 0.019). Twelve of the 51 patients had postoperative cervical hyperkyphosis. This group exhibited significantly smaller preoperative CLA and TK measurements (p = 0.001 and 0.004, respectively) than the others. After adjusting for confounding factors, preoperative CLA less than -5° and preoperative TK less than 10° were significantly associated with postoperative cervical hyperkyphosis (p < 0.05; OR 12.5 and 8.59, respectively). However, no differences were found in the clinical results regardless of cervical hyperkyphosis. CONCLUSIONS The CLA increased significantly from preoperatively to 2 years after surgery. Preoperative small CLA and TK measurements were independent risk factors of postoperative cervical hyperkyphosis. However, there was no difference in the clinical outcomes regardless of cervical hyperkyphosis.

SU-C-207B-03: A Geometrical Constrained Chan-Vese Based Tumor Segmentation Scheme for PET

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, L; Zhou, Z; Wang, J

Purpose: Accurate segmentation of tumor in PET is challenging when part of tumor is connected with normal organs/tissues with no difference in intensity. Conventional segmentation methods, such as thresholding or region growing, cannot generate satisfactory results in this case. We proposed a geometrical constrained Chan-Vese based scheme to segment tumor in PET for this special case by considering the similarity between two adjacent slices. Methods: The proposed scheme performs segmentation in a slice-by-slice fashion where an accurate segmentation of one slice is used as the guidance for segmentation of rest slices. For a slice that the tumor is not directlymore » connected to organs/tissues with similar intensity values, a conventional clustering-based segmentation method under user’s guidance is used to obtain an exact tumor contour. This is set as the initial contour and the Chan-Vese algorithm is applied for segmenting the tumor in the next adjacent slice by adding constraints of tumor size, position and shape information. This procedure is repeated until the last slice of PET containing tumor. The proposed geometrical constrained Chan-Vese based algorithm was implemented in Matlab and its performance was tested on several cervical cancer patients where cervix and bladder are connected with similar activity values. The positive predictive values (PPV) are calculated to characterize the segmentation accuracy of the proposed scheme. Results: Tumors were accurately segmented by the proposed method even when they are connected with bladder in the image with no difference in intensity. The average PPVs were 0.9571±0.0355 and 0.9894±0.0271 for 17 slices and 11 slices of PET from two patients, respectively. Conclusion: We have developed a new scheme to segment tumor in PET images for the special case that the tumor is quite similar to or connected to normal organs/tissues in the image. The proposed scheme can provide a reliable way for segmenting tumors.« less

Reproductive System of Brown-throated Sloth (Bradypus variegatus, Schinz 1825, Pilosa, Xenarthra): Anatomy and Histology.

PubMed

Favoretto, S M; daSilva, E G; Menezes, J; Guerra, R R; Campos, D B

2016-08-01

In recent years, habitat degradation led to the decline of some populations of brown-throated sloth. The aim of this study was to describe morphological features of the female reproductive system of the species. The oval ovaries were partially surrounded by ovarian bursa. An external cortex and an inner medulla were present. Corpora lutea and corpora albicans together with follicles at various stages of development each with a single oocyte were found in the cortex. Uterine tubes were tortuous, tubular, travelled around the perimeter of the ovary and possessed a folded mucosa with ciliated pseudostratified epithelium. Uterus was simplex, with no horns and divided into three parts: a pear-shaped cranial segment and a long caudal uterine segment (both forming the body of the uterus) and two cervices. Uterus presented three layers: mucosa, lined by pseudostratified epithelium, muscular and serosa. The cervices connected the uterus to the urogenital sinus, a distensible cavity with longitudinal mucosal folds lined by transitional epithelium that extended from the external urethral orifice and the external uterine ostia to the vulva, which was lined by a keratinized stratified squamous epithelium. Brown-throated sloth presented a bipartite clitoris with paired crura, bodies and glandes. The presence of a double cervix and a bipartite clitoris was unique features of the species. © 2015 Blackwell Verlag GmbH.

α-Synuclein pathology in the cranial and spinal nerves in Lewy body disease.

PubMed

Nakamura, Keiko; Mori, Fumiaki; Tanji, Kunikazu; Miki, Yasuo; Toyoshima, Yasuko; Kakita, Akiyoshi; Takahashi, Hitoshi; Yamada, Masahito; Wakabayashi, Koichi

2016-06-01

Accumulation of phosphorylated α-synuclein in neurons and glial cells is a histological hallmark of Lewy body disease (LBD) and multiple system atrophy (MSA). Recently, filamentous aggregations of phosphorylated α-synuclein have been reported in the cytoplasm of Schwann cells, but not in axons, in the peripheral nervous system in MSA, mainly in the cranial and spinal nerve roots. Here we conducted an immunohistochemical investigation of the cranial and spinal nerves and dorsal root ganglia of patients with LBD. Lewy axons were found in the oculomotor, trigeminal and glossopharyngeal-vagus nerves, but not in the hypoglossal nerve. The glossopharyngeal-vagus nerves were most frequently affected, with involvement in all of 20 subjects. In the spinal nerve roots, Lewy axons were found in all of the cases examined. Lewy axons in the anterior nerves were more frequent and numerous in the thoracic and sacral segments than in the cervical and lumbar segments. On the other hand, axonal lesions in the posterior spinal nerve roots appeared to increase along a cervical-to-sacral gradient. Although Schwann cell cytoplasmic inclusions were found in the spinal nerves, they were only minimal. In the dorsal root ganglia, axonal lesions were seldom evident. These findings indicate that α-synuclein pathology in the peripheral nerves is axonal-predominant in LBD, whereas it is restricted to glial cells in MSA. © 2015 Japanese Society of Neuropathology.

Provocative mechanical tests of the peripheral nervous system affect the joint torque-angle during passive knee motion.

PubMed

Andrade, R J; Freitas, S R; Vaz, J R; Bruno, P M; Pezarat-Correia, P

2015-06-01

This study aimed to determine the influence of the head, upper trunk, and foot position on the passive knee extension (PKE) torque-angle response. PKE tests were performed in 10 healthy subjects using an isokinetic dynamometer at 2°/s. Subjects lay in the supine position with their hips flexed to 90°. The knee angle, passive torque, surface electromyography (EMG) of the semitendinosus and quadriceps vastus medialis, and stretch discomfort were recorded in six body positions during PKE. The different maximal active positions of the cervical spine (neutral; flexion; extension), thoracic spine (neutral; flexion), and ankle (neutral; dorsiflexion) were passively combined for the tests. Visual analog scale scores and EMG were unaffected by body segment positioning. An effect of the ankle joint was verified on the peak torque and knee maximum angle when the ankle was in the dorsiflexion position (P < 0.05). Upper trunk positioning had an effect on the knee submaximal torque (P < 0.05), observed as an increase in the knee passive submaximal torque when the cervical and thoracic spines were flexed (P < 0.05). In conclusion, other apparently mechanical unrelated body segments influence torque-angle response since different positions of head, upper trunk, and foot induce dissimilar knee mechanical responses during passive extension. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Effects of sympathetic nerve stimulation on long posterior ciliary artery blood flow in cats.

PubMed

Koss, Michael C

2002-04-01

A new technique using ultrasonic flowmetry was developed in order to directly measure blood flow in the long posterior ciliary artery (LPCA) of anesthetized cats. Basal LPCA blood flow averaged about 0.6 ml/min and was stable over the experimental period. Electrical stimulation of the cervical preganglionic cervical sympathetic nerve produced frequency-dependent anterior segment ocular vasoconstrictor responses. Ipsilateral nictitating membrane contractions were simultaneously measured as a well-established index of neural sympathetic activation. LPCA frequency-response relationships were shifted to the right in comparison with those for the nictitating membrane. When elicited at two min intervals, submaximal evoked responses of both systems were stable for more than 90 min. Ocular vasoconstrictor and nictitating membrane responses were blocked in a dose-dependent fashion by intravenous treatment with the non-selective a-adrenoceptor antagonist, phentolamine (0.3-3.0 mg/kg), as well as with the selective alpha1-adrenoceptor antagonist, prazosin (3-30 microg/kg). In contrast, neither evoked response was further antagonized by subsequent administration of the alpha2-adrenoceptor antagonist, yohimbine (500 microg/kg). These results demonstrate the usefulness of ultrasonic flowmetry to study mechanisms controlling ocular anterior segment circulation and suggest that, as previously established for the nictitating membrane and anterior choroid, adrenergic neurogenic vasoconstriction in tissues perfused by the LPCA is mediated predominantly by alpha1-adrenoceptors.

The effect of surgical titanium rods on proton therapy delivered for cervical bone tumors: experimental validation using an anthropomorphic phantom

NASA Astrophysics Data System (ADS)

Dietlicher, Isabelle; Casiraghi, Margherita; Ares, Carmen; Bolsi, Alessandra; Weber, Damien C.; Lomax, Antony J.; Albertini, Francesca

2014-12-01

To investigate the effect of metal implants in proton radiotherapy, dose distributions of different, clinically relevant treatment plans have been measured in an anthropomorphic phantom and compared to treatment planning predictions. The anthropomorphic phantom, which is sliced into four segments in the cranio-caudal direction, is composed of tissue equivalent materials and contains a titanium implant in a vertebral body in the cervical region. GafChromic® films were laid between the different segments to measure the 2D delivered dose. Three different four-field plans have then been applied: a Single-Field-Uniform-Dose (SFUD) plan, both with and without artifact correction implemented, and an Intensity-Modulated-Proton-Therapy (IMPT) plan with the artifacts corrected. For corrections, the artifacts were manually outlined and the Hounsfield Units manually set to an average value for soft tissue. Results show a surprisingly good agreement between prescribed and delivered dose distributions when artifacts have been corrected, with > 97% and 98% of points fulfilling the gamma criterion of 3%/3 mm for both SFUD and the IMPT plans, respectively. In contrast, without artifact corrections, up to 18% of measured points fail the gamma criterion of 3%/3 mm for the SFUD plan. These measurements indicate that correcting manually for the reconstruction artifacts resulting from metal implants substantially improves the accuracy of the calculated dose distribution.

A small group Whiplash-Associated-Disorders (WAD) patients with central neck pain and movement induced stabbing pain, the painful segment determined by mechanical provocation: Fusion surgery was superior to multimodal rehabilitation in a randomized trial.

PubMed

Nyström, Bo; Svensson, Elisabeth; Larsson, Svante; Schillberg, Birgitta; Mörk, Ann; Taube, Adam

2016-07-01

The majority of patients suffering from a whiplash injury will recover, but some will have symptoms (Whiplash Associated Disorders, WAD) for years despite conservative treatment. Some of these patients perceive neck pain that might come from a motion segment, possibly the disc. In comprehensive reviews no evidence has been found that fusion operations have a positive treatment effect on neck pain in WAD patients. Our aim was to evaluate the possibility of (a) selecting a subgroup of chronic WAD patients based on specified symptoms possibly indicating segmental pain, and (b) treating said segmental pain through fusion operation based on non-radiological segment localization. The hypothesis was that fusion operation in this selected subgroup of chronic WAD patients could alleviate perceived neck pain. Eligible patients for the study had a traffic accident as the origin for their neck pain, and no previous neck symptoms. Neck pain should be the predominant symptom and the pain origin reported to be in the midline, being dull, aching in character and at sudden movements combined by a stabbing pain in the same area. Forty-nine patients with these specified symptoms were identified among a large number of chronic WAD patients. Those selected had pronounced symptoms for a median of around 50 months and had previously been investigated and fully treated within the ordinary healthcare system without success. No neurological abnormalities were to be found at clinical examination and no specific changes to be seen on X-ray and MRI. The patients were randomized to either cervical fusion operation or multimodal rehabilitation. By using a mechanical provocation test the level/s to be fused were identified. In all but one patient the surgery was performed anteriorly using microsurgical technique and a right-sided Smith-Pedersen approach and plate fixation. The multimodal rehabilitation at the Clinic of Medical Rehabilitation, Karolinska Hospital, Stockholm, included outpatient treatment for four days a week for six weeks and included treatment by physician, physiotherapists, occupational therapist, psychologists, social-service worker and nurses. Perceived change in neck pain was assessed using the Balanced Inventory for Spinal Disorders questionnaire at the 2-year-follow-up. Mean age of the patients was 38 and 40 years (surgery and rehabilitation groups, respectively), the most common type of accident being rear-end collision. At clinical examination muscle tenderness was not an outstanding sign. In most patients the mid-cervical region appeared to be the painful area but one patient localized the pain to C1. At follow-up 67% of the patients in the surgery group and 23% in the rehabilitation group assessed improvements in the ITT analysis. Corresponding proportions in the per protocol analysis were 83% and 12%, respectively. The results support the supposition that among patients with central neck pain for long periods of time following a whiplash injury there are some in whom the neck pain emanates from a motion segment, probably the disc, a situation suitable for fusion surgery. Thorough individual symptom evaluation in patients with chronic WAD may identify patients who will benefit from cervical fusion surgery. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

A case report of spondylectomy with circumference reconstruction for aggressive vertebral hemangioma covering the whole cervical spine (C4) with progressive spinal disorder.

PubMed

Nakahara, Masayuki; Nishida, Kenki; Kumamoto, Shinji; Hijikata, Yasukazu; Harada, Kei

2017-05-01

To describe the surgical experience of spondylectomy and spinal reconstruction for aggressive vertebral hemangioma (VH) induced at the C4 vertebra. No reports have described surgical strategy in cases covering an entire cervical vertebra presenting with progressive myelopathy. A 28-year-old man presented with rapidly progressing skilled motor dysfunction and gait disorder. The Japanese Orthopedic Association (JOA) score was 6. Radiography showed a honeycomb appearance for the entire circumference of the C4 vertebra. Spinal computed tomography and magnetic resonance imaging showed vertebral tumor with extraosseous extension causing spinal cord compression. Results of diagnostic imaging were strongly suggestive of VH. Transarterial embolization of the spinal body branch was performed first to decrease intraoperative bleeding, followed by cervical posterior fixation to stabilize the unstable segment and excision biopsy to obtain a definitive diagnosis. After definitive diagnosis of cavernous hemangioma, two-stage surgery (anterior and posterior) was performed to complete total spondylectomy and 360° spinal reconstruction. Despite multiple operations, JOA scores were 8.5 after posterior fixation, 10.5 after anterior surgery, 11 after final surgery and 16 on postoperative day 90. The patient acquired excellent clinical results without complications and returned to society. The present three-stage surgery comprising fixation, biopsy, and final spondylectomy with circumferential fusion from anterior and posterior approaches may offer a useful choice for aggressive VH covering the entire cervical spine with rapidly progressive myelopathy.

Lumbar intervertebral disc allograft transplantation: long-term mobility and impact on the adjacent segments.

PubMed

Huang, Yong-Can; Xiao, Jun; Lu, William W; Leung, Victor Y L; Hu, Yong; Luk, Keith D K

2017-03-01

Fresh-frozen intervertebral disc (IVD) allograft transplantation has been successfully performed in the human cervical spine. Whether this non-fusion technology could truly decrease adjacent segment disease is still unknown. This study evaluated the long-term mobility of the IVD-transplanted segment and the impact on the adjacent spinal segments in a goat model. Twelve goats were used. IVD allograft transplantation was performed at lumbar L4/L5 in 5 goats; the other 7 goats were used as the untreated control (5) and for the supply of allografts (2). Post-operation lateral radiographs of the lumbar spine in the neutral, full-flexion and full-extension positions were taken at 1, 3, 6, 9 and 12 months. Disc height (DH) of the allograft and the adjacent levels was calculated and range of motion (ROM) was measured using the Cobb's method. The anatomy of the adjacent discs was observed histologically. DH of the transplanted segment was decreased significantly after 3 months but no further reduction was recorded until the final follow-up. No obvious alteration was seen in the ROM of the transplanted segment at different time points with the ROM at 12 months being comparable to that of the untreated control. The DH and ROM in the adjacent segments were well maintained during the whole observation period. At post-operative 12 months, the ROM of the adjacent levels was similar to that of the untreated control and the anatomical morphology was well preserved. Lumbar IVD allograft transplantation in goats could restore the segmental mobility and did not negatively affect the adjacent segments after 12 months.

Efficient segmentation of 3D fluoroscopic datasets from mobile C-arm

NASA Astrophysics Data System (ADS)

Styner, Martin A.; Talib, Haydar; Singh, Digvijay; Nolte, Lutz-Peter

2004-05-01

The emerging mobile fluoroscopic 3D technology linked with a navigation system combines the advantages of CT-based and C-arm-based navigation. The intra-operative, automatic segmentation of 3D fluoroscopy datasets enables the combined visualization of surgical instruments and anatomical structures for enhanced planning, surgical eye-navigation and landmark digitization. We performed a thorough evaluation of several segmentation algorithms using a large set of data from different anatomical regions and man-made phantom objects. The analyzed segmentation methods include automatic thresholding, morphological operations, an adapted region growing method and an implicit 3D geodesic snake method. In regard to computational efficiency, all methods performed within acceptable limits on a standard Desktop PC (30sec-5min). In general, the best results were obtained with datasets from long bones, followed by extremities. The segmentations of spine, pelvis and shoulder datasets were generally of poorer quality. As expected, the threshold-based methods produced the worst results. The combined thresholding and morphological operations methods were considered appropriate for a smaller set of clean images. The region growing method performed generally much better in regard to computational efficiency and segmentation correctness, especially for datasets of joints, and lumbar and cervical spine regions. The less efficient implicit snake method was able to additionally remove wrongly segmented skin tissue regions. This study presents a step towards efficient intra-operative segmentation of 3D fluoroscopy datasets, but there is room for improvement. Next, we plan to study model-based approaches for datasets from the knee and hip joint region, which would be thenceforth applied to all anatomical regions in our continuing development of an ideal segmentation procedure for 3D fluoroscopic images.

SU-E-T-580: Comparison of Cervical Carcinoma IMRT Plans From Four Commercial Treatment Planning Systems (TPS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, Y; Li, R; Chi, Z

2014-06-01

Purpose: Different treatment planning systems (TPS) use different treatment optimization and leaf sequencing algorithms. This work compares cervical carcinoma IMRT plans optimized with four commercial TPSs to investigate the plan quality in terms of target conformity and delivery efficiency. Methods: Five cervical carcinoma cases were planned with the Corvus, Monaco, Pinnacle and Xio TPSs by experienced planners using appropriate optimization parameters and dose constraints to meet the clinical acceptance criteria. Plans were normalized for at least 95% of PTV to receive the prescription dose (Dp). Dose-volume histograms and isodose distributions were compared. Other quantities such as Dmin(the minimum dose receivedmore » by 99% of GTV/PTV), Dmax(the maximum dose received by 1% of GTV/PTV), D100, D95, D90, V110%, V105%, V100% (the volume of GTV/PTV receiving 110%, 105%, 100% of Dp), conformity index(CI), homogeneity index (HI), the volume of receiving 40Gy and 50 Gy to rectum (V40,V50) ; the volume of receiving 30Gy and 50 Gy to bladder (V30,V50) were evaluated. Total segments and MUs were also compared. Results: While all plans meet target dose specifications and normal tissue constraints, the maximum GTVCI of Pinnacle plans was up to 0.74 and the minimum of Corvus plans was only 0.21, these four TPSs PTVCI had significant difference. The GTVHI and PTVHI of Pinnacle plans are all very low and show a very good dose distribution. Corvus plans received the higer dose of normal tissue. The Monaco plans require significantly less segments and MUs to deliver than the other plans. Conclusion: To deliver on a Varian linear-accelerator, the Pinnacle plans show a very good dose distribution. Corvus plans received the higer dose of normal tissue. The Monaco plans have faster beam delivery.« less

Morphological and neurochemical differences in peptidergic nerve fibers of the mouse vagina.

PubMed

Barry, Christine M; Ji, Esther; Sharma, Harman; Beukes, Lara; Vilimas, Patricia I; DeGraaf, Yvette C; Matusica, Dusan; Haberberger, Rainer V

2017-07-01

The vagina is innervated by a complex arrangement of sensory, sympathetic, and parasympathetic nerve fibers that contain classical transmitters plus an array of neuropeptides and enzymes known to regulate diverse processes including blood flow and nociception. The neurochemical characteristics and distributions of peptide-containing nerves in the mouse vagina are unknown. This study used multiple labeling immunohistochemistry, confocal maging and analysis to investigate the presence and colocalization of the peptides vasoactive intestinal polypeptide (VIP), calcitonin-gene related peptide (CGRP), substance P (SP), neuropeptide tyrosine (NPY), and the nitric oxide synthesizing enzyme neuronal nitric oxide synthase (nNOS) in nerve fibers of the murine vaginal wall. We compared cervical and vulvar areas of the vagina in young nullipara and older multipara C57Bl/6 mice, and identified differences including that small ganglia were restricted to cervical segments, epithelial fibers were mainly present in vulvar segments and most nerve fibers were found in the lamina propria of the cervical region of the vagina, where a higher number of fibers containing immunoreactivity for VIP, CGRP, SP, or nNOS were found. Two populations of VIP-containing fibers were identified: fibers containing CGRP and fibers containing VIP but not CGRP. Differences between young and older mice were present in multiple layers of the vaginal wall, with older mice showing overall loss of innervation of epithelium of the proximal vagina and reduced proportions of VIP, CGRP, and SP containing nerve fibers in the distal epithelium. The distal vagina also showed increased vascularization and perivascular fibers containing NPY. Immunolabeling of ganglia associated with the vagina indicated the likely origin of some peptidergic fibers. Our results reveal regional differences and age- or parity-related changes in innervation of the mouse vagina, effecting the distribution of neuropeptides with diverse roles in function of the female genital tract. © 2017 Wiley Periodicals, Inc.

Sagittal alignment after single cervical disc arthroplasty.

PubMed

Guérin, Patrick; Obeid, Ibrahim; Gille, Olivier; Bourghli, Anouar; Luc, Stéphane; Pointillart, Vincent; Vital, Jean-Marc

2012-02-01

Prospective study. To analyze the sagittal balance after single-level cervical disc replacement (CDR) and range of motion (ROM). To define clinical and radiologic parameters those have a significant correlation with segmental and overall cervical curvature after CDR. Clinical outcomes and ROM after CDR with Mobi-C (LDR, Troyes, France) prosthesis have been documented in few studies. No earlier report of this prosthesis has studied correlations between static and dynamic parameters or those between static parameters and clinical outcomes. Forty patients were evaluated. Clinical outcome was assessed using the Short Form-36 questionnaire, Neck Disability Index, and a Visual Analog Scale. Spineview software (Surgiview, Paris, France) was used to investigate sagittal balance parameters and ROM. The mean follow-up was 24.3 months (range: 12 to 36 mo). Clinical outcomes were satisfactory. There was a significant improvement of Short Form-36, Neck Disability Index, and Visual Analog Scale scores. Mean ROM was 8.3 degrees preoperatively and 11.0 degrees postoperatively (P=0.013). Mean preoperative C2C7 curvature was 12.8 and 16.0 degrees at last follow-up (P=0.001). Mean preoperative functional spinal unit (FSU) angle was 2.3 and 5.3 degrees postoperatively (P<0.0001). Mean postoperative shell angle was 5.5 degrees. There was a significant correlation between postoperative C2C7 alignment and preoperative C2C7 alignment, change of C2C7 alignment, preoperative and postoperative FSU angle, and prosthesis shell angle. There was also a significant correlation between postoperative FSU angle and preoperative C2C7 alignment, preoperative FSU angle, change of FSU angle, and prosthesis shell angle. Regression analysis showed that prosthesis shell angle and preoperative FSU angle contributed significantly to postoperative FSU angle. Moreover, preoperative C2C7 alignment, preoperative FSU angle, postoperative FSU angle, and prosthesis shell angle contributed significantly to postoperative C2C7 alignment. No significant correlation was observed between ROM and sagittal parameters. Few correlations were found between sagittal alignment and clinical results. CDR with this prosthesis provided favorable clinical outcomes and maintains ROM of the FSU, overall and segmental cervical alignment. Long-term follow-up will be needed to assess the effectiveness and advantages of this procedure.

[Efficacy of 3D print guide technique in one stage posterior approach for the treatment of cervical and thoracic tuberculosis with kyphosis].

PubMed

Shaxika, Nazierhan; Sun, Z G; Yuan, H; Wang, H

2017-11-21

Objective: To investigate the application of 3D printing technology in the treatment of patients with cervical kyphosis and paraplegia in different segments of the cervical spine after one-stage debridement, bone graft fusion and pedicle screw fixation. Methods: From January 2008 to January 2017, a total of 31 patients with thoracolumbar tuberculosis were treated in the Department of Orthopaedics, the Xinjiang Uygur Autonomous Region people's Hospital.Lesions of the thoracic spine (T1-T4) in 8 cases, (C5-C7) in 10 cases, cervical and thoracic segment in 13 cases, involving a total of 2 cases of vertebral body in 7 cases, 3 cases of vertebral body in 14 cases, 4 cases of vertebral body. 3D printing group (group A) 12 cases, non 3D printing group (group B) of 19 cases.All cases were treated with a posterior approach to the treatment of the cervical spinal cord around the spinal cord.After taking regular anti tuberculosis drugs in 6-12 months, follow-up observation of correction of kyphosis and paraplegia recovery, blood sedimentation rate (ESR), C-reactive protein (CRP) changes. Results: All cases were followed up for at least 6 months. Twelve patients were treated with 3D printing technique before operation, and the operation was performed according to the preoperative plan.The diameter and length of pedicle screws, the direction of insertion, and the distance between the insertion point and the posterior midline of the pedicle screw were similar to those in the 3D.Three days after the operation, the effect of fracture reduction was satisfactory, and the position of pedicle screws was good.After 6 months of follow-up, the X-ray showed that the pedicle screws were in good position, and there was no loosening and fracture.All the patients were healed, and there was no segmental instability.3D printing group during surgery bleeding, operation time, postoperative drainage volume, compared with the non 3D print group of surgical results, 3D printing group significantly reduce the surgical trauma[(131±18) min vs (162±23), P <0.01; (528±34) ml vs (615±41) ml, P <0.01; (257±46) vs (327±56), P <0.01; (not grouping, before after operation), (64±42) mm/1 h vs (6±7) mm/1 h, P <0.01; CRP (not packet): (72±41) μg/L, (13±6) mm/1 h, P <0.01]. There was significant difference between two groups.The JOA scores of patients in the 3D group were better than those in the non 3D group after the operation in 1, 2 week and in 1, 3, and month.There was no significant difference between the two groups after the operation.Two groups of patients before and after correction of Cobb angle were satisfied, and no significant difference between the two groups.Cobb lost an average of 1 degrees angle correction.The spinal tuberculosis in this group were cured without serious complications. Conclusions: According to the cervical and thoracic tuberculous kyphosis and paraplegia severity, choose a posterior surgery can achieve effective cure, feasible thorough debridement with fixed spinal stability before and after the party obtained bone fusion and deformity correction in 3D technology to increase the accuracy and safety of operation, and can be provide more detailed preoperative, intuitive, three-dimensional, realistic personalized operation scheme.It can reduce the operation trauma, and achieve rapid recovery after operation.

Automatic and hierarchical segmentation of the human skeleton in CT images.

PubMed

Fu, Yabo; Liu, Shi; Li, Harold; Yang, Deshan

2017-04-07

Accurate segmentation of each bone of the human skeleton is useful in many medical disciplines. The results of bone segmentation could facilitate bone disease diagnosis and post-treatment assessment, and support planning and image guidance for many treatment modalities including surgery and radiation therapy. As a medium level medical image processing task, accurate bone segmentation can facilitate automatic internal organ segmentation by providing stable structural reference for inter- or intra-patient registration and internal organ localization. Even though bones in CT images can be visually observed with minimal difficulty due to the high image contrast between the bony structures and surrounding soft tissues, automatic and precise segmentation of individual bones is still challenging due to the many limitations of the CT images. The common limitations include low signal-to-noise ratio, insufficient spatial resolution, and indistinguishable image intensity between spongy bones and soft tissues. In this study, a novel and automatic method is proposed to segment all the major individual bones of the human skeleton above the upper legs in CT images based on an articulated skeleton atlas. The reported method is capable of automatically segmenting 62 major bones, including 24 vertebrae and 24 ribs, by traversing a hierarchical anatomical tree and by using both rigid and deformable image registration. The degrees of freedom of femora and humeri are modeled to support patients in different body and limb postures. The segmentation results are evaluated using the Dice coefficient and point-to-surface error (PSE) against manual segmentation results as the ground-truth. The results suggest that the reported method can automatically segment and label the human skeleton into detailed individual bones with high accuracy. The overall average Dice coefficient is 0.90. The average PSEs are 0.41 mm for the mandible, 0.62 mm for cervical vertebrae, 0.92 mm for thoracic vertebrae, and 1.45 mm for pelvis bones.

Automatic and hierarchical segmentation of the human skeleton in CT images

NASA Astrophysics Data System (ADS)

Fu, Yabo; Liu, Shi; Li, H. Harold; Yang, Deshan

2017-04-01

Accurate segmentation of each bone of the human skeleton is useful in many medical disciplines. The results of bone segmentation could facilitate bone disease diagnosis and post-treatment assessment, and support planning and image guidance for many treatment modalities including surgery and radiation therapy. As a medium level medical image processing task, accurate bone segmentation can facilitate automatic internal organ segmentation by providing stable structural reference for inter- or intra-patient registration and internal organ localization. Even though bones in CT images can be visually observed with minimal difficulty due to the high image contrast between the bony structures and surrounding soft tissues, automatic and precise segmentation of individual bones is still challenging due to the many limitations of the CT images. The common limitations include low signal-to-noise ratio, insufficient spatial resolution, and indistinguishable image intensity between spongy bones and soft tissues. In this study, a novel and automatic method is proposed to segment all the major individual bones of the human skeleton above the upper legs in CT images based on an articulated skeleton atlas. The reported method is capable of automatically segmenting 62 major bones, including 24 vertebrae and 24 ribs, by traversing a hierarchical anatomical tree and by using both rigid and deformable image registration. The degrees of freedom of femora and humeri are modeled to support patients in different body and limb postures. The segmentation results are evaluated using the Dice coefficient and point-to-surface error (PSE) against manual segmentation results as the ground-truth. The results suggest that the reported method can automatically segment and label the human skeleton into detailed individual bones with high accuracy. The overall average Dice coefficient is 0.90. The average PSEs are 0.41 mm for the mandible, 0.62 mm for cervical vertebrae, 0.92 mm for thoracic vertebrae, and 1.45 mm for pelvis bones.

A probabilistic approach to segmentation and classification of neoplasia in uterine cervix images using color and geometric features

NASA Astrophysics Data System (ADS)

Srinivasan, Yeshwanth; Hernes, Dana; Tulpule, Bhakti; Yang, Shuyu; Guo, Jiangling; Mitra, Sunanda; Yagneswaran, Sriraja; Nutter, Brian; Jeronimo, Jose; Phillips, Benny; Long, Rodney; Ferris, Daron

2005-04-01

Automated segmentation and classification of diagnostic markers in medical imagery are challenging tasks. Numerous algorithms for segmentation and classification based on statistical approaches of varying complexity are found in the literature. However, the design of an efficient and automated algorithm for precise classification of desired diagnostic markers is extremely image-specific. The National Library of Medicine (NLM), in collaboration with the National Cancer Institute (NCI), is creating an archive of 60,000 digitized color images of the uterine cervix. NLM is developing tools for the analysis and dissemination of these images over the Web for the study of visual features correlated with precancerous neoplasia and cancer. To enable indexing of images of the cervix, it is essential to develop algorithms for the segmentation of regions of interest, such as acetowhitened regions, and automatic identification and classification of regions exhibiting mosaicism and punctation. Success of such algorithms depends, primarily, on the selection of relevant features representing the region of interest. We present color and geometric features based statistical classification and segmentation algorithms yielding excellent identification of the regions of interest. The distinct classification of the mosaic regions from the non-mosaic ones has been obtained by clustering multiple geometric and color features of the segmented sections using various morphological and statistical approaches. Such automated classification methodologies will facilitate content-based image retrieval from the digital archive of uterine cervix and have the potential of developing an image based screening tool for cervical cancer.

Hydrogeologic framework of the uppermost principal aquifer systems in the Williston and Powder River structural basins, United States and Canada

USGS Publications Warehouse

Thamke, Joanna N.; LeCain, Gary D.; Ryter, Derek W.; Sando, Roy; Long, Andrew J.

2014-01-01

Regionally, water in the lower Tertiary and Upper Cretaceous aquifer systems flows in a northerly or northeasterly direction from the Powder River structural basin to the Williston structural basin. Groundwater flow in the Williston structural basin generally is easterly or northeasterly. Flow in the uppermost hydrogeologic units generally is more local and controlled by topography where unglaciated in the Williston structural basin than is flow in the glaciated part and in underlying aquifers. Groundwater flow in the Powder River structural basin generally is northerly with local variations greatest in the uppermost aquifers. Groundwater is confined, and flow is regional in the underlying aquifers.

Meige Syndrome: What’s in a Name?

PubMed Central

LeDoux, Mark S.

2009-01-01

Frequently, blepharospasm is associated with involuntary movements of the platysma, lower face and masticatory muscles. Similarly, masticatory dystonia may occur in isolation or in combination with dystonia of other cranial and cervical muscles. The non-possessive and possessive forms of Meige and Brueghel syndromes have been variably and imprecisely ascribed to various anatomical variations of craniocervical dystonia. Herein, the origin of eponymic terms as applied to craniocervical dystonia is reviewed as support for proposed elimination of these eponyms from clinical usage. Although the term “segmental craniocervical dystonia” more accurately captures the combination of blepharospasm and dystonia of other head and neck muscles, delineation of craniocervical subphenotypes is essential for etiological/genetic and treatment studies. To conclude, the clinical features, epidemiology, pathophysiology and therapeutic management of segmental craniocervical dystonia are examined with a particular focus on “blepharospasm-plus” subphenotypes. PMID:19457699

Minimally Invasive Drainage of a Post-Laminectomy Subfascial Seroma with Cervical Spinal Cord Compression.

PubMed

Kitshoff, Adriaan Mynhardt; Van Goethem, Bart; Cornelis, Ine; Combes, Anais; Dvm, Ingeborgh Polis; Gielen, Ingrid; Vandekerckhove, Peter; de Rooster, Hilde

2016-01-01

A 14 mo old female neutered Doberman pinscher was evaluated for difficulty in rising, a wide based stance, pelvic limb gait abnormalities, and cervical pain of 2 mo duration. Neurologic examination revealed pelvic limb ataxia and cervical spinal hyperesthesia. Spinal reflexes and cranial nerve examination were normal. The pathology was localized to the C1-C5 or C6-T2 spinal cord segments. Computed tomography (CT) findings indicated bony proliferation of the caudal articular processes of C6 and the cranial articular processes of C7, resulting in bilateral dorsolateral spinal cord compression that was more pronounced on the left side. A limited dorsal laminectomy was performed at C6-C7. Due to progressive neurological deterioration, follow-up CT examination was performed 4 days postoperatively. At the level of the laminectomy defect, a subfacial seroma had developed, entering the spinal canal and causing significant spinal cord compression. Under ultrasonographic guidance a closed-suction wound catheter was placed. Drainage of the seroma successfully relieved its compressive effects on the spinal cord and the patient's neurological status improved. CT was a valuable tool in assessing spinal cord compression as a result of a postoperative subfascial seroma. Minimally invasive application of a wound catheter can be successfully used to manage this condition.

Spinal cord atrophy in anterior-posterior direction reflects impairment in multiple sclerosis.

