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Sample records for sagittal coronal planes

  1. Evaluation of uterine peristalsis using cine MRI on the coronal plane in comparison with the sagittal plane.

    PubMed

    Shitano, Fuki; Kido, Aki; Kataoka, Masako; Fujimoto, Koji; Kiguchi, Kayo; Fushimi, Yasutaka; Togashi, Kaori

    2016-01-01

    Uterine peristalsis is supposed to be closely related to the early stages of reproduction. Sperms are preferentially transported from the uterine cervix to the side of the tube with the dominant follicle. However, with respect to magnetic resonance imaging (MRI), uterine peristalsis has only been evaluated at the sagittal plane of cine MRI. To evaluate and compare uterine peristalsis both on sagittal and coronal planes using cine MRI. Internal ethics committee approval was obtained, and subjects provided informed written consent. Thirty-one women underwent MRI scans in the periovulatory phase of the menstrual cycle. Cine MR images obtained by fast advanced spin echo sequence at 3-T field strength magnet (Toshiba Medical Systems) were visually evaluated by two independent radiologists. The frequency and the direction of peristalsis, and the presence of outer myometrium conduction of signal intensities (OMC), were evaluated. The laterality of the dominant follicle was determined on axial images and compared with the peristaltic direction in fundus. The subjects in which peristaltic directions were more clearly recognized were significantly frequent in coronal planes than in sagittal planes (P < 0.05). There was no significant difference in the peristaltic frequency between the sagittal and the coronal plane. However, the OMC was more recognized in the coronal plane than in the sagittal plane (P < 0.05). Peristaltic waves conducted toward the possible ovulation side were observed in only three of the 10 subjects. OMC of uterine peristalsis was better demonstrated in the coronal plane compared to the sagittal plane. © The Foundation Acta Radiologica 2015.

  2. Coronal plane trunk asymmetry is associated with whole-body sagittal alignment in healthy young adolescents before pubertal peak growth.

    PubMed

    Dolphens, Mieke; Vleeming, Andry; Castelein, René; Vanderstraeten, Guy; Schlösser, Tom; Plasschaert, Frank; Danneels, Lieven

    2017-06-03

    To investigate coronal plane trunk asymmetry (TA) and its association with sagittal postural alignment in healthy subjects before pubertal peak growth. In this cross-sectional baseline study, 1190 healthy pre-peak growth velocity subjects were included. Coronal plane TA was evaluated using back surface topography. Whole-body sagittal alignment (previously validated and objectively classified as neutral, sway-back or leaning-forward) and sagittal spinopelvic profile (trunk lean, lumbar lordosis, thoracic kyphosis, sacral inclination and length of the posteriorly inclined thoracolumbar segment) were determined, as were height, proportion of trunk to body length, body mass index, generalized joint laxity, and handedness. Logistic regression analysis yielded overall sagittal posture class to be independently associated with coronal plane TA: having a leaning-forward posture associated with a nearly three times higher odds of coronal TA (p < 0.001) compared to neutrals. A sway-back was 2.2 times more likely to show TA (p = 0.016) than a neutral, yet only in boys. Significant associations with coronal TA were also found for trunk lean, thoracic kyphosis and body mass index. These correlations, however, were gender and posture class specific. The spinal region where asymmetry is seen, varies according to the whole-body sagittal alignment type: primary thoracic curves were the most frequent in leaning-forwards, whereas primary curves in the lumbar or declive thoracolumbar segment were the most common in sway-backs. In immature spines without known scoliosis, coronal plane TA is associated with whole-body sagittal alignment. It is more often seen in non-neutral than neutral sagittal posture types. Whether adolescent idiopathic scoliosis is related with postural characteristics before pubertal growth peak, should be addressed in future prospective studies.

  3. Fixed Sagittal Plane Imbalance

    PubMed Central

    Savage, Jason W.; Patel, Alpesh A.

    2014-01-01

    Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction. PMID:25396111

  4. Fixed sagittal plane imbalance.

    PubMed

    Savage, Jason W; Patel, Alpesh A

    2014-12-01

    Study Design Literature review. Objective To discuss the evaluation and management of fixed sagittal plane imbalance. Methods A comprehensive literature review was performed on the preoperative evaluation of patients with sagittal plane malalignment, as well as the surgical strategies to address sagittal plane deformity. Results Sagittal plane imbalance is often caused by de novo scoliosis or iatrogenic flat back deformity. Understanding the etiology and magnitude of sagittal malalignment is crucial in realignment planning. Objective parameters have been developed to guide surgeons in determining how much correction is needed to achieve favorable outcomes. Currently, the goals of surgery are to restore a sagittal vertical axis < 5 cm, pelvic tilt < 20 degrees, and lumbar lordosis equal to pelvic incidence ± 9 degrees. Conclusion Sagittal plane malalignment is an increasingly recognized cause of pain and disability. Treatment of sagittal plane imbalance varies according to the etiology, location, and severity of the deformity. Fixed sagittal malalignment often requires complex reconstructive procedures that include osteotomy correction. Reestablishing harmonious spinopelvic alignment is associated with significant improvement in health-related quality-of-life outcome measures and patient satisfaction.

  5. A Proposal of New Reference System for the Standard Axial, Sagittal, Coronal Planes of Brain Based on the Serially-Sectioned Images

    PubMed Central

    Park, Jin Seo; Park, Hyo Seok; Shin, Dong Sun; Har, Dong-Hwan; Cho, Zang-Hee; Kim, Young-Bo; Han, Jae-Yong; Chi, Je-Geun

    2010-01-01

    Sectional anatomy of human brain is useful to examine the diseased brain as well as normal brain. However, intracerebral reference points for the axial, sagittal, and coronal planes of brain have not been standardized in anatomical sections or radiological images. We made 2,343 serially-sectioned images of a cadaver head with 0.1 mm intervals, 0.1 mm pixel size, and 48 bit color and obtained axial, sagittal, and coronal images based on the proposed reference system. This reference system consists of one principal reference point and two ancillary reference points. The two ancillary reference points are the anterior commissure and the posterior commissure. And the principal reference point is the midpoint of two ancillary reference points. It resides in the center of whole brain. From the principal reference point, Cartesian coordinate of x, y, z could be made to be the standard axial, sagittal, and coronal planes. PMID:20052359

  6. 1975 Memorial Award Paper. Image generation and display techniques for CT scan data. Thin transverse and reconstructed coronal and sagittal planes.

    PubMed

    Glenn, W V; Johnston, R J; Morton, P E; Dwyer, S J

    1975-01-01

    The various limitations to computerized axial tomographic (CT) interpretation are due in part to the 8-13 mm standard tissue plane thickness and in part to the absence of alternative planes of view, such as coronal or sagittal images. This paper describes a method for gathering multiple overlapped 8 mm transverse sections, subjecting these data to a deconvolution process, and then displaying thin (1 mm) transverse as well as reconstructed coronal and sagittal CT images. Verification of the deconvolution technique with phantom experiments is described. Application of the phantom results to human post mortem CT scan data illustrates this method's faithful reconstruction of coronal and sagittal tissue densities when correlated with actual specimen photographs of a sectioned brain. A special CT procedure, limited basal overlap scanning, is proposed for use on current first generation CT scanners without hardware modification.

  7. 5D CNS+ Software for Automatically Imaging Axial, Sagittal, and Coronal Planes of Normal and Abnormal Second-Trimester Fetal Brains.

    PubMed

    Rizzo, Giuseppe; Capponi, Alessandra; Persico, Nicola; Ghi, Tullio; Nazzaro, Giovanni; Boito, Simona; Pietrolucci, Maria Elena; Arduini, Domenico

    2016-10-01

    The purpose of this study was to test new 5D CNS+ software (Samsung Medison Co, Ltd, Seoul, Korea), which is designed to image axial, sagittal, and coronal planes of the fetal brain from volumes obtained by 3-dimensional sonography. The study consisted of 2 different steps. First in a prospective study, 3-dimensional fetal brain volumes were acquired in 183 normal consecutive singleton pregnancies undergoing routine sonographic examinations at 18 to 24 weeks' gestation. The 5D CNS+ software was applied, and the percentage of adequate visualization of brain diagnostic planes was evaluated by 2 independent observers. In the second step, the software was also tested in 22 fetuses with cerebral anomalies. In 180 of 183 fetuses (98.4%), 5D CNS+ successfully reconstructed all of the diagnostic planes. Using the software on healthy fetuses, the observers acknowledged the presence of diagnostic images with visualization rates ranging from 97.7% to 99.4% for axial planes, 94.4% to 97.7% for sagittal planes, and 92.2% to 97.2% for coronal planes. The Cohen κ coefficient was analyzed to evaluate the agreement rates between the observers and resulted in values of 0.96 or greater for axial planes, 0.90 or greater for sagittal planes, and 0.89 or greater for coronal planes. All 22 fetuses with brain anomalies were identified among a series that also included healthy fetuses, and in 21 of the 22 cases, a correct diagnosis was made. 5D CNS+ was efficient in successfully imaging standard axial, sagittal, and coronal planes of the fetal brain. This approach may simplify the examination of the fetal central nervous system and reduce operator dependency.

  8. Progression of spinal deformity in wheelchair-dependent patients with Duchenne muscular dystrophy who are not treated with steroids: coronal plane (scoliosis) and sagittal plane (kyphosis, lordosis) deformity.

    PubMed

    Shapiro, F; Zurakowski, D; Bui, T; Darras, B T

    2014-01-01

    We determined the frequency, rate and extent of development of scoliosis (coronal plane deformity) in wheelchair-dependent patients with Duchenne muscular dystrophy (DMD) who were not receiving steroid treatment. We also assessed kyphosis and lordosis (sagittal plane deformity). The extent of scoliosis was assessed on sitting anteroposterior (AP) spinal radiographs in 88 consecutive non-ambulatory patients with DMD. Radiographs were studied from the time the patients became wheelchair-dependent until the time of spinal fusion, or the latest assessment if surgery was not undertaken. Progression was estimated using a longitudinal mixed-model regression analysis to handle repeated measurements. Scoliosis ≥ 10° occurred in 85 of 88 patients (97%), ≥ 20° in 78 of 88 (89%) and ≥ 30° in 66 of 88 patients (75%). The fitted longitudinal model revealed that time in a wheelchair was a highly significant predictor of the magnitude of the curve, independent of the age of the patient (p < 0.001). Scoliosis developed in virtually all DMD patients not receiving steroids once they became wheelchair-dependent, and the degree of deformity deteriorated over time. In general, scoliosis increased at a constant rate, beginning at the time of wheelchair-dependency (p < 0.001). In some there was no scoliosis for as long as three years after dependency, but scoliosis then developed and increased at a constant rate. Some patients showed a rapid increase in the rate of progression of the curve after a few years - the clinical phenomenon of a rapidly collapsing curve over a few months. A sagittal plane kyphotic deformity was seen in 37 of 60 patients (62%) with appropriate radiographs, with 23 (38%) showing lumbar lordosis (16 (27%) abnormal and seven (11%) normal). This study provides a baseline to assess the effects of steroids and other forms of treatment on the natural history of scoliosis in patients with DMD, and an approach to assessing spinal deformity in the coronal and

  9. Imaging anatomy of the head and spine. A photographic color atlas of MRI, CT, gross and microscopic anatomy in axial, coronal, and sagittal planes

    SciTech Connect

    Schnitzlein, H.N.; Murtagh, F.R.

    1985-01-01

    This book presents a correlative display of horizontal, coronal, and sagittal sections of the head and spine with a wide array of MRI images, CT scans, and conventional radiographs. Superb full color illustrations of serial dissections emphasize such clinically important areas as the temporal bone, orbit, and cervical spine. The MRI images included are state of the art, and only the highest resolution CT scans appear.