PubMed

Lundell, H; Svolgaard, O; Dogonowski, A-M; Romme Christensen, J; Selleberg, F; Soelberg Sørensen, P; Blinkenberg, M; Siebner, H R; Garde, E

2017-10-01

To investigate how atrophy is distributed over the cross section of the upper cervical spinal cord and how this relates to functional impairment in multiple sclerosis (MS). We analysed the structural brain MRI scans of 54 patients with relapsing-remitting MS (n=22), primary progressive MS (n=9), secondary progressive MS (n=23) and 23 age- and sex-matched healthy controls. We measured the cross-sectional area (CSA), left-right width (LRW) and anterior-posterior width (APW) of the spinal cord at the segmental level C2. We tested for a nonparametric linear relationship between these atrophy measures and clinical impairments as reflected by the Expanded Disability Status Scale (EDSS) and Multiple Sclerosis Impairment Scale (MSIS). In patients with MS, CSA and APW but not LRW were reduced compared to healthy controls (P<.02) and showed significant correlations with EDSS, MSIS and specific MSIS subscores. In patients with MS, atrophy of the upper cervical cord is most evident in the antero-posterior direction. As APW of the cervical cord can be readily derived from standard structural MRI of the brain, APW constitutes a clinically useful neuroimaging marker of disease-related neurodegeneration in MS. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Degenerative myelopathy and vitamin A deficiency in a young black-maned lion (Panthera leo).

PubMed

Maratea, Kimberly A; Hooser, Stephen B; Ramos-Vara, José A

2006-11-01

Degenerative myelopathy and vitamin A deficiency were diagnosed in a 1-year-old, female, black-maned lion (Panthera leo). Diffuse white matter degeneration characterized by dilated myelin sheaths, Wallerian degeneration, and reactive astrocytosis was present at all levels of the spinal cord. With luxol fast blue-resyl echt violet stain, bilaterally symmetrical demyelination was observed in the fasciculus cuneatus of the cervical spinal cord and in peripheral white matter of cervical, thoracic, and lumbar segments. Additionally, the ventral gray columns and brain stem nuclei contained rare chromatolytic neurons with abnormal neurofilament accumulation. Leptomeninges of the cervical spinal cord were focally adhered to the dura and thickened by fibrosis and osseous metaplasia. Vitamin A deficiency was diagnosed based on hepatic vitamin A concentration of 1.71 microg/g dry weight. Adequate hepatic vitamin A concentration for yearling to adult domestic animals ranges between 150 and 1000 microg/g dry weight. Lesions were distinct from those previously described in young captive lions with vitamin A deficiency, which had thickened skull bones and cerebellar herniation. The pathogenesis of vitamin A-associated myelopathy in this lion may be similar to that described in adult cattle, which is believed to result from spinal cord compression secondary to elevated pressure of cerebrospinal fluid.

Planktonic foraminifers and radiolarians from the Coniacian-santonian deposits of the Mt. Ak-Kaya, Crimean Mountains, Ukraine

NASA Astrophysics Data System (ADS)

Korchagin, O. A.; Bragina, L. G.; Bragin, N. Yu.

2012-02-01

The first data on the distribution of planktonic foraminifers and radiolarians in the Mt. Ak-Kaya section, the central Crimean Mountains, are considered. According to the analyzed distribution of foraminifers, the Upper Cretaceous deposits of the section are subdivided into three biostratigraphic units: the Marginotruncana austinensis-Globotruncana desioi (presumably upper Coniacian), Sigalia carpatica (uppermost Coniacian-lower Santonian), and Contusotruncana fornicata-Marginotruncana marginata (upper Santonian) beds. Subdivisions substantiated by distribution of radiolarians are the Alievium praegallowayi-Crucella plana (upper Coniacian-lower Santonian), Alievium gallowayi-Crucella espartoensis (the upper Santonian excluding its uppermost part), and Dictyocephalus (Dictyocryphalus) (?) legumen-Spongosaturninus parvulus (the uppermost Santonian) beds. The Contusotruncana fornicata-Marginotruncana marginata Beds are concurrent to the middle part of the Marsupites laevigatus Zone coupled with the Marsupites testudinarius Zone (the uppermost Santonian). The Alievium gallowayi-Crucella espartoensis Beds are correlative with the upper part of the Alievium gallowayi Zone in the Californian radiolarian zonation. The cooccurring assemblages of planktonic foraminifers and radiolarians provide a possibility to correlate the Coniacian-Santonian deposits within the Crimea-Caucasus region.

Characteristics of Modic changes in cervical kyphosis and their association with axial neck pain.

PubMed

An, Yonghui; Li, Jia; Li, Yongqian; Shen, Yong

2017-01-01

The purpose of this study was to evaluate characteristics of Modic changes in cervical kyphosis (CK) and their association with axial neck pain. Study participants included 286 asymptomatic or symptomatic patients with CK (mean age = 54.2 ± 12.2 years) who were consecutively enrolled from March 2009 to October 2015. Clinical and radiographic evaluations were performed at a university outpatient department. CK was classified as global type, reverse sigmoid type, or sigmoid type. There were 138 participants with global type CK, 103 with reverse sigmoid type CK, and 45 with sigmoid type CK. Of the 286 participants, 102 had Modic changes (Modic-1 in 38 segments and Modic-2 in 75 segments). Spinal cord compression grade and disc degeneration occurred more frequently in the group with axial neck pain compared to the group without pain. Angular motion was decreased in those with axial neck pain (mean ± standard deviation [SD] 7.8°±4.6°) compared to those who were asymptomatic (mean ± SD 8.9°±5.1°; P <0.001). In multivariate logistic regression analysis, Modic changes were associated with axial neck pain (odds ratio =5.356; 95% confidence interval =1.314-12.800; P <0.001). Modic changes occur most commonly in association with CK global type and less commonly with reverse sigmoid type and sigmoid type. Modic changes are associated with axial neck pain in patients with CK.

Diffuse skull base/cervical fusion syndromes in two siblings with spondylocostal dysostosis syndrome: analysis via three dimensional computed tomography scanning.

PubMed

Al Kaissi, Ali; Ben Chehida, Farid; Ben Ghachem, Maher; Klaushofer, Klaus; Grill, Franz

2008-06-01

A study on a pair of male sibs to reach for the etiological understanding of unusual skull base/spine maldevelopment. Previously, radiographs alone were used to formulate this diagnosis. Here, three-dimensional computed tomography (3D CT) studies further clarified the typical diagnostic findings associated with spondylocostal dysostosis (SCD). Interestingly, patients with SCD are at increased risk for diffuse skull base/cervical fusion syndromes and can result in severe neurologic deficits associated with any degree of trauma. Classically SCD is defined as a skeletal dysplasia with clinical and radiologic manifestations, consisting of short neck and trunk, nonprogressive scoliosis and abnormalities of vertebral segmentation and of the ribs. Radiograms have been adopted as the only modality for the classification and prognostication of patients with SCD. Detailed clinical and radiographic examinations were undertaken with emphasis on the significance of the 3D CT scanning. We observed extensive fusion of the clivus with the cervical/entire spine, resulting in a remarkable solid, immobile, and fixed bony ankylosis of extremely serious outcome. Patients with spondylcostal dysostosis are predisposed to develop extensive skull-base-cervical spine fusion. The latter might lead to the development of a solid, immobile, and fixed bony ankylosis. In children/adults trivial injuries and/or high-energy trauma can lead to serious intracranial and spinal cord injury. Comprehensive orthopedic and neurosurgeons management must follow the recognition of these anomalies. To the best of our knowledge, no previous CT studies of the spine have been published in patients with SCD.

Anatomical and Molecular Properties of Long Descending Propriospinal Neurons in Mice

PubMed Central

Flynn, Jamie R.; Conn, Victoria L.; Boyle, Kieran A.; Hughes, David I.; Watanabe, Masahiko; Velasquez, Tomoko; Goulding, Martyn D.; Callister, Robert J.; Graham, Brett A.

2017-01-01

Long descending propriospinal neurons (LDPNs) are interneurons that form direct connections between cervical and lumbar spinal circuits. LDPNs are involved in interlimb coordination and are important mediators of functional recovery after spinal cord injury (SCI). Much of what we know about LDPNs comes from a range of species, however, the increased use of transgenic mouse lines to better define neuronal populations calls for a more complete characterisation of LDPNs in mice. In this study, we examined the cell body location, inhibitory neurotransmitter phenotype, developmental provenance, morphology and synaptic inputs of mouse LDPNs throughout the cervical and upper thoracic spinal cord. LDPNs were retrogradely labelled from the lumbar spinal cord to map cell body locations throughout the cervical and upper thoracic segments. Ipsilateral LDPNs were distributed throughout the dorsal, intermediate and ventral grey matter as well as the lateral spinal nucleus and lateral cervical nucleus. In contrast, contralateral LDPNs were more densely concentrated in the ventromedial grey matter. Retrograde labelling in GlyT2GFP and GAD67GFP mice showed the majority of inhibitory LDPNs project either ipsilaterally or adjacent to the midline. Additionally, we used several transgenic mouse lines to define the developmental provenance of LDPNs and found that V2b positive neurons form a subset of ipsilaterally projecting LDPNs. Finally, a population of Neurobiotin (NB) labelled LDPNs were assessed in detail to examine morphology and plot the spatial distribution of contacts from a variety of neurochemically distinct axon terminals. These results provide important baseline data in mice for future work on their role in locomotion and recovery from SCI. PMID:28220062

Activity-Based Therapies To Promote Forelimb Use after a Cervical Spinal Cord Injury

PubMed Central

Dai, Haining; MacArthur, Linda; McAtee, Marietta; Hockenbury, Nicole; Tidwell, J. Lille; McHugh, Brian; Mansfield, Kevin; Finn, Tom; Hamers, Frank P.T.

2009-01-01

Abstract Significant interest exists in strategies for improving forelimb function following spinal cord injury. We investigated the effect of enriched housing combined with skilled training on the recovery of skilled and automatic forelimb function after a cervical spinal cord injury in adult rats. All animals were pretrained in skilled reaching, gridwalk crossing, and overground locomotion. Some received a cervical over-hemisection lesion at C4-5, interrupting the right side of the spinal cord and dorsal columns bilaterally, and were housed in standard housing alone or enriched environments with daily training. A subset of animals received rolipram to promote neuronal plasticity. Animals were tested weekly for 4 weeks to measure reaching, errors on the gridwalk, locomotion, and vertical exploration. Biotinylated dextran amine was injected into the cortex to label the corticospinal tract. Enriched environments/daily training significantly increased the number and success of left reaches compared to standard housing. Animals also made fewer errors on the gridwalk, a measure of coordinated forelimb function. However, there were no significant improvements in forelimb use during vertical exploration or locomotion. Likewise, rolipram did not improve any of the behaviors tested. Both enriched housing and rolipram increased plasticity of the corticospinal tract rostral to the lesion. These studies indicate that skilled training after a cervical spinal cord injury improves recovery of skilled forelimb use (reaching) and coordinated limb function (gridwalk) but does not improve automatic forelimb function (locomotion and vertical exploration). These studies suggest that rehabilitating forelimb function after spinal cord injury will require separate strategies for descending and segmental pathways. PMID:19317604

Discrete mitochondrial aberrations in the spinal cord of sporadic ALS patients.

PubMed

Delic, Vedad; Kurien, Crupa; Cruz, Josean; Zivkovic, Sandra; Barretta, Jennifer; Thomson, Avery; Hennessey, Daniel; Joseph, Jaheem; Ehrhart, Jared; Willing, Alison E; Bradshaw, Patrick; Garbuzova-Davis, Svitlana

2018-08-01

Amyotrophic lateral sclerosis (ALS) is an adult onset neurodegenerative disease characterized by progressive motor neuron degeneration in the brain and spinal cord leading to muscle atrophy, paralysis, and death. Mitochondrial dysfunction is a major contributor to motor neuron degeneration associated with ALS progression. Mitochondrial abnormalities have been determined in spinal cords of animal disease models and ALS patients. However, molecular mechanisms leading to mitochondrial dysfunction in sporadic ALS (sALS) patients remain unclear. Also, segmental or regional variation in mitochondrial activity in the spinal cord has not been extensively examined in ALS. In our study, the activity of mitochondrial electron transport chain complex IV was examined in post-mortem gray and white matter of the cervical and lumbar spinal cords from male and female sALS patients and controls. Mitochondrial distribution and density in spinal cord motor neurons, lateral funiculus, and capillaries in gray and white matter were analyzed by immunohistochemistry. Results showed that complex IV activity was significantly decreased only in gray matter in both cervical and lumbar spinal cords from ALS patients. In ALS cervical and lumbar spinal cords, significantly increased mitochondrial density and altered distribution were observed in motor neurons, lateral funiculus, and cervical white matter capillaries. Discrete decreased complex IV activity in addition to changes in mitochondria distribution and density determined in the spinal cord in sALS patients are novel findings. These explicit mitochondrial defects in the spinal cord may contribute to ALS pathogenesis and should be considered in development of therapeutic approaches for this disease. © 2018 Wiley Periodicals, Inc.

Cervical helical axis characteristics and its center of rotation during active head and upper arm movements-comparisons of whiplash-associated disorders, non-specific neck pain and asymptomatic individuals.

PubMed

Grip, Helena; Sundelin, Gunnevi; Gerdle, Björn; Stefan Karlsson, J

2008-09-18

The helical axis model can be used to describe translation and rotation of spine segments. The aim of this study was to investigate the cervical helical axis and its center of rotation during fast head movements (side rotation and flexion/extension) and ball catching in patients with non-specific neck pain or pain due to whiplash injury as compared with matched controls. The aim was also to investigate correlations with neck pain intensity. A finite helical axis model with a time-varying window was used. The intersection point of the axis during different movement conditions was calculated. A repeated-measures ANOVA model was used to investigate the cervical helical axis and its rotation center for consecutive levels of 15 degrees during head movement. Irregularities in axis movement were derived using a zero-crossing approach. In addition, head, arm and upper body range of motion and velocity were observed. A general increase of axis irregularity that correlated to pain intensity was observed in the whiplash group. The rotation center was superiorly displaced in the non-specific neck pain group during side rotation, with the same tendency for the whiplash group. During ball catching, an anterior displacement (and a tendency to an inferior displacement) of the center of rotation and slower and more restricted upper body movements implied a changed movement strategy in neck pain patients, possibly as an attempt to stabilize the cervical spine during head movement.

[Recommendations for Diagnosis and Treatment of Fractures of the Ring of Axis].

PubMed

Scholz, Matti; Schleicher, Philipp; Kandziora, Frank; Badke, Andreas; Dreimann, Marc; Gebhard, Harry; Gercek, Erol; Gonschorek, Oliver; Hartensuer, René; Jarvers, Jan-Sven Gilbert; Katscher, Sebastian; Kobbe, Philipp; Koepp, Holger; Korge, Andreas; Matschke, Stefan; Mörk, Sven; Müller, Christian W; Osterhoff, Georg; Pécsi, Ferenc; Pishnamaz, Miguel; Reinhold, Maximilian; Schmeiser, Gregor; Schnake, Klaus John; Schneider, Kristian; Spiegl, Ulrich Josef Albert; Ullrich, Bernhard

2018-06-22

In a consensus process with four sessions in 2017, the working group "upper cervical spine" of the German Society for Orthopaedics and Trauma Surgery (DGOU) formulated "Therapeutic Recommendations for the Diagnosis and Treatment of Upper Cervical Fractures", taking their own experience and the current literature into consideration. The following article describes the recommendations for axis ring fractures (traumatic spondylolysis C2). About 19 to 49% of all cervical spine injuries include the axis vertebra. Traumatic spondylolysis of C2 may include potential discoligamentous instability C2/3. The primary aim of the diagnostic process is to detect the injury and to determine potential disco-ligamentous instability C2/3. For classification purposes, the Josten classification or the modified Effendi classification may be used. The Canadian C-spine rule is recommended for clinical screening for C-spine injuries. CT is the preferred imaging modality and an MRI is needed to determine the integrity of the discoligamentous complex C2/3. Conservative treatment is appropriate in case of stable fractures with intact C2/3 motion segment (Josten type 2 and 2). Patients should be closely monitored, in order to detect secondary dislocation as early as possible. Surgical treatment is recommended in cases of primary severe fracture dislocation or discoligamentous instability C2/3 (Josten 3 and 4) and/or secondary fracture dislocation. Anterior cervical decompression and fusion (ACDF) C2/3 is the treatment of choice. However, in case of facet joint luxation C2/3 with looked facet (Josten 4), a primary posterior approach may be necessary. Georg Thieme Verlag KG Stuttgart · New York.

Contact pressure in the facet joint during sagittal bending of the cadaveric cervical spine.

PubMed

Jaumard, Nicolas V; Bauman, Joel A; Weisshaar, Christine L; Guarino, Benjamin B; Welch, William C; Winkelstein, Beth A

2011-07-01

The facet joint contributes to the normal biomechanical function of the spine by transmitting loads and limiting motions via articular contact. However, little is known about the contact pressure response for this joint. Such information can provide a quantitative measure of the facet joint's local environment. The objective of this study was to measure facet pressure during physiologic bending in the cervical spine, using a joint capsule-sparing technique. Flexion and extension bending moments were applied to six human cadaveric cervical spines. Global motions (C2-T1) were defined using infra-red cameras to track markers on each vertebra. Contact pressure in the C5-C6 facet was also measured using a tip-mounted pressure transducer inserted into the joint space through a hole in the postero-inferior region of the C5 lateral mass. Facet contact pressure increased by 67.6 ± 26.9 kPa under a 2.4 Nm extension moment and decreased by 10.3 ± 9.7 kPa under a 2.7 Nm flexion moment. The mean rotation of the overall cervical specimen motion segments was 9.6 ± 0.8° and was 1.6 ± 0.7° for the C5-C6 joint, respectively, for extension. The change in pressure during extension was linearly related to both the change in moment (51.4 ± 42.6 kPa/Nm) and the change in C5-C6 angle (18.0 ± 108.9 kPa/deg). Contact pressure in the inferior region of the cervical facet joint increases during extension as the articular surfaces come in contact, and decreases in flexion as the joint opens, similar to reports in the lumbar spine despite the difference in facet orientation in those spinal regions. Joint contact pressure is linearly related to both sagittal moment and spinal rotation. Cartilage degeneration and the presence of meniscoids may account for the variation in the pressure profiles measured during physiologic sagittal bending. This study shows that cervical facet contact pressure can be directly measured with minimal disruption to the joint and is the first to provide local pressure values for the cervical joint in a cadaveric model.

Maintaining neutral sagittal cervical alignment after football helmet removal during emergency spine injury management.

PubMed

Decoster, Laura C; Burns, Matthew F; Swartz, Erik E; Murthi, Dinakar S; Hernandez, Adam E; Vailas, James C; Isham, Linda L

2012-04-15

Descriptive laboratory study. To determine whether the placement of padding beneath the occiput after helmet removal is an effective intervention to maintain neutral sagittal cervical spine alignment in a position comparable with the helmeted condition. Current on-field recommendations for managing football athletes with suspected cervical spine injuries call for face mask removal, rather than helmet removal, because the combination of helmet and shoulder pads has been shown to maintain neutral cervical alignment. Therefore, in cases when helmet removal is required, recommendations also call for shoulder pad removal. Because removal of equipment causes motion, any technique that postpones the need to remove the shoulder pads would reduce prehospital motion. Four lateral radiographs of 20 male participants were obtained (age = 23.6 ± 2.7 years). Radiographs of participants wearing shoulder pads and helmet were first obtained. The helmet was removed and radiographs of participants with occipital padding were obtained immediately and 20 minutes later and finally without occipital padding. Cobb angle measurements for C2-C6 vertebral segments were determined by an orthopedic spine surgeon blinded to the study's purpose. Intraobserver reliability was determined using intraclass coefficient analysis. Measurements were analyzed using a 1×4 repeated-measures analysis of variance and post hoc pairwise comparisons with Bonferroni correction. Intraobserver analysis showed excellent reliability (intraclass correlation = 1.0; 95% confidence interval [CI], 0.999-1.0). Repeated-measures analysis of variance detected significant differences (F(3,17) = 13.34; P < 0.001). Pairwise comparisons revealed no differences in cervical alignment (all measurements reported reflect lordosis) when comparing the baseline helmeted condition (10.1° ± 8.7°; 95% CI, 6.0-14.1) with the padded conditions. Measurements taken after removal of occipital padding (14.4° ± 8.1°; 95% CI, 10.6-18.2) demonstrated a significant increase in cervical lordosis compared with the immediate padded measurement (9.5° ± 6.9°; 95% CI, 6.3-12.7; P = 0.011) and the 20-minute padded measurement (6.5° ± 6.8°; 95% CI, 3.4-9.7; P < 0.001). Although face mask removal remains the standard, if it becomes necessary to remove the football helmet in the field, occipital padding (along with full body/head immobilization techniques) may be used to limit cervical lordosis, allowing safe delay of shoulder pad removal.

Comparing cervical spine motion with different halo devices in a cadaveric cervical instability model.

PubMed

DiPaola, Christian P; Sawers, Andrew; Conrad, Bryan P; Horodyski, MaryBeth; DiPaola, Matthew J; Del Rossi, Gianluca; Rechtine, Glenn R

2009-01-15

Biomechanical evaluation of conventional and noninvasive halos in cadaveric C1-C2 and C5-C6 instability models. To compare the ability of a conventional halo and noninvasive halo (NIH) to immobilize the unstable cervical spine at the C1-C2 and C5-C6 levels. Many successful outcomes have been reported in cervical spine injury treatment with the conventional halo (CH); however, complications related to pin sites have been reported. The NIH was designed to overcome these complications. To date, no investigation has compared the biomechanical efficacy of the NIH with that of the CH in restricting three-dimensional cervical spine motion. A global instability was created at the C1-C2 level in 4 cadavers and at C5-C6 in 4 others. Relative motion was measured between the superior and inferior vertebrae during the donning process, execution of the log roll technique, and during the process of sitting up. This testing sequence was followed for all treatment conditions. During the application of the orthoses there was a significant increase in motion at C1-C2 instability and a trend toward increased motion at the C5-C6 instability with CH compared with NIH. In the log roll maneuver, the CH and NIH restrict motion to a similar degree at the C1-C2 instability level, except in frontal plane translation, where CH immobilizes the segment to a greater extent. For the C5-C6 instability the CH provides significantly better immobilization for lateral bending and axial translation. No significant differences were found between the NIH and CH for the sit-up maneuver at either of the levels. Donning of the NIH generates significantly less cervical spine motion than application of the CH. The CH provides superior immobilization for a C5-C6 instability during the log roll maneuver and a C1-C2 instability in the frontal plane during the log-roll maneuver. The CH and NIH immobilize the C1-C2 and C5-C6 instability to a similar degree during the sit-up maneuver.

Environmental and Psychosocial Barriers to and Benefits of Cervical Cancer Screening in Kenya

PubMed Central

Ragan, Kathleen; Lee Smith, Judith; Saraiya, Mona; Aketch, Millicent

2017-01-01

Abstract Background. Cervical cancer is the second most commonly diagnosed cancer in females and is a leading cause of cancer‐related mortality in Kenya; limited cervical cancer screening services may be a factor. Few studies have examined men's and women's perceptions on environmental and psychosocial barriers and benefits related to screening. Materials and Methods. In 2014, 60 women aged 25–49 years and 40 male partners participated in 10 focus groups (6 female and 4 male), in both rural and urban settings (Nairobi and Nyanza, Kenya), to explore perceptions about barriers to and benefits of cervical cancer screening. Focus groups were segmented by sex, language, geographic location, and screening status. Data were transcribed, translated into English, and analyzed by using qualitative software. Results. Participants identified screening as beneficial for initiating provider discussions about cancer but did not report it as a beneficial method for detecting precancers. Perceived screening barriers included access (transportation, cost), spousal approval, stigma, embarrassment during screening, concerns about speculum use causing infertility, fear of residual effects of test results, lack of knowledge, and religious or cultural beliefs. All participants reported concerns with having a male doctor perform screening tests; however, men uniquely reported the young age of a doctor as a barrier. Conclusion. Identifying perceived barriers and benefits among people in low‐ and middle‐income countries is important to successfully implementing emerging screening programs. The novel findings on barriers and benefits from this study can inform the development of targeted community outreach activities, communication strategies, and educational messages for patients, families, and providers. Implications for Practice. This article provides important information for stakeholders in clinical practice and research when assessing knowledge, beliefs, and acceptability of cervical cancer screening and treatment services in low‐ and middle‐resourced countries. Formative research findings provide information that could be used in the development of health interventions, community education messages, and materials. Additionally, this study illuminates the importance of understanding psychosocial barriers and facilitators to cervical cancer screening, community education, and reduction of stigma as important methods of improving prevention programs and increasing rates of screening among women. PMID:28167567

4- and 5-level anterior fusions of the cervical spine: review of literature and clinical results

PubMed Central

Koller, Heiko; Ferraris, Luis; Maier, Oliver; Hitzl, Wolfgang; Metz-Stavenhagen, Peter

2007-01-01

In the future, there will be an increased number of cervical revision surgeries, including 4- and more-levels. But, there is a paucity of literature concerning the geometrical and clinical outcome in these challenging reconstructions. To contribute to current knowledge, we want to share our experience with 4- and 5-level anterior cervical fusions in 26 cases in sight of a critical review of literature. At index procedure, almost 50% of our patients had previous cervical surgeries performed. Besides failed prior surgeries, indications included degenerative multilevel instability and spondylotic myelopathy with cervical kyphosis. An average of 4.1 levels was instrumented and fused using constrained (26.9%) and non-constrained (73.1%) screw-plate systems. At all, four patients had 3-level corpectomies, and three had additional posterior stabilization and fusion. Mean age of patients at index procedure was 54 years with a mean follow-up intervall of 30.9 months. Preoperative lordosis C2-7 was 6.5° in average, which measured a mean of 15.6° at last follow-up. Postoperative lordosis at fusion block was 14.4° in average, and 13.6° at last follow-up. In 34.6% of patients some kind of postoperative change in construct geometry was observed, but without any catastrophic construct failure. There were two delayed unions, but finally union rate was 100% without any need for the Halo device. Eleven patients (42.3%) showed an excellent outcome, twelve good (46.2%), one fair (3.8%), and two poor (7.7%). The study demonstrated that anterior-only instrumentations following segmental decompressions or use of the hybrid technique with discontinuous corpectomies can avoid the need for posterior supplemental surgery in 4- and 5-level surgeries. However, also the review of literature shows that decreased construct rigidity following more than 2-level corpectomies can demand 360° instrumentation and fusion. Concerning construct rigidity and radiolographic course, constrained plates did better than non-constrained ones. The discussion of our results are accompanied by a detailed review of literature, shedding light on the biomechanical challenges in multilevel cervical procedures and suggests conclusions. PMID:17605052

Evaluation of anterior cervical reconstruction with titanium mesh cages versus nano-hydroxyapatite/polyamide66 cages after 1- or 2-level corpectomy for multilevel cervical spondylotic myelopathy: a retrospective study of 117 patients.

PubMed

Zhang, Yuan; Quan, Zhengxue; Zhao, Zenghui; Luo, Xiaoji; Tang, Ke; Li, Jie; Zhou, Xu; Jiang, Dianming

2014-01-01

To retrospectively compare the efficacy of the titanium mesh cage (TMC) and the nano-hydroxyapatite/polyamide66 cage (n-HA/PA66 cage) for 1- or 2-level anterior cervical corpectomy and fusion (ACCF) to treat multilevel cervical spondylotic myelopathy (MCSM). A total of 117 consecutive patients with MCSM who underwent 1- or 2-level ACCF using a TMC or an n-HA/PA66 cage were studied retrospectively at a mean follow-up of 45.28 ± 12.83 months. The patients were divided into four groups according to the level of corpectomy (1- or 2-level corpectomy) and cage type used (TMC or n-HA/PA66 cage). Clinical and radiological parameters were used to evaluate outcomes. At the one-year follow-up, the fusion rate in the n-HA/PA66 group was higher, albeit non-significantly, than that in the TMC group for both 1- and 2-level ACCF, but the fusion rates of the procedures were almost equal at the final follow-up. The incidence of cage subsidence at the final follow-up was significantly higher in the TMC group than in the n-HA/PA66 group for the 1-level ACCF (24% vs. 4%, p = 0.01), and the difference was greater for the 2-level ACCF between the TMC group and the n-HA/PA66 group (38% vs. 5%, p = 0.01). Meanwhile, a much greater loss of fused height was observed in the TMC group compared with the n-HA/PA66 group for both the 1- and 2-level ACCF. All four groups demonstrated increases in C2-C7 Cobb angle and JOA scores and decreases in VAS at the final follow-up compared with preoperative values. The lower incidence of cage subsidence, better maintenance of the height of the fused segment and similar excellent bony fusion indicate that the n-HA/PA66 cage may be a superior alternative to the TMC for cervical reconstruction after cervical corpectomy, in particular for 2-level ACCF.

An automated machine vision system for the histological grading of cervical intraepithelial neoplasia (CIN).

PubMed

Keenan, S J; Diamond, J; McCluggage, W G; Bharucha, H; Thompson, D; Bartels, P H; Hamilton, P W

2000-11-01

The histological grading of cervical intraepithelial neoplasia (CIN) remains subjective, resulting in inter- and intra-observer variation and poor reproducibility in the grading of cervical lesions. This study has attempted to develop an objective grading system using automated machine vision. The architectural features of cervical squamous epithelium are quantitatively analysed using a combination of computerized digital image processing and Delaunay triangulation analysis; 230 images digitally captured from cases previously classified by a gynaecological pathologist included normal cervical squamous epithelium (n=30), koilocytosis (n=46), CIN 1 (n=52), CIN 2 (n=56), and CIN 3 (n=46). Intra- and inter-observer variation had kappa values of 0.502 and 0.415, respectively. A machine vision system was developed in KS400 macro programming language to segment and mark the centres of all nuclei within the epithelium. By object-oriented analysis of image components, the positional information of nuclei was used to construct a Delaunay triangulation mesh. Each mesh was analysed to compute triangle dimensions including the mean triangle area, the mean triangle edge length, and the number of triangles per unit area, giving an individual quantitative profile of measurements for each case. Discriminant analysis of the geometric data revealed the significant discriminatory variables from which a classification score was derived. The scoring system distinguished between normal and CIN 3 in 98.7% of cases and between koilocytosis and CIN 1 in 76.5% of cases, but only 62.3% of the CIN cases were classified into the correct group, with the CIN 2 group showing the highest rate of misclassification. Graphical plots of triangulation data demonstrated the continuum of morphological change from normal squamous epithelium to the highest grade of CIN, with overlapping of the groups originally defined by the pathologists. This study shows that automated location of nuclei in cervical biopsies using computerized image analysis is possible. Analysis of positional information enables quantitative evaluation of architectural features in CIN using Delaunay triangulation meshes, which is effective in the objective classification of CIN. This demonstrates the future potential of automated machine vision systems in diagnostic histopathology. Copyright 2000 John Wiley & Sons, Ltd.

Immediate effects on electromyographic activity and pressure pain thresholds after a cervical manipulation in mechanical neck pain: a randomized controlled trial.

PubMed

de Camargo, Viviane Maduro; Alburquerque-Sendín, Francisco; Bérzin, Fausto; Stefanelli, Vinicius Cobos; de Souza, Daiana P Rodrigues; Fernández-de-las-Peñas, César

2011-05-01

The purpose of this study was to identify the immediate effects of a manipulation of C5/C6 level on electromyography (EMG) of the deltoid muscle and in pressure pain thresholds (PPTs) in patients with mechanical neck pain. Thirty-seven subjects with mechanical neck pain were randomly divided into 2 groups: manipulative group, which received a cervical spine manipulation targeted to C5/C6 segment, and a control group, which did not receive any procedure. Outcomes were EMG data of the deltoid muscle (rest, isometric contraction for 5 or 30 seconds, and isotonic contraction) and PPT over upper trapezius and deltoid muscles and C5 spinous process. They were assessed before and 5 minutes after treatment by a blinded assessor. A 3-way repeated-measures analysis of variance was used to examine the effects of the manipulation. A significant group time interaction for MF at the beginning of isometric contraction for 30 seconds (F = 7.957, P = .006) was also found: the manipulative group experienced a greater increase in MF at the beginning of the isometric contraction than did the control group. A significant group time interaction was also found for root mean square during isometric contraction for 30 seconds (P = .003); however, changes were small. Patients within the manipulative group experienced an increase on PPT over the deltoid (P = .010) and C5 spinous process (P = .025), but not over upper trapezius (P = .776). Manipulation at C5/C6 level in the study participants seemed to increase EMG amplitude signal and fatigue resistance in a nonspinal (deltoid) muscle innervated by the same segment in patients with mechanical neck pain. However, these changes were relative small. An increase on PPT over those tissues innervated by the manipulated segment was also found after the manipulative procedure. Copyright © 2011 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

The Overexpression of TDP-43 Protein in the Neuron and Oligodendrocyte Cells Causes the Progressive Motor Neuron Degeneration in the SOD1 G93A Transgenic Mouse Model of Amyotrophic Lateral Sclerosis.

PubMed

Lu, Yi; Tang, Chunyan; Zhu, Lei; Li, Jiao; Liang, Huiting; Zhang, Jie; Xu, Renshi

2016-01-01

The recent investigation suggested that the TDP-43 protein was closely related to the motor neuron degeneration in amyotrophic lateral sclerosis (ALS), but the pathogenesis contributed to motor neuron degeneration largely remained unknown. Therefore, we detected the alteration of TDP-43 expression and distribution in the adult spinal cord of the SOD1 G93A transgenic mouse model for searching the possible pathogenesis of ALS. We examined the TDP-43 expression and distribution in the different anatomic regions, segments and neural cells in the adult spinal cord at the different stages of the SOD1 wild-type and G93A transgenic model by the fluorescent immunohistochemical technology. We revealed that the amount of TDP-43 positive cell was cervical>lumbar>thoracic segment, that in the ventral horn was more than that in the dorsal horn, a few of TDP-43 protein sparsely expressed and distributed in the other regions, the TDP-43 protein weren't detected in the white matter and the central canal. The TDP-43 protein was mostly expressed and distributed in the nuclear of neuron cells and the cytoplasm of oligodendrocyte cells of the gray matter surrounding the central canal of spinal cord by the granular shape in the SOD1 wild-type and G93A transgenic mice. The amount of TDP-43 positive cell significantly increased at the onset and progression stages of ALS following with the increase of neuron death in spinal cord, particularly in the ventral horn of cervical segment at the progression stage. Our results suggested that the overexpression of TDP-43 protein in the neuron and oligodendrocyte cell causes the progressive motor neuron degeneration in the ALS-like mouse model.

Generation and Development of Paravertebral Ossification in Cervical Artificial Disk Replacement: A Detailed Analytic Report Using Coronal Reconstruction CT.

PubMed

Tian, Wei; Han, Xiao; Liu, Bo; He, Da; Lv, Yanwei; Yue, James

2017-04-01

A retrospective follow-up study and review of images in published papers. To determine whether true heterotopic ossification (HO) occurs in artificial disk replacement (ADR); to evaluate the incidence of paravertebral ossification (PO) and its influence on ADR. HO is typically defined as the abnormal formation of true bone within extraskeletal soft tissues. However, HO in ADR does not fit this definition precisely, as it originates from vertebral body, making it hard to distinguish radiologically from preexisting osteophytes. In this study, the term used for bone formation around ADR is PO. First, all images in the published papers were evaluated as to whether the presented PO in ADR fit the classic definition of HO or osteophytes. Second, we studied 37 consecutive patients who underwent ADR and follow-up for minimum 24 months. The preoperative and follow-up incidence of PO and its influence on range of motion were evaluated using x-ray and computed tomography. All 52 images of PO were found adjacent to the disk in 1 segment rather than entire cervical spine. Fifty (96.2%) of the POs were found to originate from the vertebral body rather than in the soft tissue. A total of 31 patients were included in the follow-up study. No significant difference was found in the incidence of PO between the follow-up and preoperation (61.29% vs. 48.39%, P>0.05). The range of motion of the ADR segment in patients with progressed PO (7.44±4.64 degrees) was significantly lower than that of patients with stable PO grade (12.13±4.42 degrees, P<0.01) at last follow-up. A proportion of HO might in fact be the natural development of preoperative osteophytes, which is unrelated to ADR; the remaining HO might be due to changes in biomechanical environment after surgery, which promotes the grade of osteophytes and affects the segment motion.

Development of the Synarcual in the Elephant Sharks (Holocephali; Chondrichthyes): Implications for Vertebral Formation and Fusion.

PubMed

Johanson, Zerina; Boisvert, Catherine; Maksimenko, Anton; Currie, Peter; Trinajstic, Kate

2015-01-01

The synarcual is a structure incorporating multiple elements of two or more anterior vertebrae of the axial skeleton, forming immediately posterior to the cranium. It has been convergently acquired in the fossil group 'Placodermi', in Chondrichthyes (Holocephali, Batoidea), within the teleost group Syngnathiformes, and to varying degrees in a range of mammalian taxa. In addition, cervical vertebral fusion presents as an abnormal pathology in a variety of human disorders. Vertebrae develop from axially arranged somites, so that fusion could result from a failure of somite segmentation early in development, or from later heterotopic development of intervertebral bone or cartilage. Examination of early developmental stages indicates that in the Batoidea and the 'Placodermi', individual vertebrae developed normally and only later become incorporated into the synarcual, implying regular somite segmentation and vertebral development. Here we show that in the holocephalan Callorhinchus milii, uniform and regular vertebral segmentation also occurs, with anterior individual vertebra developing separately with subsequent fusion into a synarcual. Vertebral elements forming directly behind the synarcual continue to be incorporated into the synarcual through growth. This appears to be a common pattern through the Vertebrata. Research into human disorders, presenting as cervical fusion at birth, focuses on gene misexpression studies in humans and other mammals such as the mouse. However, in chondrichthyans, vertebral fusion represents the normal morphology, moreover, taxa such Leucoraja (Batoidea) and Callorhinchus (Holocephali) are increasingly used as laboratory animals, and the Callorhinchus genome has been sequenced and is available for study. Our observations on synarcual development in three major groups of early jawed vertebrates indicate that fusion involves heterotopic cartilage and perichondral bone/mineralised cartilage developing outside the regular skeleton. We suggest that chondrichthyans have potential as ideal extant models for identifying the genes involved in these processes, for application to human skeletal heterotopic disorders.

Development of the Synarcual in the Elephant Sharks (Holocephali; Chondrichthyes): Implications for Vertebral Formation and Fusion

PubMed Central

Johanson, Zerina; Boisvert, Catherine; Maksimenko, Anton; Currie, Peter; Trinajstic, Kate

2015-01-01

The synarcual is a structure incorporating multiple elements of two or more anterior vertebrae of the axial skeleton, forming immediately posterior to the cranium. It has been convergently acquired in the fossil group ‘Placodermi’, in Chondrichthyes (Holocephali, Batoidea), within the teleost group Syngnathiformes, and to varying degrees in a range of mammalian taxa. In addition, cervical vertebral fusion presents as an abnormal pathology in a variety of human disorders. Vertebrae develop from axially arranged somites, so that fusion could result from a failure of somite segmentation early in development, or from later heterotopic development of intervertebral bone or cartilage. Examination of early developmental stages indicates that in the Batoidea and the ‘Placodermi’, individual vertebrae developed normally and only later become incorporated into the synarcual, implying regular somite segmentation and vertebral development. Here we show that in the holocephalan Callorhinchus milii, uniform and regular vertebral segmentation also occurs, with anterior individual vertebra developing separately with subsequent fusion into a synarcual. Vertebral elements forming directly behind the synarcual continue to be incorporated into the synarcual through growth. This appears to be a common pattern through the Vertebrata. Research into human disorders, presenting as cervical fusion at birth, focuses on gene misexpression studies in humans and other mammals such as the mouse. However, in chondrichthyans, vertebral fusion represents the normal morphology, moreover, taxa such Leucoraja (Batoidea) and Callorhinchus (Holocephali) are increasingly used as laboratory animals, and the Callorhinchus genome has been sequenced and is available for study. Our observations on synarcual development in three major groups of early jawed vertebrates indicate that fusion involves heterotopic cartilage and perichondral bone/mineralised cartilage developing outside the regular skeleton. We suggest that chondrichthyans have potential as ideal extant models for identifying the genes involved in these processes, for application to human skeletal heterotopic disorders. PMID:26339918

Ocular Alterations in a Rare Case of Segmental Neurofibromatosis Type 1 with a Non-Classified Mutational Variant of the NF-1 Gene.

PubMed

Abdolrahimzadeh, Solmaz; Piraino, Domenica Carmen; Plateroti, Rocco; Scuderi, Gianluca; Recupero, Santi Maria

2016-06-01

Neurofibromatosis type 1 (NF-1) is an autsomal dominant disorder which can occasionally result from somatic mosaicism and manifest as segmental forms of the disease. A 37-year-old woman with ascertained NF-1, based on clinical diagnostic criteria and genetic analysis, was referred for ophthalmological evaluation. Genetic analysis, magnetic resonance imaging (MRI), complete ophthalmological examination, and near infrared reflectance (NIR) images at 815 nm of the retina were obtained. Genetic analysis revealed a non-classified mutational variant of the NF-1 gene identified as NM_000267.3:c2084T > C (p.Leu695Pro.T). MRI demonstrated non-symptomatic bilateral optic nerve gliomas. The only cutaneous sign was a subcutaneous neurofibroma of the posterior cervical region. Slit-lamp examination showed bilateral Lisch nodules. NIR images of the retina did not show any choroidal hamartomas. We report a rare case of segmental neurofibromatosis with a non-classified mutational variant of the NF-1 gene described in only one previous case in the literature. The patient presented with clinical features of NF-1 localized to the head and neck region, compatible with diagnosis of segmental NF-1. Interestingly, ocular manifestations included bilateral optic nerve gliomas and Lisch nodules, but no choroidal hamartomas.

Deformable anatomical templates for brachytherapy treatment planning in radiotherapy of cervical cancer

NASA Astrophysics Data System (ADS)

Christensen, Gary E.; Williamson, Jeffrey F.; Chao, K. S. C.; Miller, Michael I.; So, F. B.; Vannier, Michael W.

1997-10-01

This paper describes a new method to register serial, volumetric x-ray computed tomography (CT) data sets for tracking soft-tissue deformation caused by insertion of intracavity brachytherapy applicators to treat cervical cancer. 3D CT scans collected from the same patient with and without a brachytherapy applicator are registered to aid in computation of the radiation dose to tumor and normal tissue. The 3D CT image volume of pelvic anatomy with the applicator. Initial registration is accomplished by rigid alignment of the pelvic bones and non-rigid alignment of gray scale CT data and hand segmentations of the vagina, cervix, bladder, and rectum. A viscous fluid transformation model is used for non-rigid registration to allow for local, non-linear registration of the vagina, cervix, bladder, and rectum without disturbing the rigid registration of the bony pelvis and adjacent structures. Results are presented in which two 3D CT data sets of the same patient - imaged with and without a brachytherapy applicator - are registered.

Level-dependent coronal and axial moment-rotation corridors of degeneration-free cervical spines in lateral flexion.

PubMed

Yoganandan, Narayan; Pintar, Frank A; Stemper, Brian D; Wolfla, Christopher E; Shender, Barry S; Paskoff, Glenn

2007-05-01

Aging, trauma, or degeneration can affect intervertebral kinematics. While in vivo studies can determine motions, moments are not easily quantified. Previous in vitro studies on the cervical spine have largely used specimens from older individuals with varying levels of degeneration and have shown that moment-rotation responses under lateral bending do not vary significantly by spinal level. The objective of the present in vitro biomechanical study was, therefore, to determine the coronal and axial moment-rotation responses of degeneration-free, normal, intact human cadaveric cervicothoracic spinal columns under the lateral bending mode. Nine human cadaveric cervical columns from C2 to T1 were fixed at both ends. The donors had ranged from twenty-three to forty-four years old (mean, thirty-four years) at the time of death. Retroreflective targets were inserted into each vertebra to obtain rotational kinematics in the coronal and axial planes. The specimens were subjected to pure lateral bending moment with use of established techniques. The range-of-motion and neutral zone metrics for the coronal and axial rotation components were determined at each level of the spinal column and were evaluated statistically. Statistical analysis indicated that the two metrics were level-dependent (p < 0.05). Coronal motions were significantly greater (p < 0.05) than axial motions. Moment-rotation responses were nonlinear for both coronal and axial rotation components under lateral bending moments. Each segmental curve for both rotation components was well represented by a logarithmic function (R(2) > 0.95). Range-of-motion metrics compared favorably with those of in vivo investigations. Coronal and axial motions of degeneration-free cervical spinal columns under lateral bending showed substantially different level-dependent responses. The presentation of moment-rotation corridors for both metrics forms a normative dataset for the degeneration-free cervical spines.

Does location of rotation center in artificial disc affect cervical biomechanics?

PubMed

Mo, Zhongjun; Zhao, Yanbin; Du, Chengfei; Sun, Yu; Zhang, Ming; Fan, Yubo

2015-04-15

A 3-dimensional finite element investigation. To compare the biomechanical performances of different rotation centers (RCs) in the prevalent artificial cervical discs. Various configurations are applied in artificial discs. Design parameters may influence the biomechanics of implanted spine. The RC is a primary variation in the popular artificial discs. Implantation of 5 prostheses was simulated at C5-C6 on the basis of a validated finite element cervical model (C3-C7). The prostheses included ball-in-socket design with a fixed RC located on the inferior endplate (BS-FI) and on the superior endplate (BS-FS), with a mobile RC at the inferior endplate (BS-MI), dual articulation with a mobile RC between the endplates (DA-M), and sliding articulation with various RCs (SA-V). The spinal motions in flexion and extension served as a displacement loading at the C3 vertebrae. Total disc replacements reduced extension moment. The ball-in-socket designs required less flexion moment, whereas the flexion stiffness of the spines with DA-M and SA-V was similar to that of the healthy model. The contributions of the implanted level to the global motions increased in the total disc replacements, except in the SA-V and DA-M models (in flexion). Ball-in-socket designs produced severe stress distributions in facet cartilage, whereas DA-M and SA-V produced more severe stress distribution on the bone-implant interface. Cervical stability was extremely affected in extension and partially affected in flexion by total disc replacement. With the prostheses with mobile RC, cervical curvature was readjusted under a low follower load. The SA-V and BS-FS designs exhibited better performances in the entire segmental stiffness and in the stability of the operative level than the BS-MI and BS-FI designs in flexion. The 5 designs demonstrated varying advantages relative to the stress distribution in the facet cartilages and on the bone-implant interface. 5.

Finite Element Analysis of Influence of Axial Position of Center of Rotation of a Cervical Total Disc Replacement on Biomechanical Parameters: Simulated 2-Level Replacement Based on a Validated Model.

PubMed

Li, Yang; Zhang, Zhenjun; Liao, Zhenhua; Mo, Zhongjun; Liu, Weiqiang

2017-10-01

Finite element models have been widely used to predict biomechanical parameters of the cervical spine. Previous studies investigated the influence of position of rotational centers of prostheses on cervical biomechanical parameters after 1-level total disc replacement. The purpose of this study was to explore the effects of axial position of rotational centers of prostheses on cervical biomechanics after 2-level total disc replacement. A validated finite element model of C3-C7 segments and 2 prostheses, including the rotational center located at the superior endplate (SE) and inferior endplate (IE), was developed. Four total disc replacement models were used: 1) IE inserted at C4-C5 disc space and IE inserted at C5-C6 disc space (IE-IE), 2) IE-SE, 3) SE-IE, and 4) SE-SE. All models were subjected to displacement control combined with a 50 N follower load to simulate flexion and extension motions in the sagittal plane. For each case, biomechanical parameters, including predicted moments, range of rotation at each level, facet joint stress, and von Mises stress on the ultra-high-molecular-weight polyethylene core of the prostheses, were calculated. The SE-IE model resulted in significantly lower stress at the cartilage level during extension and at the ultra-high-molecular-weight polyethylene cores when compared with the SE-SE construct and did not generate hypermotion at the C4-C5 level compared with the IE-SE and IE-IE constructs. Based on the present analysis, the SE-IE construct is recommended for treating cervical disease at the C4-C6 level. This study may provide a useful model to inform clinical operations. Copyright © 2017 Elsevier Inc. All rights reserved.

Anterior Cervical Fusion with Stand-alone Trabecular Metal Cages to Treat Cervical Myelopathy Caused by Degenerative Disk Disease. Observations in 88 Cases with Minimum 12-month Follow-up.

PubMed

Mastronardi, Luciano; Roperto, Raffaelino; Cacciotti, Guglielmo; Calvosa, Francesco

2018-06-14

 Anterior cervical fusion (ACF) with autologous bone was reported > 50 years ago. The continuous development of materials with elastic properties close to that of the cortical bone improves induction of osteogenesis and simplifies the technique of interbody fusion. To determine the safety and efficiency of stand-alone trabecular metal (TM) (or porous tantalum) cages for ACF, we performed a retrospective analysis of 88 consecutive patients with one-level or two-level degenerative disk disease (DDD) causing cervical myelopathy treated by interbody fusion with stand-alone TM cages.  During a 65-month period, 88 consecutive patients had ACF at 105 levels between C3 and C7. All surgeries involved one- or two-segmental DDD producing mild or severe cervical spine myelopathy, in 31 patients (35.2%), associated with unilateral or bilateral radiculopathy. We implanted all disk spaces with unfilled TM trapezoidal cages (Zimmer Biomet Spine, Broomfield, Colorado, United States).  At a mean follow-up of 31 months (range: 12-65 months), 95.4% of patients had a good to excellent outcome, with subjective and objective improvement of myelopathy; the result was fair in two and poor in two other patients. Radicular pain and/or any deficits disappeared in 84 patients (95.4%) complaining of preoperative myeloradiculopathy. The fusion rate was 68.2% at 6 months and 100% at 1 year. Device fragmentation was never observed. In two cases, a second operation with removal of TM cages, corpectomy, expansion cages, and plating was necessary.  TM cages appear to be safe and efficient for ACF in DDD patients with myelopathy. To confirm our preliminary impressions, larger studies with long-term follow-up are necessary. Georg Thieme Verlag KG Stuttgart · New York.

Does the Level of Cervical Disc Herniation Surgery Affect Performance-based Outcomes in National Football League Athletes?

PubMed

Mai, Harry T; Burgmeier, Robert J; Mitchell, Sean M; Hecht, Andrew C; Maroon, Joseph C; Nuber, Gordon W; Hsu, Wellington K

2016-12-01

Retrospective cohort study. The aim of this study was to determine whether the level of a cervical disc herniation (CDH) procedure will uniquely impact performance-based outcomes in elite athletes of the National Football League (NFL). Comparative assessments of postsurgical outcomes in NFL athletes with CDH at different levels are unknown. Further, the surgical decision-making for these types of injuries in professional football athletes remains controversial. NFL players with a CDH injury at a definitive cervical level were identified through a review of publicly available archives. Injuries were divided into upper- (C2-C4) and lower-level (C4-T1) CDH. The impact on player outcomes was determined by comparing return to play statistics and calculating a "Performance Score" for each player on the basis of pertinent statistical data, both before and after surgery. A total of 40 NFL athletes met inclusion criteria. In the upper-level group, 10 of 15 (66.6%) players successfully returned to play an average of 44.6 games over 2.6 years. The lower-level cohort had 18 of 25 (72%) players return to play with an average of 44.1 games over 3.1 years. There was no significant difference in the rate of return to play (P = 0.71). Postsurgical performance scores of the upper and lower-level groups were 1.47 vs. 0.69 respectively, with no significant difference between these groups (P = 0.06). Adjacent segment disease requiring reoperation occurred in 10% of anterior cervical discectomy and fusion patients. In 50% of foraminotomy patients, a subsequent fusion was required. A uniquely high percentage of upper-level disc herniations develop in NFL athletes, and although CDH injuries present career threatening implications, an upper-level CDH does not preclude a player from successfully returning to play at a competitive level. In fact, these athletes showed comparable postsurgical performance to those athletes who underwent CDH procedures at lower cervical levels. 4.

Difference of the seismic structure between the Hyuga-nada and the Nankai seismogenic segments

NASA Astrophysics Data System (ADS)

Yamamoto, Y.; Obana, K.; Takahashi, T.; Nakanishi, A.; Kodaira, S.; Kaneda, Y.

2010-12-01

In the Nankai Trough, three major seismogenic zones of megathrust earthquake exist (Tokai, Tonankai and Nankai earthquake regions). The Hyuga-nada region was distinguished from these seismogenic zones because of the lack of megathrust earthquake. In the Hyuga-nada region, interplate earthquakes of M~7 occur repeatedly at intervals of about 20 years whereas no megathrust (M > 8) earthquakes had been recognized up to now. However, recent studies show the possibility of simultaneous rupture of the Tokai, Tonankai, Nankai and Hyuga-nada segments was also pointed out [e.g., Hori et al., 2009 AOGS]. To understand the possibility of seismic linkage of Nankai and Hyuga-nada segments, Japan Agency for Marine-Earth Science and Technology has been carried out a wide-angle active source survey and local seismic observation in the western end of the Nankai seismogenic zone, as a part of Research concerning Interaction Between the Tokai, Tonankai and Nankai Earthquakes' funded by Ministry of Education, Culture, Sports, Science and Technology, Japan. Nakanishi et al [2009, AGU] showed that subducting Philippine Sea Plate can be divided into three zones and there is the zone of the thin oceanic crust of the subducting Philippine Sea Plate between Nankai segment and Kyushu-Palau Ridge segment by analyzing of the active source survey. Deep structure of the subducting slab is also important to consider the possibility of the seismic linkage and the location of the boundary among three zones described above. To obtain the deep seismic image, we performed a three-dimensional seismic tomography using the local seismic data recorded on 158 ocean bottom seismographs and 105 land seismic stations. From these data, we could detect 1141 earthquakes in the Hyuga-nada region. From the result of hypocenter relocation, microseismicity near the trough axis is active on the western part of the ‘thin oceanic crust’, whereas inactive on the eastern part. Besides, velocity structure of the uppermost part of the subducting slab mantle shows spatial heterogeneities. In the thin oceanic crust zone, high velocity slab mantle is imaged from near the trough to coastline. On the other hands, there is low velocity zone in the slab mantle near the trough axis in the Kyusyu-Palau Ridge segment. This low velocity zone may be related to the location of the eastern end of subducted Kyusyu-Palau Ridge.

The Correlation between Insertion Depth of Prodisc-C Artificial Disc and Postoperative Kyphotic Deformity: Clinical Importance of Insertion Depth of Artificial Disc.

PubMed

Lee, Do-Youl; Kim, Se-Hoon; Suh, Jung-Keun; Cho, Tai-Hyoung; Chung, Yong-Gu

2012-09-01

This study was designed to investigate the correlation between insertion depth of artificial disc and postoperative kyphotic deformity after Prodisc-C total disc replacement surgery, and the range of artificial disc insertion depth which is effective in preventing postoperative whole cervical or segmental kyphotic deformity. A retrospective radiological analysis was performed in 50 patients who had undergone single level total disc replacement surgery. Records were reviewed to obtain demographic data. Preoperative and postoperative radiographs were assessed to determine C2-7 Cobb's angle and segmental angle and to investigate postoperative kyphotic deformity. A formula was introduced to calculate insertion depth of Prodisc-C artificial disc. Statistical analysis was performed to search the correlation between insertion depth of Prodisc-C artificial disc and postoperative kyphotic deformity, and to estimate insertion depth of Prodisc-C artificial disc to prevent postoperative kyphotic deformity. In this study no significant statistical correlation was observed between insertion depth of Prodisc-C artificial disc and postoperative kyphotic deformity regarding C2-7 Cobb's angle. Statistical correlation between insertion depth of Prodisc-C artificial disc and postoperative kyphotic deformity was observed regarding segmental angle (p<0.05). It failed to estimate proper insertion depth of Prodisc-C artificial disc effective in preventing postoperative kyphotic deformity. Postoperative segmental kyphotic deformity is associated with insertion depth of Prodisc-C artificial disc. Anterior located artificial disc leads to lordotic segmental angle and posterior located artificial disc leads to kyphotic segmental angle postoperatively. But C2-7 Cobb's angle is not affected by artificial disc location after the surgery.

Current and future medical treatment in primary dystonia

PubMed Central

Delnooz, Cathérine C.S.

2012-01-01

Dystonia is a hyperkinetic movement disorder, characterized by involuntary and sustained contractions of opposing muscles causing twisting movements and abnormal postures. It is often a disabling disorder that has a significant impact on physical and psychosocial wellbeing. The medical therapeutic armamentarium used in practice is quite extensive, but for many of these interventions formal proof of efficacy is lacking. Exceptions are the use of botulinum toxin in patients with cervical dystonia, some forms of cranial dystonia (in particular, blepharospasm) and writer’s cramp; deep brain stimulation of the pallidum in generalized and segmental dystonia; and high-dose trihexyphenidyl in young patients with segmental and generalized dystonia. In order to move this field forward, we not only need better trials that examine the effect of current treatment interventions, but also a further understanding of the pathophysiology of dystonia as a first step to design and test new therapies that are targeted at the underlying biologic and neurophysiologic mechanisms. PMID:22783371

Multifocal Spinal Cord Nephroblastoma in a Dog.

PubMed

Henker, L C; Bianchi, R M; Vargas, T P; de Oliveira, E C; Driemeier, D; Pavarini, S P

2018-01-01

A 1-year-old male American pit bull terrier was presented with a history of proprioceptive deficits and mild lameness of the right hindlimb, which progressed after 5 months to paraparesis, culminating in tetraparesis after 2 weeks. Necropsy findings were limited to the spinal cord and consisted of multiple, intradural, extramedullary, slightly red masses which produced segmental areas of medullary swelling located in the cervical intumescence, thoracolumbar column, sacral segment and cauda equina. Histological evaluation revealed a tumour, composed of epithelial, stromal and blastemal cells, with structures resembling tubules, acini and embryonic glomeruli. Immunohistochemical labelling for vimentin, cytokeratin and S100 was positive for the stromal, epithelial and blastemal cells, respectively. A final diagnosis of multifocal spinal cord nephroblastoma was established. This is the first report of such a tumour showing concomitant involvement of the cervicothoracic, thoracolumbar, sacral and cauda equina areas of the spinal cord. Copyright © 2017 Elsevier Ltd. All rights reserved.

Axonal trajectories of the nucleus reticularis gigantocellularis neurons in the C2-C3 segments in cats.

PubMed

Sasaki, S; Iwamoto, Y

1999-04-02

Axonal trajectories in the C2-C3 segments of the nucleus reticularis gigantocellularis neurons projecting to the lower cervical cord (C-RSNs) and excited monosynaptically from cortico- and tectofugal fibers were studied by mapping thresholds of antidromic excitation and intra-axonal staining in cats. The C-RSNs descended in various sites of the spinal funiculi, and the projection area of individual cells varied with the funicular location of the stem axon. C-RSNs descending in the ventrolateral funiculus (inRSNs) projected mainly to lamina VIII-IX, those descending in the lateral funiculus (IRSNs) mainly to laminae VI-VIII, and those descending in the contralateral funiculus (coRSNs) chiefly to laminae VIII-IX on that side. It is suggested that inRSNs and coRSNs mediate disynaptic effects from cortico- and tectofugal fibers to dorsal neck motoneurons bilaterally.

Seasonal critical concentration and relationships of uppermost fully expanded leaf phosphorus and potassium status with biomass and yield traits at maturity in soybean

USDA-ARS?s Scientific Manuscript database

Analysis of uppermost fully expanded leaves is useful to detect deficiency of mineral nutrients such as phosphorus (P) and potassium (K) in soybean. Although, the leaf P or K status aids in fertilizer management, information on their seasonal association with the growth and yield traits at maturity ...

[Significance of revision of the occupational illness legislation for evaluating intervertebral disk damage].

PubMed

Weber, M; Morgenthaler, M

1997-01-01

Are there any radiological criterions which are able to indicate the profession related disease No. 2108? The medical documents and x-rays of the whole spine of 390 back pain patients who applied for a profession related disease of the spine were evaluated. Those patients who fulfilled the professional claims for acknowledgement of the profession related disease were compared to those who didn't fulfill these conditions. Concerning the segmental alterations of the cervical and the lumbal spine specific allocation frequencies were found. The dominance of L3/4 in the comparison group was conspicuous. Looking at the allocation frequencies of the cervical and lumbal disc alterations in view of affection heaviness it was obvious, that the predominating slight alterations mainly were located in the central parts of the cervical and the lumbal spine whereas bad alterations mainly were found in the lower parts. Regarding this matter test and comparison groups behaved the same way. Looking at the allocation frequencies concerning single respectively multiple alterations it was found that in the comparison group single respectively bisegmentale alterations could be recognized even in duplicate than in the test group in which the multiple alterations were dominant. The comparison of the cervical and the lumbal spine regarding chondrotic? spondylotic, slight and bad alterations in all mentioned features the next deeper located segment was affected particularly in the test group. Therefore a distal shift of the chondrotic alterations could be recognized. In case of the spondylotic affections it was the other way round: a cranial shift was conspicuous. After doing heavy labour for years only a few isolated multiple affections of the lumbal spine are found. On the strength of this fact the proof of exclusively in the lumbal spine located alterations doesn't allow the acknowledgement of a profession related disease. However, a distal shift of osteochondrotic alterations respectively a cranial shift of spondylotic affections in the lumbal spine is suspicous for being job-related. L3/4 takes a very special place in the differential diagnosis of profession related disease of the spine. In the test group this part of the lumbal spine showed bad alterations much more frequent. The affection of L3/4 pleads against a considerable participation of mechanical influences and therefore against a profession related disease. Singular or bisegmental disc affections are out of question for being a profession related disease because these alterations are seen much more frequent in the comparison than in the test group.

Hybrid Decompression Technique Versus Anterior Cervical Corpectomy and Fusion for Treating Multilevel Cervical Spondylotic Myelopathy: Which One Is Better?

PubMed

Liu, Jia-Ming; Peng, Hong-Wei; Liu, Zhi-Li; Long, Xin-Hua; Yu, Yan-Qing; Huang, Shan-Hu

2015-12-01

The hybrid decompression technique (corpectomy combined with discectomy) and anterior cervical corpectomy with fusion (ACCF) both provide good neurological recovery and disease stabilization for the treatment of multilevel cervical spondylotic myelopathy (CSM). However, no single study has been large enough to determine definitively which one is superior for this condition. A meta-analysis was conducted to compare the clinical efficacy and safety of the hybrid decompression technique versus ACCF for the treatment of multilevel CSM. Electronic databases such as PubMed, MEDLINE, EMBASE, Google Scholar, and the Cochrane Library were selected to search for potentially relevant trials up to April 2015 that compared the outcomes of the hybrid technique with ACCF for the treatment of multilevel CSM. Data extraction and quality assessment were performed according to Cochrane Collaboration guidelines. The outcome assessments were duration of surgery, blood loss, Cobb angle of C2-C7, segment angle, fusion rate, Japanese Orthopedics Association score, Neck Disability Index, and complications. The results were expressed as the odds ratio (OR) for dichotomous outcomes and the mean difference (MD) for continuous outcomes with a 95% confidence interval (CI). Five controlled clinical trials published between 2009 and 2013, involving 356 patients (hybrid, 196; ACCF, 160) with 3- or 4-level CSM were retrieved in this study. Overall, there were significant differences between the 2 treatment groups for blood loss (MD = -38.69, 95% CI = -54.62 to -22.76, P < 0.01), fusion rate (OR = 2.56, 95% CI = 1.11 to 5.93, P = 0.03), and complications (OR = 0.25, 95% CI = 0.15 to 0.43, P < 0.01). However, no significant differences were found for duration of surgery (MD = -4.50, 95% CI = -22.902 to 13.91, P = 0.63), Cobb angle of C2-C7 after surgery (MD = 3.32, 95% CI = -3.72 to 10.37, P = 0.35), segment angle after surgery (MD = 2.87, 95% CI = -2.47 to 8.21, P = 0.29), Japanese Orthopedics Association score (MD = -0.07, 95% CI = -0.36 to 0.22, P = 0.62), or Neck Disability Index (MD = -0.86, 95% CI = -3.26 to 1.54, P = 0.48). Based on this meta-analysis, both the hybrid technique and ACCF can achieve good results for CSM. However, the hybrid technique is associated with significantly less blood loss, complications, and a higher fusion rate than ACCF. Copyright © 2015 Elsevier Inc. All rights reserved.

The Uppermost Surface of the Moon

NASA Technical Reports Server (NTRS)

Noble, Sarah K.

2009-01-01

The Ap16 Clam shell Sampling Devices (CSSDs) were designed to sample the uppermost surface of lunar soil. The two devices used beta cloth (69003) and velvet (69004) to collect soil from the top 100 and 500 micrometers of the soil, respectively. Due to the difficulty of the sampling method, little material was collected and as a result little research has been done on these samples. Initial studies attempted to look at the material which had fallen off of the fabrics and was subsequently collected from inside the sample containers. However, this material was highly fractionated and did not provide an adequate picture of the uppermost surface. Recently, samples were obtained directly from the beta cloth using carbon tape. While still fractionated, these samples provide a unique glimpse into the undisturbed soil exposed at the lunar surface.

Trend Extraction of Understanding Degree of Classes through Analyses of Questionnaires on Teaching Skills and the Uppermost Important Points

NASA Astrophysics Data System (ADS)

Koike, Katsuaki; Mori, Kazuya; Yamao, Toshitaka; Fujimi, Toshio

As an activity of one working group for the Good Practice at Kumamoto Univ., we proposed a questionnaire survey on understanding degree of the uppermost important points of each class in addition to the usual class-evaluation questionnaire. Each class lists three uppermost important points which are essential to understand the class contents. The understanding degree is classified into four levels ; full, most, insufficient, and not at all understandings. By analyzing the replies to 124 classes in the 2008 school year with a regression model, the understanding degrees of the bachelor students of the faculty of engineering were clarified to be affected meaningfully by degree of difficulty, effectiveness of audiovisual aids, self-study time, and attendance to class.

Compositional mantle layering revealed by slab stagnation at ~1000-km depth

PubMed Central

Ballmer, Maxim D.; Schmerr, Nicholas C.; Nakagawa, Takashi; Ritsema, Jeroen

2015-01-01

Improved constraints on lower-mantle composition are fundamental to understand the accretion, differentiation, and thermochemical evolution of our planet. Cosmochemical arguments indicate that lower-mantle rocks may be enriched in Si relative to upper-mantle pyrolite, whereas seismic tomography images suggest whole-mantle convection and hence appear to imply efficient mantle mixing. This study reconciles cosmochemical and geophysical constraints using the stagnation of some slab segments at ~1000-km depth as the key observation. Through numerical modeling of subduction, we show that lower-mantle enrichment in intrinsically dense basaltic lithologies can render slabs neutrally buoyant in the uppermost lower mantle. Slab stagnation (at depths of ~660 and ~1000 km) and unimpeded slab sinking to great depths can coexist if the basalt fraction is ~8% higher in the lower mantle than in the upper mantle, equivalent to a lower-mantle Mg/Si of ~1.18. Global-scale geodynamic models demonstrate that such a moderate compositional gradient across the mantle can persist can in the presence of whole-mantle convection. PMID:26824060

Radiographic predictors for the development of myelopathy in patients with ossification of the posterior longitudinal ligament: a multicenter cohort study.

PubMed

Matsunaga, Shunji; Nakamura, Kozo; Seichi, Atsushi; Yokoyama, Toru; Toh, Satoshi; Ichimura, Shoichi; Satomi, Kazuhiko; Endo, Kenji; Yamamoto, Kengo; Kato, Yoshiharu; Ito, Tatsuo; Tokuhashi, Yasuaki; Uchida, Kenzo; Baba, Hisatoshi; Kawahara, Norio; Tomita, Katsuro; Matsuyama, Yukihiro; Ishiguro, Naoki; Iwasaki, Motoki; Yoshikawa, Hideki; Yonenobu, Kazuo; Kawakami, Mamoru; Yoshida, Munehito; Inoue, Shinsuke; Tani, Toshikazu; Kaneko, Kazuo; Taguchi, Toshihiko; Imakiire, Takanori; Komiya, Setsuro

2008-11-15

A multicenter cohort study was performed retrospectively. To identify radiographic predictors for the development of myelopathy in patients with ossification of the posterior longitudinal ligaments (OPLL). The pathomechanism of myelopathy in the OPLL remains unknown. Some patients with large OPLL have not exhibited myelopathy for a long periods of time. Predicting the course of future neurologic deterioration in asyptomatic patients with OPLL is difficult at their initial visit. A total of 156 OPLL patients from 16 spine institutes with an average of 10.3 years of follow-up were reviewed. Subjects underwent a plain roentgenogram, computed tomography (CT), and magnetic resonance imaging of the cervical spine during the follow-up. The trauma history of the cervical spine, maximum percentage of spinal canal stenosis in a plain roentgenogram and CT, range of motion of the cervical spine, and axial ossified pattern in magnetic resonance imaging or CT were reviewed in relation to the existence of myelopathy. All 39 patients with greater than 60% spinal canal stenosis on the plain roentgenogram exhibited myelopathy. Of 117 patients with less than 60% spinal canal stenosis, 57 (49%) patients exhibited myelopathy. The range of motion of the cervical spine was significantly larger in patients with myelopathy than in those of without it. The axial ossified pattern could be classified into 2 types: a central type and a lateral deviated type. The incidence of myelopathy in patients with less than 60% spinal canal stenosis was significantly higher in the lateral deviated-type group than in the central-type group. Fifteen patients of 156 subjects developed trauma-induced myelopathy. Of the 15 patients, 13 had mixed-type OPLL and 2 had segmental-type OPLL. Static and dynamic factors were related to the development of myelopathy in OPLL.

Effects of Overground Locomotor Training on Walking Performance in Chronic Cervical Motor Incomplete Spinal Cord Injury: A Pilot Study.

PubMed

Gollie, Jared M; Guccione, Andrew A; Panza, Gino S; Jo, Peter Y; Herrick, Jeffrey E

2017-06-01

To determine the effects of a novel overground locomotor training program on walking performance in people with chronic cervical motor incomplete spinal cord injury (iSCI). Before-after pilot study. Human performance research laboratory. Adults (N=6, age >18y) with chronic cervical iSCI with American Spinal Injury Association Impairment Scale grades C and D. Overground locomotor training included two 90-minute sessions per week for 12 to 15 weeks. Training sessions alternated between uniplanar and multiplanar stepping patterns. Each session was comprised of 5 segments: joint mobility, volitional muscle activation, task isolation, task integration, and activity rehearsal. Overground walking speed, oxygen consumption (V˙o 2 ), and carbon dioxide production (V˙co 2 ). Overground locomotor training increased overground walking speed (.36±.20 vs .51±.24 m/s, P<.001, d=.68). Significant decreases in V˙o 2 (6.6±1.3 vs 5.7±1.4mL·kg·min, P=.038, d=.67) and V˙co 2 (753.1±125.5 vs 670.7±120.3mL/min, P=.036, d=.67) during self-selected constant work rate treadmill walking were also noted after training. The overground locomotor training program used in this pilot study is feasible and improved both overground walking speed and walking economy in a small sample of people with chronic cervical iSCI. Future studies are necessary to establish the efficacy of this overground locomotor training program and to differentiate among potential mechanisms contributing to enhanced walking performance in people with iSCI after overground locomotor training. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Push-out bond strengths of two fiber post types bonded with different dentin bonding agents.