  10. Sagittal plane correction in idiopathic scoliosis.

    PubMed

    de Jonge, Tamás; Dubousset, Jean F; Illés, Tamás

    2002-04-01

    Patients with idiopathic scoliosis who had undergone posterior fusion by means of posterior multisegmented hook instrumentation were studied retrospectively. To present the changes in projected thoracic hypokyphosis and the behavior of lumbar lordosis within and below the fusion. Scoliosis is a three-dimensional deformity of the spine. The idiopathic cases usually exhibit a flattening of the sagittal curves, which had further deteriorated when the Harrington technique was used. The consequences included the flat back, angular increase of the lumbar lordosis below the fusion, and low back pain. Previous studies showed no or only moderate correction of thoracic hypokyphosis when using Cotrel-Dubousset instrumentation or its modifications were used. Harrington rod systems resulted in decreased lumbar lordosis in the fusion area and increased lordosis below the fusion. No background data were found concerning the effects of multisegmented hook instrumentation on the lumbar spine within and below the fusion. For this study, 306 patients with idiopathic scoliosis who had undergone posterior spinal fusion with multisegmented hook systems using the derotation maneuver were analyzed after a mean follow-up period of 5 years and 4 months. The coronal plane curvature, the sagittal plane projection of the thoracic kyphosis, and the lumbar lordosis within and below the fusion were evaluated. The average coronal plane correction was 67.1%. Analysis of the sagittal contours demonstrated that the preoperative thoracic hypokyphosis (less than 20 degrees between T4 and T12) increased by an average of 12 degrees, and that 55.1% of hypokyphotic backs were corrected to the normal range (20 degrees to 40 degrees ). In patients with frank lordosis (kyphosis less than 10 degrees ), the degree of correction was higher (average, 16 degrees ), but complete correction was achieved in only 38.5% of the cases. In patients with mild lordosis (kyphosis between 10 degrees and 20 degrees ), the

  11. The primal sagittal plane of the head: a new concept.

    PubMed

    Gateno, J; Jajoo, A; Nicol, M; Xia, J J

    2016-03-01

    To assess facial form, one has to determine the size, position, orientation, shape, and symmetry of the different facial units. Many of these assessments require a frame of reference. The customary coordinate system used for these assessments is the 'standard anatomical frame of reference', a three-dimensional Cartesian system made by three planes: the sagittal, the axial, and the coronal. Constructing the sagittal plane seems simple, but because of universal facial asymmetry, it is complicated. Depending on the method one selects, one can build hundreds of different planes, never knowing which one is correct. This conundrum can be solved by estimating the sagittal plane a patient would have had if his or her face had developed symmetrically. We call this the 'primal sagittal plane'. To estimate this plane we have developed a mathematical algorithm called LAGER (Landmark Geometric Routine). In this paper, we explain the concept of the primal sagittal plane and present the structure of the LAGER algorithm. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  12. Sagittal plane deformity: an overview of interpretation and management

    PubMed Central

    Roussouly, Pierre

    2010-01-01

    The impact of sagittal plane alignment on the treatment of spinal disorders is of critical importance. A failure to recognise malalignment in this plane can have significant consequences for the patient not only in terms of pain and deformity, but also social interaction due to deficient forward gaze. A good understanding of the principles of sagittal balance is vital to achieve optimum outcomes when treating spinal disorders. Even when addressing problems in the coronal plane, an awareness of sagittal balance is necessary to avoid future complications. The normal spine has lordotic curves in the cephalad and caudal regions with a kyphotic curve in between. Overall, there is a positive correlation between thoracic kyphosis and lumbar lordosis. There are variations on the degree of normal curvature but nevertheless this shape allows equal distribution of forces across the spinal column. It is the disruption of this equilibrium by pathological processes or, as in most cases, ageing that results in deformity. This leads to adaptive changes in the pelvis and lower limbs. The effects of limb alignment on spinal posture are well documented. We now also know that changes in pelvic posture also affect spinal alignment. Sagittal malalignment presents as an exaggeration or deficiency of normal lordosis or kyphosis. Most cases seen in clinical practise are due to kyphotic deformity secondary to inflammatory, degenerative or post-traumatic disorders. They may also be secondary to infection or tumours. There is usually pain and functional disability along with concerns about self-image and social interaction due to inability to maintain a horizontal gaze. The resultant pelvic and lower limb posture is an attempt to restore normal alignment. Addressing this complex problem requires detailed expertise and awareness of the potential pitfalls surrounding its treatment. PMID:20567858

  13. Sagittal plane deformity: an overview of interpretation and management.

    PubMed

    Roussouly, Pierre; Nnadi, Colin

    2010-11-01

    The impact of sagittal plane alignment on the treatment of spinal disorders is of critical importance. A failure to recognise malalignment in this plane can have significant consequences for the patient not only in terms of pain and deformity, but also social interaction due to deficient forward gaze. A good understanding of the principles of sagittal balance is vital to achieve optimum outcomes when treating spinal disorders. Even when addressing problems in the coronal plane, an awareness of sagittal balance is necessary to avoid future complications. The normal spine has lordotic curves in the cephalad and caudal regions with a kyphotic curve in between. Overall, there is a positive correlation between thoracic kyphosis and lumbar lordosis. There are variations on the degree of normal curvature but nevertheless this shape allows equal distribution of forces across the spinal column. It is the disruption of this equilibrium by pathological processes or, as in most cases, ageing that results in deformity. This leads to adaptive changes in the pelvis and lower limbs. The effects of limb alignment on spinal posture are well documented. We now also know that changes in pelvic posture also affect spinal alignment. Sagittal malalignment presents as an exaggeration or deficiency of normal lordosis or kyphosis. Most cases seen in clinical practise are due to kyphotic deformity secondary to inflammatory, degenerative or post-traumatic disorders. They may also be secondary to infection or tumours. There is usually pain and functional disability along with concerns about self-image and social interaction due to inability to maintain a horizontal gaze. The resultant pelvic and lower limb posture is an attempt to restore normal alignment. Addressing this complex problem requires detailed expertise and awareness of the potential pitfalls surrounding its treatment.

  14. High-resolution sagittal and coronal reformatted CT images of the larynx

    SciTech Connect

    Silverman, P.M.; Johnson, G.A.; Korobkin, M.

    1983-04-01

    Computed tomography has become the major technique for evaluation of patients with laryngeal corcinoma and trauma to the larynx. The routine examination usually consists of 5 mm contiguous selection through the larynx in quiet respiration. Reformatted images obtained from these sections have not been of clinical value, in part because of the poor resolution of these images. In the past, thin-section scanning (1.5 mm collimation) has been impractical because of the significant time required to scan the entire larynx. By using the technique of rapid sequential scanning with automated table incrementation this logistic difficulty can be overcome, and the total thin-section examination may be performed in less than 9 min. Sophisticated computer software allows rapid reformatting of transaxial images in sagittal and coronal planes. This report illustates the normal and abnormal appearance of the larynx on coronal and sagittal reformatted images and compares reformatted images using the routine technique to those using the thin-section technique.

  15. Multisection sagittal and coronal magnetic resonance imaging of the mediastinum and hila: work in progress

    SciTech Connect

    Webb, W.R.; Gamsu, G.; Crooks, L.E.

    1984-02-01

    Sagittal or coronal thoracic magnetic resonance (MR) images were obtained in 7 individuals - 4 normal subjects and 3 patients with thoracic masses. In 2 of the abnormal cases, sagittal or coronal MR provided significant anatomic information that was either less evident or invisible on transaxial MR or computed tomographic (CT) images or CT reformations. In the third abnormal patient, a pretracheal lymph node was more clearly seen on transaxial images than on coronal images.

  16. Radiographic comparison of sagittal plane stability between cast and boots.

    PubMed

    Kadakia, Anish R; Espinosa, Norman; Smerek, Jonathan; White, Kacey; Myerson, Mark S; Jeng, Clifford L

    2008-04-01

    The importance of postoperative stability when considering surgery on the foot and ankle cannot be overestimated. To our knowledge, no literature exists to describe the radiographic sagittal plane motion with varying types of immobilization devices. The purpose of this study was to evaluate the sagittal plane range of motion allowed in different types of boots in comparison to fiberglass cast treatment on normal human subjects. Ten healthy volunteers without preexisting foot and ankle pathology were chosen for the study. Five types of immobilization were selected for testing, including 4 off-the-shelf braces and a fiberglass cast. Maximum dorsiflexion and maximum plantarflexion lateral radiographs were taken without any immobilization and in the fiberglass cast and all walkers. The mean range of motion in a fiberglass cast was 8.4 degrees (SD, 4.3 degrees); FP Foam Walker, 16 degrees (SD, 6.7 degrees); XP Pneumatic Walker, 15.4 degrees (SD, 5.6 degrees); Donjoy Max Walker, 19.1 degrees (5.4 degrees); and the SP Walker, 39 degrees (SD, 10.7 degrees). The cast was noted to have a significantly greater limitation of sagittal plane motion compared to all other forms of immobilization (p < 0.05). Sagittal plane motion is restricted significantly more with a fiberglass cast compared to the FP Foam Walker, and XP Pneumatic Walker, Donjoy Max Walker, and the SP Walker. Therefore, in patients whom maximum restriction of sagittal plane motion is required, use of a fiberglass cast offers superior control.

  17. Sagittal plane balancing in the total knee arthroplasty.

    PubMed

    Manson, Theodore T; Khanuja, Harpal S; Jacobs, Michael A; Hungerford, Marc W

    2009-01-01

    Postoperative stiffness or instability may result from a total knee arthroplasty imbalanced in the sagittal plane. Total knee arthroplasty instrumentation systems differ in the basic strategies used to assure this balance. In an anterior referencing system, changes in femoral size affect flexion gap tightness, and femoral size selection is paramount to assure sagittal plane balance. Conversely, in posterior referencing systems, femoral size changes do not affect the flexion gap but, rather, influence femoral component-patella articulation. Flexion/extension gap systems use calibrated spacer blocks to ensure gap balance but do not guarantee midrange stability; if used incorrectly, they may cause component malposition and joint line elevation. The authors reviewed the strengths and weaknesses of system types and provided system-specific troubleshooting guidelines for clinicians addressing intraoperative sagittal plane imbalance.

  18. Percutaneous sagittal plane closing wedge osteotomy of the first metatarsal.

    PubMed

    Lui, Tun Hing

    2014-02-01

    Osteotomy of the first metatarsal in the sagittal plane is useful in correction of numerous deformity of the foot. Plantarflexion osteotomy of the first metatarsal can be used to treat hallux rigidus, hallux limitus, forefoot varus in flatfoot deformity and iatrogenic metatarsus primus elevates. Dorsiflexion osteotomy of the first metatarsal is an important component in surgical correction of pes cavus. It is also indicated in recalcitrant diabetic neuropathic ulcers at the first metatarsal head. We described a minimally invasive technique of sagittal plane corrective osteotomy of the first metatarsal, which can be either a plantarflexion or dorsiflexion one.

  19. Sagittal plane deformity in bicondylar tibial plateau fractures.

    PubMed

    Streubel, Philipp N; Glasgow, Donald; Wong, Ambrose; Barei, David P; Ricci, William M; Gardner, Michael J

    2011-09-01

    To evaluate the prevalence and magnitude of sagittal plane deformity in bicondylar tibial plateau fractures. Retrospective radiographic review. Two Level I trauma centers. Sagittal inclination of the medial and lateral plateau measured in relation to the longitudinal axis of the tibia using computed tomographic reconstruction images. Seventy-four patients (mean age, 49 years; range, 16-82 years; 64% male) with acute bicondylar tibial plateau fractures (Orthopaedic Trauma Association 41C, Schatzker VI) treated from October 2006 to July 2009. The average sagittal plane angulation of the lateral plateau was 9.8° posteriorly (range, 17° anteriorly to 37° posteriorly). The medial plateau was angulated 4.1° posteriorly on average (range, 16° anteriorly to 31° posteriorly). Forty-two lateral plateaus were angulated more than 5° from the "normal" anatomic slope (defined as 5° of posterior tibial slope). Of these, 76% were angulated posteriorly. Forty-three (58%) of the medial plateaus were angulated greater than 5° from normal, of which only 47% were inclined posteriorly (P = 0.019 compared with lateral plateaus). In 68% of patients, the difference between medial and lateral plateaus was greater than 5°; the average intercondylar slope difference was 9° (range, 0°-31°; P < 0.001). Spanning external fixation did not affect the slope of either the medial or lateral tibial plateau. Intraobserver and interobserver correlations were high for both the medial and lateral plateaus (r > 0.81, P < 0.01). Considerable sagittal plane deformity exists in the majority of bicondylar tibial plateau fractures. The lateral plateau has a higher propensity for sagittal angulation and tends to have increased posterior slope. Most patients have a substantial difference between the lateral and medial plateau slopes. The identification of this deformity allows for accurate preoperative planning and specific reduction maneuvers to restore anatomic alignment.

  20. Sagittal plane trunk posture influences patellofemoral joint stress during running.

    PubMed

    Teng, Hsiang-Ling; Powers, Christopher M

    2014-10-01

    Cross-sectional, repeated-measures. Objectives To examine the association between sagittal plane trunk posture and patellofemoral joint (PFJ) stress, and to determine whether modifying sagittal plane trunk posture influences PFJ stress during running. Patellofemoral pain is the most common injury among runners and is thought to be the result of elevated PFJ stress. While sagittal plane trunk posture has been shown to influence tibiofemoral joint mechanics, no study has examined the influence of trunk posture on PFJ kinetics. Twenty-four asymptomatic recreational runners (12 women, 12 men) ran overground at a speed of 3.4 m/s under 3 trunk-posture conditions: self-selected, flexed, and extended. Trunk and knee kinematics, ground reaction forces, and electromyographic signals from selected lower extremity muscles were obtained. A previously described PFJ biomechanical model was used to quantify PFJ stress. The mean ± SD trunk flexion angles under the self-selected, flexed, and extended running conditions were 7.3° ± 3.6°, 14.1° ± 4.8°, and 4.0° ± 3.9°, respectively. A significant inverse relationship was observed between mean trunk flexion angle and peak PFJ stress during the self-selected condition (r = -0.60, P = .002). Peak PFJ stress was significantly lower in the flexed condition (mean ± SD, 20.2 ± 3.4 MPa; P<.001) and significantly higher in the extended condition (23.1 ± 3.4 MPa; P<.001) compared to the self-selected condition (21.5 ± 3.2 MPa). Sagittal plane trunk posture has a significant influence on PFJ kinetics during running. Incorporation of a forward trunk lean may be an effective strategy to reduce PFJ stress during running.

  1. Condylar surface CT value in sagittal plane before and after sagittal split ramus osteotomy.

    PubMed

    Ueki, Koichiro; Yoshizawa, Kunio; Moroi, Akinori; Iguchi, Ran; Kosaka, Akihiko; Ikawa, Hiroumi; Hotta, Asami; Tsutsui, Takamitsu; Saito, Yuki; Fukaya, Kenichi; Hiraide, Ryota; Takayama, Akihiro; Tsunoda, Tatsuya

    2017-06-01

    The purpose of this study was to evaluate the relationship between computed tomography (CT) values of the condylar surface and temporomandibular joint (TMJ) disc position in the sagittal plane before and after sagittal split ramus osteotomy (SSRO) setback surgery, retrospectively. The subjects were 75 patients (150 condyles) who underwent bilateral SSRO setback surgery. They were divided into two groups (42 symmetric patients and 33 asymmetric patients). Maximum CT values (pixel values) of five points of the condylar surface and condylar height, length, fossa height, fossa length, and ramus angle in the sagittal plane were measured preoperatively and 1 year postoperatively. Disc position was classified as anterior disc displacement, anterior type, fully covered type, and posterior type, both pre- and postoperatively, using magnetic resonance imaging (MRI). Postoperative value was significantly higher than preoperative one in CT value of 135° (P = 0.0199) and 180° (0.0363), in the non-deviation side in the asymmetry group. The anterior disc displacement group was significantly larger than those of some other areas pre- and postoperatively in the CT value of 0° point (P < 0.05). This study suggested that CT value of the posterior site of the condylar surface could change in the non-deviation side in the asymmetry group after 1 year SSRO, and the condyle with anterior displacement showed high CT value at the anterior site of the condyle before and after surgery.

  2. Maintenance of sagittal plane alignment after surgical correction of spinal deformity in patients with cerebral palsy.

    PubMed

    Sink, Ernest L; Newton, Peter O; Mubarak, Scott J; Wenger, Dennis R

    2003-07-01

    A case series of patients with cerebral palsy treated for spinal deformity using Luque-Galveston instrumentation was retrospectively analyzed. To analyze the incidence and risk factors for postoperative loss of sagittal plane correction initially obtained with Luque-Galveston instrumentation in patients with cerebral palsy. The Luque-Galveston instrumentation technique has been widely adopted in the treatment of neuromuscular spinal deformity. Although the results in the coronal plane have been generally satisfactory, problems in maintaining sagittal plane correction have been noted. For this study, 41 patients with spastic quadriplegia who underwent surgical correction of spinal deformity between 1990 and 1998 were reviewed with attention given to the maintenance of sagittal plane correction. Preoperative, initial postoperative, and most recent radiographs were measured to determine the sagittal Cobb angle from T5 to T12, T12 to L2, and L1 to S1. On the basis of the preoperative sagittal alignment, patients were separated into two groups: those with preoperative hyperkyphosis (T5-T12 >or= 50 degrees, T12-L2 >or= 20 degrees, or L1-S1 >or= 0 degrees ) and those with normal or decreased kyphosis. The radiographs were assessed for proximal hardware failure/pullout or junctional kyphosis (>20 degrees ), and for backing out of the Galveston rods distally. Of the 41 patients, 29 underwent correction of their deformity with Luque-Galveston instrumentation alone. In 21 of these patients anterior release-fusion preceded the posterior procedure. Additional anterior lumbar instrumentation was used in 12 patients. Proximal loss of correction or implant failure occurred in 13 patients (32%). In four of these patients junctional kyphosis developed at the cephalad extent of the instrumentation, and nine patients had proximal hardware failure/pullout. Posterior migration of the distal end of the Galveston rods occurred in five patients (12%). Four of these five patients had

  3. Unilateral coronal synostosis: can we trust the sagittal suture as a landmark for the underlying superior sagittal sinus?

    PubMed

    Protzenko Cervante, Tatiana; Arnaud, Eric; Brunelle, Francis; Di Rocco, Federico

    2016-05-01

    OBJECTIVE The sagittal suture is usually considered an external anatomical landmark, indicating the location of the superior sagittal sinus (SSS) for surgical approaches. Children with unilateral coronal synostosis (UCS) often present with an important deviation of the sagittal suture. Because these patients usually undergo frontal reconstruction or even endoscope-assisted minimally invasive procedures, it is imperative to know the location of the SSS. The aim of this investigation was to study the anatomical relationship between the SSS and the sagittal suture in children with anterior plagiocephaly. METHODS The authors retrospectively studied the relationship between the sagittal sinus and the sagittal suture at 5 points: nasion, midpoint nasion-bregma, bregma, midpoint bregma-lambda, and lambda. The study analyzed CT scans of 50 children with UCS admitted to the craniofacial unit of Necker Enfants Malades Hospital between March 2006 and March 2013 and compared them with 50 control children with no evidence of craniosynostosis, bone disease, or genetic syndromes. The authors also analyzed the presence of extracerebral fluid collection and ventricular asymmetry in children with UCS. RESULTS Fifty-six percent of patients had anterior right UCS and 44% had left-sided UCS. Type I UCS was seen in 1 patient, Type IIA in 20 patients, Type IIB in 20 patients, and Type III in 9 patients. The authors found that the nasion is usually deviated to the ipsilateral side of the synostosis, the bregma contralaterally, and the lambda ipsilaterally. The gap distances between the reference point and the SSS were 0-7.3 mm (mean 1.4 mm) at the nasion; 0-16.7 mm (mean 3.8 mm) at the midpoint nasion-bregma; 0-12 mm (mean 5.8 mm) at the bregma; 0-9.5 mm (mean 3 mm) at the midpoint bregma-lambda; and 0-11.6 mm (mean 5.5 mm) at the lambda. Conversely, a discrepancy of more than 1 mm between the SSS and the position of the suture was found only in 7 control cases (14%). Of patients with UCS

  4. Clinically acceptable agreement between the ViMove wireless motion sensor system and the Vicon motion capture system when measuring lumbar region inclination motion in the sagittal and coronal planes.

    PubMed

    Mjøsund, Hanne Leirbekk; Boyle, Eleanor; Kjaer, Per; Mieritz, Rune Mygind; Skallgård, Tue; Kent, Peter

    2017-03-21

    Wireless, wearable, inertial motion sensor technology introduces new possibilities for monitoring spinal motion and pain in people during their daily activities of work, rest and play. There are many types of these wireless devices currently available but the precision in measurement and the magnitude of measurement error from such devices is often unknown. This study investigated the concurrent validity of one inertial motion sensor system (ViMove) for its ability to measure lumbar inclination motion, compared with the Vicon motion capture system. To mimic the variability of movement patterns in a clinical population, a sample of 34 people were included - 18 with low back pain and 16 without low back pain. ViMove sensors were attached to each participant's skin at spinal levels T12 and S2, and Vicon surface markers were attached to the ViMove sensors. Three repetitions of end-range flexion inclination, extension inclination and lateral flexion inclination to both sides while standing were measured by both systems concurrently with short rest periods in between. Measurement agreement through the whole movement range was analysed using a multilevel mixed-effects regression model to calculate the root mean squared errors and the limits of agreement were calculated using the Bland Altman method. We calculated root mean squared errors (standard deviation) of 1.82° (±1.00°) in flexion inclination, 0.71° (±0.34°) in extension inclination, 0.77° (±0.24°) in right lateral flexion inclination and 0.98° (±0.69°) in left lateral flexion inclination. 95% limits of agreement ranged between -3.86° and 4.69° in flexion inclination, -2.15° and 1.91° in extension inclination, -2.37° and 2.05° in right lateral flexion inclination and -3.11° and 2.96° in left lateral flexion inclination. We found a clinically acceptable level of agreement between these two methods for measuring standing lumbar inclination motion in these two cardinal movement planes. Further

  5. Human foot placement and balance in the sagittal plane.

    PubMed

    Millard, Matthew; Wight, Derek; McPhee, John; Kubica, Eric; Wang, David

    2009-12-01

    Foot placement has long been recognized as the primary mechanism that humans use to restore balance. Many biomechanists have examined where humans place their feet during gait, perturbations, and athletic events. Roboticists have also used foot placement as a means of control but with limited success. Recently, Wight et al. (2008, "Introduction of the Foot Placement Estimator: A Dynamic Measure of Balance for Bipedal Robotics," ASME J. Comput. Nonlinear Dyn., 3, p. 011009) introduced a planar foot placement estimator (FPE) algorithm that will restore balance to a simplified biped that is falling. This study tested the FPE as a candidate function for sagittal plane human-foot-placement (HFP) by recording the kinematics of 14 healthy subjects while they performed ten walking trials at three speeds. The FPE was highly correlated with HFP (rho>or=0.997) and its accuracy varied linearly from 2.6 cm to -8.3 cm as walking speed increased. A sensitivity analysis revealed that assumption violations of the FPE cannot account for the velocity-dependent changes in FPE-HFP error suggesting that this behavior is volitional.

  6. Sagittal plane momentum control during walking in elderly fallers.

    PubMed

    Fujimoto, Masahiro; Chou, Li-Shan

    2016-03-01

    The purpose of this study was to examine sagittal plane momentum control during walking with the use of center of mass (COM) velocity and acceleration. COM control in the antero-posterior direction during walking of healthy young and elderly adults, and elderly fallers (n=15/group) was examined. Using a single-link-plus-foot inverted pendulum model, boundaries for the region of stability were determined based on the COM position at toe-off and its instantaneous velocity or the peak acceleration prior to toe-off (ROSv or ROSa, respectively). Although no significant difference in forward COM velocity was detected between healthy young and elderly subjects, the peak forward COM acceleration differed significantly, suggesting age-related differences in momentum control during walking. Elderly fallers demonstrated significantly slower forward COM velocities and accelerations and placed their COM significantly more anterior than healthy young and elderly subjects at toe-off, which resulted in their COM position-velocity combination located within the ROSv. Similar results were obtained in the ROSa, where elderly fallers demonstrated a larger stability margin than healthy young and elderly subjects. Significantly slower peak COM accelerations could be indicative of a poor momentum control ability, which was more pronounced in elderly fallers. Examining COM acceleration, in addition to its velocity, would provide a greater understanding of person's momentum control, which would allow us to better reveal underlying mechanisms of gait imbalance or falls. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Sagittal plane coordination dynamics of typically developing gait.

    PubMed

    Worster, Kate; Valvano, Joanne; Carollo, James J

    2015-05-01

    Individuals who undergo an instrumented gait analysis often have an aberrant gait pattern due to neuromuscular impairments that adversely affect their coordination. Conventional instrumented gait analysis descriptors fail to capture the complex coordination dynamics of gait. This paper presents a straightforward methodology for generating descriptors of coordination dynamics based on dynamical systems theory and provides the largest reported dataset of sagittal plane coordination measures, including adjacent and non-adjacent segment pairings, from individuals free of gait pathology walking over-ground. Tri-planar marker trajectories from 104 unimpaired subjects between the ages of 8 and 66 years were collected as they walked at a self-selected speed on a level surface. Phase portraits for the pelvis, thigh, shank, and foot and continuous relative phase diagrams for the segment pairs of pelvis-thigh, thigh-shank, shank-foot, and thigh-foot were calculated. The low coefficients of variation for each coordination curve are comparable to inter-subject coefficients of variation for kinematic curves, narrow confidence intervals for relative phase angles at four essential footfall conditions, and small standard deviation bands of the continuous relative phase diagrams are evidence that these curves characterize the coordination dynamics of normal gait. These findings support the use of this normative dataset as a reference for coordination studies in the clinic or research laboratory. Improving our understanding of gait strategies from the level of coordination and characterizing the natural variability in gait patterns offer a means to enhance our understanding of atypical gait patterns. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Coupling between sagittal and frontal plane deformity correction in idiopathic thoracic scoliosis and its relationship with postoperative sagittal alignment.