PubMed

Topcu, Fulya Toksoy; Erdemir, Ugur; Sahinkesen, Gunes; Mumcu, Emre; Yildiz, Esra; Uslan, Ibrahim

2010-05-01

The aim of this study was to evaluate the regional push-out bond strengths for two fiber-reinforced post types using three different dentin bonding agents. Sixty single-rooted extracted human first premolar teeth were sectioned below the cemento-enamel junction, and the roots were endodontically treated. Following standardized post space preparations, the roots were divided into two fiber-post groups (Glassix and Carbopost), and further divided into three subgroups of 10 specimens each for the bonding systems self-etching dentin bonding agents (Clearfil SE Bond and Optibond all-in-one), and total-etching dentin bonding agent (XP Bond). A dual-cure resin luting cement (Maxcem) was then placed in the post spaces and posts were then seated into the root canals polymerized through the cervical portion. The roots were then cut into 3-mm thick sections. Push-out tests were performed at a crosshead speed of 0.5 mm/min. The data were analyzed with multivariate ANOVA (alpha = 0.05). The morphology of interface between different dentin bonding agents from the cervical sections were analyzed with SEM. Glass fiber-reinforced posts demonstrated significantly higher push-out bond strengths than carbon fiber-reinforced posts (p < 0.001). Bond strength values decreased significantly from the cervical to the apical root canal regions (p < 0.001). Self-etching dentin adhesive Clearfil SE Bond and total-etching dentin adhesive XP Bond demonstrated similar bond strengths values and this was significantly higher compared with the Optibond all-in-one in cervical root canal region. In conclusion, in all root segments, the glass fiber-reinforced posts provided significantly increased post retention than the carbon fiber-reinforced posts, regardless of the adhesive used. (c) 2010 Wiley Periodicals, Inc.

Human Glial-Restricted Progenitor Transplantation into Cervical Spinal Cord of the SOD1G93A Mouse Model of ALS

PubMed Central

Lepore, Angelo C.; O'Donnell, John; Kim, Andrew S.; Williams, Timothy; Tuteja, Alicia; Rao, Mahendra S.; Kelley, Linda L.; Campanelli, James T.; Maragakis, Nicholas J.

2011-01-01

Cellular abnormalities are not limited to motor neurons in amyotrophic lateral sclerosis (ALS). There are numerous observations of astrocyte dysfunction in both humans with ALS and in SOD1G93A rodents, a widely studied ALS model. The present study therapeutically targeted astrocyte replacement in this model via transplantation of human Glial-Restricted Progenitors (hGRPs), lineage-restricted progenitors derived from human fetal neural tissue. Our previous findings demonstrated that transplantation of rodent-derived GRPs into cervical spinal cord ventral gray matter (in order to target therapy to diaphragmatic function) resulted in therapeutic efficacy in the SOD1G93A rat. Those findings demonstrated the feasibility and efficacy of transplantation-based astrocyte replacement for ALS, and also show that targeted multi-segmental cell delivery to cervical spinal cord is a promising therapeutic strategy, particularly because of its relevance to addressing respiratory compromise associated with ALS. The present study investigated the safety and in vivo survival, distribution, differentiation, and potential efficacy of hGRPs in the SOD1G93A mouse. hGRP transplants robustly survived and migrated in both gray and white matter and differentiated into astrocytes in SOD1G93A mice spinal cord, despite ongoing disease progression. However, cervical spinal cord transplants did not result in motor neuron protection or any therapeutic benefits on functional outcome measures. This study provides an in vivo characterization of this glial progenitor cell and provides a foundation for understanding their capacity for survival, integration within host tissues, differentiation into glial subtypes, migration, and lack of toxicity or tumor formation. PMID:21998733

Imaging of Herniated Discs of the Cervical Spine: Inter-Modality Differences between 64-Slice Multidetector CT and 1.5-T MRI

PubMed Central

Yi, Ji Sook; Han, Jong Kyu; Kim, Hyun-Joo

2015-01-01

Objective To assess inter-modality variability when evaluating cervical intervertebral disc herniation using 64-slice multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI). Materials and Methods Three musculoskeletal radiologists independently reviewed cervical spine 1.5-T MRI and 64-slice MDCT data on C2-3 though C6-7 of 51 patients in the context of intervertebral disc herniation. Interobserver and inter-modality agreements were expressed as unweighted kappa values. Weighted kappa statistics were used to assess the extents of agreement in terms of the number of involved segments (NIS) in disc herniation and epicenter measurements collected using MDCT and MRI. Results The interobserver agreement rates upon evaluation of disc morphology by the three radiologists were in fair to moderate agreement (k = 0.39-0.53 for MDCT images; k = 0.45-0.56 for MRIs). When the disc morphology was categorized into two and four grades, the inter-modality agreement rates were moderate (k-value, 0.59) and substantial (k-value, 0.66), respectively. The inter-modality agreements for evaluations of the NIS (k-value, 0.78) and the epicenter (k-value, 0.79) were substantial. Also, the interobserver agreements for the NIS (CT; k-value, 0.85 and MRI; k-value, 0.88) and epicenter (CT; k-value, 0.74 and MRI; k-value, 0.70) evaluations by two readers were substantial. MDCT tended to underestimate the extent of herniated disc lesions compared with MRI. Conclusion Multidetector-row computed tomography and MRI showed a moderate-to-substantial degree of inter-modality agreement for the assessment of herniated cervical discs. MDCT images have a tendency to underestimate the anterior/posterior extent of the herniated disc compared with MRI. PMID:26175589

Characteristics of Dry Chin-Tuck Swallowing Vibrations and Sounds

PubMed Central

Dudik, Joshua M; Jestrović, Iva; Luan, Bo; Coyle, James L.; Sejdić, Ervin

2015-01-01

Objective The effects of the chin-tuck maneuver, a technique commonly employed to compensate for dysphagia, on cervical auscultation are not fully understood. Characterizing a technique that is known to affect swallowing function is an important step on the way to developing a new instrumentation-based swallowing screening tool. Methods In this study, we recorded data from 55 adult participants who each completed five saliva swallows in a chin-tuck position. The resulting data was processed using previously designed filtering and segmentation algorithms. We then calculated 9 time, frequency, and time-frequency domain features for each independent signal. Results We found that multiple frequency and time domain features varied significantly between male and female subjects as well as between swallowing sounds and vibrations. However, our analysis showed that participant age did not play a significant role on the values of the extracted features. Finally, we found that various frequency features corresponding to swallowing vibrations did demonstrate statistically significant variation between the neutral and chin-tuck positions but sounds showed no changes between these two positions. Conclusion The chin-tuck maneuver affects many facets of swallowing vibrations and sounds and its effects can be monitored via cervical auscultation. Significance These results suggest that a subject’s swallowing technique does need to be accounted for when monitoring their performance with cervical auscultation based instrumentation. PMID:25974926

Development of a computerized intervertebral motion analysis of the cervical spine for clinical application.

PubMed

Piché, Mathieu; Benoît, Pierre; Lambert, Julie; Barrette, Virginie; Grondin, Emmanuelle; Martel, Julie; Paré, Amélie; Cardin, André

2007-01-01

The objective of this study was to develop a measurement method that could be implemented in chiropractic for the evaluation of angular and translational intervertebral motion of the cervical spine. Flexion-extension radiographs were digitized with a scanner at a ratio of 1:1 and imported into a software, allowing segmental motion measurements. The measurements were obtained by selecting the most anteroinferior point and the most posteroinferior point of a vertebral body (anterior and posterior arch, respectively, for C1), with the origin of the reference frame set at the most posteroinferior point of the vertebral body below. The same procedure was performed for both the flexion and extension radiographs, and the coordinates of the 2 points were used to calculate the angular movement and the translation between the 2 vertebrae. This method provides a measure of intervertebral angular and translational movement. It uses a different reference frame for each joint instead of the same reference frame for all joints and thus provides a measure of motion in the plane of each articulation. The calculated values obtained are comparable to other studies on intervertebral motion and support further development to validate the method. The present study proposes a computerized procedure to evaluate intervertebral motion of the cervical spine. This procedure needs to be validated with a reliability study but could provide a valuable tool for doctors of chiropractic and further spinal research.

Inter-operator Reliability of Magnetic Resonance Image-Based Computational Fluid Dynamics Prediction of Cerebrospinal Fluid Motion in the Cervical Spine.

PubMed

Martin, Bryn A; Yiallourou, Theresia I; Pahlavian, Soroush Heidari; Thyagaraj, Suraj; Bunck, Alexander C; Loth, Francis; Sheffer, Daniel B; Kröger, Jan Robert; Stergiopulos, Nikolaos

2016-05-01

For the first time, inter-operator dependence of MRI based computational fluid dynamics (CFD) modeling of cerebrospinal fluid (CSF) in the cervical spinal subarachnoid space (SSS) is evaluated. In vivo MRI flow measurements and anatomy MRI images were obtained at the cervico-medullary junction of a healthy subject and a Chiari I malformation patient. 3D anatomies of the SSS were reconstructed by manual segmentation by four independent operators for both cases. CFD results were compared at nine axial locations along the SSS in terms of hydrodynamic and geometric parameters. Intraclass correlation (ICC) assessed the inter-operator agreement for each parameter over the axial locations and coefficient of variance (CV) compared the percentage of variance for each parameter between the operators. Greater operator dependence was found for the patient (0.19 < ICC < 0.99) near the craniovertebral junction compared to the healthy subject (ICC > 0.78). For the healthy subject, hydraulic diameter and Womersley number had the least variance (CV = ~2%). For the patient, peak diastolic velocity and Reynolds number had the smallest variance (CV = ~3%). These results show a high degree of inter-operator reliability for MRI-based CFD simulations of CSF flow in the cervical spine for healthy subjects and a lower degree of reliability for patients with Type I Chiari malformation.

Inter-Operator Dependence of Magnetic Resonance Image-Based Computational Fluid Dynamics Prediction of Cerebrospinal Fluid Motion in the Cervical Spine

PubMed Central

Martin, Bryn A.; Yiallourou, Theresia I.; Pahlavian, Soroush Heidari; Thyagaraj, Suraj; Bunck, Alexander C.; Loth, Francis; Sheffer, Daniel B.; Kröger, Jan Robert; Stergiopulos, Nikolaos

2015-01-01

For the first time, inter-operator dependence of MRI based computational fluid dynamics (CFD) modeling of cerebrospinal fluid (CSF) in the cervical spinal subarachnoid space (SSS) is evaluated. In vivo MRI flow measurements and anatomy MRI images were obtained at the cervico-medullary junction of a healthy subject and a Chiari I malformation patient. 3D anatomies of the SSS were reconstructed by manual segmentation by four independent operators for both cases. CFD results were compared at nine axial locations along the SSS in terms of hydrodynamic and geometric parameters. Intraclass correlation (ICC) assessed the inter-operator agreement for each parameter over the axial locations and coefficient of variance (CV) compared the percentage of variance for each parameter between the operators. Greater operator dependence was found for the patient (0.19 0.78). For the healthy subject, hydraulic diameter and Womersley number had the least variance (CV= ~2%). For the patient, peak diastolic velocity and Reynolds number had the smallest variance (CV= ~3%). These results show a high degree of inter-operator reliability for MRI-based CFD simulations of CSF flow in the cervical spine for healthy subjects and a lower degree of reliability for patients with Type I Chiari malformation. PMID:26446009

Short-scan-time multi-slice diffusion MRI of the mouse cervical spinal cord using echo planar imaging.

PubMed

Callot, Virginie; Duhamel, Guillaume; Cozzone, Patrick J; Kober, Frank

2008-10-01

Mouse spinal cord (SC) diffusion-weighted imaging (DWI) provides important information on tissue morphology and structural changes that may occur during pathologies such as multiple sclerosis or SC injury. The acquisition scheme of the commonly used DWI techniques is based on conventional spin-echo encoding, which is time-consuming. The purpose of this work was to investigate whether the use of echo planar imaging (EPI) would provide good-quality diffusion MR images of mouse SC, as well as accurate measurements of diffusion-derived metrics, and thus enable diffusion tensor imaging (DTI) and highly resolved DWI within reasonable scan times. A four-shot diffusion-weighted spin-echo EPI (SE-EPI) sequence was evaluated at 11.75 T on a group of healthy mice (n = 10). SE-EPI-derived apparent diffusion coefficients of gray and white matter were compared with those obtained using a conventional spin-echo sequence (c-SE) to validate the accuracy of the method. To take advantage of the reduction in acquisition time offered by the EPI sequence, multi-slice DTI acquisitions were performed covering the cervical segments (six slices, six diffusion-encoding directions, three b values) within 30 min (vs 2 h for c-SE). From these measurements, fractional anisotropy and mean diffusivities were calculated, and fiber tracking along the C1 to C6 cervical segments was performed. In addition, high-resolution images (74 x 94 microm(2)) were acquired within 5 min per direction. Clear delineation of gray and white matter and identical apparent diffusion coefficient values were obtained, with a threefold reduction in acquisition time compared with c-SE. While overcoming the difficulties associated with high spatially and temporally resolved DTI measurements, the present SE-EPI approach permitted identification of reliable quantitative parameters with a reproducibility compatible with the detection of pathologies. The SE-EPI method may be particularly valuable when multiple sets of images from the SC are needed, in cases of rapidly evolving conditions, to decrease the duration of anesthesia or to improve MR exploration by including additional MR measurements. Copyright (c) 2008 John Wiley & Sons, Ltd.

Geophysical and petrological modeling of the lower crust and uppermost mantle in the Variscan and Proterozoic surroundings of the Trans-European Suture Zone in Central Europe

NASA Astrophysics Data System (ADS)

Puziewicz, Jacek; Polkowski, Marcin; Grad, Marek

2017-04-01

High-quality seismic data on the lower crust and uppermost lithospheric mantle in the Central European part of the Trans European Suture Zone, together with thermal and gravimetric data, enables the quantitative modeling of the rocks occurring in those parts of the lithosphere, including their mineral compositions and the chemical composition of individual minerals. The P3 seismic profile is located at the SW margin of the East European Craton. The lower crust is dominated by gabbronoritic intrusions (plagioclase An45Ab55, clinopyroxene Di80Hed20, orthopyroxene En74Fs26), and the uppermost mantle is harzburgitic (olivine and orthopyroxene Mg# 0.91). The lower crust and upper mantle of the P1 seismic profile belong to the Trans European Suture Zone, albeit the upper crust is of Variscan affinity. The P1 lower crust has gabbronoritic composition which is layered from plagioclase-rich compositions on the top to the orthopyroxene-rich ones at the bottom (plagioclase An45Ab55, clinopyroxene Di80Hed20, orthopyroxene En85Fs15), and is lithologically different Proterozoic and Variscan surroundings. The 100 × 200 km eclogite slice (garnet Alm48Gr25Py27, clinopyroxene Di51Hed10Jd39), with a thickness of 5-10 km, occurs in the uppermost mantle sampled by the P1 profile. The Niedźwiedź Massif is located at the NE margin of the Bohemian Massif, which shows an exposed Variscan basement. The lower crust beneath the Niedźwiedź Massif consists of gabbroic rock of variable proportions of plagioclase (An45Ab55) and clinopyroxene (Di80Hed20), whereas the uppermost mantle is supposedly spinel harzburgite (olivine, ortho- and clinopyroxene Mg# 0.90). Our models show that the lowermost crust and uppermost mantle of the East European Craton do not continue to the SW into the Trans European Suture Zone in its Central European section in Poland.

Properties of vestibular neurones projecting to neck segments of the cat spinal cord*

PubMed Central

Rapoport, S.; Susswein, A.; Uchino, Y.; Wilson, V. J.

1977-01-01

1. Vestibular neurones projecting to the upper cervical grey matter (vestibulocollic neurones) were identified by localized microstimulation in the C3 segment of the cat spinal cord. 2. The neurones were found in the lateral (Deiters'), medial and descending nuclei bilaterally and projected to the spinal cord in the lateral and medial vestibulospinal tracts (LVST and MVST). Ipsilateral axons of Deiters' neurones were mostly in the LVST, axons of medial and descending neurones in the MVST; a few Deiters' neurones had axons in the MVST; some descending neurones had axons in the LVST. Most axons of contralateral neurones were in the MVST. 3. The axons of 62% of ipsilateral vestibulocollic Deiters' neurones not only gave off a collateral to C3, but also extended as far as the cervical enlargement (`branching'); some of these neurones projected as far as the upper thoracic cord, almost none to the lumbar cord. Ipsilateral descending nucleus neurones branch in the same fashion, but there is no branching in the relatively small medial nucleus population. 4. A large majority of vestibulocollic neurones receive monosynaptic excitation from the ipsilateral labyrinth and a number are inhibited by stimulation of the contralateral labyrinth (commissural inhibition). It is possible that commissural inhibition acts on a broad population of vestibular neurones involved in the control of eye, head and trunk movement. 5. Vestibulocollic neurones do not make up a homogeneous population acting only on the neck. Instead it is likely that subpopulations, for example branching and non-branching neurones, have different functions. PMID:874918

Short-segment transverse myelitis lesions in a cohort of Latin American patients with neuromyelitis optica spectrum disorders.

PubMed

Carnero Contentti, Edgar; Daccach Marques, Vanessa; Soto de Castillo, Ibis; Tkachuk, Verónica; Antunes Barreira, Amilton; Armas, Elizabeth; Chiganer, Edson; de Aquino Cruz, Camila; Di Pace, José Luis; Hryb, Javier Pablo; Lavigne Moreira, Carolina; Lessa, Carmen; Molina, Omaira; Perassolo, Mónica; Soto, Arnoldo; Caride, Alejandro

2018-05-22

Multicenter retrospective study. The aim was to determine the frequency and magnetic resonance imaging (MRI) features of short-segment transverse myelitis (STM) in patients with neuromyelitis optica spectrum disorders (NMOSD) during a myelitis attack. Latin American diagnostic centres (Neuroimmunology Unit). A multicenter study from Argentina, Brazil and Venezuela was performed. Seventy-six patients with NMOSD were included. We analyzed 346 attacks and reviewed spinal cord MRIs performed within 30 days from spinal attack onset. Sagittal and axial characteristics on cervical and thoracic MRI (1.5 tesla) were observed. Demographics, clinical, serological, and disability data were collected. Among the 76 patients with NMOSD, isolated STM was observed in 8% (n = 6), multisegmental lesions (longitudinally extensive transverse myelitis (LETM) + STM) in 28% (n = 21; 13 had at least one STM), LETM in 42% (n = 32), and normal spinal MRI in 22% (n = 17). However, isolated STM was increased by 10% in patients with NMOSD with spinal lesions (6 out of 59) with mean attacks of 2.5 (±0.83) and last follow-up expanded disability status scale (EDSS) of 3.1 (±2.63). Positive aquaporin 4 antibodies (AQP4-ab) were found in 50%. Upper-cervical lesion was most frequently observed (5 out of 6). Myelitis was preceded by ON in all isolated patients with STM. Only one had a positive gadolinium lesion and none of these had asymptomatic spinal cord lesion. Isolated STM does not exclude NMOSD diagnosis. Therefore, APQ4-ab testing could be useful during a myelitis attack with STM.

Population Coding of Forelimb Joint Kinematics by Peripheral Afferents in Monkeys

PubMed Central

Umeda, Tatsuya; Seki, Kazuhiko; Sato, Masa-aki; Nishimura, Yukio; Kawato, Mitsuo; Isa, Tadashi

2012-01-01

Various peripheral receptors provide information concerning position and movement to the central nervous system to achieve complex and dexterous movements of forelimbs in primates. The response properties of single afferent receptors to movements at a single joint have been examined in detail, but the population coding of peripheral afferents remains poorly defined. In this study, we obtained multichannel recordings from dorsal root ganglion (DRG) neurons in cervical segments of monkeys. We applied the sparse linear regression (SLiR) algorithm to the recordings, which selects useful input signals to reconstruct movement kinematics. Multichannel recordings of peripheral afferents were performed by inserting multi-electrode arrays into the DRGs of lower cervical segments in two anesthetized monkeys. A total of 112 and 92 units were responsive to the passive joint movements or the skin stimulation with a painting brush in Monkey 1 and Monkey 2, respectively. Using the SLiR algorithm, we reconstructed the temporal changes of joint angle, angular velocity, and acceleration at the elbow, wrist, and finger joints from temporal firing patterns of the DRG neurons. By automatically selecting a subset of recorded units, the SLiR achieved superior generalization performance compared with a regularized linear regression algorithm. The SLiR selected not only putative muscle units that were responsive to only the passive movements, but also a number of putative cutaneous units responsive to the skin stimulation. These results suggested that an ensemble of peripheral primary afferents that contains both putative muscle and cutaneous units encode forelimb joint kinematics of non-human primates. PMID:23112841

Bradykinesia induced by frequency-specific pallidal stimulation in patients with cervical and segmental dystonia.

PubMed

Huebl, Julius; Brücke, Christof; Schneider, Gerd-Helge; Blahak, Christian; Krauss, Joachim K; Kühn, Andrea A

2015-07-01

Pallidal deep brain stimulation (DBS) is an effective treatment for patients with primary dystonia leading to a substantial reduction of symptom severity. However, stimulation induced side effects such as bradykinesia have also been reported recently. The influence of stimulation parameters on such side effects have not yet been systemically assessed in these patients. Here we tested the effect of stimulation frequency and duration of stimulation period on hand motor function in 22 patients with primary cervical and segmental dystonia using an unimanual tapping task. Patients performed the task at 4 different stimulation frequencies (0 Hz = OFF stimulation, 20, 50 and ≥130 Hz = high frequency stimulation) after either an SHORT (5 min, N = 16) or a LONG (60 min, N = 6) stimulation period (i.e. changing of DBS-frequency). The change of overall mobility under HFS compared to the preoperative state was assessed with a 5-point Likert-scale. Tapping performance was analysed using a repeated measures ANOVA with the main factor 'FREQUENCY'. Tapping performance at HFS and changes in general mobility were correlated using Spearman's Rho. We found a frequency specific modulation of hand motor function: HFS led to deterioration and 20 Hz stimulation to improvement of tapping rate. The effects were predominant in the 'LONG' group suggesting a significant contribution of stimulation duration. This is important to consider during DBS-programming and evaluation of potential side effects. Furthermore, the impairment in hand motor function under HFS was mirrored by the patients' observation of a deterioration of general mobility. Copyright © 2015 Elsevier Ltd. All rights reserved.

Seismic anisotropy and mantle creep in young orogens

USGS Publications Warehouse

Meissner, R.; Mooney, W.D.; Artemieva, I.

2002-01-01

Seismic anisotropy provides evidence for the physical state and tectonic evolution of the lithosphere. We discuss the origin of anisotropy at various depths, and relate it to tectonic stress, geotherms and rheology. The anisotropy of the uppermost mantle is controlled by the orthorhombic mineral olivine, and may result from ductile deformation, dynamic recrystallization or annealing. Anisotropy beneath young orogens has been measured for the seismic phase Pn that propagates in the uppermost mantle. This anisotropy is interpreted as being caused by deformation during the most recent thermotectonic event, and thus provides information on the process of mountain building. Whereas tectonic stress and many structural features in the upper crust are usually orientated perpendicular to the structural axis of mountain belts, Pn anisotropy is aligned parallel to the structural axis. We interpret this to indicate mountain-parallel ductile (i.e. creeping) deformation in the uppermost mantle that is a consequence of mountain-perpendicular compressive stresses. The preferred orientation of the fast axes of some anisotropic minerals, such as olivine, is known to be in the creep direction, a consequence of the anisotropy of strength and viscosity of orientated minerals. In order to explain the anisotropy of the mantle beneath young orogens we extend the concept of crustal 'escape' (or 'extrusion') tectonics to the uppermost mantle. We present rheological model calculations to support this hypothesis. Mountain-perpendicular horizontal stress (determined in the upper crust) and mountain-parallel seismic anisotropy (in the uppermost mantle) require a zone of ductile decoupling in the middle or lower crust of young mountain belts. Examples for stress and mountain-parallel Pn anisotropy are given for Tibet, the Alpine chains, and young mountain ranges in the Americas. Finally, we suggest a simple model for initiating mountain parallel creep.

Cervical spine motion in manual versus Jackson table turning methods in a cadaveric global instability model.

PubMed

DiPaola, Matthew J; DiPaola, Christian P; Conrad, Bryan P; Horodyski, MaryBeth; Del Rossi, Gianluca; Sawers, Andrew; Bloch, David; Rechtine, Glenn R

2008-06-01

A study of spine biomechanics in a cadaver model. To quantify motion in multiple axes created by transfer methods from stretcher to operating table in the prone position in a cervical global instability model. Patients with an unstable cervical spine remain at high risk for further secondary injury until their spine is adequately surgically stabilized. Previous studies have revealed that collars have significant, but limited benefit in preventing cervical motion when manually transferring patients. The literature proposes multiple methods of patient transfer, although no one method has been universally adopted. To date, no study has effectively evaluated the relationship between spine motion and various patient transfer methods to an operating room table for prone positioning. A global instability was surgically created at C5-6 in 4 fresh cadavers with no history of spine pathology. All cadavers were tested both with and without a rigid cervical collar in the intact and unstable state. Three headrest permutations were evaluated Mayfield (SM USA Inc), Prone View (Dupaco, Oceanside, CA), and Foam Pillow (OSI, Union City, CA). A trained group of medical staff performed each of 2 transfer methods: the "manual" and the "Jackson table" transfer. The manual technique entailed performing a standard rotation of the supine patient on a stretcher to the prone position on the operating room table with in-line manual cervical stabilization. The "Jackson" technique involved sliding the supine patient to the Jackson table (OSI, Union City, CA) with manual in-line cervical stabilization, securing them to the table, then initiating the table's lock and turn mechanism and rotating them into a prone position. An electromagnetic tracking device captured angular motion between the C5 and C6 vertebral segments. Repeated measures statistical analysis was performed to evaluate the following conditions: collar use (2 levels), headrest (3 levels), and turning technique (2 levels). For all measures, there was significantly more cervical spine motion during manual prone positioning compared with using the Jackson table. The use of a collar provided a slight reduction in motion in all the planes of movement; however, this was only significantly different from the no collar condition in axial rotation. Differences in gross motion between the headrest type were observed in lateral bending (Foam Pillow

[Hyperextension trauma in patients with cervical spondylosis].

PubMed

Srámek, J; Stulík, J; Sebesta, P; Vyskocil, T; Kryl, J; Nesnídal, P; Barna, M

2009-04-01

PURPOSE OF THE STUDY To evaluate retrospectively a group of patients with hyperextension injury to the cervical spine who were treated at the Department of Spinal Surgery of the University Hospital in Motol, Prague, between 2003 and 2006. MATERIAL The group comprised 22 patients, 17 men (77 %) and five women (23 %) in the age range of 35 to 81 years, with an average of 59.5 years. All patients had, in association with the injury, neurological deficit of varying degree. METHODS All patients underwent X-ray and magnetic resonance imaging examination and received methylprednisolone according to the National Acute Spinal Cord Injury Study (NASCIS) 2 trial. Eleven patients had urgent surgery within 24 hours of injury; eight patients were operated on within an interval of 3 days to 2 months because of the seriousness of their state and multiple morbidity; and three patients were treated conservatively. Neurological deficit in terms of upper- and lower-limb mobility was evaluated by the American Spinal Injury Association (ASIA) motor score. The values obtained for the urgently operated patients and for those operated on after a time interval were compared by Wilcoxons two-sample test. The other aspects evaluated included trauma aetiology, level of spinal cord injury, manner of treatment, and intra-operative and post-operative complications. RESULTS The most frequent cause of injury was a low-height fall (13 patients; 59 %); car accidents ranked second (9 patients; 41 %). In five patients (22.7 %) ebriety was found. Eighteen patients had no skeletal injury (81.8 %). Four patients (18.2 %). Four patients (18.2 %) suffered fractures of articular or spinous processes, but the anterior column skeleton was intact in all. The segment most frequently affected by myopathy was C3-C4, then C4-C5 and C5-C6. Decompression was carried out to the extent of myopathy; and in the adjacent segments only if significant stenosis was present. In both subgroups of surgically treated patients (urgent and delayed management), comparisons of the ASIA scores at the time of injury and at one-year follow-up showed no significat improvement in post-operative mobility, as evaluated by Wilcoxons two-sample test at a level of significance a = 5 %. No intra-operative or post-operative complications, except for early death, were recorded. In all patients the wound healed by first intention and no loosening of instrumentation was foud on follow-ups at the out-patient departments. DISCUSSION Although the greatest narrowing of the spinal canal due to spondylosis occurs at the C5-C6 segment, the C4-C5 segment sustained most injuries. Although some relevant papers report no significant difference in improved neurological deficit between patients treated surgically and those undergoing conservative therapy, we prefer surgical management, in most of the cases from the anterior approach, which allows us to remove dorsal osteophytes and perform careful decompression to prevent damage to nerve structures and to preserve those which are still intact. There was no significant difference in the outcome between urgent and delayed trauma management, which is unusual amongst other injuries associated with neurological lesions and this indicates that the timing of surgery must be strictly individual and should be carried out at a time when operative benefit outweighs operative burden. The surgical treatment used should, in the first place, lead to early recuperation and rehabilitation. CONCLUSIONS Hyperextension injuries of the cervical spine are usually associated with serious neurological deficit. A correct algorithm of examination will result in good treatment outcomes. However, these injuries require a therapy that is long-lasting and difficult, with a need for cooperation of anaesthesiologists, spinal surgeons, physical therapists and, last but not least, psychologists. Key words: cervical spine, hyperextension injury, spondylosis, myelopathy.

Comparison of different ligature materials used for T-tube esophageal exclusion.

PubMed

Lee, Y C; Luh, S P; Tsai, C C; Hsu, H C; Chu, S H

1992-03-01

Four different ligature materials--plain catgut, chromic catgut, dexon and silk--were used for ligature of the distal arm during T-tube exclusion of the cervical esophagus in 12 dogs. Ligature by plain catgut was maintained for only a short period, but the duration of esophageal occlusion with the other three ligature materials was around 10 days. Ligated esophageal segments were examined grossly and histologically two months after the procedure. The diameter of the esophageal lumen in the ligated segments had become smaller compared with the neighboring normal esophageal lumen. The most prominent histologic changes were atrophy and fibrosis of the muscle coat, vessel congestion and inflammatory cell infiltration in the ligated segments. These tissue reactions were more severe in the chromic catgut and silk ligatures. Among the 11 evaluable dogs, four had symptoms of dysphagia after removal of the T-tube. All four dogs had a sinus discharge and granuloma formation at the T-tube esophagostoma. The diameter of the esophageal lumen was more constricted in dogs with dysphagia. Among the four ligature materials, dexon had the advantages of a long duration of occlusion, less tissue fibrosis and little sequel of esophageal stenosis, making it the most suitable for ligature during esophageal exclusion.

A clinico-epidemiological study of herpes zoster.

PubMed

Aggarwal, S K; Radhakrishnan, S

2016-04-01

Herpes zoster is a common viral infection of skin caused by reactivation of varicella zoster virus infection from the spinal ganglia. The clinico-epidemiological patterns of this disease in an Indian setting required to be studied. A cross sectional study was conducted on all consecutive cases of herpes zoster reporting to the Dermatology Outpatient Department at a Tertiary Care Hospital in Bangalore during a period of one year from 01 Jun 2013 to 31 May 2014. Detailed history, examination, HIV screening and Tzanck smear were carried out in all cases. 84 cases of herpes zoster were seen with a mean age of 30 years. Majority (39%) of cases were seen in the 21-30 year age group. Thoracic segments were involved in 65.4%, cervical in 11.9%, cranial in 11.5%, lumbar in 8.3% and sacral segments in 3.5%. 63% of cases had zoster associated pain. One case had motor involvement.3.57% of the patients were HIV positive. This study shows a lower age incidence of herpes zoster HIV positivity and zoster associated pain as compared to other studies. The pattern of segmental involvement in herpes zoster seen in this study was similar to other studies.

A late neurological complication following posterior correction surgery of severe cervical kyphosis.

PubMed

Hojo, Yoshihiro; Ito, Manabu; Abumi, Kuniyoshi; Kotani, Yoshihisa; Sudo, Hideki; Takahata, Masahiko; Minami, Akio

2011-06-01

Though a possible cause of late neurological deficits after posterior cervical reconstruction surgery was reported to be an iatrogenic foraminal stenosis caused not by implant malposition but probably by posterior shift of the lateral mass induced by tightening screws and plates, its clinical features and pathomechanisms remain unclear. The aim of this retrospective clinical review was to investigate the clinical features of these neurological complications and to analyze the pathomechanisms by reviewing pre- and post-operative imaging studies. Among 227 patients who underwent cervical stabilization using cervical pedicle screws (CPSs), six patients who underwent correction of cervical kyphosis showed postoperative late neurological complications without any malposition of CPS (ND group). The clinical courses of the patients with deficits were reviewed from the medical records. Radiographic assessment of the sagittal alignment was conducted using lateral radiographs. The diameter of the neural foramen was measured on preoperative CT images. These results were compared with the other 14 patients who underwent correction of cervical kyphosis without late postoperative neurological complications (non-ND group). The six patients in the ND group showed no deficits in the immediate postoperative periods, but unilateral muscle weakness of the deltoid and biceps brachii occurred at 2.8 days postoperatively on average. Preoperative sagittal alignment of fusion area showed significant kyphosis in the ND group. The average of kyphosis correction in the ND was 17.6° per fused segment (range 9.7°-35.0°), and 4.5° (range 1.3°-10.0°) in the non-ND group. A statistically significant difference was observed in the degree of preoperative kyphosis and the correction angles at C4-5 between the two groups. The diameter of the C4-5 foramen on the side of deficits was significantly smaller than that of the opposite side in the ND group. Late postoperative neurological complications after correction of cervical kyphosis were highly associated with a large amount of kyphosis correction, which may lead foraminal stenosis and enhance posterior drift of the spinal cord. These factors may lead to both compression and traction of the nerves, which eventually cause late neurological deficits. To avoid such complications, excessive kyphosis correction should not be performed during posterior surgery to avoid significant posterior shift of the spinal cord and prophylactic foraminotomies are recommended if narrow neuroforamina were evident on preoperative CT images. Regardless of revision decompression or observation, the majority of this late neurological complication showed complete recovery over time.

[Mathematical simulation of biomechanical background of osteophyte formation in cervical vertebra].