    PubMed

    Luk, Keith D K; Vidyadhara, Srinivasa; Lu, D S; Wong, Y W; Cheung, W Y; Cheung, Kenneth M C

    2010-05-15

    Prospective clinical-radiographic study. To investigate the natural coupling behavior between frontal deformity correction and the simultaneous changes in thoracic kyphosis, and to examine how the postoperative thoracic sagittal realignment relates to this natural coupling behavior. Restoration of the sagittal alignment is one of the fundamental goals in scoliosis correction surgery. It is generally achieved by rod precontouring intraoperatively. However, clinical studies suggested that postoperative sagittal realignment seems to be more affected by the inherent properties of the spine rather than the instrumentation or the surgical maneuver. Ninety-eight idiopathic scoliosis patients with thoracic curves treated with one-stage posterior spinal fusion, using corrective segmental spinal instrumentation (hook-rod or pedicle screw-rod constructs) were investigated. Pre- and postoperative frontal and sagittal alignments were measured by standing anteroposterior and lateral radiographs. Preoperative frontal plane flexibility was assessed by the fulcrum bending radiograph in the standard manner, an additional radiograph was taken in the lateral plane, to assess how this frontal correction force affects sagittal plane alignment (lateral fulcrum bending radiograph). When thoracic frontal deformity was corrected under fulcrum bending, coupled changes in the thoracic kyphosis demonstrated 3 different patterns: thoracic kyphosis increased in 25 patients with a mean kyphosis of 9 degrees to 19 degrees, decreased in 45 with a mean of 34 degrees to 21 degrees and remained unchanged (within 3 degrees ) in 28 with a mean of 19 degrees to 18 degrees. After surgery, the direction of correction of thoracic kyphosis significantly correlated with the coupling patterns demonstrated on fulcrum bending radiographs (r = 0.579, P < 0.001). However, the actual postoperative thoracic kyphosis angle cannot be predicted by the preoperative lateral fulcrum bending radiograph. There was no

  9. Global sagittal axis: a step toward full-body assessment of sagittal plane deformity in the human body.

    PubMed

    Diebo, Bassel G; Oren, Jonathan H; Challier, Vincent; Lafage, Renaud; Ferrero, Emmanuelle; Liu, Shian; Vira, Shaleen; Spiegel, Matthew Adam; Harris, Bradley Yates; Liabaud, Barthelemy; Henry, Jensen K; Errico, Thomas J; Schwab, Frank J; Lafage, Virginie

    2016-10-01

    the human body in the sagittal plane. The GSA correlated highly with spinopelvic and lower-extremities sagittal parameters and exhibited remarkable correlations with HRQOL, which exceeded other commonly used parameters.

  10. Proprioceptive acuity in the frontal and sagittal planes of the knee: a preliminary study

    PubMed Central

    Dhaher, Yasin Y.

    2012-01-01

    Though the knee experiences three-dimensional loading during everyday tasks, assessment of proprioceptive acuity has typically been limited to the primary direction of movement, knee flexion and extension. While loading in the constrained directions (varus/valgus and internal/external rotation) may contribute to injury and joint disease, little information is available regarding proprioceptive acuity in these planes of movement. The primary aim of this study was to characterize proprioceptive acuity in the frontal plane (varus/valgus) and to compare it with sagittal plane (flexion/extension) proprioceptive acuity in healthy subjects. Proprioception was assessed in 17 young, healthy subjects (11 females, 6 males, ages 21–33 years) using the threshold to detection of passive movement (TDPM). TDPM was found to be significantly (P < 0.001) lower in the frontal plane [valgus: mean (SD) 0.60 (0.20)° and varus: 0.58 (0.23)°] compared with the sagittal plane [extension: 0.78 (0.34)°, flexion: 0.82 (0.48)°]; however, no significant differences were noted within the same plane of movement. Results from this preliminary study may suggest more accurate proprioceptive acuity in the frontal plane compared with the sagittal plane. While further examination is necessary to confirm this relationship, more accurate frontal plane acuity may reflect a protective neural mechanism which enables more precise neuromuscular control of the joint in this constrained plane of movement. PMID:21140163

  11. The influence of computer-assisted surgery on rotational, coronal and sagittal alignment in revision total knee arthroplasty

    PubMed Central

    2014-01-01

    Background Despite good results of primary total knee arthroplasty (TKA), the number of revision total knee arthroplasties (rTKAs) is rising. Proper implant position is essential, since malposition leads to worse clinical outcome. In rTKA most anatomical landmarks have disappeared because of extensive bone loss, making it more difficult to adequately implant the knee prosthesis. In primary TKA, computer-assisted surgery (CAS) leads to better prosthetic alignment than mechanical navigation guides. Literature about the use of CAS in rTKA is scarce though, and the effect on rotational prosthetic alignment has not been investigated yet. Hence the primary objective of this study is to compare rotational prosthetic alignment when using CAS in rTKA compared to a mechanical navigation guide. Secondary objectives are to compare prosthetic alignment in the coronal and sagittal planes. It is hypothesized that CAS leads to better rotational, coronal and sagittal prosthetic alignment when used during rTKA. Methods/Design A prospective clinical intervention study with use of a historical control group will be conducted. Forty-four patients with a minimum age of 18 to be admitted for CAS-rTKA between September 2012 and September 2015 will be included in the intervention group. Forty-four patients with a minimum age of 18 who underwent rTKA with the use of a mechanical navigation guide between January 2002 and April 2012 will form the historical control group. Both groups will be matched according to gender and type of revision prosthesis. Rotational prosthesis alignment will be evaluated using a CT-scan of the knee joint. Discussion Proper implant position is essential, since malposition leads to worse clinical outcome. Several studies show a significantly positive influence of CAS on prosthetic alignment in primary TKA, but literature about the use of CAS in rTKA is limited. The purpose of this study is thus to investigate the influence of CAS during rTKA on postoperative

  12. Reliability and reproducibility analysis of the Cobb angle and assessing sagittal plane by computer-assisted and manual measurement tools

    PubMed Central

    2014-01-01

    Background Although many studies on reliability and reproducibility of measurement have been performed on coronal Cobb angle, few results about reliability and reproducibility are reported on sagittal alignment measurement including the pelvis. We usually use SurgimapSpine software to measure the Cobb angle in our studies; however, there are no reports till date on its reliability and reproducible measurements. Methods Sixty-eight standard standing posteroanterior whole-spine radiographs were reviewed. Three examiners carried out the measurements independently under the settings of manual measurement on X-ray radiographies and SurgimapSpine software on the computer. Parameters measured included pelvic incidence, sacral slope, pelvic tilt, Lumbar lordosis (LL), thoracic kyphosis, and coronal Cobb angle. SPSS 16.0 software was used for statistical analyses. The means, standard deviations, intraclass and interclass correlation coefficient (ICC), and 95% confidence intervals (CI) were calculated. Results There was no notable difference between the two tools (P = 0.21) for the coronal Cobb angle. In the sagittal plane parameters, the ICC of intraobserver reliability for the manual measures varied from 0.65 (T2–T5 angle) to 0.95 (LL angle). Further, for SurgimapSpine tool, the ICC ranged from 0.75 to 0.98. No significant difference in intraobserver reliability was found between the two measurements (P > 0.05). As for the interobserver reliability, measurements with SurgimapSpine tool had better ICC (0.71 to 0.98 vs 0.59 to 0.96) and Pearson’s coefficient (0.76 to 0.99 vs 0.60 to 0.97). The reliability of SurgimapSpine measures was significantly higher in all parameters except for the coronal Cobb angle where the difference was not significant (P > 0.05). Conclusion Although the differences between the two methods are very small, the results of this study indicate that the SurgimapSpine measurement is an equivalent measuring tool to the traditional manual

  13. Reliability and reproducibility analysis of the Cobb angle and assessing sagittal plane by computer-assisted and manual measurement tools.

    PubMed

    Wu, Weifei; Liang, Jie; Du, Yuanli; Tan, Xiaoyi; Xiang, Xuanping; Wang, Wanhong; Ru, Neng; Le, Jinbo

    2014-02-06

    Although many studies on reliability and reproducibility of measurement have been performed on coronal Cobb angle, few results about reliability and reproducibility are reported on sagittal alignment measurement including the pelvis. We usually use SurgimapSpine software to measure the Cobb angle in our studies; however, there are no reports till date on its reliability and reproducible measurements. Sixty-eight standard standing posteroanterior whole-spine radiographs were reviewed. Three examiners carried out the measurements independently under the settings of manual measurement on X-ray radiographies and SurgimapSpine software on the computer. Parameters measured included pelvic incidence, sacral slope, pelvic tilt, Lumbar lordosis (LL), thoracic kyphosis, and coronal Cobb angle. SPSS 16.0 software was used for statistical analyses. The means, standard deviations, intraclass and interclass correlation coefficient (ICC), and 95% confidence intervals (CI) were calculated. There was no notable difference between the two tools (P = 0.21) for the coronal Cobb angle. In the sagittal plane parameters, the ICC of intraobserver reliability for the manual measures varied from 0.65 (T2-T5 angle) to 0.95 (LL angle). Further, for SurgimapSpine tool, the ICC ranged from 0.75 to 0.98. No significant difference in intraobserver reliability was found between the two measurements (P > 0.05). As for the interobserver reliability, measurements with SurgimapSpine tool had better ICC (0.71 to 0.98 vs 0.59 to 0.96) and Pearson's coefficient (0.76 to 0.99 vs 0.60 to 0.97). The reliability of SurgimapSpine measures was significantly higher in all parameters except for the coronal Cobb angle where the difference was not significant (P > 0.05). Although the differences between the two methods are very small, the results of this study indicate that the SurgimapSpine measurement is an equivalent measuring tool to the traditional manual in coronal Cobb angle, but is advantageous in spino

  14. Sectional anatomy of the adrenal gland in the coronal plane.

    PubMed

    Ma, Gang; Liu, Shu Wei; Zhao, Zhen Mei; Lin, Xiang Tao; Lou, Li; Li, Zhen Ping; Tang, Yu Chun; Zhong, Shi Zhen

    2008-05-01

    To provide practical anatomic data for the imaging diagnosis and surgical treatment of adrenal disease, we investigated the anatomy of the adrenal gland and its relationships to regional structures using 31 sets of serial coronal sections of upper abdomen of Chinese adult cadavers and correlated coronal magnetic resonance (MR) images of ten upper abdomens of adult healthy volunteers and coronal reconstructed multislice spiral computed tomography (MSCT) images of five patients without lesions in the adrenal gland. The adrenal glands were visualized mainly on the successive coronal sections between 18 mm anterior to the posterior margin of inferior vena cava and 24 mm posterior to the posterior margin of inferior vena cava. In general, the left adrenal gland was visualized two sections earlier than the right adrenal gland. On the plane through the anterior parts of bilateral renal hili (A18), the appearance rate of bilateral adrenal glands was 100%, and the maximal measurements of bilateral adrenal glands were visualized. The length, width, thickness of right adrenal body, thickness of medial limb and lateral limb were, respectively, 34.02 +/- 2.12 mm, 10.91 +/- 0.89 mm, 5.82 +/- 0.26 mm, 2.78 +/- 0.08 mm, 2.62 +/- 0.06 mm, whereas the measurements of left adrenal gland were 28.31 +/- 2.46 mm, 18.40 +/- 1.06 mm, 6.84 +/- 0.24 mm, 3.02 +/- 0.08 mm, 2.86 +/- 0.07 mm, respectively. The coronal plane has superior advantage in showing the bilateral adrenal glands. The shapes of adrenal glands are various, whereas the range of adrenal thickness is quite narrow. The thickness of adrenal medial and lateral limbs, especially the thickness of lateral limb are useful for the diagnosis of the bilateral adrenocortical disease.

  15. Long-term effects of the Chêneau brace on coronal and sagittal alignment in adolescent idiopathic scoliosis.

    PubMed

    Fang, Ming-Qiao; Wang, Chong; Xiang, Guang-Heng; Lou, Chao; Tian, Nai-Feng; Xu, Hua-Zi

    2015-10-01

    The aim of the present study was to retrospectively evaluate progressive correction of coronal and sagittal alignment and pelvic parameters in patients treated with a Chêneau brace. Thirty-two patients with adolescent idiopathic scoliosis (AIS) were assessed before initiation of bracing treatment and at the final follow-up. Each patient underwent radiological examinations, and coronal, sagittal, and pelvic parameters were measured. No statistically significant modification of the Cobb angle was noted. The pelvic incidence remained unchanged in 59% of the cases and increased in 28% of the cases. The sacral slope decreased in 34% of the cases but remained unchanged in 50%. Thoracic kyphosis and lumbar lordosis were significantly decreased, whereas the sagittal vertical axis was significantly increased from a mean of -44.0 to -30.2 mm (p = 0.02). The mean pelvic tilt increased significantly from 4.5° to 8.3° (p = 0.002). The Chêneau brace can be useful for preventing curvature progression in patients with AIS. However, the results of this study reveal high variability in the effect of brace treatment on sagittal and pelvic alignment. Treatment with the Chêneau brace may also influence sagittal global balance.

  16. Sagittal plane alignment of the spine and gravity: a radiological and clinical evaluation.

    PubMed

    Legaye, Jean; Duval-Beaupère, Ginette

    2005-04-01

    Analysis of the sagittal balance of the spine includes the study of the spinal curves and of the pelvis in the sagittal plane. It therefore requires full-spine lateral radiographs. The sagittal balance of the spine was studied in forty-nine young adults. Strong correlations were observed between parameters related to the pelvis ("pelvic incidence angle", "sacral slope" and "pelvic tilting"), and the sagittal spinal curves ("lordosis" and "kyphosis"). We therefore propose to begin the evaluation of the sagittal plane alignment of the spine in clinical practice with measurement of the pelvic incidence angle. The relationship between the pelvic incidence angle and the sacral slope, as well as between the sacral slope and lordosis, is then assessed, and these are related to each other. The use of a graphic abacus facilitates assessment of the physiological comparison of the measured values and of the relationship between pelvic and spinal parameters, within their range of physiological variability. This analysis of the sagittal alignment of the spine also considers its dynamic aspect and the importance of gravity load and of muscular contraction on the lumbar structures. These data have been published previously and are recalled here. Three basic patterns of disruption of the relations between parameters may be encountered: a sacral slope angle exceeding the value expected considering the measured pelvic incidence angle (owing to fixed flexion contracture of the hips), excessive lordosis with regard to the observed sacral slope angle (with hyperkyphosis at the thoracic level) and stiff hypolordosis with pelvic retroversion. These three conditions are analysed in the light of the repercussions of the gravity load on the lumbar structures. A convenient method is thus available for functional analysis of the sagittal balance of the spine.