PubMed

Barsa, P; Novák, J; Souček, T; Maršík, F; Suchomel, P

2011-01-01

The aim of this study was to simulate different types of cervical vertebra loading and to find out whether mechanical stress would concentrate in regions known in clinical practice as predilection sites for osteophyte formation. The objective was to develop a theoretical model that would elucidate clinical observations concerning the predilection site of bone remodelling in view of the physiological changes inside the cervical vertebral body. A real 3D-geometry of the fourth cervical vertebra had been made by the commercially available system ATOS II. This is a high-resolution measuring system using principles of optical triangulation. This flexible optical measuring machine projects fringe patterns on the surface of a selected object and the pattern is observed with two cameras. 3D coordinates for each camera pixel were calculated with high precision and a polygon mesh of the object's surface was further generated. In the next step an ANSYS programme was used to calculate strains and stresses in each finite element of the virtual vertebra. The applied forces used in the experiment corresponded in both magnitude and direction to physiological stress. Mechanical loading in neutral position was characterized by a distribution of 80% mechanical stress to the vertebral body and 10% to each of the zygoapophyseal joints. Hyperlordotic loading was simulated by 60% force transfer to the vertebral body end-plate and 20% to each of the small joint while kyphotic loading involved a 90% load on the vertebral body endplate and 5% on each facet. Mechanical stress distribution calculated in a neutral position of the model correlated well with bone mineral distribution of a healthy vertebra, and verified the model itself. The virtual mechanical loading of a vertebra in kyphotic position concentrated deformation stress into the uncinate processes and the dorsal apophyseal rim of the vertebral body. The simulation of mechanical loading in hyperlordosis, on the other hand, shifted the region of maximum deformation into the articulation process of the Z-joint. All locations are known as areas of osteophyte formation in degenerated cervical vertebrae. The theoretical model developed during this study corresponded well with human spine behaviour in terms of predilection sites for osteodegenerative changes, as observed in clinical practice. A mathematical simulation of mechanical stress distribution in pre-operative planning may lead to the optimisation of post-operative anatomical relationship between adjacent vertebrae. Such improvement in our surgical practice may further reduce the incidence of degenerative changes in adjacent motion segments of the cervical spine and possibly also lead to better subjective and clinical results after cervical spine reconstruction.

Cost-utility analysis modeling at 2-year follow-up for cervical disc arthroplasty versus anterior cervical discectomy and fusion: A single-center contribution to the randomized controlled trial

PubMed Central

Warren, Daniel; Andres, Tate; Hoelscher, Christian; Ricart-Hoffiz, Pedro; Bendo, John; Goldstein, Jeffrey

2013-01-01

Background Patients with cervical disc herniations resulting in radiculopathy or myelopathy from single level disease have traditionally been treated with Anterior Cervical Discectomy and Fusion (ACDF), yet Cervical Disc Arthroplasty (CDA) is a new alternative. Expert suggestion of reduced adjacent segment degeneration is a promising future result of CDA. A cost-utility analysis of these procedures with long-term follow-up has not been previously reported. Methods We reviewed single institution prospective data from a randomized trial comparing single-level ACDF and CDA in cervical disc disease. Both Medicare reimbursement schedules and actual hospital cost data for peri-operative care were separately reviewed and analyzed to estimate the cost of treatment of each patient. QALYs were calculated at 1 and 2 years based on NDI and SF-36 outcome scores, and incremental cost effectiveness ratio (ICER) analysis was performed to determine relative cost-effectiveness. Results Patients of both groups showed improvement in NDI and SF-36 outcome scores. Medicare reimbursement rates to the hospital were $11,747 and $10,015 for ACDF and CDA, respectively; these figures rose to $16,162 and $13,171 when including physician and anesthesiologist reimbursement. The estimated actual cost to the hospital of ACDF averaged $16,108, while CDA averaged $16,004 (p = 0.97); when including estimated physicians fees, total hospital costs came to $19,811 and $18,440, respectively. The cost/QALY analyses therefore varied widely with these discrepancies in cost values. The ICERs of ACDF vs CDA with Medicare reimbursements were $18,593 (NDI) and $19,940 (SF-36), while ICERs based on actual total hospital cost were $13,710 (NDI) and $9,140 (SF-36). Conclusions We confirm the efficacy of ACDF and CDA in the treatment of cervical disc disease, as our results suggest similar clinical outcomes at one and two year follow-up. The ICER suggests that the non-significant added benefit via ACDF comes at a reasonable cost, whether we use actual hospital costs or Medicare reimbursement values, though the actual ICER values vary widely depending upon the CUA modality used. Long term follow-up may illustrate a different profile for CDA due to reduced cost and greater long-term utility scores. It is crucial to note that financial modeling plays an important role in how economic treatment dominance is portrayed. PMID:25694905

Analysis of the three United States Food and Drug Administration investigational device exemption cervical arthroplasty trials.

PubMed

Upadhyaya, Cheerag D; Wu, Jau-Ching; Trost, Gregory; Haid, Regis W; Traynelis, Vincent C; Tay, Bobby; Coric, Domagoj; Mummaneni, Praveen V

2012-03-01

There are now 3 randomized, multicenter, US FDA investigational device exemption, industry-sponsored studies comparing arthroplasty with anterior cervical discectomy and fusion (ACDF) for single-level cervical disease with 2 years of follow-up. These 3 studies evaluated the Prestige ST, Bryan, and ProDisc-C artificial discs. The authors analyzed the combined results of these trials. A total of 1213 patients with symptomatic, single-level cervical disc disease were randomized into 2 treatment arms in the 3 randomized trials. Six hundred twenty-one patients received an artificial cervical disc, and 592 patients were treated with ACDF. In the three trials, 94% of the arthroplasty group and 87% of the ACDF group have completed 2 years of follow-up. The authors analyzed the 2-year data from these 3 trials including previously unpublished source data. Statistical analysis was performed with fixed and random effects models. The authors' analysis revealed that segmental sagittal motion was preserved with arthroplasty (preoperatively 7.26° and postoperatively 8.14°) at the 2-year time point. The fusion rate for ACDF at 2 years was 95%. The Neck Disability Index, 36-Item Short Form Health Survey Mental, and Physical Component Summaries, neck pain, and arm pain scores were not statistically different between the groups at the 24-month follow-up. The arthroplasty group demonstrated superior results at 24 months in neurological success (RR 0.595, I(2) = 0%, p = 0.006). The arthroplasty group had a lower rate of secondary surgeries at the 2-year time point (RR 0.44, I(2) = 0%, p = 0.004). At the 2-year time point, the reoperation rate for adjacent-level disease was lower for the arthroplasty group when the authors analyzed the combined data set using a fixed effects model (RR 0.460, I(2) = 2.9%, p = 0.030), but this finding was not significant using a random effects model. Adverse event reporting was too heterogeneous between the 3 trials to combine for analysis. Both anterior cervical discectomy and fusion as well as arthroplasty demonstrate excellent 2-year surgical results for the treatment of 1-level cervical disc disease with radiculopathy. Arthroplasty is associated with a lower rate of secondary surgery and a higher rate of neurological success at 2 years. Arthroplasty may be associated with a lower rate of adjacent-level disease at 2 years, but further follow-up and analysis are needed to confirm this finding.

The accuracy of the lateral vertebral notch-referred pedicle screw insertion technique in subaxial cervical spine: a human cadaver study.

PubMed

Luo, Jiaquan; Wu, Chunyang; Huang, Zhongren; Pan, Zhimin; Li, Zhiyun; Zhong, Junlong; Chen, Yiwei; Han, Zhimin; Cao, Kai

2017-04-01

This is a cadaver specimen study to confirm new pedicle screw (PS) entry point and trajectory for subaxial cervical PS insertion. To assess the accuracy of the lateral vertebral notch-referred PS insertion technique in subaxial cervical spine in cadaver cervical spine. Reported morphometric landmarks used to guide the surgeon in PS insertion show significant variability. In the previous study, we proposed a new technique (as called "notch-referred" technique) primarily based on coronal multiplane reconstruction images (CMRI) and cortical integrity after PS insertion in cadavers. However, the PS position in cadaveric cervical segment was not confirmed radiologically. Therefore, the difference between the pedicle trajectory and the PS trajectory using the notch-referred technique needs to be illuminated. Twelve cadaveric cervical spines were conducted with PS insertion using the lateral vertebral notch-referred technique. The guideline for entry point and trajectory for each vertebra was established based on the morphometric data from our previous study. After 3.5-mm diameter screw insertion, each vertebra was dissected and inspected for pedicle trajectory by CT scan. The pedicle trajectory and PS trajectory were measured and compared in axial plane. The perforation rate was assessed radiologically and was graded from ideal to unacceptable: Grade 0 = screw in pedicle; Grade I = perforation of pedicle wall less than one-fourth of the screw diameter; Grade II = perforation more than one-fourth of the screw diameter but less than one-second; Grade III = perforation more than one-second outside of the screw diameter. In addition, pedicle width between the acceptable and unacceptable screws was compared. A total of 120 pedicle screws were inserted. The perforation rate of pedicle screws was 78.3% in grade 0 (excellent PS position), 10.0% in grade I (good PS position), 8.3% in grade II (fair PS position), and 3.3% in grade III (poor PS position). The overall accepted accuracy of pedicle screws was 96.7% (Grade 0 + Grade I + Grade II), and only 3.3% had critical breach. There was no statistical difference between the pedicle trajectory and PS trajectory (p > 0.05). Compared to the pedicle width (4.4 ± 0.7 mm) in acceptably inserted screw, the unacceptably screw is 3.2 ± 0.3 mm which was statistically different (p < 0.05). The accuracy of the notch-referred PS insertion in cadaveric subaxial cervical spine is satisfactory.

Is cervical disc arthroplasty good for congenital cervical stenosis?

PubMed

Chang, Peng-Yuan; Chang, Hsuan-Kan; Wu, Jau-Ching; Huang, Wen-Cheng; Fay, Li-Yu; Tu, Tsung-Hsi; Wu, Ching-Lan; Cheng, Henrich

2017-05-01

OBJECTIVE Cervical disc arthroplasty (CDA) has been demonstrated to be as safe and effective as anterior cervical discectomy and fusion (ACDF) in the management of 1- and 2-level degenerative disc disease (DDD). However, there has been a lack of data to address the fundamental discrepancy between the two surgeries (CDA vs ACDF), and preservation versus elimination of motion, in the management of cervical myelopathy associated with congenital cervical stenosis (CCS). Although younger patients tend to benefit more from motion preservation, it is uncertain if CCS caused by multilevel DDD can be treated safely with CDA. METHODS Consecutive patients who underwent 3-level anterior cervical discectomy were retrospectively reviewed. Inclusion criteria were age less than 50 years, CCS (Pavlov ratio ≤ 0.82), symptomatic myelopathy correlated with DDD, and stenosis limited to 3 levels of the subaxial cervical (C3-7) spine. Exclusion criteria were ossification of the posterior longitudinal ligament, previous posterior decompression surgery (e.g., laminoplasty or laminectomy), osteoporosis, previous trauma, or other rheumatic diseases that might have caused the cervical myelopathy. All these patients who underwent 3-level discectomy were divided into 2 groups according to the strategies of management: preservation or elimination of motion (the hybrid-CDA group and the ACDF group). The hybrid-CDA group underwent 2-level CDA plus 1-level ACDF, whereas the ACDF group underwent 3-level ACDF. Clinical assessment was measured by the visual analog scales (VAS) for neck and arm pain, Japanese Orthopaedic Association (JOA) scores, and Nurick grades. Radiographic outcomes were measured using dynamic radiographs for evaluation of range of motion (ROM). RESULTS Thirty-seven patients, with a mean (± SD) age of 44.57 ± 5.10 years, were included in the final analysis. There was a male predominance in this series (78.4%, 29 male patients), and the mean follow-up duration was 2.37 ± 1.60 years. There were 20 patients in the hybrid-CDA group, and 17 in the ACDF group. Both groups demonstrated similar clinical improvement at 2 years' follow-up. These patients with 3-level stenosis experienced significant improvement after either type of surgery (hybrid-CDA and ACDF). There were no significant differences between the 2 groups at each of the follow-up visits postoperatively. The preoperative ROM over the operated subaxial levels was similar between both groups (21.9° vs 21.67°; p = 0.94). Postoperatively, the hybrid-CDA group had significantly greater ROM (10.65° vs 2.19°; p < 0.001) than the ACDF group. Complications, adverse events, and reoperations in both groups were similarly low. CONCLUSIONS Hybrid-CDA yielded similar clinical improvement to 3-level ACDF in patients with myelopathy caused by CCS. In this relatively young group of patients, hybrid-CDA demonstrated significantly more ROM than 3-level ACDF without adjacent-segment disease (ASD) at 2 years' follow-up. Therefore, hybrid-CDA appears to be an acceptable option in the management of CCS. The strategy of motion preservation yielded similar improvements of cervical myelopathy to motion elimination (i.e., ACDF) in patients with CCS, while the theoretical benefit of reducing ASD required further validation.

Revisiting the segmental organization of the human spinal cord.

PubMed

Leijnse, J N; D'Herde, K

2016-09-01

In classic anatomic atlases, the spinal cord is standardly represented in its anatomical form with symmetrically emerging anterior and posterior roots, which at the level of the intervertebral foramen combine into the spinal nerves. The parts of the cord delimited by the boundaries of the roots are called segments or myelomeres. Associated with their regular repetitive appearance is the notion that the cord is segmentally organized. This segmental view is reinforced by clinical practice. Spinal cord roots innervate specific body parts. The level of cord trauma is diagnosed by the de-innervation symptoms of these parts. However, systemically, the case for a segmentally organized cord is not so clear. To date, developmental and genetic research points to a regionally rather than a segmentally organized cord. In the present study, to what degree the fila radicularia are segmentally implanted along the cord was investigated. The research hypothesis was that if the fila radicularia were non-segmentally implanted at the cord surface, it would be unlikely that the internal neuron stratum would be segmented. The visual segmented aspect of the myelomeres would then be the consequence of the necessary bundling of axons towards the vertebral foramen as the only exits of the vertebral canal, rather than of an underlying segment organization of the cord itself. To investigate the research hypothesis, the fila radicularia in the cervical-upper thoracic part of five spinal cords were detached from their spinal nerves and dissected in detail. The principal research question was if the fila radicularia are separated from their spinal nerves and dissected from their connective tissues up to the cord, would it be possible to reconstruct the original spinal segments from the morphology and interspaces of the fila? The dissections revealed that the anterior fila radicularia emerge from the cord at regular regionally modulated interspaces without systematic segmental delineations. The posterior fila radicularia are somewhat more segmentally implanted, but the pattern is individually inconsistent. The posterior and anterior roots have notable morphological differences, and hypotheses are presented to help explain these. The macroscopic observations are consistent with a regionally but not a segmentally organized cord. This conclusion was visually summarized in photographs of spinal cords with ipsilateral intact roots and contralateral individually dissected fila radicularia. It was suggested that this dual view of the spinal cord be added to the standard anatomic textbooks to counterbalance the current possibly biased view of a segmented cord. © 2016 Anatomical Society.

Methodology for the systematic reviews on an adjacent segment pathology.

PubMed

Norvell, Daniel C; Dettori, Joseph R; Skelly, Andrea C; Riew, K Daniel; Chapman, Jens R; Anderson, Paul A

2012-10-15

A systematic review. To provide a detailed description of the methods undertaken in the systematic search and analytical summary of adjacent segment pathology (ASP) issues and to describe the process used to develop consensus statements and clinical recommendations regarding factors associated with the prevention and treatment of ASP. We present methods used in conducting the systematic, evidence-based reviews and development of expert panel consensus statements and clinical recommendations on the classification, natural history, risk factors, and treatment of radiographical and clinical ASP. Our intent is that clinicians will combine the information from these reviews with an understanding of their own capacities and experience to better manage patients at risk of ASP and consider future research for the prevention and treatment of ASP. A systematic search and critical review of the English-language literature was undertaken for articles published on the classification, risk, risk factors, and treatment of radiographical and clinical ASP. Articles were screened for relevance using a priori criteria, and relevant articles were critically reviewed. Whether an article was included for review depended on whether the study question was descriptive, one of therapy, or one of prognosis. The strength of evidence for the overall body of literature in each topic area was determined by 2 independent reviewers considering risk of bias, consistency, directness, and precision of results using a modification of the Grades of Recommendation Assessment, Development and Evaluation (GRADE) criteria. Disagreements were resolved by consensus. Findings from articles meeting inclusion criteria were summarized. From these summaries, consensus statements or clinical recommendations were formulated among subject experts through a modified Delphi process using the GRADE approach. A total of 3382 articles were identified and screened on 14 topics relating to the classification, risks, risk factors, and treatment of radiographical and clinical ASP. Of these, 127 met our predetermined inclusion criteria and were used to answer specific clinical questions within each topic. Lack of precision in the terminology related to adjacent segment disease and critical evaluation of definitions used across included articles led to a consensus to use ASP and suggest it as a standard. No validated comprehensive classification system for ASP currently exists. The expert panel developed a consensus definition of radiographical and clinical ASP (RASP and CASP). Some of the highlights from the analyses included the annual, 5- and 10-year risks of developing cervical and lumbar ASP after surgery, several important risk factors associated with the development of cervical and lumbar ASP, and the possibility that some motion sparing procedures may be associated with a lower risk of ASP compared with fusion despite kinematic studies demonstrating similar adjacent segment mobility following these procedures. Other highlights included a high risk of proximal junctional kyphosis (PJK) following long fusions for deformity correction, postsurgical malalignment as a potential risk factor for RASP and the paucity of studies on treatment of cervical and lumbar ASP. Systematic reviews were undertaken to understand the classification, risks, risk factors, and treatment of RASP and CASP and to provide consensus statements and clinical recommendations. This article reports the methods used in the reviews.

Comparison of hybrid constructs with 2-level artificial disc replacement and 2-level anterior cervical discectomy and fusion for surgical reconstruction of the cervical spine: a kinematic study in whole cadavers.

PubMed

Liu, Baoge; Zeng, Zheng; Hoof, Tom Van; Kalala, Jean Pierre; Liu, Zhenyu; Wu, Bingxuan

2015-04-08

Multi-level cervical degeneration of the spine is a common clinical pathology that is often repaired by anterior cervical discectomy and fusion (ACDF). The aim of this study was to investigate the kinematics of the cervical spine after hybrid surgery compared with 2-level ACDF. Five freshly frozen, unembalmed whole human cadavers were used including 3 males and 2 females with a mean age of 51 ± 8 years. After evaluating the intact spine for range of motion (ROM), sagittal alignment and instantaneous center of rotation (ICR), each cadaver underwent 4 consecutive surgeries: 2-level artificial disc replacement (ADR) from C4 to C6 (ADR surgery); 2-level ACDF from C4 to C6 (ACDF surgery); hybrid C4-5 ACDF and C5-6 ADR (ACDF+ADR surgery); and hybrid C4-5 ADR and C5-6 ACDF (ADR+ACDF surgery). The ROM and ICR of adjacent intact segments (C3-4; C6-7), and whole sagittal alignment were revaluated. Two-level ACDF resulted in increased ROM at C3-4 and C6-7 compared with intact spine. ROM was significantly different to intact spine using ACDF surgery at C3-C4 and C6-C7 and ROM was increased with ACDF+ADR surgery at C6-C7 (all P<0.05). No improvement in sagittal alignment was observed with any approach. The localization of the ICR shifted upwards and anteriorly at C3-C4 after reconstruction. ICR changes at C3-C4 were greatest for ADR+ACDF surgery and were significantly different to ACDF surgery (P<0.05), but not between ADR surgery and ACDF+ADR surgery. At C6-C7, the ICR was more posterior and superior than in the intact condition. The greatest change in ICR was observed in ACDF surgery at the C6-C7 level, significantly different from the other groups (P<0.05). For 2-level reconstruction, hybrid surgery and ADR did not alter ROM and minimally changed ICR at the adjacent-level. The type of surgery had a significant impact on the ICR location. This suggests that hybrid surgery may be a viable option for 2-level cervical surgery.

Comparative analysis of clinical outcomes between zero-profile implant and cages with plate fixation in treating multilevel cervical spondilotic myelopathy: A three-year follow-up.

PubMed

Chen, Yu; Chen, Huajiang; Wu, Xiaodong; Wang, Xinwei; Lin, Wenbo; Yuan, Wen

2016-05-01

This study aimed to figure out three-year clinical outcomes and complications of ACDF with Zero-p in treating multilevel cervical spondylotic myelopathy (MCSM) by comparing with plate fixation. Patients with MCSM caused by degenerative disc herniation only were recruited from April 2010 to December 2010. According to the surgical procedures, the patients were divided into two groups at random, the plate group and Zero-P group. The data was collected before surgery and at three-year follow-up. Clinical parameters, including Japanese orthopedic association (JOA) score, neck disabled index (NDI) were evaluated. Cervical segmental lordosis was calculated and fusion in each level was assessed on lateral radiographs. The Bazaz's criterion and the short Swallowing and Quality of Life (SQOL) questionnaires were used to evaluate the dysphagia incidence and severity respectively. The presence of ALOD was observed and recorded on lateral radiographs. A total of 72 patients (46 men and 26 women) were recruited. The mean age at operation was 52.9±7.9years, ranged from 43 to 69 years. There was no significant difference between two groups preoperatively in age, sex, operative levels, JOA, NDI, cervical lordosis, dysphagia incidence, SQOL and ALOD incidence. JOA, NDI and cervical lordosis improved postoperatively and postoperative SQOL got restitution in both groups. However, no difference was detected. There were 7 patients with ALOD in the plate group after surgeries while there was only 1 patient in Zero-P group. The difference of AOLD incidence between them was significant. Of the 7 patients with ALOD in the plate group, 4 patients developed ALOD in cranial level, 2 in caudal level and 1 in both levels. The patient in Zero-P group developed ALOD in caudal level. Based on the three-year follow-up, we could not conclude that Zero-P was superior to plate fixation in clinical outcomes such as neurological results, cervical lordosis, fusion rate and the incidence and severity of dysphagia in treating MCSM. However, it had the advantage of reducing ALOD incidence which tended to happen in ACDF with plate fixation. Copyright © 2016 Elsevier B.V. All rights reserved.

Neuropeptide Y in human spinal cord.

PubMed

Allen, J M; Gibson, S J; Adrian, T E; Polak, J M; Bloom, S R

1984-08-06

The distribution of a newly described peptide, neuropeptide Y (NPY) within the human spinal cord has been determined using radioimmunoassay and immunocytochemistry. Higher concentrations were found in the lumbar (49.9 +/- 6.8 pmol/g) and sacral (47.0 +/- 10.6 pmol/g) regions than in the cervical (27.6 +/- 2.7 pmol/g) and thoracic spinal cord (33.8 +/- 5.3 pmol/g). Immunocytochemistry revealed numerous nerve fibers containing NPY in the spinal cord; these were particularly concentrated in the substantia gelatinosa of the dorsal horn. In the ventral spinal cord NPY-containing nerves were sparse becoming more abundant in lumbosacral segments.

Determination of Isthmocele Using a Foley Catheter During Laparoscopic Repair of Cesarean Scar Defect.

PubMed

Akdemir, Ali; Sahin, Cagdas; Ari, Sabahattin Anil; Ergenoglu, Mete; Ulukus, Murat; Karadadas, Nedim

2018-01-01

To demonstrate a new technique of isthmocele repair via laparoscopic surgery. Case report (Canadian Task Force classification III). The local Ethics Committee waived the requirement for approval. Isthmocele localized at a low uterine segment is a defect of a previous caesarean scar due to poor myometrial healing after surgery [1]. This pouch accumulates menstrual bleeding, which can cause various disturbances and irregularities, including abnormal uterine bleeding, infertility, pelvic pain, and scar pregnancy [2-6]. Given the absence of a clearly defined surgical method in the literature, choosing the proper approach to treating isthmocele can be arduous. Laparoscopy provides a minimally invasive procedure in women with previous caesarean scar defects. A 28-year-old woman, gravida 2 para 2, presented with a complaint of prolonged postmenstrual bleeding for 5 years. She had undergone 2 cesarean deliveries. Transvaginal ultrasonography revealed a hypoechogenic area with menstrual blood in the anterior lower uterine segment. Magnetic resonance imaging showed an isthmocele localized at the anterior left lateral side of the uterus, with an estimated volume of approximately 12 cm 3 . After patient preparation, laparoscopy was performed. To repair the defect, the uterovesical peritoneal fold was incised and the bladder was mobilized from the lower uterine segment. During this surgery, differentiating the isthmocele from the abdomen can be challenging. Here we used a Foley catheter to identify the isthmocele. To do this, after mobilizing the bladder from the lower uterine segment, we inserted a Foley catheter into the uterine cavity through the cervical canal. We then filled the balloon of the catheter at the lower uterine segment under laparoscopic view, which allowed clear identification of the isthmocele pouch. The uterine defect was then incised. The isthmocele cavity was accessed, the margins of the pouch were debrided, and the edges were surgically reapproximated with continuous nonlocking single layer 2-0 polydioxanone sutures. We believed that single-layer suturing could provide for proper healing without necrosis due to suturation. During the procedure, the vesicouterine space was dissected without difficulty. A urine bag was collected with clear urine, and there was no gas leakage; thus, we considered a safety test for the bladder superfluous. Based on concerns about the possible increased risk of adhesions, we did not cover peritoneum over the suture. The patients experienced no associated complications, and she reported complete resolution of prolonged postmenstrual bleeding at a 3-month follow-up. Even though the literature is cloudy in this area, a laparoscopic approach to repairing an isthmocele is a safe and minimally invasive procedure. Our approach described here involves inserting a Foley catheter in the uterine cavity through the cervical canal, then filling the balloon in the lower uterine segment under laparoscopic view to identify the isthmocele. Copyright © 2017 AAGL. Published by Elsevier Inc. All rights reserved.

Spine segmentation from C-arm CT data sets: application to region-of-interest volumes for spinal interventions

NASA Astrophysics Data System (ADS)

Buerger, C.; Lorenz, C.; Babic, D.; Hoppenbrouwers, J.; Homan, R.; Nachabe, R.; Racadio, J. M.; Grass, M.

2017-03-01

Spinal fusion is a common procedure to stabilize the spinal column by fixating parts of the spine. In such procedures, metal screws are inserted through the patients back into a vertebra, and the screws of adjacent vertebrae are connected by metal rods to generate a fixed bridge. In these procedures, 3D image guidance for intervention planning and outcome control is required. Here, for anatomical guidance, an automated approach for vertebra segmentation from C-arm CT images of the spine is introduced and evaluated. As a prerequisite, 3D C-arm CT images are acquired covering the vertebrae of interest. An automatic model-based segmentation approach is applied to delineate the outline of the vertebrae of interest. The segmentation approach is based on 24 partial models of the cervical, thoracic and lumbar vertebrae which aggregate information about (i) the basic shape itself, (ii) trained features for image based adaptation, and (iii) potential shape variations. Since the volume data sets generated by the C-arm system are limited to a certain region of the spine the target vertebra and hence initial model position is assigned interactively. The approach was trained and tested on 21 human cadaver scans. A 3-fold cross validation to ground truth annotations yields overall mean segmentation errors of 0.5 mm for T1 to 1.1 mm for C6. The results are promising and show potential to support the clinician in pedicle screw path and rod planning to allow accurate and reproducible insertions.

Rheumatic diseases of the spine: imaging diagnosis.

PubMed

Narváez, J A; Hernández-Gañán, J; Isern, J; Sánchez-Fernández, J J

2016-04-01

Spinal involvement is common both in the spondyloarthritides and in rheumatoid arthritis, in which the cervical segment is selectively affected. Rheumatoid involvement of the cervical spine has characteristic radiologic manifestations, fundamentally different patterns of atlantoaxial instability. Magnetic resonance imaging (MRI) is the technique of choice for evaluating the possible repercussions of atlantoaxial instability on the spinal cord and/or nerve roots in patients with rheumatoid arthritis as well as for evaluating parameters indicative of active inflammation, such as bone edema and synovitis. Axial involvement is characteristic in the spondyloarthritides and has distinctive manifestations on plain-film X-rays, which reflect destructive and reparative phenomena. The use of MRI has changed the conception of spondyloarthritis because it is able to directly detect the inflammatory changes that form part of the disease, making it possible to establish the diagnosis early in the disease process, when plain-film X-ray findings are normal (non-radiographic axial spondyloarthritis), to assess the prognosis of the disease, and to contribute to treatment planning. Copyright © 2016 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

Petrogenesis of the NE Gondwanan uppermost Ediacaran-Lower Cretaceous siliciclastic sequence of Jordan: Provenance, tectonic, and climatic implications

NASA Astrophysics Data System (ADS)

Amireh, Belal S.

2018-04-01

Detrital framework modes of the NE Gondwanan uppermost Ediacaran-Lower Cretaceous siliciclastic sequence of Jordan are determined employing the routine polarized light microscope. The lower part of this sequence constitutes a segment of the vast lower Paleozoic siliciclastic sheet flanking the northern Gondwana margin that was deposited over a regional unconformity truncating the outskirts of the East African orogen in the aftermath of the Neoproterozoic amalgamation of Gondwana. The research aims to evaluate the factors governing the detrital light mineral composition of this sandstone. The provenance terranes of the Arabian craton controlled by plate tectonics appear to be the primary factor in most of the formations, which could be either directly inferred employing Dickinson's compositional triangles or implied utilizing the petrographic data achieved and the available tectonic and geological data. The Arabian-Nubian Shield constitutes invariably the craton interior or the transitional provenance terrane within the NE Gondwana continental block that consistently supplied sandy detritus through northward-flowing braided rivers to all the lower Paleozoic formations. On the other hand, the Lower Cretaceous Series received siliciclastic debris, through braided-meandering rivers having same northward dispersal direction, additionally from the lower Paleozoic and lower-middle Mesozoic platform strata in the Arabian Craton. The formations making about 50% of the siliciclastic sequence represent a success for Dickinson's plate tectonics-provenance approach in attributing the detrital framework components primarily to the plate tectonic setting of the provenance terranes. However, even under this success, the varying effects of the other secondary sedimentological and paleoclimatological factors are important and could be crucial. The inapplicability of this approach to infer the appropriate provenance terranes of the remaining formations could be ascribed either to the special influence of local intracratonic syn-rift rhyolitic extrusions, where their plate tectonic setting is not represented by the standard plate tectonics-provenance diagrams, or to the rather unusual effect of the Late Ordovician glacial event.

Stabilizing properties of the halo apparatus.

PubMed

Mirza, S K; Moquin, R R; Anderson, P A; Tencer, A F; Steinmann, J; Varnau, D

1997-04-01

A cadaveric cervical spine specimen fixed between a fiberglass torso and a plastic skull was used as a model to determine the effect of halo structural parameters on motion at a lesion simulated at C5-C6. In a second part, nine commercially available halo devices were compared. To define the contributions of the various components of the halo apparatus to reducing motion in an injured cervical spine and to compare the stability offered by a sample of commercially available halo devices. Controversy exists concerning the ability of the halo apparatus to stabilize the injured cervical spine. The halo apparatus has been shown to be the most effective nonsurgical method for stabilizing the fractured spine. Nonetheless, several clinical studies have demonstrated that unacceptably large motions can occur at the injured spinal segment stabilized with a halo apparatus. Each cadaveric cervical spine was mounted onto a fiberglass torso and a rigid plastic skull was attached to the base of the occiput. A posterior ligamentous lesion was created between C5 and C6. The halo ring was fitted to the skull and a vest to the torso. Loads were applied to the skull in flexion, extension, and lateral bending, and relative angulation between C5 and C6 was measured with electroinclinometers. In the first part, the effect of parameters such as vest tightness, vest-thorax friction, vest deformation, and connecting bar rigidity on spinal angulation were measured using one vest. In the second part, the stability offered by each of nine commercially available halo devices was compared. Increasing chest strap tightness and decreasing vest deformation reduced angulation at the spinal lesion. Once connecting bar joints were tightened to 25% of their recommended torque, increased tightening or adding additional bars had no effect on rigidity. Although specific vests permitted significantly greater motion in specific directions, no vest allowed greater angulation consistently in all loading planes. Increasing vest tightness, decreasing the deformability of the vest, and ensuring a good fit can reduce motion in the fractured spine. Most commercially available halo vests provide similar mechanical stability to the injured cervical spine.

Head-Neck Biomechanics in Simulated Rear Impact

PubMed Central

Yoganandan, Narayan; Pintar, Frank A.; Cusick, Joseph F.; Kleinberger, Michael

1998-01-01

The first objective of this study is to present an overview of the human cadaver studies aimed to determine the biomechanics of the head-neck in a simulated rear crash. The need for kinematic studies to better understand the mechanisms of load transfer to the human head-neck complex is emphasized. Based on this need, a methodology is developed to delineate the dynamic kinematics of the human head-neck complex. Intact human cadaver head-neck complexes were subjected to postero-anterior impact using a mini-sled pendulum device. The integrity of the soft tissues including the musculature and skin were maintained. The kinematic data were recorded using high-speed photography coupled with retroreflective targets placed at various regions of the human head-neck complex. The overall and segmental kinematics of the entire head-neck complex, and the localized facet joint motions were determined. During the initial stages of loading, a transient decoupling of the head occurred with respect to the neck exhibiting a lag of the cranium. The upper cervical spine-head undergoes local flexion concomitant with a lag of the head while the lower cervical spinal column is in local extension. This establishes a reverse curvature to the cervical head-neck complex. With continued loading, head motion ensues and approximately at the end of the loading phase, the entire head-neck complex is under the extension mode with a single curvature. In contrast, the lower cervical spine facet joint kinematics show varying compression and sliding. While both the anterior and posterior-most regions of the facet joint slide, the posterior-most region (mean: 2.84 mm) of the joint compresses more than the anterior-most (mean: 2.02 mm) region. These varying kinematics at the ends of the facet joint result in a pinching mechanism. These biomechanical kinematic findings may be correlated to the presence of headaches and neck pain (Lord, Bogduk et al. 1992; Barnsley, Lord et al. 1995), based on the unique human head-neck anatomy at the upper cervical spine region and the associated facet joint characteristics, and clinical studies.

Four lateral mass screw fixation techniques in lower cervical spine following laminectomy: a finite element analysis study of stress distribution.

PubMed

Song, Mingzhi; Zhang, Zhen; Lu, Ming; Zong, Junwei; Dong, Chao; Ma, Kai; Wang, Shouyu

2014-08-09

Lateral mass screw fixation (LSF) techniques have been widely used for reconstructing and stabilizing the cervical spine; however, complications may result depending on the choice of surgeon. There are only a few reports related to LSF applications, even though fracture fixation has become a severe complication. This study establishes the three-dimensional finite element model of the lower cervical spine, and compares the stress distribution of the four LSF techniques (Magerl, Roy-Camille, Anderson, and An), following laminectomy -- to explore the risks of rupture after fixation. CT scans were performed on a healthy adult female volunteer, and Digital imaging and communication in medicine (Dicom) data was obtained. Mimics 10.01, Geomagic Studio 12.0, Solidworks 2012, HyperMesh 10.1 and Abaqus 6.12 software programs were used to establish the intact model of the lower cervical spines (C3-C7), a postoperative model after laminectomy, and a reconstructive model after applying the LSF techniques. A compressive preload of 74 N combined with a pure moment of 1.8 Nm was applied to the intact and reconstructive model, simulating normal flexion, extension, lateral bending, and axial rotation. The stress distribution of the four LSF techniques was compared by analyzing the maximum von Mises stress. The three-dimensional finite element model of the intact C3-C7 vertebrae was successfully established. This model consists of 503,911 elements and 93,390 nodes. During flexion, extension, lateral bending, and axial rotation modes, the intact model's angular intersegmental range of motion was in good agreement with the results reported from the literature. The postoperative model after the three-segment laminectomy and the reconstructive model after applying the four LSF techniques were established based on the validated intact model. The stress distribution for the Magerl and Roy-Camille groups were more dispersive, and the maximum von Mises stress levels were lower than the other two groups in various conditions. The LSF techniques of Magerl and Roy-Camille are safer methods for stabilizing the lower cervical spine. Therefore, these methods potentially have a lower risk of fixation fracture.

Concomitant intramedullary arteriovenous malformation and a vertebral hemangioma of cervical spine discovered by a pathologic fracture during bicycle accident.