  17. Bilateral coronal and sagittal synostosis in X-linked hypophosphatemic rickets: a case report.

    PubMed

    Freudlsperger, Christian; Hoffmann, Juergen; Castrillon-Oberndorfer, Gregor; Engel, Michael

    2013-12-01

    Craniosynostosis can be gene-linked, or caused by metabolic diseases, such as rickets, which results from a deficiency or impaired metabolism of vitamin D, magnesium, phosphorus or calcium leading to hypomineralization of the bone. X-linked dominant hypophosphatemic rickets (XLHR) is the most prevalent genetic type of hypophosphatemic rickets and is caused by germ line mutations in the PHEX-gene. In XLHR, only few case reports of craniosynostosis were described. Here, we present a clinical report of an 18 months old child with XLHR and bilateral coronal and sagittal synostosis who was treated by subtotal cranial vault remodelling with fronto-orbital advancement and right-angled Z-osteotomies. As a consequence of the child's diminished bone regeneration capacity, surgery that is performed after the age of 1 year requires more extensive craniectomy, multiple osteotomies and rigid fixation for calvarial vault remodelling to prevent extensive bone defects. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  18. Clinical validation of coronal and sagittal spinal curve measurements based on three-dimensional vertebra vector parameters.

    PubMed

    Somoskeöy, Szabolcs; Tunyogi-Csapó, Miklós; Bogyó, Csaba; Illés, Tamás

    2012-10-01

    (Group 4; n=49), and above 75° (Group 5; n=22). All study subjects were examined by EOS 2D imaging, resulting in anteroposterior (AP) and lateral (LAT) full spine, orthogonal digital X-ray images, in standing position. Conventional coronal and sagittal curvature measurements including sagittal L5 vertebra wedges were determined by 3 experienced examiners, using traditional Cobb methods on EOS 2D AP and LAT images. Vertebra vector-based measurements were performed as published earlier, based on computer-assisted calculations of corresponding spinal curvature. Vertebra vectors were generated by dedicated software from sterEOS 3D spine models reconstructed from EOS 2D images by the same three examiners. Manual measurements were performed by each examiner, thrice for sterEOS 3D reconstructions and twice for vertebra vector-based measurements. Means comparison t test, Pearson bivariate correlation analysis, reliability analysis by intraclass correlation coefficients for intraobserver reproducibility and interrater reliability were performed using SPSS v16.0 software. In comparison with manual 2D methods, only small and nonsignificant differences were detectable in vertebra vector-based curvature data for coronal curves and thoracic kyphosis, whereas the found difference in L1-L5 lordosis values was shown to be strongly related to the magnitude of corresponding L5 wedge. Intraobserver reliability was excellent for both methods, and interrater reproducibility was consistently higher for vertebra vector-based methods that was also found to be unaffected by the magnitude of coronal curves or sagittal plane deviations. Vertebra vector-based angulation measurements could fully substitute conventional manual 2D measurements, with similar accuracy and higher intraobserver reliability and interrater reproducibility. Vertebra vectors represent a truly 3D solution for clear and comprehensible 3D visualization of spinal deformities while preserving crucial parametric information for

  19. Assessment of methods to extract the mid-sagittal plane from brain MR images

    NASA Astrophysics Data System (ADS)

    Kuijf, Hugo J.; Leemans, Alexander; Viergever, Max A.; Vincken, Koen L.

    2013-03-01

    Automatic detection of the mid-sagittal plane, separating both hemispheres of the brain, is useful in various applications. Several methods have been developed in the past years, applying different techniques to estimate the position of the mid-sagittal plane. These methods can be classified into three distinct classes: feature-based, global symmetry based, and local symmetry based methods. Feature-based methods use the shape or intensity of the interhemispheric fissure to extract the mid-sagittal plane. Global symmetry based methods reflect the entire image with respect to the sagittal axes and perform a rigid registration. Local symmetry based methods try to optimize a symmetry-measure in a small band covering the interhemispheric fissure. From each class, one leading method has been implemented. The methods have been evaluated on the same datasets to allow a fair comparison. Manual delineations were made by two experienced human observers. The results show that the examined methods perform similar to human observers. No significant differences were found between errors (defined as the angle and volume between planes) made by the methods and the inter-observer differences. Feature-based and local symmetry based methods have a low computation time of 1.8 and 0.5 seconds, respectively. The global symmetry based method has a higher computation time of 33.6 seconds, caused by the full 3D rigid registration. The largest errors, both by the methods and observers, are made in participants with cerebral atrophy. These participants have a widened interhemispheric fissure, allowing many plane orientations and positions to result in a valid division of the hemispheres.

  20. Preoperative and postoperative sagittal plane analysis in adult idiopathic scoliosis in patients older than 40 years of age.

    PubMed

    Sánchez-Mariscal, Felisa; Gomez-Rice, Alejandro; Rodríguez-López, Tamara; Zúñiga, Lorenzo; Pizones, Javier; Núñez-García, Ana; Izquierdo, Enrique

    2017-01-01

    Most of the papers correlate sagittal radiographic parameters with health-related quality of life (HRQOL) scores for patients with scoliosis. However, we do not know how changes in sagittal profile influence clinical outcomes after surgery in adult population operated for mainly frontal deformity. This study aimed to analyze spinal sagittal profile in a population operated on adult idiopathic scoliosis (AS) and to describe variations in sagittal parameters after surgery and the association between those variations and clinical outcomes. This is a historical cohort study. We included in this study 40 patients operated on AS, older than 40 at the time of surgery (mean age 54.9), and with more than 2-year follow-up (mean 7.4 years). Full-length free-standing radiographs, Scoliosis Research Society 22 (SRS22) and Short Form 36 (SF36) instruments, and satisfaction with outcomes were available at final follow-up. Sagittal preoperative and final follow-up radiographic parameters, radiographic correlation with HRQOL scores at final follow-up, and association between satisfaction and changes in sagittal profile were analyzed. A multivariate analysis was performed. No funds were received for this article. Preoperatively, the spinal sagittal plane tended to exhibit kyphosis. Most sagittal parameters did not improve at final follow-up with respect to preoperative values. We saw, after univariate analysis, that worse sagittal profile leads to worse HRQOL, but after multivariate analysis, only spinal tilt (ST) persisted as possible predictor for worse SRS activity scores. Frontal Cobb significantly improved. Most patients (82%) were satisfied with final outcomes. Variations in sagittal profile parameters did not differ between satisfied and dissatisfied patients. Although most sagittal plane parameters did not improve after surgery, surgical treatment in AS achieves a high satisfaction rate. Good clinical results do not correlate with improving sagittal plane parameters

  1. Evaluation of fractured condylar head along the sagittal plane: report of three cases.

    PubMed

    Rajesh Kumar, Bekal Pattathan; Rai, Kirthi Kumar; Shiva Kumar, H R; Upasi, Amarnath P; Shah, Ashwin

    2012-06-01

    There are case reports of sagittal fractures of the condylar head leading to bifid condyle. However bifid condyles maybe found in patients with no history of trauma. A split in the saggital plane of the condyle is not visible with a lateral, oblique or panaromic radiographs but only with anteriorposterior, transorbital projections or CT scan of the temperomandibular joint. The chances of condyle being split in the sagittal plane may be due to the medial pole extending beyond the condylar neck, moreover the condyle is composed of cancellous bone covered by a thin layer of cortical bone. Here we are presenting three case reports of Saggital split condyles and stress the need for inclusion of these type of fractures in the classification of condylar fractures.

  2. Sagittal Plane Knee Biomechanics and Vertical Ground Reaction Forces Are Modified Following ACL Injury Prevention Programs

    PubMed Central

    Padua, Darin A.; DiStefano, Lindsay J.

    2009-01-01

    Context: Injuries to the anterior cruciate ligament (ACL) occur because of excessive loading on the knee. ACL injury prevention programs can influence sagittal plane ACL loading factors and vertical ground reaction force (VGRF). Objective: To determine the influence of ACL injury prevention programs on sagittal plane knee biomechanics (anterior tibial shear force, knee flexion angle/moments) and VGRF. Data Sources: The PubMed database was searched for studies published between January 1988 and June 2008. Reference lists of selected articles were also reviewed. Study Selection: Studies were included that evaluated healthy participants for knee flexion angle, sagittal plane knee kinetics, or VGRF after performing a multisession training program. Two individuals reviewed all articles and determined which articles met the selection criteria. Approximately 4% of the articles fulfilled the selection criteria. Data Extraction: Data were extracted regarding each program’s duration, frequency, exercise type, population, supervision, and testing procedures. Means and variability measures were recorded to calculate effect sizes. One reviewer extracted all data and assessed study quality using PEDro (Physiotherapy Evidence Database). A second reviewer (blinded) verified all information. Results: There is moderate evidence to indicate that knee flexion angle, external knee flexion moment, and VGRF can be successfully modified by an ACL injury prevention program. Programs utilizing multiple exercises (ie, integrated training) appear to produce the most improvement, in comparison to that of single-exercise programs. Knee flexion angle was improved following integrated training (combined balance and strength exercises or combined plyometric and strength exercises). Similarly, external knee flexion moment was improved following integrated training consisting of balance, plyometric, and strength exercises. VGRF was improved when incorporating supervision with instruction and

  3. Sagittal plane spinal mobility is associated with dynamic balance ability of community-dwelling elderly people

    PubMed Central

    Takeuchi, Yahiko

    2017-01-01

    [Purpose] The purpose of this study was to clarify the correlation between the range of spinal mobility on the sagittal plane and the dynamic balance ability of elderly people living in communities. [Subjects and Methods] The persons studied were 31 healthy elderly people living in the community (16 females and 15 males). The range of mobility of the participants’ spines in the sagittal plane was measured by using a spinal mouse®. Balance ability was evaluated by using Functional reach (FR), Timed up and go (TUG), and Maximum walking speed (MWS). [Results] A significant positive correlation between the flexion range of the lumbar vertebrae and the FR distance was identified, and a significant negative correlation between the extension range of the thoracic vertebrae and the time required for TUG was also identified. In addition, a significant positive correlation between the extension range of the entire spine and MWS, was identified. [Conclusion] The result of this study have clarified that mobility of the spine in the sagittal plane is associated with dynamic balance ability, which is related to falling. PMID:28210054

  4. Knee joint passive stiffness and moment in sagittal and frontal planes markedly increase with compression.

    PubMed

    Marouane, H; Shirazi-Adl, A; Adouni, M

    2015-01-01

    Knee joints are subject to large compression forces in daily activities. Due to artefact moments and instability under large compression loads, biomechanical studies impose additional constraints to circumvent the compression position-dependency in response. To quantify the effect of compression on passive knee moment resistance and stiffness, two validated finite element models of the tibiofemoral (TF) joint, one refined with depth-dependent fibril-reinforced cartilage and the other less refined with homogeneous isotropic cartilage, are used. The unconstrained TF joint response in sagittal and frontal planes is investigated at different flexion angles (0°, 15°, 30° and 45°) up to 1800 N compression preloads. The compression is applied at a novel joint mechanical balance point (MBP) identified as a point at which the compression does not cause any coupled rotations in sagittal and frontal planes. The MBP of the unconstrained joint is located at the lateral plateau in small compressions and shifts medially towards the inter-compartmental area at larger compression forces. The compression force substantially increases the joint moment-bearing capacities and instantaneous angular rigidities in both frontal and sagittal planes. The varus-valgus laxities diminish with compression preloads despite concomitant substantial reductions in collateral ligament forces. While the angular rigidity would enhance the joint stability, the augmented passive moment resistance under compression preloads plays a role in supporting external moments and should as such be considered in the knee joint musculoskeletal models.

  5. Correlation of Dental and Skeletal Malocclusions in Sagittal Plane among Saudi Orthodontic Patients.

    PubMed

    Al-Hamlan, Nasir; Al-Eissa, Balsam; Al-Hiyasat, Ahmad S; Albalawi, Farraj S; Ahmed, Anwar E

    2015-05-01

    Whether or not the dental relationship correlates with skeletal relationship in the sagittal plane is an area of interest for orthodontic diagnosis and treatment planning. Thus, the aim of this study was to investigate the correlation of the dental malocclusion and the skeletal malocclusion in the sagittal plane among Saudi orthodontic patients. Orthodontic dental casts and cephalometric radiographs of 124 patients were investigated and analyzed. The dental casts were classified in relation to the molar relationship according to Angle's classification and to the incisal relationship according to the British Standards Institution (BSI) classification. The sagittal relation in the cephalometric radiographs was analyzed according to ANB angle and WITS appraisal. The results show that the incisal relation had a very high significant association with WITS appraisal (p = 0.0045), whereas with ANB, the association was marginally significant (p =0.0528). No significant associations were found with molar relation neither at ANB (p = 0.2075) nor at the WITS (p = 0.4794) appraisal. Significant positive correlations between ANB and WITS appraisal were found at the three incisal classification classes (class I, r = 0.73; class II, r = 0.64; class III, r = 0.75) and no significant correlation was observed in all classes with the Angle's (molar) classification. The incisal classification had a significant association with WITS appraisal, whereas with ANB the association was marginally significant. No correlation was found between Angle's (molar) classification and ANB or WITS appraisal. The incisal relation could be considered as a good indicator of the skeletal malocclusion in the sagittal plane in the orthodontic practice.

  6. Consistent detection of mid-sagittal planes for follow-up MR brain studies

    NASA Astrophysics Data System (ADS)

    Wang, Yiwen; Zhang, Li

    2008-03-01

    The mid-sagittal plane (MSP) is a commonly used anatomic landmark for standardized MR brain acquisition. In addition to the requirement of accurate detection of the MSP geometry, it is also imperative from clinical point of view to consistently prescribe scan planning for evaluation of pathology process in follow-up studies. In this work, an adaptive technique of scan planning has been developed to enforce the consistency among scans acquired at different time points from the same patient by maximizing image similarity in the proximity of MSP. The geometry parameters of the MSP of current study are optimized by simplex algorithm to achieve better similarity to the reference study. Meanwhile different similarity measures are studied and evaluated within the region of the interest of each MSP. The method is successfully tested on self-reference consistency study by manually setting the reference sagittal image. It is also tested with clinical follow-up studies of MR images acquired from 30 patients. By visual inspection, the adaptive consistency method improves the similarity to the reference images in 22 follow-up studies evidently, while the similarity to the reference images in 7 studies improves slightly. This result demonstrates the efficacy of our method on consistent detection of mid-sagittal planes for follow-up MR brain study.

  7. Differences in early sagittal plane alignment between thoracic and lumbar adolescent idiopathic scoliosis.

    PubMed

    Schlösser, Tom P C; Shah, Suken A; Reichard, Samantha J; Rogers, Kenneth; Vincken, Koen L; Castelein, René M

    2014-02-01

    It has previously been shown that rotational stability of spinal segments is reduced by posteriorly directed shear loads that are the result of gravity and muscle tone. Posterior shear loads act on those segments of the spine that are posteriorly inclined, as determined by each individual's inherited sagittal spinal profile. Accordingly, it can be inferred that certain sagittal spinal profiles are more prone to develop a rotational deformity that may lead to idiopathic scoliosis; and lumbar scoliosis, on one end of the spectrum, develops from a different sagittal spinal profile than thoracic scoliosis on the other end. To examine the role of sagittal spinopelvic alignment in the etiopathogenesis of different types of idiopathic scoliosis. Multicenter retrospective analysis of lateral radiographs of patients with small thoracic and lumbar adolescent idiopathic scoliotic curves. We included 192 adolescent idiopathic scoliosis patients with either a thoracic (n=128) or lumbar (n=64) structural curve with a Cobb angle of less than 20° were studied. Children with other spinal pathology or with more severe idiopathic scoliosis were excluded, because this disturbs their original sagittal profile. Subjects who underwent scoliosis screening and had a normal spine were included in the control cohort (n=95). Thoracic kyphosis, lumbar lordosis, T9 sagittal offset, C7 and T4 sagittal plumb lines, pelvic incidence, pelvic tilt, and sacral slope, as well as parameters describing orientation in space of each individual vertebra between C7 and L5 and length of the posteriorly inclined segment. On standardized lateral radiographs of the spine, a systematic, semi-automatic measurement of the different sagittal spinopelvic parameters was performed for each subject using in-house developed computer software. Early thoracic scoliosis showed a significantly different sagittal plane from lumbar scoliosis. Furthermore, both scoliotic curve patterns were different from controls, but in a

  8. Biomechanical Comparison of Single- and Double-Leg Jump Landings in the Sagittal and Frontal Plane

    PubMed Central

    Taylor, Jeffrey B.; Ford, Kevin R.; Nguyen, Anh-Dung; Shultz, Sandra J.

    2016-01-01

    Background: Double-leg forward or drop-jump landing activities are typically used to screen for high-risk movement strategies and to determine the success of neuromuscular injury prevention programs. However, research suggests that these tasks that occur primarily in the sagittal plane may not adequately represent the lower extremity biomechanics that occur during unilateral foot contact or non–sagittal plane movements that are characteristic of many multidirectional sports. Purpose: To examine the extent to which lower extremity biomechanics measured during a jump landing on a double leg (DL) after a sagittal plane (SAG) movement is representative of biomechanics measured during single-leg (SL) or frontal plane (FRONT) jump landing tasks. Study Design: Controlled laboratory study. Methods: Lower extremity biomechanics were measured in 15 recreationally active females (mean age [±SD], 19.4 ± 2.1 years; mean height, 163.3 ± 5.9 cm; mean weight, 61.1 ± 7.1 kg) while performing SAGDL, SAGSL, FRONTDL, and FRONTSL jump landing tasks. Repeated-measures analyses of variance examined differences in lower extremity biomechanics between the 4 tasks, and linear regressions examined the extent to which an individual’s biomechanics during SAGDL were representative of their biomechanics during SAGSL, FRONTDL, and FRONTSL. Results: Lower extremity kinematics and kinetics differed by condition, with the SAGDL task generally eliciting greater hip and knee flexion angles and lower hip and knee forces than the other tasks (P < .05). Although biomechanics during the SAGDL task were strongly associated with those during the FRONTDL task (R 2, 0.41-0.82), weaker associations were observed between SAGDL and single-leg tasks for hip kinematics (R 2, 0.03-0.25) and kinetics (R 2, 0.05-0.20) and knee abduction moments (R 2, 0.06-0.18) (P < .05). Conclusion: Standard double-leg sagittal plane jump landing tasks used to screen for ACL injury risk and the effectiveness of ACL injury

  9. [Multiplane postmortem cerebral computed angiotomography--Part II. Normal anatomy of cerebral vessels on the modified coronal, Towne and semisagittal planes].

    PubMed

    Yamamoto, Y; Satoh, T; Asari, S; Sadamoto, K

    1982-06-01

    In order to obtain a detailed knowledge of the cerebral vasculature on computed tomographic (CT) images, multiplane CT scannings on the axial, coronal, Towne and sagittal planes are required. Previous reports have concerned only the axial CT images of the cerebral vasculature, and no mention has been made about the vasculature on the coronal, Towne or sagittal images. This paper concerns the normal anatomy of the cerebral vessels on the modified coronal, Towne (half-axial) and semisagittal CT planes using 9 fresh cadavers. They received postmortem injection of contrast agents and were scanned by GE-CT/T 8800 as mentioned in Part I. Scanning planes were the modified 50-60 degrees coronal, Towne (40-45 degrees off the canthomeatal line), and the semisagittal (45 degrees toward the sagittal plane). The main vascular structures visualized on the modified coronal CT plane resembled the antero-posterior view of the carotid angiogram, and they were as follows: internal carotid arteries (supra-clinoid portion), posterior communicating arteries, anterior choroidal arteries, anterior cerebral arteries (horizontal and ascending portions, pericallosal and callosomarginal arteries and other cortical branches), middle cerebral arteries (horizontal, insular, opercular and terminal portions with identification of the angiographic Sylvian point), lenticulostriate arteries, posterior cerebral arteries, basal vein of Rosenthal (BVR), internal cerebral veins (ICV), subependymal veins which drain into BVR and ICV, choroid veins, vein of Galen, and venous sinuses. As for the demonstration of the lenticulostriate arteries or the Moyamoya vessels in clinical cases, the modified coronal plane is preferred to the axial one. On Towne plane, the vertebro-basilar arteries and the ascending portion of anterior cerebral artery were demonstrated as linear densities, which were demonstrated as spotty densities on the axial plane. On the semisagittal plane, the median or paramedian vasculatures of

  10. Modeling Localization of Amplitude-Panned Virtual Sources in Sagittal Planes

    PubMed Central

    BAUMGARTNER, ROBERT; MAJDAK, PIOTR

    2015-01-01

    Vector-base amplitude panning (VBAP) aims at creating virtual sound sources at arbitrary directions within multichannel sound reproduction systems. However, VBAP does not consistently produce listener-specific monaural spectral cues that are essential for localization of sound sources in sagittal planes, including the front-back and up-down dimensions. In order to better understand the limitations of VBAP, a functional model approximating human processing of spectro-spatial information was applied to assess accuracy in sagittal-plane localization of virtual sources created by means of VBAP. First, we evaluated VBAP applied on two loudspeakers in the median plane, and then we investigated the directional dependence of the localization accuracy in several three-dimensional loudspeaker arrangements designed in layers of constant elevation. The model predicted a strong dependence on listeners’ individual head-related transfer functions, on virtual source directions, and on loudspeaker arrangements. In general, the simulations showed a systematic degradation with increasing polar-angle span between neighboring loudspeakers. For the design of VBAP systems, predictions suggest that spans up to 40° polar angle yield a good trade-off between system complexity and localization accuracy. Special attention should be paid to the frontal region where listeners are most sensitive to deviating spectral cues. PMID:26441471

  11. Modeling sound-source localization in sagittal planes for human listeners.

    PubMed

    Baumgartner, Robert; Majdak, Piotr; Laback, Bernhard

    2014-08-01

    Monaural spectral features are important for human sound-source localization in sagittal planes, including front-back discrimination and elevation perception. These directional features result from the acoustic filtering of incoming sounds by the listener's morphology and are described by listener-specific head-related transfer functions (HRTFs). This article proposes a probabilistic, functional model of sagittal-plane localization that is based on human listeners' HRTFs. The model approximates spectral auditory processing, accounts for acoustic and non-acoustic listener specificity, allows for predictions beyond the median plane, and directly predicts psychoacoustic measures of localization performance. The predictive power of the listener-specific modeling approach was verified under various experimental conditions: The model predicted effects on localization performance of band limitation, spectral warping, non-individualized HRTFs, spectral resolution, spectral ripples, and high-frequency attenuation in speech. The functionalities of vital model components were evaluated and discussed in detail. Positive spectral gradient extraction, sensorimotor mapping, and binaural weighting of monaural spatial information were addressed in particular. Potential applications of the model include predictions of psychophysical effects, for instance, in the context of virtual acoustics or hearing assistive devices.

  12. Modeling Localization of Amplitude-Panned Virtual Sources in Sagittal Planes.

    PubMed

    Baumgartner, Robert; Majdak, Piotr

    2015-08-18

    Vector-base amplitude panning (VBAP) aims at creating virtual sound sources at arbitrary directions within multichannel sound reproduction systems. However, VBAP does not consistently produce listener-specific monaural spectral cues that are essential for localization of sound sources in sagittal planes, including the front-back and up-down dimensions. In order to better understand the limitations of VBAP, a functional model approximating human processing of spectro-spatial information was applied to assess accuracy in sagittal-plane localization of virtual sources created by means of VBAP. First, we evaluated VBAP applied on two loudspeakers in the median plane, and then we investigated the directional dependence of the localization accuracy in several three-dimensional loudspeaker arrangements designed in layers of constant elevation. The model predicted a strong dependence on listeners' individual head-related transfer functions, on virtual source directions, and on loudspeaker arrangements. In general, the simulations showed a systematic degradation with increasing polar-angle span between neighboring loudspeakers. For the design of VBAP systems, predictions suggest that spans up to 40° polar angle yield a good trade-off between system complexity and localization accuracy. Special attention should be paid to the frontal region where listeners are most sensitive to deviating spectral cues.