PubMed

Ayhan, Selim; Palaoglu, Selcuk; Geyik, Serdar; Saatci, Isil; Onal, Mehmet Bulent

2015-01-01

Spinal intramedullary arteriovenous malformations are uncommon and a challenging type of neurosurgical entities. They are rarely located to cervical segment. On the other hand, although hemangiomas are relatively common bone tumors, cervical involvement is again rare and clinically significant ones are infrequent. A 14 year-old-male patient referred to an academic tertiary care unit and presented with neck pain and left hand weakness. Neurological examination revealed motor strength deficit at intrinsic muscles and hyperesthesia at the left hand. Furthermore the pathological reflexes were positive on the left hand side. Imaging studies showed compression fracture, lytic changes resembling a hemangioma at C7 vertebra, and also an intramedullary vascular pathology at C5-6 level which was shown to be an intradural-intramedullary arteriovenous malformation (AVM) on digital subtraction angiography. Based on neurological and radiological findings, the decision was to treat the patient. After embolization of the AVM, the neurological condition of the patient deteriorated and immediate MRI scan of the cervical spine revealed edema of the spinal cord at the C5-6 level. Thus an emergent surgery was performed and C5-6-7 laminectomies with C5-T2 posterior fixation and arthrodesis were implemented. A second stage operation was carried out as C7 corpectomy with a distractable titanium cage 2 weeks after initial surgery. A follow-up evaluation at five years revealed 4/5 motor strength on his left intrinsic hand muscles and mild hyperactive deep tendon reflexes. Imaging studies at the postoperative period showed stable placement of the construct and no evidence of contrast enhancement at the C5-6 level inside the spinal cord. A rare case of multiple pathologies affecting the cervical spine, coincidentally diagnosed after a pathological fracture during a bicycle accident as vertebral hemangioma and intradural-intramedullary AVM that was successfully treated with early detection, have been presented. One should assess such patients under multidisciplinary fashion and treat on a case-by-case basis for achieving the best results in patient care.

Sexual intercourse for cervical ripening and induction of labour.

PubMed

Kavanagh, J; Kelly, A J; Thomas, J

2001-01-01

The role of prostaglandins for cervical ripening and induction of labour has been examined extensively. Human semen is the biological source that is presumed to contain the highest prostaglandin concentration. The role of sexual intercourse in the initiation of labour is uncertain. The action of sexual intercourse in stimulating labour is unclear, it may in part be due to the physical stimulation of the lower uterine segment, or endogenous release of oxytocin as a result of orgasm or from the direct action of prostaglandins in semen. Furthermore nipple stimulation may be part of the process of initiation. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. To determine the effects of sexual intercourse for third trimester cervical ripening or induction of labour in comparison with other methods of induction. The Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled Trials Register and bibliographies of relevant papers. Last searched: November 2000. (1) clinical trials comparing sexual intercourse for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random allocation to the treatment or control group; (3) adequate allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusion. A strategy has been developed to deal with the large volume and complexity of trial data relating to labour induction. This involves a two-stage method of data extraction. There was one included study of 28 women which reported very limited data, from which no meaningful conclusions can be drawn. The role of sexual intercourse as a method of induction of labour is uncertain. Any future trials investigating sexual intercourse as a method of induction need to be of sufficient power to detect clinically relevant differences in standard outcomes. However, it may prove difficult to standardise sexual intercourse as an intervention to allow meaningful comparisons with other methods of induction of labour.

Four lateral mass screw fixation techniques in lower cervical spine following laminectomy: a finite element analysis study of stress distribution

PubMed Central

2014-01-01

Background Lateral mass screw fixation (LSF) techniques have been widely used for reconstructing and stabilizing the cervical spine; however, complications may result depending on the choice of surgeon. There are only a few reports related to LSF applications, even though fracture fixation has become a severe complication. This study establishes the three-dimensional finite element model of the lower cervical spine, and compares the stress distribution of the four LSF techniques (Magerl, Roy-Camille, Anderson, and An), following laminectomy -- to explore the risks of rupture after fixation. Method CT scans were performed on a healthy adult female volunteer, and Digital imaging and communication in medicine (Dicom) data was obtained. Mimics 10.01, Geomagic Studio 12.0, Solidworks 2012, HyperMesh 10.1 and Abaqus 6.12 software programs were used to establish the intact model of the lower cervical spines (C3-C7), a postoperative model after laminectomy, and a reconstructive model after applying the LSF techniques. A compressive preload of 74 N combined with a pure moment of 1.8 Nm was applied to the intact and reconstructive model, simulating normal flexion, extension, lateral bending, and axial rotation. The stress distribution of the four LSF techniques was compared by analyzing the maximum von Mises stress. Result The three-dimensional finite element model of the intact C3-C7 vertebrae was successfully established. This model consists of 503,911 elements and 93,390 nodes. During flexion, extension, lateral bending, and axial rotation modes, the intact model’s angular intersegmental range of motion was in good agreement with the results reported from the literature. The postoperative model after the three-segment laminectomy and the reconstructive model after applying the four LSF techniques were established based on the validated intact model. The stress distribution for the Magerl and Roy-Camille groups were more dispersive, and the maximum von Mises stress levels were lower than the other two groups in various conditions. Conclusion The LSF techniques of Magerl and Roy-Camille are safer methods for stabilizing the lower cervical spine. Therefore, these methods potentially have a lower risk of fixation fracture. PMID:25106498

Evaluation of electrical nerve stimulation for epidural catheter positioning in the dog.

PubMed

Garcia-Pereira, Fernando L; Sanders, Robert; Shih, Andre C; Sonea, Ioana M; Hauptman, Joseph G

2013-09-01

To evaluate the accuracy of epidural catheter placement at different levels of the spinal cord guided solely by electrical nerve stimulation and resultant segmental muscle contraction. Prospective, experiment. Six male and two female Beagles, age (1 ± 0.17 years) and weight (12.9 ± 1.1 kg). Animals were anesthetized with propofol and maintained with isoflurane. An insulated epidural needle was used to reach the lumbosacral epidural space. A Tsui epidural catheter was inserted and connected to a nerve stimulator (1.0 mA, 0.1 ms, 2 Hz) to assess positioning of the tip at specific spinal cord segments. The catheter was advanced to three different levels of the spinal cord: lumbar (L2-L5), thoracic (T5-T10) and cervical (C4-C6). Subcutaneous needles were previously placed at these spinal levels and the catheter was advanced to match the needle location, guided only by corresponding muscle contractions. Catheter position was verified by fluoroscopy. If catheter tip and needle were at the same vertebral body a score of zero was assigned. When catheter tip was cranial or caudal to the needle, positive or negative numbers, respectively, corresponding to the number of vertebrae between them, were assigned. The mean and standard deviation of the number of vertebrae between catheter tip and needle were calculated to assess accuracy. Results are given as mean ± SD. The catheter position in relation to the needle was within 0.3 ± 2.0 vertebral bodies. Positive predictive values (PPV) were 57%, 83% and 71% for lumbar, thoracic and cervical regions respectively. Overall PPV was 70%. No significant difference in PPV among regions was found. Placement of an epidural catheter at specific spinal levels using electrical nerve stimulation was feasible without radiographic assistance in dogs. Two vertebral bodies difference from the target site may be clinically acceptable when performing segmental epidural regional anesthesia. © 2013 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

Cervical spinal epidural arteriovenous fistula with coexisting spinal anterior spinal artery aneurysm presenting as subarachnoid hemorrhage--case report.

PubMed

Nakagawa, Ichiro; Park, Hun-Soo; Hironaka, Yasuo; Wada, Takeshi; Kichikawa, Kimihiko; Nakase, Hiroyuki

2014-01-01

Hemorrhagic presentation of spinal epidural arteriovenous fistulas (AVFs) is rare in patients with cervical spinal vascular lesions. The present report describes a patient with cervical spine epidural AVFs associated with anterior spinal artery aneurysm at the same vertebral level presenting with subarachnoid hemorrhage. A 54-year-old man presented with sudden onset of headache. Computed tomography of the head showed subarachnoid hemorrhage. Diagnostic angiography revealed an epidural AVF located at the C1-2 level that was fed mainly by the dorsal somatic branches of the segmental arteries from the radicular artery and anterior spinal artery. This AVF drained only into the epidural veins without perimedullary venous reflux. Further, there was a 4-mm anterior spinal artery aneurysm in the vicinity of the fistula that was thought to be the cause of the hemorrhage. Endovascular transarterial fistulas embolization from the right radicular artery was performed to eliminate the AVF and to reduce hemodynamic stress on the aneurysm. No new symptoms developed after the treatment and discharged without neurological deficits. The aneurysm was noted to be reduced in size after the treatment and totally disappeared by 1 year later, according to follow-up angiography. Anterior spinal artery aneurysm from a separate vascular distribution may coexist with spinal epidural AVFs. In the setting of spinal subarachnoid hemorrhage, comprehensive imaging is indicated to rule out such lesions. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

S-wave attenuation structure beneath the northern Izu-Bonin arc

NASA Astrophysics Data System (ADS)

Takahashi, Tsutomu; Obana, Koichiro; Kodaira, Shuichi

2016-04-01

To understand temperature structure or magma distribution in the crust and uppermost mantle, it is essential to know their attenuation structure. This study estimated the 3-D S-wave attenuation structure in the crust and uppermost mantle at the northern Izu-Bonin arc, taking into account the apparent attenuation due to multiple forward scattering. In the uppermost mantle, two areas of high seismic attenuation (high Q -1) imaged beneath the volcanic front were mostly colocated with low-velocity anomalies. This coincidence suggests that these high- Q -1 areas in low-velocity zones are the most likely candidates for high-temperature regions beneath volcanoes. The distribution of random inhomogeneities indicated the presence of three anomalies beneath the volcanic front: Two were in high- Q -1 areas but the third was in a moderate- Q -1 area, indicating a low correlation between random inhomogeneities and Q -1. All three anomalies of random inhomogeneities were rich in short-wavelength spectra. The most probable interpretation of such spectra is the presence of volcanic rock, which would be related to accumulated magma intrusion during episodes of volcanic activity. Therefore, the different distributions of Q -1 and random inhomogeneities imply that the positions of hot regions in the uppermost mantle beneath this arc have changed temporally; therefore, they may provide important constraints on the evolutionary processes of arc crust and volcanoes.

Submandibular approach to the C2-3 disc level: microsurgical anatomy with clinical application.

PubMed

Russo, Antonino; Albanese, Erminia; Quiroga, Monica; Ulm, Arthur J

2009-04-01

Approaching the C2-3 disc level is challenging because of its location behind the mandible and the vital neurovascular structures overlying the area. The purpose of this study was to illustrate in a stepwise fashion the microsurgical anatomy of the submandibular approach to the C2-3 disc. Ten adult formalin-fixed cadaveric specimens (20 sides) were studied. Particular attention was paid to the structures limiting the exposure. The authors measured the distance between the inferior border of the mandible and the marginal mandibular branch of the facial nerve running inferior to the mandible, the distance between the horizontal segment of the hypoglossal nerve and the hyoid bone, and the distance between the horizontal segment of the hypoglossal nerve and the mandible. They compared the location of the superior laryngeal nerve with regard to the submandibular and the standard Smith-Robinson approaches. A clinical case illustrating the usefulness of the surgical technique in this region is presented. The mean distance between the inferior border of the mandible and the lowest point of the marginal mandibular branch of the facial nerve was 6.7 +/- 1.69 mm. The hypoglossal nerve's mean distance above the hyoid bone was 8.4 +/- 1.78 mm and below the mandible was 19.6 +/- 6.39 mm. The internal branch of the superior laryngeal nerve, with respect to the cervical spine, always entered the thyrohyoid membrane just inferior to the C-3 vertebral body. The superior laryngeal nerve was found to be an impediment to approaching the C2-3 disc through the standard Smith-Robinson approach. The submandibular approach provides excellent exposure, with a perpendicular view of the C2-3 disc level. This approach is one of the options to be considered when dealing with high cervical pathologies.

Evaluation of the interaction between sodium hypochlorite and several formulations containing chlorhexidine and its effect on the radicular dentin--SEM and push-out bond strength analysis.

PubMed

Graziele Magro, Miriam; Kuga, Milton Carlos; Regina Victorino, Keli; Vázquez-Garcia, Fernando Antonio; Aranda-Garcia, Arturo Javier; Faria-Junior, Norberto Batista; Faria, Gisele; Luis Shinohara, André

2014-01-01

The aim of the current study was to evaluate the presence of debris and smear layer after endodontic irrigation with different formulations of 2% chlorhexidine gluconate (CHX) and its effects on the push-out bond strength of an epoxy-based sealer on the radicular dentin. One hundred extracted human canines were prepared to F5 instrument and irrigated with 2.5% sodium hypochlorite and 17% ethylenediaminetetraacetic acid. Fifty teeth were divided into five groups (n = 10), according to the final irrigation protocol with different 2% CHX formulations: G1 (control, no final rinse irrigation), G2 (CHX solution), G3 (CHX gel), G4 (Concepsis), and G5 (CHX Plus). In sequence, the specimens were submitted to scanning electron microscopy (SEM) analysis, in the cervical-medium and medium-apical segments, to evaluate the presence of debris and smear layer. The other 50 teeth were treated equally to a SEM study, but with the root canals filled with an epoxy-based endodontic sealer and submitted to a push-out bond strength test, in the cervical, middle, and apical thirds. G2, G3, G4, and G5 provided higher precipitation of the debris and smear layer than G1 (P < 0.05), but these groups were similar to each other (P > 0.05), in both segments. The values obtained in the push out test did not differ between groups, independent of the radicular third (P > 0.05). The CHXs formulations caused precipitation of the debris and smear layer on the radicular dentin, but these residues did not interfere in the push-out bond strength of the epoxy-based sealer. Copyright © 2013 Wiley Periodicals, Inc.

RSA in Spine: A Review.

PubMed

Humadi, Ali; Dawood, Sulaf; Halldin, Klas; Freeman, Brian

2017-12-01

Systematic review of literature. This systematic review was conducted to investigate the accuracy of radiostereometric analysis (RSA), its assessment of spinal motion and disorders, and to investigate the limitations of this technique in spine assessment. Systematic review in all current literature to invesigate the role of RSA in spine. The results of this review concluded that RSA is a very powerful tool to detect small changes between 2 rigid bodies such as a vertebral segment. The technique is described for animal and human studies for cervical and lumbar spine and can be used to analyze range of motion, inducible displacement, and fusion of segments. However, there are a few disadvantages with the technique; RSA percutaneous procedure needs to be performed to implant the markers (and cannot be used preoperatively), one needs a specific knowledge to handle data and interpret the results, and is relatively time consuming and expensive. RSA should be looked at as a very powerful research instrument and there are many questions suitable for RSA studies.

RSA in Spine: A Review

PubMed Central

Dawood, Sulaf; Halldin, Klas; Freeman, Brian

2017-01-01

Study Design: Systematic review of literature. Objectives: This systematic review was conducted to investigate the accuracy of radiostereometric analysis (RSA), its assessment of spinal motion and disorders, and to investigate the limitations of this technique in spine assessment. Methods: Systematic review in all current literature to invesigate the role of RSA in spine. Results: The results of this review concluded that RSA is a very powerful tool to detect small changes between 2 rigid bodies such as a vertebral segment. The technique is described for animal and human studies for cervical and lumbar spine and can be used to analyze range of motion, inducible displacement, and fusion of segments. However, there are a few disadvantages with the technique; RSA percutaneous procedure needs to be performed to implant the markers (and cannot be used preoperatively), one needs a specific knowledge to handle data and interpret the results, and is relatively time consuming and expensive. Conclusions: RSA should be looked at as a very powerful research instrument and there are many questions suitable for RSA studies. PMID:29238647

Biotinylated dextran amine anterograde tracing of the canine corticospinal tract.

PubMed

Han, Xiao; Lv, Guangming; Wu, Huiqun; Ji, Dafeng; Sun, Zhou; Li, Yaofu; Tang, Lemin

2012-04-15

In this study, biotinylated dextran amine (BDA) was microinjected into the left cortical motor area of the canine brain. Fluorescence microscopy results showed that a large amount of BDA-labeled pyramidal cells were visible in the left cortical motor area after injection. In the left medulla oblongata, the BDA-labeled corticospinal tract was evenly distributed, with green fluorescence that had a clear boundary with the surrounding tissue. The BDA-positive corticospinal tract entered into the right lateral funiculus of the spinal cord and descended into the posterior part of the right lateral funiculus, close to the posterior horn, from cervical to sacral segments. There was a small amount of green fluorescence in the sacral segment. The distribution of BDA labeling in the canine central nervous system was consistent with the course of the corticospinal tract. Fluorescence labeling for BDA gradually diminished with time after injection. Our findings indicate that the BDA anterograde tracing technique can be used to visualize the localization and trajectory of the corticospinal tract in the canine central nervous system.

Eight good reasons why the uppermost mantle could be magnetic

NASA Astrophysics Data System (ADS)

Ferre, E. C.; Friedman, S. A.; Martin Hernandez, F.; Till, J. L.; Ionov, D. A.; Conder, J. A.

2012-12-01

The launch of Magsat in 1979 prompted a broad magnetic investigation of mantle xenoliths (Wasilewski et al., 1979). The study concluded that no magnetic remanence existed in the uppermost mantle and that even if present, such sources would be at temperatures too high to contribute to long wavelength magnetic anomalies (LWMA). However, new collections of unaltered mantle xenoliths from four different tectonic settings, along with updated views on the sources of LWMA and modern petrologic constraints on fO2 in the mantle indicate that the uppermost mantle could, in certain cases, contain ferromagnetic minerals. 1. The analysis of some LWMA over areas such as, for example, Bangui in the Central African Craton, the Cascadia subduction zone and serpentinized oceanic lithosphere suggest magnetic sources in the uppermost mantle. 2. The most common ferromagnetic phase in the uppermost mantle is pure magnetite, which has a pressure-corrected Curie temperature at 10 kbars of 600C instead of the generally used value of 580C. Assuming 30 km-thick continental crust, and crustal and mantle geotherms of 15C/km and 5C/km, respectively, the 600C Curie temperature implies the existence of a 30 km-thick layer of mantle rocks, whose remanent and induced magnetizations could contribute to LWMA. The thickness of this layer decreases to about 15 km for a 35 km-thick crust. 3. The uppermost mantle is cooler than 600C in some tectonic settings, including Archean and Proterozoic shields (>350C), subduction zones (>300C) and old oceanic basins (>250C). 4. Recently investigated sets of unaltered mantle xenoliths contain pure SD and PSD magnetite inclusions exsolved in olivine and pyroxene. The fact that these magnetite grains are not associated with any alteration phases, such as serpentine, and exhibit a subhedral shape, demonstrates that they formed in equilibrium with the host silicate. 5. The ascent of mantle xenoliths in volcanic conduits through cratons and subduction zones occurs in less than a day. Numerical models of Fe diffusion in silicates suggest that it is unlikely for exsolved magnetite grains to reach greater than superparamagnetic sizes within this time frame. 6. Demagnetization of natural remanent magnetization (NRM) of unaltered mantle xenoliths unambiguously indicates only a single component. The demagnetization of NRM spectra resembles that of laboratory-imparted anhysteretic remanent magnetizations, suggesting that the NRM is of thermal origin, and most likely acquired upon cooling at the Earth's surface. Yet mantle peridotites had to be magnetized before extraction from the mantle source. 7. Modern experimental data suggest that the wüstite-magnetite oxygen buffer and the fayalite-magnetite-quartz oxygen buffer extend several tens of km at depth within the uppermost mantle. Modern petrologic models also indicate that fO2 in the uppermost mantle varies significantly with tectonic setting. 8. The magnetic properties of mantle xenoliths vary consistently across island arc, craton, hot spot and mantle plume regions. The intensity of their NRMs appear to be influenced by their tectonic setting, in accordance with petrologic models. In conclusion, the model of a uniformaly non-magnetic mantle no longer agrees with multiple lines of evidence and should be revisited, especially because the most strongly magnetic xenoliths originate from cold geotherm settings.

EUI1, encoding a putative cytochrome P450 monooxygenase, regulates internode elongation by modulating gibberellin responses in rice.

PubMed

Luo, Anding; Qian, Qian; Yin, Hengfu; Liu, Xiaoqiang; Yin, Changxi; Lan, Ying; Tang, Jiuyou; Tang, Zuoshun; Cao, Shouyun; Wang, Xiujie; Xia, Kai; Fu, Xiangdong; Luo, Da; Chu, Chengcai

2006-02-01

Elongation of rice internodes is one of the most important agronomic traits, which determines the plant height and underlies the grain yield. It has been shown that the elongation of internodes is under genetic control, and various factors are implicated in the process. Here, we report a detailed characterization of an elongated uppermost internode1 (eui1) mutant, which has been used in hybrid rice breeding. In the eui1-2 mutant, the cell lengths in the uppermost internodes are significantly longer than that of wild type and thus give rise to the elongated uppermost internode. It was found that the level of active gibberellin was elevated in the mutant, whereas its growth in response to gibberellin is similar to that of the wild type, suggesting that the higher level accumulation of gibberellin in the eui1 mutant causes the abnormal elongation of the uppermost internode. Consistently, the expression levels of several genes which encode gibberellin biosynthesis enzymes were altered. We cloned the EUI1 gene, which encodes a putative cytochrome P450 monooxygenase, by map-based cloning and found that EUI1 was weakly expressed in most tissues, but preferentially in young panicles. To confirm its function, transgenic experiments with different constructs of EUI1 were conducted. Overexpression of EUI1 gave rise to the gibberellin-deficient-like phenotypes, which could be partially reversed by supplementation with gibberellin. Furthermore, apart from the alteration of expression levels of the gibberellin biosynthesis genes, accumulation of SLR1 protein was found in the overexpressing transgenic plants, indicating that the expression level of EUI1 is implicated in both gibberellin-mediated SLR1 destruction and a feedback regulation in gibberellin biosynthesis. Therefore, we proposed that EUI1 plays a negative role in gibberellin-mediated regulation of cell elongation in the uppermost internode of rice.

DIFFUSION PUMP

DOEpatents

Levenson, L.

1963-09-01

A high-vacuum diffusion pump is described, featuring a novel housing geometry for enhancing pumping speed. An upright, cylindrical lower housing portion is surmounted by a concentric, upright, cylindrical upper housing portion of substantially larger diameter; an uppermost nozzle, disposed concentrically within the upper portion, is adapted to eject downwardly a conical sheet of liquid outwardly to impinge upon the uppermost extremity of the interior wall of the lower portion. Preferably this nozzle is mounted upon a pedestal rising coaxially from within the lower portion and projecting up into said upper portion. (AEC)

Differential segmental growth of the vertebral column of the rat (Rattus norvegicus).

PubMed

Bergmann, Philip J; Melin, Amanda D; Russell, Anthony P

2006-01-01

Despite the pervasive occurrence of segmental morphologies in the animal kingdom, the study of segmental growth is almost entirely lacking, but may have significant implications for understanding the development of these organisms. We investigate the segmental and regional growth of the entire vertebral column of the rat (Rattus norvegicus) by fitting a Gompertz curve to length and age data for each vertebra and each vertebral region. Regional lengths are calculated by summing constituent vertebral lengths and intervertebral space lengths for cervical, thoracic, lumbar, sacral, and caudal regions. Gompertz curves allow for the estimation of parameters representing neonatal and adult vertebral and regional lengths, as well as initial growth rate and the rate of exponential growth decay. Findings demonstrate differences between neonatal and adult rats in terms of relative vertebral lengths, and differential growth rates between sequential vertebrae and vertebral regions. Specifically, relative differences in the length of vertebrae indicate increasing differences caudad. Vertebral length in neonates increases from the atlas to the middle of the thoracic series and decreases in length caudad, while adult vertebral lengths tend to increase caudad. There is also a general trend of increasing vertebral and regional initial growth and rate of growth decay caudad. Anteroposterior patterns of growth are sexually dimorphic, with males having longer vertebrae than females at any given age. Differences are more pronounced (a) increasingly caudad along the body axis, and (b) in adulthood than in neonates. Elucidated patterns of growth are influenced by a combination of developmental, functional, and genetic factors.

Geologic map of the Basque-Cantabrian Basin and a new tectonic interpretation of the Basque Arc

NASA Astrophysics Data System (ADS)

Ábalos, B.

2016-11-01

A new printable 1/200.000 bedrock geological map of the onshore Basque-Cantabrian Basin is presented, aimed to contribute to future geologic developments in the central segment of the Pyrenean-Cantabrian Alpine orogenic system. It is accompanied in separate appendixes by a historic report on the precedent geological maps and by a compilation above 350 bibliographic citations of maps and academic reports (usually overlooked or ignored) that are central to this contribution. Structural scrutiny of the map permits to propose a new tectonic interpretation of the Basque Arc, implementing previously published partial reconstructions. It is presented as a printable 1/400.000 tectonic map. The Basque Arc consists of various thrust slices that can expose at the surface basement rocks (Palaeozoic to Lower Triassic) and their sedimentary cover (uppermost Triassic to Tertiary), from which they are detached by intervening (Upper Triassic) evaporites and associated rocks. The slice-bounding thrusts are in most cases reactivated normal faults active during Meso-Cenozoic sedimentation that can be readily related to basement discontinuities generated during the Hercynian orogeny.

Intermediate clinical and radiological results of cervical TDR (Mobi-C®) with up to 2 years of follow-up

PubMed Central

Beaurain, J.; Bernard, P.; Dufour, T.; Fuentes, J. M.; Hovorka, I.; Huppert, J.; Steib, J. P.; Vital, J. M.; Aubourg, L.

2009-01-01

The interest in cervical total disc replacement (TDR) as an alternative to the so-far gold standard in the surgical treatment of degenerative disc disease (DDD), e.g anterior cervical discectomy and fusion (ACDF), is growing very rapidly. Many authors have established the fact that ACDF may result in progressive degeneration in adjacent segments. On the contrary, but still theoretically, preservation of motion with TDR at the surgically treated level may potentially reduce the occurrence of adjacent-level degeneration (ALD). The authors report the intermediate results of an undergoing multicentre prospective study of TDR with Mobi-C® prosthesis. The aim of the study was to assess the safety and efficacy of the device in the treatment of DDD and secondary to evaluate the radiological status of adjacent levels and the occurrence of ossifications, at 2-year follow-up (FU). 76 patients have performed their 2-year FU visit and have been analyzed clinically and radiologically. Clinical outcomes (NDI, VAS, SF-36) and ROM measurements were analyzed pre-operatively and at the different post-operative time-points. Complications and re-operations were also assessed. Occurrences of heterotopic ossifications (HOs) and of adjacent disc degeneration radiographic changes have been analyzed from 2-year FU X-rays. The mean NDI and VAS scores for arm and neck are reduced significantly at each post-operative time-point compared to pre-operative condition. Motion is preserved over the time at index levels (mean ROM = 9° at 2 years) and 85.5% of the segments are mobile at 2 years. HOs are responsible for the fusion of 6/76 levels at 2 years. However, presence of HO does not alter the clinical outcomes. The occurrence rate of radiological signs of ALD is very low at 2 years (9.1%). There has been no subsidence, no expulsion and no sub-luxation of the implant. Finally, after 2 years, 91% of the patients assume that they would undergo the procedure again. These intermediate results of TDR with Mobi-C® are very encouraging and seem to confirm the efficacy and the safety of the device. Regarding the preservation of the status of the adjacent levels, the results of this unconstrained device are encouraging, but longer FU studies are needed to prove it. PMID:19434431

[Possibilities and results of surgical treatment of benign tracheoesophageal fistula].

PubMed

Krajc, T; Janík, M; Lucenic, M; Benej, R; Harustiak, S

2010-08-01

Review of literature and a single-institution retrospective analysis of possibilities and results of various surgical techniques in treatment of benign tracheoesophageal fistula (TEF). Between 1995 and 2010, 26 patients with benign tracheoesophageal fistula of various etiology underwent surgical treatment at the Department of Thoracic Surgery of Slovak Medical University and Faculty Hospital in Bratislava. The majority of patients had a postintubation TEF (21 cases), two fistulas were of traumatic origin, one iatrogenic, one congenital with adulthood manifestation and one tracheo-neoesophageal (TNEF) following an esophagectomy for carcinoma via extended cervical approach with lymphadenectomy and sternal retraction adpoted from transcervical extended mediastinal lymphadenectomy. We review the possible means of surgical treatment of TEF, of which we most frequently used segmental tracheal resection with end-to-end anastomosis and a non-overlying suture of the esophageal defect without muscle flap interposition (16 patients), transsection of the fistula with muscular flap interposition via cervical (2 patients) or transthoracic (1 patient) approach; or a T-tube insertion with (1 patient) or without (5 patients) discision and suture of the TEF. The only tracheo-neoesophageal fistula in our experience had been treated by neoesophagectomy, covering of tracheal defect by intercostal muscle flap and cervical esophagostomy. Short- and long-term results of TEF treatment in our institution have been favourable, with perioperative mortality of 3.8% (the patient with tracheo-neoesophageal fistula). Morbidity included 1 partial tracheal anastomotic dehiscence, 3 temporary left recurrent nerve palsies, temporary deglutition disorders (15 patients), tracheal anastomosis granulations in 1 patient and 2 wound infections. Out of 26 patients 15 (58%) are being followed-up on a regular basis, all with good (12 patients) or satisfactory (3 patients) functional results. In the paper we analyze the advantages and disadvantages of various techniques and their alternatives in the treatment of TEF. As the most reliable and suitable solution for patients with postintubation TEF, breathing spontaneously and with acceptable nutritional status, we favour segmental trachea resection with end-to-end anastomosis and esophageal suture without muscle interposition, regardless of presence of concomitant tracheal stenosis. Fistulae of other etiologies require diverse approaches, especially tailored with respect to their location. Management of tracheo-neoesophageal fistula following esophagectomy for carcinoma is extremely demanding. Therefore, it is crucial to adhere to basic rules of prevention of such benign but potentially fatal entities as TEF and TNEF.

The stretching amplitude and thermal regime of the lithosphere in the nonvolcanic passive margin of Antarctica in the Mawson Sea region

NASA Astrophysics Data System (ADS)

Galushkin, Yu. I.; Leitchenkov, G. L.; Guseva, Yu. B.; Dubinin, E. P.

2018-01-01

The burial history and thermal evolution of the lithosphere within the passive nonvolcanic Antarctic margin in the region of the Mawson Sea are numerically reconstructed for the margin areas along the seismic profile 5909 with the use of the GALO basin modeling system. The amplitudes of the lithosphere stretching at the different stages of continental rifting which took place from 160 to 90 Ma ago are calculated from the geophysical estimates of the thickness of the consolidated crust and the tectonic analysis of the variations in the thickness of the sedimentary cover and sea depths during the evolution of the basin. It is hypothesized that the formation of the recent sedimentary section sequence in the studied region of the Antarctic margin began 140 Ma ago on a basement that was thinned by a factor of 1.6 to 4.5 during the first episode of margin stretching (160-140 Ma) under a fairly high heat flux. The reconstruction of the thermal regime of the lithosphere has shown that the mantle rocks could occur within the temperature interval of serpentinization and simultaneously within the time interval of lithospheric stretching (-160 < t <-90 Ma) only within separate segments of profile 5909 in the Mawson Sea. The calculations of the rock strength distribution with depth by the example of the section of pseudowell 4 have shown that a significant part of the crust and uppermost mantle fall here in the region of brittle deformations in the most recent period of lithosphere stretching (-104 to-90 Ma ago). The younger basin segments of profile 5909 in the region of pseudowells 5 and 6 are characterized by a high heat flux, and the formation of through-thickness brittle fractures in these zones is less probable. However, serpentinization could take place in these areas as in the other margin segments at the stage of presedimentation ultra slow basement stretching.

Outcomes Evaluation of Zero-Profile Devices Compared to Stand-Alone PEEK Cages for the Treatment of Three- and Four-Level Cervical Disc Disease.

PubMed

Gerszten, Peter C; Paschel, Erin; Mashaly, Hazem; Sabry, Hatem; Jalalod'din, Hasan; Saoud, Khaled

2016-09-10

Anterior cervical discectomy and fusion (ACDF) is a well-accepted treatment option for patients with cervical spine disease. Three- and four-level discectomies are known to be associated with a higher complication rate and lower fusion rate than single-level surgery. This study was performed to evaluate and compare zero-profile fixation and stand-alone PEEK cages for three- and four-level ACDF. Two cohorts of patients who underwent ACDF for the treatment of three- and four-level disease were compared. Thirty-three patients underwent implantation of zero-profile devices that included titanium screw fixation (Group A). Thirty-five patients underwent implantation of stand-alone PEEK cages without any form of screw fixation (Group B). In Group A, twenty-seven patients underwent a three-level and six patients a four-level ACDF, with a total of 105 levels. In Group B, thirty patients underwent a three-level and five patients underwent a four-level ACDF, with a total number of 110 levels. In Group A, the mean preoperative visual analog scale score (VAS) for arm pain was 6.4 (range 3-8), and the mean postoperative VAS for arm pain decreased to 2.5 (range 1-7). In group B, the mean preoperative VAS of arm pain was 7.1 (range 3-10), and the mean postoperative VAS of arm pain decreased to 2 (range 0-4). In Group A, four patients (12%) developed dysphagia, and in Group B, three patients (9%) developed dysphagia.  Conclusions: This study found zero-profile instrumentation and PEEK cages to be both safe and effective for patients who underwent three- and four-level ACDF, comparable to reported series using plate devices. Rates of dysphagia for the cohort were much lower than reports using plate devices. Zero-profile segmental fixation devices and PEEK cages may be considered as viable alternatives over plate fixation for patients requiring multi-level anterior cervical fusion surgery.

Comparison of plate-cage construct and stand-alone anchored spacer in the surgical treatment of three-level cervical spondylotic myelopathy: a preliminary clinical study.

PubMed

Shi, Sheng; Liu, Zu-De; Li, Xin-Feng; Qian, Lie; Zhong, Gui-Bin; Chen, Fang-Jing

2015-09-01

Although stand-alone cages were advocated to be superior to plate-cage construct (PCC) because of comparable clinical outcomes and fewer plate-related complications, cage dislocation and subsidence were frequently mentioned in multilevel fusion. There are some concerns about whether these issues can be effectively prevented in multilevel anterior cervical discectomy and fusion (ACDF) by stand-alone anchored spacer (SAAS). The aim was to compare clinical outcomes, radiologic parameters, and complications of PCC and SAAS in the treatment of three-level cervical spondylotic myelopathy (CSM). This was a retrospective comparative study. A total of 38 consecutive patients with three-level CSM (ACDF with PCC, 20 patients; ACDF with SAAS, 18 patients) were reviewed. Clinical outcomes were assessed using Japanese Orthopaedic Association and Neck Disability Index. The radiologic evaluations included cervical alignment (CA), segmental angle (SA), postoperative curvature loss (PCL), and incidence of subsidence. All the aforementioned parameters were compared before and after surgery between two groups. Besides, the aforementioned results were also compared between the two groups. The complications were also recorded. The mean follow-up period was 30.3 months. No significant differences were observed in clinical outcomes between the two groups (p>.05). Additionally, no significant differences existed in fusion rate between the two groups. There were significant differences in PCL of SA and CA and correction of SA between the two groups (p<.05). Besides, the incidence of subsidence (9 of 54 levels, 16.7%) was recorded in the SAAS group, and the potential of SAAS to reduce the incidence of postoperative dysphagia was not proven. No other complications were observed in this study. In the surgical treatment of three-level CSM, PCC is superior to SAAS in correction and maintenance of SA and avoiding cage subsidence, although the technique of ACDF with SAAS yielded encouraging clinical outcomes and high fusion rate. Copyright © 2015 Elsevier Inc. All rights reserved.