  13. Modeling sound-source localization in sagittal planes for human listeners

    PubMed Central

    Baumgartner, Robert; Majdak, Piotr; Laback, Bernhard

    2015-01-01

    Monaural spectral features are important for human sound-source localization in sagittal planes, including front-back discrimination and elevation perception. These directional features result from the acoustic filtering of incoming sounds by the listener’s morphology and are described by listener-specific head-related transfer functions (HRTFs). This article proposes a probabilistic, functional model of sagittal-plane localization that is based on human listeners’ HRTFs. The model approximates spectral auditory processing, accounts for acoustic and non-acoustic listener specificity, allows for predictions beyond the median plane, and directly predicts psychoacoustic measures of localization performance. The predictive power of the listener-specific modeling approach was verified under various experimental conditions: The model predicted effects on localization performance of band limitation, spectral warping, non-individualized HRTFs, spectral resolution, spectral ripples, and high-frequency attenuation in speech. The functionalities of vital model components were evaluated and discussed in detail. Positive spectral gradient extraction, sensorimotor mapping, and binaural weighting of monaural spatial information were addressed in particular. Potential applications of the model include predictions of psychophysical effects, for instance, in the context of virtual acoustics or hearing assistive devices. PMID:25096113

  14. Biomechanical comparison of 3 ankle braces with and without free rotation in the sagittal plane.

    PubMed

    Alfuth, Martin; Klein, Dieter; Koch, Raphael; Rosenbaum, Dieter

    2014-01-01

    Various designs of braces including hinged and nonhinged models are used to provide external support of the ankle. Hinged ankle braces supposedly allow almost free dorsiflexion and plantar flexion of the foot in the sagittal plane. It is unclear, however, whether this additional degree of freedom affects the stabilizing effect of the brace in the other planes of motion. To investigate the dynamic and passive stabilizing effects of 3 ankle braces, 2 hinged models that provide free plantar flexion-dorsiflexion in the sagittal plane and 1 ankle brace without a hinge. Crossover study. University Movement Analysis Laboratory. Seventeen healthy volunteers (5 women, 12 men; age = 25.4 ± 4.8 years; height = 180.3 ± 6.5 cm; body mass = 75.5 ± 10.4 kg). We dynamically induced foot inversion on a tilting platform and passively induced foot movements in 6 directions via a custom-built apparatus in 3 brace conditions and a control condition (no brace). Maximum inversion was determined dynamically using an in-shoe electrogoniometer. Passively induced maximal joint angles were measured using a torque and angle sensor. We analyzed differences among the 4 ankle-brace conditions (3 braces, 1 control) for each of the dependent variables with Friedman and post hoc tests (P < .05). Each ankle brace restricted dynamic foot-inversion movements on the tilting platform as compared with the control condition, whereas only the 2 hinged ankle braces differed from each other, with greater movement restriction caused by the Ankle X model. Passive foot inversion was reduced with all ankle braces. Passive plantar flexion was greater in the hinged models as compared with the nonhinged brace. All ankle braces showed stabilizing effects against dynamic and passive foot inversion. Differences between the hinged braces and the nonhinged brace did not appear to be clinically relevant.

  15. Biomechanical Comparison of 3 Ankle Braces With and Without Free Rotation in the Sagittal Plane

    PubMed Central

    Alfuth, Martin; Klein, Dieter; Koch, Raphael; Rosenbaum, Dieter

    2014-01-01

    Context: Various designs of braces including hinged and nonhinged models are used to provide external support of the ankle. Hinged ankle braces supposedly allow almost free dorsiflexion and plantar flexion of the foot in the sagittal plane. It is unclear, however, whether this additional degree of freedom affects the stabilizing effect of the brace in the other planes of motion. Objective: To investigate the dynamic and passive stabilizing effects of 3 ankle braces, 2 hinged models that provide free plantar flexion–dorsiflexion in the sagittal plane and 1 ankle brace without a hinge. Design: Crossover study. Setting: University Movement Analysis Laboratory. Patients or Other Participants: Seventeen healthy volunteers (5 women, 12 men; age = 25.4 ± 4.8 years; height = 180.3 ± 6.5 cm; body mass = 75.5 ± 10.4 kg). Intervention(s): We dynamically induced foot inversion on a tilting platform and passively induced foot movements in 6 directions via a custom-built apparatus in 3 brace conditions and a control condition (no brace). Main Outcome Measure(s): Maximum inversion was determined dynamically using an in-shoe electrogoniometer. Passively induced maximal joint angles were measured using a torque and angle sensor. We analyzed differences among the 4 ankle-brace conditions (3 braces, 1 control) for each of the dependent variables with Friedman and post hoc tests (P < .05). Results: Each ankle brace restricted dynamic foot-inversion movements on the tilting platform as compared with the control condition, whereas only the 2 hinged ankle braces differed from each other, with greater movement restriction caused by the Ankle X model. Passive foot inversion was reduced with all ankle braces. Passive plantar flexion was greater in the hinged models as compared with the nonhinged brace. Conclusions: All ankle braces showed stabilizing effects against dynamic and passive foot inversion. Differences between the hinged braces and the nonhinged brace did not appear to be

  16. Agreement between Fiber Optic and Optoelectronic Systems for Quantifying Sagittal Plane Spinal Curvature in Sitting

    PubMed Central

    Cloud, Beth A.; Zhao, Kristin D.; Breighner, Ryan; Giambini, Hugo; An, Kai-Nan

    2014-01-01

    Spinal posture affects how individuals function from a manual wheelchair. There is a need to directly quantify spinal posture in this population to ultimately improve function. A fiber optic system, comprised of an attached series of sensors, is promising for measuring large regions of the spine in individuals sitting in a wheelchair. The purpose of this study was to determine the agreement between fiber optic and optoelectronic systems for measuring spinal curvature, and describe the range of sagittal plane spinal curvatures in natural sitting. Able-bodied adults (n=26, 13 male) participated. Each participant assumed three sitting postures: natural, slouched (accentuated kyphosis), and extension (accentuated lordosis) sitting. Fiber optic (ShapeTape) and optoelectronic (Optotrak) systems were applied to the skin over spinous processes from S1 to C7 and used to measure sagittal plane spinal curvature. Regions of kyphosis and lordosis were identified. A Cobb angle-like method was used to quantify lordosis and kyphosis. Generalized linear model and Bland-Altman analyses were used to assess agreement. A strong correlation exists between curvature values obtained with Optotrak and ShapeTape (R2=0.98). The mean difference between Optotrak and ShapeTape for kyphosis in natural, extension, and slouched postures was 4.30° (95%LOA: −3.43-12.04°), 3.64° (95%LOA: −1.07-8.36°), and 4.02° (95%LOA: −2.80-10.84°), respectively. The mean difference for lordosis, when present, in natural and extension postures is 2.86° (95%LOA: −1.18-6.90°) and 2.55° (95%LOA: −3.38-8.48°), respectively. In natural sitting, the mean±SD of kyphosis values was 35.07± 6.75°. Lordosis was detected in 8/26 participants: 11.72±7.32°. The fiber optic and optoelectronic systems demonstrate acceptable agreement for measuring sagittal plane thoracolumbar spinal curvature. PMID:24909579

  17. Agreement between fiber optic and optoelectronic systems for quantifying sagittal plane spinal curvature in sitting.

    PubMed

    Cloud, Beth A; Zhao, Kristin D; Breighner, Ryan; Giambini, Hugo; An, Kai-Nan

    2014-07-01

    Spinal posture affects how individuals function from a manual wheelchair. There is a need to directly quantify spinal posture in this population to ultimately improve function. A fiber optic system, comprised of an attached series of sensors, is promising for measuring large regions of the spine in individuals sitting in a wheelchair. The purpose of this study was to determine the agreement between fiber optic and optoelectronic systems for measuring spinal curvature, and describe the range of sagittal plane spinal curvatures in natural sitting. Able-bodied adults (n = 26, 13 male) participated. Each participant assumed three sitting postures: natural, slouched (accentuated kyphosis), and extension (accentuated lordosis) sitting. Fiber optic (ShapeTape) and optoelectronic (Optotrak) systems were applied to the skin over spinous processes from S1 to C7 and used to measure sagittal plane spinal curvature. Regions of kyphosis and lordosis were identified. A Cobb angle-like method was used to quantify lordosis and kyphosis. Generalized linear model and Bland-Altman analyses were used to assess agreement. A strong correlation exists between curvature values obtained with Optotrak and ShapeTape (R(2) = 0.98). The mean difference between Optotrak and ShapeTape for kyphosis in natural, extension, and slouched postures was 4.30° (95% LOA: -3.43 to 12.04°), 3.64° (95% LOA: -1.07 to 8.36°), and 4.02° (95% LOA: -2.80 to 10.84°), respectively. The mean difference for lordosis, when present, in natural and extension postures was 2.86° (95% LOA: -1.18 to 6.90°) and 2.55° (95% LOA: -3.38 to 8.48°), respectively. In natural sitting, the mean ± SD of kyphosis values was 35.07 ± 6.75°. Lordosis was detected in 8/26 participants: 11.72 ± 7.32°. The fiber optic and optoelectronic systems demonstrate acceptable agreement for measuring sagittal plane thoracolumbar spinal curvature.

  18. An Experimental Study of Energy-Saving Shoes for Robot as Sagittal Plane Assistance

    NASA Astrophysics Data System (ADS)

    Minakata, Hideaki; Tadakuma, Susumu

    In this paper, we propose flexible shoe system to apply passive walking manner to ordinary humanoid biped. In this system, 2DOF (FF & FB) control scheme is used and realize walking with less ankle torque. Besides, this system is consisted as reference modification of position control system, so it can be applicable to most of walking robot even if its joint servo is black box. The effectiveness and characteristics of this system is confirmed by computer simulations and experimental result. The softness of shoe is very important parameter for energy consumption and walking stability. From the discussions of the system, it is said that sagittal plane assistance shoes reduce the energy loss due to the ankle joint friction. Finally, we confirmed the reduction of energy consumption on walking experiment, so we call this system as “energy saving shoes.”

  19. Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility.

    PubMed

    Williams, D S Blaise; Welch, Lee M

    2015-01-01

    Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females. To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners. Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05). Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (p<0.05). Flexible females (36.7±7.4º) exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01) and flexible males (30.1±9.5º, p<0.05). No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment. Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners.

  20. A dynamic finite element analysis of human foot complex in the sagittal plane during level walking.

    PubMed

    Qian, Zhihui; Ren, Lei; Ding, Yun; Hutchinson, John R; Ren, Luquan

    2013-01-01

    The objective of this study is to develop a computational framework for investigating the dynamic behavior and the internal loading conditions of the human foot complex during locomotion. A subject-specific dynamic finite element model in the sagittal plane was constructed based on anatomical structures segmented from medical CT scan images. Three-dimensional gait measurements were conducted to support and validate the model. Ankle joint forces and moment derived from gait measurements were used to drive the model. Explicit finite element simulations were conducted, covering the entire stance phase from heel-strike impact to toe-off. The predicted ground reaction forces, center of pressure, foot bone motions and plantar surface pressure showed reasonably good agreement with the gait measurement data over most of the stance phase. The prediction discrepancies can be explained by the assumptions and limitations of the model. Our analysis showed that a dynamic FE simulation can improve the prediction accuracy in the peak plantar pressures at some parts of the foot complex by 10%-33% compared to a quasi-static FE simulation. However, to simplify the costly explicit FE simulation, the proposed model is confined only to the sagittal plane and has a simplified representation of foot structure. The dynamic finite element foot model proposed in this study would provide a useful tool for future extension to a fully muscle-driven dynamic three-dimensional model with detailed representation of all major anatomical structures, in order to investigate the structural dynamics of the human foot musculoskeletal system during normal or even pathological functioning.

  1. A Dynamic Finite Element Analysis of Human Foot Complex in the Sagittal Plane during Level Walking

    PubMed Central

    Qian, Zhihui; Ren, Lei; Ding, Yun; Hutchinson, John R.; Ren, Luquan

    2013-01-01

    The objective of this study is to develop a computational framework for investigating the dynamic behavior and the internal loading conditions of the human foot complex during locomotion. A subject-specific dynamic finite element model in the sagittal plane was constructed based on anatomical structures segmented from medical CT scan images. Three-dimensional gait measurements were conducted to support and validate the model. Ankle joint forces and moment derived from gait measurements were used to drive the model. Explicit finite element simulations were conducted, covering the entire stance phase from heel-strike impact to toe-off. The predicted ground reaction forces, center of pressure, foot bone motions and plantar surface pressure showed reasonably good agreement with the gait measurement data over most of the stance phase. The prediction discrepancies can be explained by the assumptions and limitations of the model. Our analysis showed that a dynamic FE simulation can improve the prediction accuracy in the peak plantar pressures at some parts of the foot complex by 10%–33% compared to a quasi-static FE simulation. However, to simplify the costly explicit FE simulation, the proposed model is confined only to the sagittal plane and has a simplified representation of foot structure. The dynamic finite element foot model proposed in this study would provide a useful tool for future extension to a fully muscle-driven dynamic three-dimensional model with detailed representation of all major anatomical structures, in order to investigate the structural dynamics of the human foot musculoskeletal system during normal or even pathological functioning. PMID:24244500

  2. Does Knee Osteoarthritis Differentially Modulate Proprioceptive Acuity in the Frontal and Sagittal Planes of the Knee?