Biomechanical analyses of whiplash injuries using an experimental model.

PubMed

Yoganandan, Narayan; Pintar, Frank A; Cusick, Joseph F

2002-09-01

Neck pain and headaches are the two most common symptoms of whiplash. The working hypothesis is that pain originates from excessive motions in the upper and lower cervical segments. The research design used an intact human cadaver head-neck complex as an experimental model. The intact head-neck preparation was fixed at the thoracic end with the head unconstrained. Retroreflective targets were placed on the mastoid process, anterior regions of the vertebral bodies, and lateral masses at every spinal level. Whiplash loading was delivered using a mini-sled pendulum device. A six-axis load cell and an accelerometer were attached to the inferior fixation of the specimen. High-speed video cameras were used to obtain the kinematics. During the initial stages of loading, a transient decoupling of the head occurs with respect to the neck exhibiting a lag of the cranium. The upper cervical spine-head undergoes local flexion concomitant with a lag of the head while the lower column is in local extension. This establishes a reverse curvature to the head-neck complex. With continuing application of whiplash loading, the inertia of the head catches up with the neck. Later, the entire head-neck complex is under an extension mode with a single extension curvature. The lower cervical facet joint kinematics demonstrates varying local compression and sliding. While the anterior- and posterior-most regions of the facet joint slide, the posterior-most region of the joint compresses more than the anterior-most region. These varying kinematics at the two ends of the facet joint result in a pinching mechanism. Excessive flexion of the posterior upper cervical regions can be correlated to headaches. The pinching mechanism of the facet joints can be correlated to neck pain. The kinematics of the soft tissue-related structures explain the mechanism of these common whiplash associated disorders.

Long-term outcome after adjacent two-level anterior cervical discectomy and fusion using stand-alone plasmaphore-covered titanium cages.

PubMed

Marbacher, Serge; Hidalgo-Staub, Teresa; Kienzler, Jenny; Wüergler-Hauri, Carola; Landolt, Hans; Fandino, Javier

2015-05-01

Reports on long-term outcome of stand-alone contiguous two-level anterior cervical discectomy and fusion (ACDF) using stand-alone Plasmaphore-coated titanium cages (PCTCs) are rare, and data on follow-ups > 3 years are missing. To evaluate the long-term outcome of adjacent two-level microsurgical ACDF using stand-alone PCTC. A total of 33 consecutive patients presented with cervical degenerative disc disease (DDD) underwent contiguous two-level ACDF. Clinical long-term evaluation (mean: 61 ± 14 months) included documentation of neurologic deficits (motor deficits, sensory deficits, reflex status, and gait disturbance), neck pain, and radicular pain. Functional outcome was measured using the Odom criteria, patient-perceived outcome, and evaluation of work status. Radiographs were evaluated to assess intervertebral disc height, subsidence, level of fusion, sagittal balance, and implant position. Surgery was performed at levels C5-C6 and C6-C7 in 30 patients and at C4-C5 and C5-C6 in 3 (mean age: 50.1 ± 7.7 years). Symptoms and neurologic deficits improved as follows: neurologic deficits (pre: 100%; post: 36%), radicular pain (pre: 85%; post: 15%), and neck pain (pre: 94%; post: 33%). Excellent and good functional and subjective outcome was noted in 75%. Cage subsidence was found to be more prominent in the lower (52%) than the upper (36%) mobile cervical segment. Two-level fusion was documented in most patients (n = 29 [88%]). Kyphotic deformity occurred in two cases (n = 2 [6%]). Stand-alone contiguous two-level ACDF using PCPT proved to be effective, yielding good long-term clinical and functional outcomes. The relatively high rate of subsidence did not affect the good clinical and functional long-term outcome. Georg Thieme Verlag KG Stuttgart · New York.

Splint coals of the Central Appalachians: Petrographic and geochemical facies of the Peach Orchard No. 3 split coal bed, southern Magoffin County, Kentucky

USGS Publications Warehouse

Hower, James C.; Ruppert, Leslie F.

2011-01-01

The Bolsovian (Middle Pennsylvanian) Peach Orchard coal bed is one of the splint coals of the Central Appalachians. Splint coal is a name for the dull, inertinite-rich lithologies typical of coals of the region. The No. 3 Split was sampled at five locations in Magoffin County, Kentucky and analyzed for petrography and major and minor elements. The No. 3 Split coals contain semifusinite-rich lithologies, up to 48% (mineral-free basis) in one case. The nature of the semifusinite varies with position in the coal bed, containing more mineral matter of detrital origin in the uppermost durain. The maceral assemblage of these terminal durains is dominated by detrital fusinite and semifusinite, suggesting reworking of the maceral assemblage coincident with the deposition of the detrital minerals. However, a durain in the middle of the coal bed, while lithologically similar to the uppermost durains, has a degraded, macrinite-rich, texture. The inertinite macerals in the middle durain have less distinct edges than semifusinites in the uppermost terminal durains, suggesting degradation as a possible path to inertinite formation. The uppermost durain has higher ash and semifusinite contents at the eastern sites than at the western sites. The difference in the microscopic petrology indicates that megascopic petrology alone can be a deceptive indicator of depositional environments and that close attention must be paid to the individual macerals and their implications for the depositional setting, especially within the inertinite group.

Sn-wave velocity structure of the uppermost mantle beneath the Australian continent

NASA Astrophysics Data System (ADS)

Wei, Zhi; Kennett, Brian L. N.; Sun, Weijia

2018-06-01

We have extracted a data set of more than 5000 Sn traveltimes for source-station pairs within continental Australia, with 3-D source relocation using Pn arrivals to improve data consistency. We conduct tomographic inversion for S-wave-speed structure down to 100 km using the Fast Marching Tomography (FMTOMO) method for the whole Australian continent. We obtain a 3-D model with potential resolution of 3.0° × 3.0°. The new S-wave-speed model provides strong constraints on structure in a zone that was previously poorly characterized. The S velocities in the uppermost mantle are rather fast, with patterns of variation generally corresponding to those for Pn. We find strong heterogeneities of Swave speed in the uppermost mantle across the entire continent of Australia with a close relation to crustal geological features. For instance, the cratons in the western Australia usually have high S velocities (>4.70 km s-1), while the volcanic regions on the eastern margin of Australia are characterized by low S velocities (<4.40 km s-1). Exploiting an equivalent Pn inversion, we also determine the Vp/Vs ratios across the whole continent. We find that most of the uppermost mantle has Vp/Vs between 1.65 and 1.85, but with patches in central Australia and in the east with much higher Vp/Vs ratios. Distinctive local anomalies on the eastern margin may indicate the positions of remnants of mantle plumes.

Percutaneous Endoscopic Cervical Discectomy (PECD): An Analysis of Outcome, Causes of Reoperation.

PubMed

Oh, Hyeong Seok; Hwang, Byeong-Wook; Park, Sang-Joon; Hsieh, Chang-Sheng; Lee, Sang-Ho

2017-06-01

Percutaneous endoscopic cervical discectomy (PECD) is regarded as an effective treatment modality in cervical disc herniation, including radicular pain and lateral location of disc herniation. This study aimed to evaluate the clinical and radiologic outcomes of PECD along with the causes of reoperation and the technique itself. Between January 2007 and November 2012, 101 patients underwent PECD at the Busan Wooridul Hospital. Three patients underwent a 2-level PECD. The mean follow-up period was 34 months (range, 18-72 months). The mean age was 46.1 years; the most common operation was at the C5-C6 level (n = 45), followed by C6-C7 (n = 35), C4-C5 (n = 16), and C3-C4 (n = 8). The clinical outcomes were evaluated via the visual analog scale of the neck and arm according to the Neck Disability Index and the modified Macnab criteria. Among 101 patients, 12 underwent an additional operation at the index level. Five patients had aggravated stenosis by disc height narrowing, 4 had recurred disc, 2 had remained disc, and 1 had sustained symptoms. After PECD, there was a significant improvement in the visual analog scale and Neck Disability Index scores (P < 0.001). According to the modified Macnab criteria, excellent concordance was achieved in 65 patients, good in 22, fair in 2, and poor in 12. The reoperation performed on 12 patients improved their clinical outcomes. The mean duration was 4.8 months (2 days to 18 months) until reoperation. There were 3 PECD revisions, 3 artificial disc replacements, 2 corpectomies, 2 anterior cervical discectomies and fusion with cages, and 2 transfers to another hospital. The common feature was older age (P = 0.016) and male sex (P = 0.031). Preoperative radiologic findings were characterized by the foraminal disc (P = 0.04), disc degeneration at the index level (P = 0.05), combined bony spur (P = 0.001), concomitant adjacent level degeneration (P = 0.019), cervical kyphosis (P = 0.015), and segmental angle deterioration after PECD (P = 0.038). No statistical correlation was seen between the operation level and herniation size (P > 0.05). In total, 87% patients showed successful clinical outcome. Poor and fair outcomes at initial PECD were overcome by revision surgery, which improved outcomes. Although PECD is a promising minimally invasive procedure for cervical disc treatment, the indications for PECD should be considered carefully. Copyright © 2017 Elsevier Inc. All rights reserved.

Differential fMRI Activation Patterns to Noxious Heat and Tactile Stimuli in the Primate Spinal Cord

PubMed Central

Yang, Pai-Feng; Wang, Feng

2015-01-01

Mesoscale local functional organizations of the primate spinal cord are largely unknown. Using high-resolution fMRI at 9.4 T, we identified distinct interhorn and intersegment fMRI activation patterns to tactile versus nociceptive heat stimulation of digits in lightly anesthetized monkeys. Within a spinal segment, 8 Hz vibrotactile stimuli elicited predominantly fMRI activations in the middle part of ipsilateral dorsal horn (iDH), along with significantly weaker activations in ipsilateral (iVH) and contralateral (cVH) ventral horns. In contrast, nociceptive heat stimuli evoked widespread strong activations in the superficial part of iDH, as well as in iVH and contralateral dorsal (cDH) horns. As controls, only weak signal fluctuations were detected in the white matter. The iDH responded most strongly to both tactile and heat stimuli, whereas the cVH and cDH responded selectively to tactile versus nociceptive heat, respectively. Across spinal segments, iDH activations were detected in three consecutive segments in both tactile and heat conditions. Heat responses, however, were more extensive along the cord, with strong activations in iVH and cDH in two consecutive segments. Subsequent subunit B of cholera toxin tracer histology confirmed that the spinal segments showing fMRI activations indeed received afferent inputs from the stimulated digits. Comparisons of the fMRI signal time courses in early somatosensory area 3b and iDH revealed very similar hemodynamic stimulus–response functions. In summary, we identified with fMRI distinct segmental networks for the processing of tactile and nociceptive heat stimuli in the cervical spinal cord of nonhuman primates. SIGNIFICANCE STATEMENT This is the first fMRI demonstration of distinct intrasegmental and intersegmental nociceptive heat and touch processing circuits in the spinal cord of nonhuman primates. This study provides novel insights into the local functional organizations of the primate spinal cord for pain and touch, information that will be valuable for designing and optimizing therapeutic interventions for chronic pain management. PMID:26203144

Recurrent, nonmalignant tracheoesophageal fistulas and the need for surgical improvisation.

PubMed

Altorjay, Aron; Mucs, Mihály; Rüll, Miklós; Tihanyi, Zoltán; Hamvas, Balázs; Madácsy, László; Paál, Balázs

2010-06-01

Despite the many recent advances in thoracic surgery, the management of patients with recurrent, nonmalignant tracheoesophageal fistulas remains problematic, controversial, and challenging. Between 1998 and 2008, we treated 8 patients with RTEF. Closure of the original tracheoesophageal fistula had been attempted once in 5 patients, twice in 2 patients, and 4 times in 1 patient, all in different institutions. Four cases necessitated right posterolateral thoracotomy and cervical exposure, 2 cases cervical and abdominal incision, and 1 case right posterolateral thoracotomy, with abdominal and cervical exposure. With the exception of the 2 patients whose excluded esophagus was used to substitute for the trachea membranous wall, the damaged tracheal segment was removed. In general, a pedicled mediastinal pleural flap was pulled into the neck to increase the safety of the tracheal anastomosis formed with the trachea, and (or) to separate the suture lines of the two organs. A single intervention was sufficient for all 8 patients: no reoperation was necessary, and there was no perioperative mortality. Transient reflux, abdominal distention, and dyspnea in response to forced physical exertion occurred in 1 case each. Only 1 patient subsequently takes medication regularly for reflux disease. Separation initiated from the tracheal bifurcation, a pedicled mediastinal pleural flap pulled into the neck, a tracheal anastomosis sewn onto the cricoid cartilage with avoidance of its posterolateral elbow, a shaped Dumon stent (Novatech, Plan de Grasse, France) with an individually fenestrated tracheostomy cannula, and endoscopy-assisted, transhiatal vagal-preserving esophageal exclusion all served as successful elements of our surgical procedures. 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

[Clinical observation of 5 cases of diabetes insipidus complicated with skeletal fluorosis].

PubMed

Wang, Shuan-Chi; Tao, Xiao-Bing; Wang, Fang-Fang; Zhang, Nan

2017-07-25

To investigate the mechanism of diabetes insipidus complicated with skeletal fluorosis and the surgical treatment of spinal canal stenosis caused by skeletal fluorosis. From January 2000 to November 2011, 5 patients with diabetes insipidus complicated with skeletal fluorosis were treated with drug and cervical or thoracic posterior decompression including 2 males and 3 females with age of 35, 45, 47, 49, 55 years old respectively. The symptoms was mainly limb motor sensory disturbance accompanied by polyuria and polyuria. Imaging showed that cervical and thoracic multi-segmental continuous spinal stenosis. It was diagnosed with diabetes insipidus according to the symptoms and laboratory tests. According to the symptoms, the vertebral with problems were located and treated by posterior laminectomy decompression or the expansive open-door laminectomy. The recovery of neurological symptoms were recorded and the operation result were evaluate by JOA score improvement rate. The wound healed well in 5 cases, and 1 case of cervical axial pain was improved after symptomatic treatment. Five patients were followed up for 2 to 6 years with an average of 4 years. Numbness of limb and weakness symptoms of follow-up patients were significantly improved, muscle strength and acupuncture hypothyroidism were significantly improved compared with preoperative, the JOA score was significantly improved. At the final follow-up, the improvement rate got excellent results in 2 cases, good in 2 and fair in 1. Long-term high intake of fluoride can cause skeletal fluorosis in patients with diabetes insipidus. The posterior decompression is effective for the majority of spinal canal stenosis caused by skeletal fluorosis.

Spinal and pontine relay pathways mediating respiratory rhythm entrainment by limb proprioceptive inputs in the neonatal rat.

PubMed

Giraudin, Aurore; Le Bon-Jégo, Morgane; Cabirol, Marie-Jeanne; Simmers, John; Morin, Didier

2012-08-22

The coordination of locomotion and respiration is widespread among mammals, although the underlying neural mechanisms are still only partially understood. It was previously found in neonatal rat that cyclic electrical stimulation of spinal cervical and lumbar dorsal roots (DRs) can fully entrain (1:1 coupling) spontaneous respiratory activity expressed by the isolated brainstem/spinal cord. Here, we used a variety of preparations to determine the type of spinal sensory inputs responsible for this respiratory rhythm entrainment, and to establish the extent to which limb movement-activated feedback influences the medullary respiratory networks via direct or relayed ascending pathways. During in vivo overground locomotion, respiratory rhythm slowed and became coupled 1:1 with locomotion. In hindlimb-attached semi-isolated preparations, passive flexion-extension movements applied to a single hindlimb led to entrainment of fictive respiratory rhythmicity recorded in phrenic motoneurons, indicating that the recruitment of limb proprioceptive afferents could participate in the locomotor-respiratory coupling. Furthermore, in correspondence with the regionalization of spinal locomotor rhythm-generating circuitry, the stimulation of DRs at different segmental levels in isolated preparations revealed that cervical and lumbosacral proprioceptive inputs are more effective in this entraining influence than thoracic afferent pathways. Finally, blocking spinal synaptic transmission and using a combination of electrophysiology, calcium imaging and specific brainstem lesioning indicated that the ascending entraining signals from the cervical or lumbar limb afferents are transmitted across first-order synapses, probably monosynaptic, in the spinal cord. They are then conveyed to the brainstem respiratory centers via a brainstem pontine relay located in the parabrachial/Kölliker-Fuse nuclear complex.

Mobile colposcopy in urban and underserved suburban areas in Baja California

NASA Astrophysics Data System (ADS)

Madiedo, Marta; Contreras, Sonia; Villalobos, Octavio; Kahn, Bruce S.; Safir, Amit; Levitz, David

2016-03-01

Cervical cancer is the leading cause of cancer death for women in low resource settings, often affecting the most economically disenfranchised segment of the population. The key challenge with cervical cancer is the lack of an effective screening program for many of the at-risk, difficult-to-reach women. Outreach programs that utilize mobile clinics to increase access to screening and care in Baja California have been developed. However, many barriers such as quality assurance, efficient referral remained a challenge in this region. Visualization-based co-tests together with cytology (Pap smears) as a primary screen have been proposed. Here, the mobile colposcope of the enhanced visual assessment (EVA) is used to capture an image immediately following a Pap smear. EVA images were reviewed by expert colposcopists. Initial or preliminary data from pilot services showed that Pap false positives and Pap false negatives maybe reduced by expert review of EVA images. This suggests that reviewing of EVA images may be instrumental in catching inaccurate Pap results, thereby improving care. Thus, there is a need to further explore the benefits of using EVA as additional information when conducting Pap smear screenings.

Behavior of MORB magmas at uppermost mantle beneath a fast-spreading axis: an example from Wadi Fizh of the northern Oman ophiolite

NASA Astrophysics Data System (ADS)

Akizawa, Norikatsu; Arai, Shoji; Tamura, Akihiro

2012-10-01

Relationships of lithologies in uppermost mantle section of Oman ophiolite are highly complicated, harzburgites especially being closely associated with dunites, wehrlites, and gabbros. The petrology and geochemistry of the uppermost mantle section provide constrains on how MORB (mid-ocean ridge basalt) magmas migrate from the mantle to crust. We conducted detailed sampling at the uppermost mantle section of the northern Oman ophiolite (along Wadi Fizh), and it provides us with centimeter-scale lithological and mineral chemical heterogeneity. In particular, we found peculiar plagioclase-free harzburgites that have not been recorded from the current ocean floor, which contain high-Mg# [Mg/(Mg + Fe2+) atomic ratio] clinopyroxenes that are almost in equilibrium (saturated) with MORB in terms of REE concentrations. They are from the uppermost mantle section underlying the wehrlite-dunite layer (=Moho transition zone; MTZ) just beneath the layered gabbro. MORBs cannot be in equilibrium with harzburgites; however, we call the peculiar harzburgites as "MORB-saturated harzburgite" for simplicity in this paper. The MORB-saturated harzburgites exhibit slightly enriched mineralogy (e.g., spinels with higher Ti and ferric iron, and clinopyroxenes with higher Ti and Na) and contain slightly but clearly more abundant modal clinopyroxene (up to 3.5 vol.%) than ordinary Oman depleted harzburgites (less than 1 vol.% clinopyroxene), which are similar to abyssal harzburgites. Gabbro-clinopyroxenite bands, which were melt lenses beneath the ridge axis, are dominant around the MTZ. Detailed sampling around the gabbro-clinopyroxenite bands revealed that the MORB-saturated harzburgites appear around the bands. The interaction between a melt that was MORB-like and an ordinary harzburgite induced incongruent melting of orthopyroxenes in harzburgites, and the melt chromatographically intruded into the wall harzburgite and was modified to coexist with olivine and two pyroxenes at low melt/harzburgite ratios. The modified melt left clinopyroxene (not clinopyroxene + plagioclase as in plagioclase-impregnated abyssal harzburgite) to form the MORB-saturated harzburgites in the vicinity (harzburgite) of the fracture, which are left as gabbro-clinopyroxenite bands. This local modification mimics the whole lithological and chemical variation of the MTZ and makes chemical variation of MORB suite at fast-spreading ridge.

Efficacy of Zero-Profile Implant in Anterior Fusion to Treat Degenerative Cervical Spine Disease: Comparison with Techniques Using Bone Graft and Anterior Plating.

PubMed

Chang, Han; Baek, Dong-Hoon; Choi, Byung-Wan

2015-07-01

The efficacy of anterior fusion using zero-profile implant (Zero-P) in the surgical treatment of degenerative cervical disease was investigated through radiographic and clinical comparisons with existing treatments using autograft or allograft and anterior plating. A total of 130 patients who underwent anterior decompression and fusion for degenerative cervical spine disease with a follow-up of at least 1 year were analyzed retrospectively. The cases were divided into three groups: autograft and plate (38 cases, group A), allograft and plate (44 cases, group B), and Zero-P (48 cases, group C). Maintenance of lordosis, extent of subsidence, and fusion were evaluated radiologically and compared among preoperative, postoperative, and final follow-up time points. In addition, changes in Visual Analog Scale (VAS) and Neurologic Disability Index (NDI) scores and the presence of complications were evaluated for clinical analysis. Operation time was significantly less in group C (p = 0.007, 0.002). Maintenance of entire and segmental lordosis after surgery was better in groups A and B compared with group C (p = 0.002, 0.001); however, the extent of loss of lordosis from the surgery to the final follow-up did not show any significant differences. Regarding the extent of subsidence, the increase of height between the vertebral bodies after the surgery was 3.10, 2.89, and 2.68 mm in group A, group B, and group C, respectively (p = 0.14), and changed to - 1.27, - 2.41, and - 1.2 mm at the final follow-up (p = 0.012). VAS and NDI scores were improved from 7.2 to 3 and 34 to 12, respectively, but there were no significant differences. Nonunion occurred in two cases in both group B and group C. In terms of clinical complications, two cases of persistent donor site pain were found in group A; one case of persistent dysphagia was found in both group A and group B. Anterior cervical fusion using Zero-P has a shorter operation time and less subsidence compared with conventional surgical techniques. Thus it can be considered a useful technique for the surgical treatment of degenerative cervical disease. Georg Thieme Verlag KG Stuttgart · New York.

Stabilization and mobility of the head, neck and trunk in horses during overground locomotion: comparisons with humans and other primates

PubMed Central

Dunbar, Donald C.; Macpherson, Jane M.; Simmons, Roger W.; Zarcades, Athina

2009-01-01

SUMMARY Segmental kinematics were investigated in horses during overground locomotion and compared with published reports on humans and other primates to determine the impact of a large neck on rotational mobility (>20deg.) and stability (≤20deg.) of the head and trunk. Three adult horses (Equus caballus) performing walks, trots and canters were videotaped in lateral view. Data analysis included locomotor velocity, segmental positions, pitch and linear displacements and velocities, and head displacement frequencies. Equine, human and monkey skulls and cervical spines were measured to estimate eye and vestibular arc length during head pitch displacements. Horses stabilized all three segments in all planes during all three gaits, unlike monkeys and humans who make large head pitch and yaw rotations during walks, and monkeys that make large trunk pitch rotations during gallops. Equine head angular displacements and velocities, with some exceptions during walks, were smaller than in humans and other primates. Nevertheless, owing to greater off-axis distances, orbital and vestibular arc lengths remained larger in horses, with the exception of head–neck axial pitch during trots, in which equine arc lengths were smaller than in running humans. Unlike monkeys and humans, equine head peak-frequency ranges fell within the estimated range in which inertia has a compensatory stabilizing effect. This inertial effect was typically over-ridden, however, by muscular or ligamentous intervention. Thus, equine head pitch was not consistently compensatory, as reported in humans. The equine neck isolated the head from the trunk enabling both segments to provide a spatial reference frame. PMID:19043061

Stabilization and mobility of the head, neck and trunk in horses during overground locomotion: comparisons with humans and other primates.

PubMed

Dunbar, Donald C; Macpherson, Jane M; Simmons, Roger W; Zarcades, Athina

2008-12-01

Segmental kinematics were investigated in horses during overground locomotion and compared with published reports on humans and other primates to determine the impact of a large neck on rotational mobility (> 20 deg.) and stability (< or = 20 deg.) of the head and trunk. Three adult horses (Equus caballus) performing walks, trots and canters were videotaped in lateral view. Data analysis included locomotor velocity, segmental positions, pitch and linear displacements and velocities, and head displacement frequencies. Equine, human and monkey skulls and cervical spines were measured to estimate eye and vestibular arc length during head pitch displacements. Horses stabilized all three segments in all planes during all three gaits, unlike monkeys and humans who make large head pitch and yaw rotations during walks, and monkeys that make large trunk pitch rotations during gallops. Equine head angular displacements and velocities, with some exceptions during walks, were smaller than in humans and other primates. Nevertheless, owing to greater off-axis distances, orbital and vestibular arc lengths remained larger in horses, with the exception of head-neck axial pitch during trots, in which equine arc lengths were smaller than in running humans. Unlike monkeys and humans, equine head peak-frequency ranges fell within the estimated range in which inertia has a compensatory stabilizing effect. This inertial effect was typically over-ridden, however, by muscular or ligamentous intervention. Thus, equine head pitch was not consistently compensatory, as reported in humans. The equine neck isolated the head from the trunk enabling both segments to provide a spatial reference frame.

A randomized controlled trial investigating the effects of craniosacral therapy on pain and heart rate variability in fibromyalgia patients.

PubMed

Castro-Sánchez, Adelaida María; Matarán-Peñarrocha, Guillermo A; Sánchez-Labraca, Nuria; Quesada-Rubio, José Manuel; Granero-Molina, José; Moreno-Lorenzo, Carmen

2011-01-01

Fibromyalgia is a prevalent musculoskeletal disorder associated with widespread mechanical tenderness, fatigue, non-refreshing sleep, depressed mood and pervasive dysfunction of the autonomic nervous system: tachycardia, postural intolerance, Raynaud's phenomenon and diarrhoea. To determine the effects of craniosacral therapy on sensitive tender points and heart rate variability in patients with fibromyalgia. A randomized controlled trial. Ninety-two patients with fibromyalgia were randomly assigned to an intervention group or placebo group. Patients received treatments for 20 weeks. The intervention group underwent a craniosacral therapy protocol and the placebo group received sham treatment with disconnected magnetotherapy equipment. Pain intensity levels were determined by evaluating tender points, and heart rate variability was recorded by 24-hour Holter monitoring. After 20 weeks of treatment, the intervention group showed significant reduction in pain at 13 of the 18 tender points (P < 0.05). Significant differences in temporal standard deviation of RR segments, root mean square deviation of temporal standard deviation of RR segments and clinical global impression of improvement versus baseline values were observed in the intervention group but not in the placebo group. At two months and one year post therapy, the intervention group showed significant differences versus baseline in tender points at left occiput, left-side lower cervical, left epicondyle and left greater trochanter and significant differences in temporal standard deviation of RR segments, root mean square deviation of temporal standard deviation of RR segments and clinical global impression of improvement. Craniosacral therapy improved medium-term pain symptoms in patients with fibromyalgia.

First evidence of Hadrosauropodus in Gondwana (Yacoraite Formation, Maastrichtian-Danian), northwestern Argentina

NASA Astrophysics Data System (ADS)

Díaz-Martínez, Ignacio; de Valais, Silvina; Cónsole-Gonella, Carlos

2016-10-01

Uppermost Cretaceous (Campanian-Maastrichtian) large ornithopod tracks are scarce in Gondwana. This record is limited to few citations in the northern Argentina, Peru and possibly Bolivia, although their ichnological affinities are still under discussion. Recently, a new vertebrate tracksite with large ornithopod tracks has been found in the Maimará locality, Jujuy province, Argentina, from the Yacoraite Formation (Maastrichtian-Danian). The best preserved track is characterized by having large and bilobed heel impression and wide and short digit impressions with blunt claw marks. This record represents the unambiguous record of large ornithopod tracks in Gondwana in the Uppermost Cretaceous, and its features allow classifying it as Hadrosauropodus. Previously, this ichnotaxon had exclusively Laurasian distribution. Therefore, this record is the first evidence of Hadrosauropodus from Gondwana expanding the geographic range of this ichnogenus. A member of Hadrosauridae is reinforced as possible trackmaker of the Hadrosauropodus tracks. Uppermost Cretaceous hadrosaurid dinosaurs are scarce in Gondwana, being the record limited to Patagonia, La Pampa province and Antarctica. Therefore, the Maimará tracks increase the knowledge of this kind of dinosaur from Gondwana.

Long-Term Arctic Peatland Dynamics, Vegetation and Climate History of the Pur-Taz Region, Western Siberia

NASA Technical Reports Server (NTRS)

Peteet, Dorothy; Andreev, Andrei; Bardeen, William; Mistretta, Francesca

1998-01-01

Stratigraphic analyses of peat composition, LOI, pollen, spores, macrofossils, charcoal, and AMS ages are used to reconstruct the peatland, vegetation and climatic dynamics in the Pur-Taz region of western Siberia over 5000 years (9300 - 4500 BP). Section stratigraphy shows many changes from shallow lake sediment to different combinations of forested or open sedge, moss, and Equisetum fen and peatland environments. Macrofossil and pollen data indicate that Larix sibirica and Betula pubescens trees were first to arrive, followed by Picea obovata. The dominance of Picea macrofossils 6000-5000 BP in the Pur-Taz peatland along with regional Picea pollen maxima indicate warmer conditions and movement of the spruce treeline northward at this time. The decline of pollen and macrofossils from all of these tree species in uppermost peats suggests a change in the environment less favorable for their growth, perhaps cooler temperatures and/or less moisture. Of major significance is the evidence for old ages of the uppermost peats in this area of Siberia, suggesting a real lack of peat accumulation in recent millennia or recent oxidation of uppermost peat.

High-resolution 3D seismic model of the crustal and uppermost mantle structure in Poland

NASA Astrophysics Data System (ADS)

Grad, Marek; Polkowski, Marcin; Ostaficzuk, Stanisław R.

2016-01-01

In the area of Poland a contact between the Precambrian and Phanerozoic Europe and the Carpathians has a complicated structure and a complex P-wave velocity of the sedimentary cover, crystalline crust, Moho depth and the uppermost mantle. The geometry of the uppermost several kilometers of sediments is relatively well recognized from over 100,000 boreholes. The vertical seismic profiling (VSP) from 1188 boreholes provided detailed velocity data for regional tectonic units and for stratigraphic successions from Permian to the Tertiary and Quaternary deposits. These data, however, do not provide information about the velocity and basement depth in the central part of the Trans-European suture zone (TESZ) and in the Carpathians. So, the data set is supplemented by 2D velocity models from 32 deep seismic sounding refraction profiles which also provide information about the crust and uppermost mantle. Together with the results of other methods: vertical seismic profiling, magnetotelluric, allow for the creation of a detailed, high-resolution 3D model for the entire Earth's crust and the uppermost mantle down to a depth of 60 km. The thinnest sedimentary cover in the Mazury-Belarus anteclise is only 0.3 to 1 km thick, which increases to 7 to 8 km along the East European Craton (EEC) margin, and 9 to 12 km in the TESZ. The Variscan domain is characterized by a 1-4 km thick sedimentary cover, while the Carpathians are characterized by very thick sedimentary layers, up to about 20 km. The crystalline crust is differentiated and has a layered structure. The crust beneath the West European Platform (WEP; Variscan domain) is characterized by P-wave velocities of 5.8-6.6 km/s. The upper and middle crusts beneath the EEC are characterized by velocities of 6.1-6.6 km/s, and are underlain by a high velocity lower crust with a velocity of about 7 km/s. A general decrease in velocity is observed from the older to the younger tectonic domains. The TESZ is associated with a steep dip in the Moho depth, from 30-35 km in the Paleozoic Platform to 42-52 km in the Precambrian craton. The new model confirms the Moho depth derived from previous compilations. In the TESZ the lower crust has a very high seismic velocity (> 7.0 km/s) which correlates to the high P-wave velocity (about 8.4 km/s) in the uppermost mantle beneath the Polish Basin. The Cratonic area is generally characterized by high P-wave velocities (> 8.2 km/s), while the Phanerozoic area is characterized by velocities of ~ 8.0 km/s. In the TESZ very high velocities of 8.3-8.4 km/s are observed, and the southwestern limitation of this area coincides with a high velocity lower crust, and could be continued to the NW toward the Elbe line. The influence of the structure for teleseismic tomography time residuals of seismic waves traveling through the 3D seismic model was analyzed. Lithological candidates for the crust and uppermost mantle of the EEC and WEP were suggested by comparison to laboratory data. The presented 3D seismic model may make more reliable studies on global dynamics, and geotectonic correlations, particularly for sedimentary basins in the Polish Lowlands, the napped flysch sediment series in the Carpathians, the basement shape, the southwestern edge of the EEC, a high-velocity lower crust and the high-velocity uppermost mantle in the TESZ. Finally, the new 3D velocity model of the crust shows a heterogeneous structure and offers a starting point for the numerical modeling of deeper structures by allowing for a correction of the crustal effects in studies of the mantle heterogeneities.

Factors Affecting Volume Changes of the Somatosensory Cortex in Patients with Spinal Cord Injury: To Be Considered for Future Neuroprosthetic Design.

PubMed

Höller, Yvonne; Tadzic, Arijan; Thomschewski, Aljoscha C; Höller, Peter; Leis, Stefan; Tomasi, Santino Ottavio; Hofer, Christoph; Bathke, Arne; Nardone, Raffaele; Trinka, Eugen

2017-01-01

Spinal cord injury (SCI) leads to severe chronic disability, but also to secondary adaptive changes upstream to the injury in the brain which are most likely induced due to the lack of afferent information. These neuroplastic changes are a potential target for innovative therapies such as neuroprostheses, e.g., by stimulation in order to evoke sensation or in order to suppress phantom limb pain. Diverging results on gray matter atrophy have been reported in patients with SCI. Detectability of atrophy seems to depend on the selection of the regions of interest, while whole-brain approaches are not sensitive enough. In this study, we discussed previous research approaches and analyzed differential atrophic changes in incomplete SCI using manual segmentation of the somatosensory cortex. Patients with incomplete SCI (ASIA C-D), with cervical (N = 5) and thoracic (N = 6) injury were included. Time since injury was ≤12 months in 7 patients, and 144, 152, 216, and 312 months in the other patients. Age at the injury was ≤26 years in 4 patients and ≥50 years in 7 patients. A sample of 12 healthy controls was included in the study. In contrast to all previous studies that used voxel-based morphometry, we performed manual segmentation of the somatosensory cortex in the postcentral gyrus from structural magnetic resonance images and normalized the calculated volumes against the sum of volumes of an automated whole-head segmentation. Volumes were smaller in patients than in controls ( p  = 0.011), and as a tendency, female patients had smaller volumes than male patients ( p  = 0.017, uncorrected). No effects of duration (subacute vs. chronic), level of lesion (cervical vs. thoracic), region (left vs. right S1), and age at onset (≤26 vs. ≥50 years) was found. Our results demonstrate volume loss of S1 in incomplete SCI and encourage further research with larger sample sizes on volumetric changes in the acute and chronic stage of SCI, in order to document the moderating effect of type and location of injury on neuroplastic changes. A better understanding of neuroplastic changes in the sensorimotor cortex after SCI and its interaction with sex is needed in order to develop efficient rehabilitative interventions and neuroprosthetic technologies.

MRI and PET Imaging in Predicting Treatment Response in Patients With Stage IB-IVA Cervical Cancer

ClinicalTrials.gov

2018-06-18

Cervical Adenocarcinoma; Cervical Adenosquamous Carcinoma; Cervical Squamous Cell Carcinoma, Not Otherwise Specified; Cervical Undifferentiated Carcinoma; Recurrent Cervical Carcinoma; Stage IB2 Cervical Cancer; Stage II Cervical Cancer; Stage IIA Cervical Cancer; Stage IIB Cervical Cancer; Stage III Cervical Cancer; Stage IIIA Cervical Cancer; Stage IIIB Cervical Cancer; Stage IVA Cervical Cancer

Spinal cord projections of the rat main forelimb nerves, studied by transganglionic transport of WGA-HRP and by the disappearance of acid phosphatase.

PubMed

Castro-Lopes, J M; Coimbra, A

1991-03-01

The spinal cord projections of the 3 main forelimb nerves-median, radial and ulnar, were studied in the rat dorsal horn with transganglionic transport of wheat germ agglutinin-horseradish peroxidase (WGA-HRP), or using the disappearance of fluoride resistant acid phosphatase (FRAP) after nerve section. The projection patterns in lamina II were similar following the two procedures. The median and the radial nerve fibers projected to the medial and the intermediate thirds, respectively, of the dorsal horn lamina II in spinal cord segments C4-C8. The ulnar nerve projected to segments C6-C8 between the areas occupied by the other two nerves. The FRAP method also showed that the lateral part of lamina II, which was not filled by radial nerve fibers, received the projections from the dorsal cutaneous branches of cervical spinal nerves. In addition, FRAP disappeared from the medial end of segment T1 after skin incisions extending from the medial brachium to the axilla, which seemed due to severance of the cutaneous branchlets of the lateral anterior thoracic nerve. The FRAP procedure is thus sensitive enough to detect fibers in lamina II arising from small peripheral nerves, and may be used as an alternative to the anterograde tracing methods whenever there are no overlapping projections.

Cervical Hemilaminoplasty with Miniplates in Long Segment Intradural Extramedullary Ependymoma: Case Report and Technical Note.

PubMed

Oral, Sukru; Tumturk, Abdulfettah; Kucuk, Ahmet; Menku, Ahmet

2018-01-01

The surgical approaches for spinal tumors, to a great extent, have been developed in accordance with the developments in medical technology. Today, many surgical techniques are implemented as anterior, anterolateral, posterior, posterolateral and combined approaches. Due to its low morbidity, the posterior approach is the more preferred one. Laminectomy is a widely used technique, especially in neoplastic lesions. However, following laminectomy, there are numerous complications such as instability, kyphotic deformity and scar formation. In this paper, the excision of a tumor that was located intradural-extramedullary at the C3-C7 level with the cervical hemilaminoplasty technique is described. A 47-year-old female patient presented to our clinic with increasing complaints of neck and left arm pain, left arm numbness and searing pain for the last 10 years. On examination, hypoesthesia at the C4-7 dermatomes in the left upper extremity, an increase in deep tendon reflexes, and bilateral positive Hoffmann reflexes were observed. C3-C7 laminae were opened unilaterally on the right side with a midline skin incision. The laminae were drilled with a high-speed drill to provide a wide opening, both on the midline obliquely and from the border of the lamina-facet joint. After the tumor was totally excised, hemilaminae were placed into the previous position and reconstructed with mini-plates and screws. Cervical hemilaminoplasty provides a wide field of vision in tumor surgery of this region. Besides, the reconstruction of hemilaminae is important for stability. As the integrity of the spinal canal is preserved during reoperations of this region, the risk of complications is decreased.

Dexmedetomidine for an awake fiber-optic intubation of a parturient with Klippel-Feil syndrome, Type I Arnold Chiari malformation and status post released tethered spinal cord presenting for repeat cesarean section

PubMed Central

Shah, Tanmay H.; Badve, Manasi S.; Olajide, Kowe O.; Skorupan, Havyn M.; Waters, Jonathan H.; Vallejo, Manuel C.

2011-01-01

Patients with Klippel-Feil Syndrome (KFS) have congenital fusion of their cervical vertebrae due to a failure in the normal segmentation of the cervical vertebrae during the early weeks of gestation and also have myriad of other associated anomalies. Because of limited neck mobility, airway management in these patients can be a challenge for the anesthesiologist. We describe a unique case in which a dexmedetomidine infusion was used as sedation for an awake fiber-optic intubation in a parturient with Klippel-Feil Syndrome, who presented for elective cesarean delivery. A 36-year-old female, G2P1A0 with KFS (fusion of cervical vertebrae) who had prior cesarean section for breech presentation with difficult airway management was scheduled for repeat cesarean delivery. After obtaining an informed consent, patient was taken in the operating room and non-invasive monitors were applied. Dexmedetomidine infusion was started and after adequate sedation, an awake fiber-optic intubation was performed. General anesthetic was administered after intubation and dexmedetomidine infusion was continued on maintenance dose until extubation. Klippel-Feil Syndrome (KFS) is a rare congenital disorder for which the true incidence is unknown, which makes it even rare to see a parturient with this disease. Patients with KFS usually have other congenital abnormalities as well, sometimes including the whole thoraco-lumbar spine (Type III) precluding the use of neuraxial anesthesia for these patients. Obstetric patients with KFS can present unique challenges in administering anesthesia and analgesia, primarily as it relates to the airway and dexmedetomidine infusion has shown promising result to manage the airway through awake fiberoptic intubation without any adverse effects on mother and fetus. PMID:24765318

Use of a Zero-Profile Device for Contiguous 2-Level Anterior Cervical Diskectomy and Fusion: Comparison with Cage with Plate Construct.

PubMed

Yun, Dong-Ju; Lee, Sang-Jin; Park, Sang-Joon; Oh, Hyeong Seok; Lee, Young Jae; Oh, Hyun Min; Lee, Sang-Ho

2017-01-01

A new zero-profile, standalone device (Zero P) was recently developed and has shown a lower incidence rate of complications and competitive clinical outcomes compared with anterior cervical cage with plate construct (CP) in single and multilevel anterior cervical diskectomy and fusion (ACDF). However, there is still concern whether Zero P is appropriate for multilevel ACDF. In addition, there have been few reports of contiguous 2-level ACDF used in conjunction with Zero P. We reviewed contiguous 2-level ACDF performed from December 2006 to February 2015. A total of 63 patients met inclusion criteria for the study (CP group = 32 cases; Zero P group = 31 cases). All preoperative and postoperative clinical and radiologic parameters were recorded. These parameters were compared between both groups. The postoperative change of Cobb S over time in the Zero P group was significantly different from that in the CP group. The maintenance of Cobb S in the Zero P group was better than that in the CP group (P < 0.05). The maintenance of anterior intervertebral disk height (IDH) at postoperative assessment for the Zero P group was significantly better than that in the CP group (P < 0.05). Within-group comparison of the postoperative change of anterior and posterior IDH over time revealed that the anterior IDH was significantly lower than the posterior IDH in the Zero P group (P < 0.05). For 2-level contiguous ACDF, the use of a zero-profile device has the capacity to show compatible outcomes in correction and maintenance of segmental angle if the anterior titanium alloy plate is properly positioned at the anterior vertebral line. Copyright © 2016 Elsevier Inc. All rights reserved.

Adjacent-segment disease after thoracic pedicle screw fixation.

PubMed

Agarwal, Nitin; Heary, Robert F; Agarwal, Prateek

2018-03-01

OBJECTIVE Pedicle screw fixation is a technique widely used to treat conditions ranging from spine deformity to fracture stabilization. Pedicle screws have been used traditionally in the lumbar spine; however, they are now being used with increasing frequency in the thoracic spine as a more favorable alternative to hooks, wires, or cables. Although safety concerns, such as the incidence of adjacent-segment disease (ASD) after cervical and lumbar fusions, have been reported, such issues in the thoracic spine have yet to be addressed thoroughly. Here, the authors review the literature on ASD after thoracic pedicle screw fixation and report their own experience specifically involving the use of pedicle screws in the thoracic spine. METHODS Select references from online databases, such as PubMed (provided by the US National Library of Medicine at the National Institutes of Health), were used to survey the literature concerning ASD after thoracic pedicle screw fixation. To include the authors' experience at Rutgers New Jersey Medical School, a retrospective review of a prospectively maintained database was performed to determine the incidence of complications over a 13-year period in 123 consecutive adult patients who underwent thoracic pedicle screw fixation. Children, pregnant or lactating women, and prisoners were excluded from the review. By comparing preoperative and postoperative radiographic images, the occurrence of thoracic ASD and disease within the surgical construct was determined. RESULTS Definitive radiographic fusion was detected in 115 (93.5%) patients. Seven incidences of instrumentation failure and 8 lucencies surrounding the screws were observed. One patient was observed to have ASD of the thoracic spine. The mean follow-up duration was 50 months. CONCLUSIONS This long-term radiographic evaluation revealed the use of pedicle screws for thoracic fixation to be an effective stabilization modality. In particular, ASD seems to be less of a problem in the relatively immobile thoracic spine than in the more mobile cervical and lumbar spines.

Subpial Adeno-associated Virus 9 (AAV9) Vector Delivery in Adult Mice.

PubMed

Tadokoro, Takahiro; Miyanohara, Atsushi; Navarro, Michael; Kamizato, Kota; Juhas, Stefan; Juhasova, Jana; Marsala, Silvia; Platoshyn, Oleksandr; Curtis, Erik; Gabel, Brandon; Ciacci, Joseph; Lukacova, Nada; Bimbova, Katarina; Marsala, Martin

2017-07-13

The successful development of a subpial adeno-associated virus 9 (AAV9) vector delivery technique in adult rats and pigs has been reported on previously. Using subpially-placed polyethylene catheters (PE-10 or PE-5) for AAV9 delivery, potent transgene expression through the spinal parenchyma (white and gray matter) in subpially-injected spinal segments has been demonstrated. Because of the wide range of transgenic mouse models of neurodegenerative diseases, there is a strong desire for the development of a potent central nervous system (CNS)-targeted vector delivery technique in adult mice. Accordingly, the present study describes the development of a spinal subpial vector delivery device and technique to permit safe and effective spinal AAV9 delivery in adult C57BL/6J mice. In spinally immobilized and anesthetized mice, the pia mater (cervical 1 and lumbar 1-2 spinal segmental level) was incised with a sharp 34 G needle using an XYZ manipulator. A second XYZ manipulator was then used to advance a blunt 36G needle into the lumbar and/or cervical subpial space. The AAV9 vector (3-5 µL; 1.2 x 10 13 genome copies (gc)) encoding green fluorescent protein (GFP) was then injected subpially. After injections, neurological function (motor and sensory) was assessed periodically, and animals were perfusion-fixed 14 days after AAV9 delivery with 4% paraformaldehyde. Analysis of horizontal or transverse spinal cord sections showed transgene expression throughout the entire spinal cord, in both gray and white matter. In addition, intense retrogradely-mediated GFP expression was seen in the descending motor axons and neurons in the motor cortex, nucleus ruber, and formatio reticularis. No neurological dysfunction was noted in any animals. These data show that the subpial vector delivery technique can successfully be used in adult mice, without causing procedure-related spinal cord injury, and is associated with highly potent transgene expression throughout the spinal neuraxis.

Anterior Cervical Discectomy and Fusion for Adjacent Segment Disease: Clinical Outcomes and Cost Utility of Surgical Intervention.

PubMed

O'Neill, Kevin R; Wilson, Robert J; Burns, Katharine M; Mioton, Lauren M; Wright, Brian T; Adogwa, Owoicho; McGirt, Matthew J; Devin, Clinton J

2016-07-01

Retrospective review. Determine clinical outcomes and cost utility of anterior cervical discectomy and fusion (ACDF) for the treatment of adjacent segment disease (ASD). The incidence of symptomatic ASD after ACDF has been estimated to occur in up to 26% of patients. Commonly, these patients will undergo an additional ACDF procedure. However, there are currently no studies available that adequately describe the clinical outcomes or cost utility of performing ACDF for ASD. A retrospective review of 40 patients undergoing ACDF for ASD was performed. Baseline and 2-year neck and arm pain (NRS-NP, NRS-AP), neck disability index (NDI), physical and mental quality of life (SF-12 PCS & MCS), and Zung depression score (ZDS) were assessed. Two-year total neck-related medical resource utilization, amount of missed work, and health-state values were determined. Quality-adjusted life years (QALYs) were calculated from EQ-5D assessments with US valuation. Comprehensive costs (indirect, direct, and total cost) and the value (cost-per-QALY gained) of performing ACDF for ASD were assessed. Performing ACDF to treat ASD resulted in significant improvements (P<0.05) in NRS-NP, NRS-AP, NDI, SF-12 PCS, and ZDS outcome measures. Patient-reported health states also significantly improved, with a mean cumulative 2-year gain of 0.54 QALYs. The mean 2-year cost of surgery was $32,616 (direct cost: $25,391; indirect cost: $7225). ACDF for the treatment of ASD was associated with a mean 2-year cost per QALY gained of $60,526. Performing ACDF for ASD resulted in significant improvements in patient pain, disability, and quality of life. Further, the mean 2-year cost-per-QALY was determined to be $60,526, which suggests surgical intervention to be cost effective. This study is the first to provide evidence that performing an ACDF for ASD is both clinically and cost effective.

FDG and FMISO PET Hypoxia Evaluation in Cervical Cancer

ClinicalTrials.gov

2016-12-28

Cervical Adenocarcinoma; Cervical Squamous Cell Carcinoma; Stage IB Cervical Cancer; Stage IIA Cervical Cancer; Stage IIB Cervical Cancer; Stage III Cervical Cancer; Stage IVA Cervical Cancer; Stage IVB Cervical Cancer

Cetuximab, Cisplatin, and Radiation Therapy in Treating Patients With Stage IB, Stage II, Stage III, or Stage IVA Cervical Cancer

ClinicalTrials.gov

2014-12-29

Cervical Adenocarcinoma; Cervical Adenosquamous Carcinoma; Cervical Small Cell Carcinoma; Cervical Squamous Cell Carcinoma; Stage IB Cervical Cancer; Stage IIA Cervical Cancer; Stage IIB Cervical Cancer; Stage III Cervical Cancer; Stage IVA Cervical Cancer

Cisplatin and Radiation Therapy Followed by Paclitaxel and Carboplatin in Treating Patients With Stage IB-IVA Cervical Cancer

ClinicalTrials.gov

2017-05-03

Cervical Adenocarcinoma; Cervical Adenosquamous Carcinoma; Cervical Squamous Cell Carcinoma, Not Otherwise Specified; Stage IB Cervical Cancer; Stage IIA Cervical Cancer; Stage IIB Cervical Cancer; Stage IIIA Cervical Cancer; Stage IIIB Cervical Cancer; Stage IVA Cervical Cancer

[Effect of electroacupuncture intervention on expression of extracellular matrix collagen and metabolic enzymes].

PubMed

Liao, Jun; Zhang, Le; Ke, Mei-gui; Xu, Teng

2013-12-01

To observe the effect of electroacupuncture (EA) at "Dazhui" (GV 14) on the contents of extracellular matrix (ECM), collagen type II (COL-II), collagen type V (COL-V), matrix metalloproteinase (MMP)-13, tissue inhibitor of metalloproteinase (TIMP)-1 in rats with cervicovertebral disc degeneration so as to explore its mechanism underlying relief of intervertebral disc degeneration. A total of 28 SD rats were randomly divided into sham group (n = 7), model group (n = 7), EA group (n = 7) and medication group (n = 7). The model of cervical intervertebral disc degeneration was established by trans-section of the deep neck splenius, the longest muscles of head, neck costocervicalis, head semi-spinatus muscle, supraspinous ligament and interspinal ligaments of cervical 2-7 segments, etc. to produce imbalance between the dynamic and static force. EA was applied to "Dazhui" (GV 14) for 30 min, once daily for 28 days, with a 2 days' interval between two courses. Animals of the medication group were treated by oral administration of meloxicam tablets (0.75 mg/kg) once daily for 28 days, with a 2 days' interval between two courses. Immunohistochemistry was used to measure the expression of ECM, COL- II, COL-V, MMP-13 and TIMP-1 in the cervicovertebral disc tissue. Compared with the sham group, the expression levels of ECM and COL-II proteins in the cervicovertebral disc tissue were significantly decreased in the model group (P < 0.01), while COL-V and MMP-13 expression levels in the model group were significantly increased (P < 0.01, P < 0.05). Compared with the model group, both ECM and COL-Il expression levels were considerably increased in the EA group and medication group (P < 0.01), while COL-V and MMP-13 expression levels were considerably down-regulated (P < 0.01, P < 0.05). No significant differences were found among the four groups in TIMP-1 expression levels (P > 0.05). EA of "Dazhui" (GV 14) can effectively regulate extracellular matrix system in rats with cervical intervertebral disc degeneration, which is possibly related to its effect in relieving cervical spondylosis.

Effect of electroacupuncture on thermal pain threshold and expression of calcitonin-gene related peptide, substance P and γ-aminobutyric acid in the cervical dorsal root ganglion of rats with incisional neck pain

PubMed Central

Qiao, Li-na; Liu, Jun-ling; Tan, Lian-hong; Yang, Hai-long; Zhai, Xu; Yang, Yong-sheng

2017-01-01

Objective Acupuncture therapy effectively reduces post-surgical pain, but its mechanism of action remains unclear. The aim of this study was to investigate whether expression of γ-aminobutyric acid (GABA) and the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) in the primary sensory neurons of cervical dorsal root ganglia (DRG) are involved in electroacupuncture (EA)-induced analgesia in a rat model of incisional neck pain. Methods The pain model was established by making a longitudinal midline neck incision in 60 rats. Another 15 rats underwent sham surgery (normal group). Post-incision, 15 rats remained untreated (model group) and 45 rats underwent EA (frequency 2/100 Hz, intensity 1 mA) at bilateral LI18, LI4-PC6 or ST36-GB34 (n=15 each) for 30 min at 4 hours, 24 hours, and 48 hours post-surgery, followed by thermal pain threshold (PT) measurement. 30 min later, the rats were euthanased and cervical (C3-6) DRGs removed for measurement of immunoreactivity and mRNA expression of SP/CGRP and the GABAergic neuronal marker glutamic acid decarboxylase 67 (GAD67). Results Thermal PT was significantly lower in the model group versus the normal group and increased in the LI18 and LI4-PC6 groups but not the ST36-GB34 group compared with the model group. Additionally, EA at LI18 and LI4-PC6 markedly suppressed neck incision-induced upregulation of mRNA/protein expression of SP/CGRP, and upregulated mRNA/protein expression of GAD67 in the DRGs of C3-6 segments. Conclusions EA at LI18/LI4-PC6 increases PT in rats with incisional neck pain, which is likely related to downregulation of pronociceptive mediators SP/CGRP and upregulation of the inhibitory transmitter GABA in the primary sensory neurons of cervical DRGs. PMID:28600329

SU-F-BRF-09: A Non-Rigid Point Matching Method for Accurate Bladder Dose Summation in Cervical Cancer HDR Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, H; Zhen, X; Zhou, L

2014-06-15

Purpose: To propose and validate a deformable point matching scheme for surface deformation to facilitate accurate bladder dose summation for fractionated HDR cervical cancer treatment. Method: A deformable point matching scheme based on the thin plate spline robust point matching (TPSRPM) algorithm is proposed for bladder surface registration. The surface of bladders segmented from fractional CT images is extracted and discretized with triangular surface mesh. Deformation between the two bladder surfaces are obtained by matching the two meshes' vertices via the TPS-RPM algorithm, and the deformation vector fields (DVFs) characteristic of this deformation is estimated by B-spline approximation. Numerically, themore » algorithm is quantitatively compared with the Demons algorithm using five clinical cervical cancer cases by several metrics: vertex-to-vertex distance (VVD), Hausdorff distance (HD), percent error (PE), and conformity index (CI). Experimentally, the algorithm is validated on a balloon phantom with 12 surface fiducial markers. The balloon is inflated with different amount of water, and the displacement of fiducial markers is benchmarked as ground truth to study TPS-RPM calculated DVFs' accuracy. Results: In numerical evaluation, the mean VVD is 3.7(±2.0) mm after Demons, and 1.3(±0.9) mm after TPS-RPM. The mean HD is 14.4 mm after Demons, and 5.3mm after TPS-RPM. The mean PE is 101.7% after Demons and decreases to 18.7% after TPS-RPM. The mean CI is 0.63 after Demons, and increases to 0.90 after TPS-RPM. In the phantom study, the mean Euclidean distance of the fiducials is 7.4±3.0mm and 4.2±1.8mm after Demons and TPS-RPM, respectively. Conclusions: The bladder wall deformation is more accurate using the feature-based TPS-RPM algorithm than the intensity-based Demons algorithm, indicating that TPS-RPM has the potential for accurate bladder dose deformation and dose summation for multi-fractional cervical HDR brachytherapy. This work is supported in part by the National Natural ScienceFoundation of China (no 30970866 and no 81301940)« less

Effect of electroacupuncture on thermal pain threshold and expression of calcitonin-gene related peptide, substance P and γ-aminobutyric acid in the cervical dorsal root ganglion of rats with incisional neck pain.

PubMed

Qiao, Li-Na; Liu, Jun-Ling; Tan, Lian-Hong; Yang, Hai-Long; Zhai, Xu; Yang, Yong-Sheng

2017-08-01

Acupuncture therapy effectively reduces post-surgical pain, but its mechanism of action remains unclear. The aim of this study was to investigate whether expression of γ-aminobutyric acid (GABA) and the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) in the primary sensory neurons of cervical dorsal root ganglia (DRG) are involved in electroacupuncture (EA)-induced analgesia in a rat model of incisional neck pain. The pain model was established by making a longitudinal midline neck incision in 60 rats. Another 15 rats underwent sham surgery (normal group). Post-incision, 15 rats remained untreated (model group) and 45 rats underwent EA (frequency 2/100 Hz, intensity 1 mA) at bilateral LI18, LI4-PC6 or ST36-GB34 (n=15 each) for 30 min at 4 hours, 24 hours, and 48 hours post-surgery, followed by thermal pain threshold (PT) measurement. 30 min later, the rats were euthanased and cervical (C3-6) DRGs removed for measurement of immunoreactivity and mRNA expression of SP/CGRP and the GABAergic neuronal marker glutamic acid decarboxylase 67 (GAD67). Thermal PT was significantly lower in the model group versus the normal group and increased in the LI18 and LI4-PC6 groups but not the ST36-GB34 group compared with the model group. Additionally, EA at LI18 and LI4-PC6 markedly suppressed neck incision-induced upregulation of mRNA/protein expression of SP/CGRP, and upregulated mRNA/protein expression of GAD67 in the DRGs of C3-6 segments. EA at LI18/LI4-PC6 increases PT in rats with incisional neck pain, which is likely related to downregulation of pronociceptive mediators SP/CGRP and upregulation of the inhibitory transmitter GABA in the primary sensory neurons of cervical DRGs. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

SU-F-T-423: Automating Treatment Planning for Cervical Cancer in Low- and Middle- Income Countries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kisling, K; Zhang, L; Yang, J

Purpose: To develop and test two independent algorithms that automatically create the photon treatment fields for a four-field box beam arrangement, a common treatment technique for cervical cancer in low- and middle-income countries. Methods: Two algorithms were developed and integrated into Eclipse using its Advanced Programming Interface:3D Method: We automatically segment bony anatomy on CT using an in-house multi-atlas contouring tool and project the structures into the beam’s-eye-view. We identify anatomical landmarks on the projections to define the field apertures. 2D Method: We generate DRRs for all four beams. An atlas of DRRs for six standard patients with corresponding fieldmore » apertures are deformably registered to the test patient DRRs. The set of deformed atlas apertures are fitted to an expected shape to define the final apertures. Both algorithms were tested on 39 patient CTs, and the resulting treatment fields were scored by a radiation oncologist. We also investigated the feasibility of using one algorithm as an independent check of the other algorithm. Results: 96% of the 3D-Method-generated fields and 79% of the 2D-method-generated fields were scored acceptable for treatment (“Per Protocol” or “Acceptable Variation”). The 3D Method generated more fields scored “Per Protocol” than the 2D Method (62% versus 17%). The 4% of the 3D-Method-generated fields that were scored “Unacceptable Deviation” were all due to an improper L5 vertebra contour resulting in an unacceptable superior jaw position. When these same patients were planned with the 2D method, the superior jaw was acceptable, suggesting that the 2D method can be used to independently check the 3D method. Conclusion: Our results show that our 3D Method is feasible for automatically generating cervical treatment fields. Furthermore, the 2D Method can serve as an automatic, independent check of the automatically-generated treatment fields. These algorithms will be implemented for fully automated cervical treatment planning.« less

Veliparib, Topotecan Hydrochloride, and Filgrastim or Pegfilgrastim in Treating Patients With Persistent or Recurrent Cervical Cancer

ClinicalTrials.gov

2017-06-15

Cervical Adenocarcinoma; Cervical Adenosquamous Carcinoma; Cervical Small Cell Carcinoma; Cervical Squamous Cell Carcinoma; Recurrent Cervical Carcinoma; Stage III Cervical Cancer; Stage IVA Cervical Cancer; Stage IVB Cervical Cancer

Cisplatin and Radiation Therapy With or Without Tirapazamine in Treating Patients With Cervical Cancer

ClinicalTrials.gov

2017-05-30

Cervical Adenocarcinoma; Cervical Adenosquamous Cell Carcinoma; Cervical Squamous Cell Carcinoma; Stage IB Cervical Cancer; Stage IIA Cervical Cancer; Stage IIB Cervical Cancer; Stage III Cervical Cancer; Stage IVA Cervical Cancer

Lateral mass screw-rod fixation of the cervical spine: a prospective clinical series with 1-year follow-up.

PubMed

Deen, H Gordon; Birch, Barry D; Wharen, Robert E; Reimer, Ronald

2003-01-01

Lateral mass plating has become the technique of choice for posterior cervical fixation. Although these systems are safe and reliable, they can be difficult to use in patients with abnormal cervical anatomy; screw placement can be compromised by the fixed hole spacing of the plate; screw back-out and other forms of implant failure can occur; and extension across the cervicothoracic junction can be problematic. To report a series of patients undergoing posterior cervical stabilization with a polyaxial screw-rod construct and to investigate whether this new system offers any advantages over existing methods of fixation. A prospective study evaluating clinical and radiographic parameters in a consecutive series of patients treated with this technique. There were 21 patients in the study group. The surgical indication was cervical spondylosis in 14, trauma in 2, postsurgical kyphosis in 2 and 1 case each of congenital cervicothoracic stenosis, C7-T1 pseudarthrosis and basilar invagination with brainstem compression. Clinical indicators included age, gender, neurologic status, surgical indication and number of levels stabilized. Note was made of whether laminectomy and concomitant anterior reconstructive surgery were performed. Radiographic indicators included early postoperative computed tomography (CT) scan to check for screw placement and plain radiographs at subsequent visits. The participants in this study underwent posterior cervical stabilization using lateral mass screw-rod fixation. Clinical and radiographic assessment was carried out immediately after surgery, and 3, 6 and 12 months after surgery. One-year follow-up was obtained in all cases. A total of 212 screws were implanted in 21 patients. Fixation was carried out over an average of 5.5 spinal segments (range, 2 to 11). The system was successfully implanted in all patients despite the presence of coronal and sagittal plane deformities and/or lateral mass abnormalities in the majority of cases. This system allowed for screw placement in the occiput, C1 lateral mass, C2 pars, C3-C7 lateral masses and upper thoracic pedicles. Early postoperative CT scanning confirmed satisfactory screw placement in all cases. Three patients experienced transient single-level radiculopathy, for an incidence of 1.4% per screw placed. Two patients developed wound seromas requiring evacuation. There were no infections or other wound healing problems. There were no examples of cord or vertebral artery injury, cerebrospinal fluid leak, screw malposition or back-out, loss of alignment or implant failure. When compared with plating techniques, screw-rod fixation appeared to offer several advantages. First, unlike plates, rods proved to be amenable to multiplanar contouring, which is often needed for deformities associated with cervical spondylosis. Second, lateral mass screw placement was more precise because it was not constrained by the hole spacing of the plate. Third, screw back-out and other types of implant failure were not seen. Fourth, the screw-rod system was more easily extended to the occiput and across the cervicothoracic junction. Fifth, the screw-rod system permitted the application of compression, distraction and reduction forces within the construct, to a greater extent than plate systems. The incidence of postoperative radiculopathy was similar to that seen with plate systems. These data indicate that posterior cervical stabilization with polyaxial screw-rod fixation is a safe, straightforward technique that appears to offer some advantages over existing methods of fixation. Results appear to be durable at 1-year follow-up. Benefits are more significant with longer constructs, especially those extending to the occiput or crossing the cervicothoracic junction.

Colorimetric stack pad immunoassay for bacterial identification.

PubMed

Eltzov, Evgeni; Marks, Robert S

2017-01-15

A new colorimetric immunoassay concept, utilizing conventional lateral flow membranes (e.g., conjugation, sample, absorption and nitrocellulose), were placed in a different configuration in a stacking manner, where the liquid sample that may contain the analyte diffuses from the bottom to the upper-most layer. The key element of this proprietary technology is a capture layer, where a nitrocellulose membrane is modified with the target analyte of interest, namely in this study target Escherichia coli. During the immunoassay operation, samples contaminated with the target bacteria will conjugate to their corresponding HRP-antibodies laying in wait and the immune-target measurand complex flows by capillarity towards the upper-most layer to generate a colorimetric signal (positive answer) through an enzymatic reaction. In target-free samples, previously immobilized target bacteria on the capture layer will prevent the HRP-labeled anti-target antibodies from migrating to the upper-most layer, where the enzymatic substrate lays in wait. After optimization, the sensitivity of this approach was found to be 1,000 folds higher than ELISAs (10 2 cellsmL -1 ). The advantages of the stacked pad assay include: miniaturization, operational simplicity, fast response time (less than 5min), useful sensitivity. Copyright © 2016 Elsevier B.V. All rights reserved.

Seismic Structure of India from Regional Waveform Matching

NASA Astrophysics Data System (ADS)

Gaur, V.; Maggi, A.; Priestley, K.; Rai, S.

2003-12-01

We use a neighborhood adaptive grid search procedure and reflectivity synthetics to model regional distance range (500-2000~km) seismograms recorded in India and to determine the variation in the crust and uppermost mantle structure across the subcontinent. The portions of the regional waveform which are most influenced by the crust and uppermost mantle structure are the 10-100~s period Pnl and fundamental mode surface waves. We use the adaptive grid search algorithm to match both portions of the seismogram simultaneously. This procedure results in a family of 1-D path average crust and upper mantle velocity and attenuation models whose propagation characteristics closely match those of the real Earth. Our data set currently consist of ˜20 seismograms whose propagation paths are primarily confined to the Ganges Basin in north India and the East Dharwar Craton of south India. The East Dharwar Craton has a simple and uniform structure consisting of a 36+/-2 km thick two layer crust, and an uppermost mantle with a sub-Moho velocity of 4.5~km/s. The structure of northern India is more complicated, with pronounced low velocities in the upper crustal layer due to the large sediment thicknesses in the Ganges basin.

Uppermost Mantle Deformation and Hydration Beneath the Gorda Plate Inferred from Pn Travel-times

NASA Astrophysics Data System (ADS)

VanderBeek, B. P.; Toomey, D. R.

2017-12-01

Deformation of the uppermost oceanic mantle is thought to occur primarily in response to divergence beneath mid-ocean ridges with little subsequent deformation off-axis. A notable exception to this is the Gorda plate where sinuous magnetic anomalies and numerous intra-plate earthquakes indicate diffuse, plate-wide deformation. Thus, the Gorda region provides a natural laboratory to investigate the non-rigid behavior of tectonic plates. We invert Pn (the seismic head wave refracted below the Moho) arrival times from 770 local earthquakes for epicentral and mantle anisotropic velocity parameters to understand how the surficial pattern of deformation translates into the uppermost 10 km of the mantle. Specifically, we ask does the pattern of seismic anisotropy reflect spreading-induced fabrics or has it been re-worked by extensive deformation of the Gorda plate? If it has been re-worked, does it reflect pervasive faulting of the uppermost mantle or plate-scale ductile deformation? And, are isotropic velocities anomalously slow suggesting significant mantle hydration? Preliminary results show that the average mantle velocity beneath Gorda is 7.55 km/s. Velocities vary azimuthally by 4% and the fast-propagation direction is sub-parallel to Pacific absolute plate motion (APM). In comparison, the uppermost mantle beneath the Juan de Fuca (JdF) plate is characterized by 4.6% anisotropy with a mean velocity of 7.85 km/s [VanderBeek and Toomey, 2017]; the fast propagation direction trends between the paleo-spreading direction and JdF APM. The reduced Gorda velocities may indicate a greater extent of fault-controlled hydration of the shallow mantle compared to the JdF plate. In both regions, the anisotropic structure argues against the notion that shallow mantle deformation ceases away from the ridge. Instead, shearing across Gorda due to differential motion between the Pacific and JdF plates [e.g. Bodmer et al., 2015] may cause broad scale ductile deformation and the realignment of shallow mantle fabrics. Beneath the JdF plate, the anisotropic signal is inferred to track the evolution of mantle flow as it evolves from divergence at the ridge to simple shear that is more closely aligned with APM. We discuss the rheologic implications of these observations and the patterns of mantle flow and deformation in Cascadia.

Glycoprotein and Glycan in Tissue and Blood Samples of Patients With Stage IB-IVA Cervical Cancer Undergoing Surgery to Remove Pelvic and Abdominal Lymph Nodes

ClinicalTrials.gov

2017-08-23

Cervical Adenocarcinoma; Cervical Adenosquamous Carcinoma; Cervical Small Cell Carcinoma; Cervical Squamous Cell Carcinoma, Not Otherwise Specified; Stage IB Cervical Cancer; Stage IIA Cervical Cancer; Stage IIB Cervical Cancer; Stage III Cervical Cancer; Stage IVA Cervical Cancer

Acute inflammation induces segmental, bilateral, supraspinally mediated opioid release in the rat spinal cord, as measured by μ-opioid receptor internalization

PubMed Central

Chen, Wenling; Marvizón, Juan Carlos G.

2009-01-01

The objective of this study was to measure opioid release in the spinal cord during acute and long-term inflammation using μ-opioid receptor (MOR) internalization. In particular, we determined whether opioid release occurs in the segments receiving the noxious signals or in the entire spinal cord, and whether it involves supraspinal signals. Internalization of neurokinin 1 receptors (NK1Rs) was measured to track the intensity of the noxious stimulus. Rats received peptidase inhibitors intrathecally to protect opioids from degradation. Acute inflammation of the hindpaw with formalin induced moderate MOR internalization in the L5 segment bilaterally, whereas NK1R internalization occurred only ipsilaterally. MOR internalization was restricted to the lumbar spinal cord, regardless of whether the peptidase inhibitors were injected in a lumbar or thoracic site. Formalin-induced MOR internalization was substantially reduced by isoflurane anesthesia. It was also markedly reduced by a lidocaine block of the cervical-thoracic spinal cord (which did not affect the evoked NK1R internalization) indicating that spinal opioid release is mediated supraspinally. In the absence of peptidase inhibitors, formalin and hindpaw clamp induced a small amount of MOR internalization, which was significantly higher than in controls. To study spinal opioid release during chronic inflammation, we injected Complete Freund's Adjuvant (CFA) in the hindpaw and peptidase inhibitors intrathecally. Two days later, no MOR or NK1R internalization was detected. Furthermore, CFA inflammation decreased MOR internalization induced by clamping the inflamed hindpaw. These results show that acute inflammation, but not chronic inflammation, induce segmental opioid release in the spinal cord that involves supraspinal signals. PMID:19298846