    PubMed Central

    Cammarata, Martha L; Schnitzer, Thomas J; Dhaher, Yasin Y

    2012-01-01

    Objective Impaired proprioception may alter joint loading and contribute to the progression of knee osteoarthritis (OA). Though frontal plane loading at the knee contributes to OA, proprioception and its modulation with OA in this direction have not been examined. The aim of this study was to assess knee proprioceptive acuity in the frontal and sagittal planes in knee OA and healthy participants. We hypothesized that proprioceptive acuity will be decreased in the OA population in both planes of movement. Methods Thirteen persons with knee OA and fourteen healthy age-matched subjects participated. Proprioceptive acuity was assessed in varus, valgus, flexion, and extension using the threshold to detection of passive movement (TDPM). Repeated measures analysis of variance was used to assess differences in TDPM between subject groups and across movement directions. Linear regression analyses were performed to assess the correlation of TDPM between and within planes of movement. Results TDPM was found to be significantly higher (P<0.05), in the knee OA group compared to the control group for all directions tested, indicating reduced proprioceptive acuity. Differences in TDPM between groups were consistent across all movement directions, with mean difference (95% CI) for valgus: 0.94° (0.20°, 1.65°), varus: 0.92° (0.18°, 1.68°), extension: 0.93° (0.19°, 1.66°), and flexion: 1.11° (0.38°, 1.85°). TDPM measures across planes of movement were only weakly correlated, especially in the OA group. Conclusions Consistent differences in TDPM between the OA and control groups across all movement directions suggest a global, not direction-specific, reduction in sensation in knee OA patients. PMID:21547895

  3. Radiographic diagnosis of sagittal plane rotational displacement in pelvic fractures: a cadaveric model and clinical case study.

    PubMed

    Shui, Xiaolong; Ying, Xiaozhou; Kong, Jianzhong; Feng, Yongzeng; Hu, Wei; Guo, Xiaoshan; Wang, Gang

    2015-08-01

    Our objective was to measure the sagittal plane rotational (flexion and extension) displacement of hemipelvis radiologically and analyze the ratio of flexion and extension displacement of unstable pelvic fractures. We used 8 cadaveric models to study the radiographic evidence of pelvic fractures in the sagittal plane. We performed pelvic osteotomy on 8 cadavers to simulate anterior and posterior pelvic ring injury. Radiological data were measured in the flexion and extension group under different angles (5°, 10°, 15°, 20°, and 25°). We retrospectively reviewed 164 patients who were diagnosed with a unilateral fracture of the pelvis. Pelvic ring displacement was identified and recorded radiographically in cadaveric models. The flexion and extension displacement of pelvic fractures was measured in terms of the vertical distance of fracture from the top of iliac crest to the pubic tubercle (CD) or from the top of iliac crest to the lowest point of ischial tuberosity (AB). Fifty-seven pelves showed flexion displacement and 15 showed extension displacement. Closed reduction including internal fixation and external fixation was successfully used in 141 cases (86.0 %). The success rates of closed reduction in flexion and extension displacement groups were 77 and 73 %, respectively, which were lower than in unstable pelvic ring fractures. The sagittal plane rotation (flexion and extension) displacement of pelvic fractures could be measured by special points and lines on the radiographs. Minimally invasive reduction should be based on clearly identified differences between the sagittal plane rotation and the vertical displacement of pelvic fractures.

  4. Comparison Between Interactive Closest Point and Procrustes Analysis for Determining the Median Sagittal Plane of Three-Dimensional Facial Data.

    PubMed

    Xiong, Yuxue; Zhao, Yijiao; Yang, Huifang; Sun, Yucun; Wang, Yong

    2016-03-01

    To compare 2 digital methods to determine median sagittal plane of three-dimensional facial data-the interactive closest point algorithm and Procrustes analysis. The three-dimensional facial data of the 30 volunteers were got by the Face Scan 3D optical sensor (3D-Shape GmbH, Erlangen, Germany), and then were input to the reverse engineering software Imageware 13.0 (Siemens, Plano, TX) and Geomagic 2012 (Cary, NC). Their mirrored data were acquired and superimposed with the original data by the methods of interactive closest points and Procrustes analysis. The median sagittal planes of the 2 methods were extracted from the original and mirrored facial data respectively, 3 asymmetry indices were measured for comparison. Differences between the facial asymmetry indices of the 2 methods were evaluated using the paired sample t-test. In terms of the 3 asymmetry indices, there were no significant differences between interactive closest points and Procrustes analysis for extracting median sagittal plane from three-dimensional facial data.(t = 0.0.060, P = 0.953 for asymmetry index (AI) 1, t = -0.926, P = 0.362 for AI 2, t = 1.1172, P = 0.0.251 for AI 3). In this evaluation of 30 subjects, the Procrustes analysis and the interactive closest point median-sagittal planes were similar in terms of the 3 asymmetry indices. Thus, Procrustes analysis and interactive closest point can both be used to abstract median sagittal plane from three-dimensional facial data.

  5. Male and female runners demonstrate different sagittal plane mechanics as a function of static hamstring flexibility

    PubMed Central

    Williams III, D. S. Blaise; Welch, Lee M.

    2015-01-01

    ABSTRACT Background: Injuries to runners are common. However, there are many potential contributing factors to injury. While lack of flexibility alone is commonly related to injury, there are clear differences in hamstring flexibility between males and females. Objective: To compare the effect of static hamstring length on sagittal plane mechanics between male and female runners. Method: Forty subjects (30.0±6.4 years) participated and were placed in one of 4 groups: flexible males (n=10), inflexible males (n=10), flexible females (n=10), and inflexible females (n=10). All subjects were free of injury at the time of data collection. Three-dimensional kinematics and kinetics were collected while subjects ran over ground across 2 force platforms. Sagittal plane joint angles and moments were calculated at the knee and hip and compared with a 2-way (sex X flexibility) ANOVA (α=0.05). Results: Males exhibited greater peak knee extension moment than females (M=2.80±0.47, F=2.48±0.52 Nm/kg*m, p=0.05) and inflexible runners exhibited greater peak knee extension moment than flexible runners (In=2.83±0.56, Fl=2.44±0.51 Nm/kg*m, p=0.01). For hip flexion at initial contact, a significant interaction existed (p<0.05). Flexible females (36.7±7.4º) exhibited more hip flexion than inflexible females (27.9±4.6º, p<0.01) and flexible males (30.1±9.5º, p<0.05). No differences existed for knee angle at initial contact, peak knee angle, peak hip angle, or peak hip moment. Conclusion: Hamstring flexibility results in different mechanical profiles in males and females. Flexibility in the hamstrings may result in decreased moments via active or passive tension. These differences may have implications for performance and injury in flexible female runners. PMID:26537812

  6. Influence of the sagittal balance of the spine on the anterior pelvic plane and on the acetabular orientation.

    PubMed

    Legaye, Jean

    2009-12-01

    The Anterior Pelvic Plane (APP), defined by the anterior superior iliac spines and the pubic tubercle, was commonly used as reference for positioning and postoperative evaluation of the orientation of the acetabular cup in total hip arthroplasty. APP was assumed to be vertical, but was not observed always so, mostly because of associated spinal diseases inducing perturbations in the harmony of the sagittal balance of the pelvi-spinal unit. Consequently a sagittal rotation of the pelvis occurs, and so a tilt of the APP which alters directly the orientation of the cup in upright position. An analysis of the APP tilt related to the sagittal balance of the spine was provided and its implication on the cup orientation. It appeared essential for an individual adjustment of the cup positioning to avoid a functional mal-position which can lead to an increased risk of dislocation and impingement.

  7. A finite element study of a lumbar motion segment subjected to pure sagittal plane moments.

    PubMed

    Shirazi-Adl, A; Ahmed, A M; Shrivastava, S C

    1986-01-01

    A nonlinear finite element program has been developed and applied to the analysis of a three-dimensional model of the lumbar L2-3 motion segment subjected to sagittal plane moments. The analysis accounts for both material and geometric nonlinearities and is based on the Updated Lagrangian approach. The disc nucleus has been considered as an incompressible inviscid fluid and the annulus as a composite of collagenous fibres embedded in a matrix of ground substance. Articulation at the facet joints has been treated as a general moving contact problem and the spinal ligaments have been modelled as a collection of nonlinear axial elements. Effects of the loss of intradiscal pressure in flexion and of facetectomy in extension have been analyzed. Comparison of the predicted gross response characteristics with available measurements indicates satisfactory agreement. In flexion relatively large intradiscal pressures are generated, while in extension negative pressures (i.e. suction) of low magnitude are predicted. The stress distribution results indicate that the load transfer path through the posterior elements of the joint in flexion is different from that in extension. In flexion the ligaments are the means of load transfer, while in extension the load is transmitted through the pedicles, laminae and articular processes. In flexion, the inner annulus fibres at the posterolateral location are subject to maximum tensile strain. It is suggested that large flexion moment in combination with other loads is a likely cause of disc prolapse commonly found at this location of the annulus.

  8. Effect of sagittal plane mechanics on ACL strain during jump landing.

    PubMed

    Bakker, Ryan; Tomescu, Sebastian; Brenneman, Elora; Hangalur, Gajendra; Laing, Andrew; Chandrashekar, Naveen

    2016-09-01

    The relationships between non-contact anterior cruciate ligament injuries and the underlying biomechanics are still unclear, despite large quantities of academic research. The purpose of this research was to study anterior cruciate ligament strain during jump landing by investigating its correlation with sagittal plane kinetic/kinematic parameters and by creating an empirical model to estimate the maximum strain. Whole-body kinematics and ground reaction forces were measured from seven subjects performing single leg jump landing and were used to drive a musculoskeletal model that estimated lower limb muscle forces. These muscle forces and kinematics were then applied on five instrumented cadaver knees using a dynamic knee simulator system. Correlation analysis revealed that higher ground reaction force, lower hip flexion angle and higher hip extension moment among others were correlated with higher peak strain (p < 0.05). Multivariate regression analyses revealed that intrinsic anatomic factors account for most of the variance in strain. Among the extrinsic variables, hip and trunk flexion angles significantly contributed to the strain. The empirical relationship developed in this study could be used to predict the relative strain between jumps of a participant and may be beneficial in developing training programs designed to reduce an athlete's risk of injury. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1636-1644, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  9. Changes in sagittal plane kinematics with treadmill familiarization to barefoot running.

    PubMed

    Moore, Isabel S; Dixon, Sharon J

    2014-10-01

    Interest in barefoot running and research on barefoot running are growing. However a methodological issue surrounding investigations is how familiar the participants are with running barefoot. The aim of the study was to assess the amount of time required for habitually shod runners to become familiar with barefoot treadmill running. Twelve female recreational runners, who were experienced treadmill users, ran barefoot on a treadmill for three bouts, each bout consisting of 10 minutes at a self-selected speed with 5 minute rest periods. Sagittal plane kinematics of the hip, knee, ankle, and foot during stance were recorded during the first and last minute of each 10-minute bout. Strong reliability (ICC > .8) was shown in most variables after 20 minutes of running. In addition, there was a general trend for the smallest standard error of mean to occur during the same period. Furthermore, there were no significant differences in any of the biomechanical variables after 20 minutes of running. Together, this suggests that familiarization was achieved between 11 and 20 minutes of running barefoot on a treadmill. Familiarization was characterized by less plantar flexion and greater knee flexion at touchdown. These results indicate that adequate familiarization should be given in future studies before gait assessment of barefoot treadmill running.

  10. Targeted Paced and Unpaced Movements in the Transverse and Sagittal Planes.

    PubMed

    Hoffmann, Errol R; Sheikh, Ilyas H

    2017-01-01

    Five experiments are reported related to control of arm movement in the sagittal and transverse planes when making paced and unpaced movements. A single group of 12 participants and the same equipment were used in the main experiments to allow comparisons across conditions. As well as the 2 different directions of movement, there were movements that were time-constrained (as in the W. D. A. Beggs & C. I. Howarth, 1971, 1972a,b paradigm) and movements that were constrained by the ending tolerance (as in Fitts' paradigm). Results showed that, for movement times as high as 900 ms, the Schmidt and Beggs and Howarth models appeared to describe the time for movements that had time constraint. Fitts' law (P. M. Fitts, 1954 ; P. M. Fitts & J. R. Peterson, 1964) applied to movements that were constrained by final accuracy. These results were independent of whether the target was in the aiming or stopping movement direction. A new interpretation of data for movements with time constraint is presented, based on the possible number of accuracy submovements available when near the target. This model suggests that the standard deviation of hits at the target is not dependent on the time spent in reaching the target region, but largely on the time remaining in order to produce final accuracy at the target.

  11. Accuracy and reliability of coronal and sagittal spinal curvature data based on patient-specific three-dimensional models created by the EOS 2D/3D imaging system.

    PubMed

    Somoskeöy, Szabolcs; Tunyogi-Csapó, Miklós; Bogyó, Csaba; Illés, Tamás

    2012-11-01

    Three-dimensional (3D) deformations of the spine are predominantly characterized by two-dimensional (2D) angulation measurements in coronal and sagittal planes, using anteroposterior and lateral X-ray images. For coronal curves, a method originally described by Cobb and for sagittal curves a modified Cobb method are most widely used in practice, and these methods have been shown to exhibit good-to-excellent reliability and reproducibility, carried out either manually or by computer-based tools. Recently, an ultralow radiation dose-integrated radioimaging solution was introduced with special software for realistic 3D visualization and parametric characterization of the spinal column. Comparison of accuracy, correlation of measurement values, intraobserver and interrater reliability of methods by conventional manual 2D and sterEOS 3D measurements in a routine clinical setting. Retrospective nonrandomized study of diagnostic X-ray images created as part of a routine clinical protocol of eligible patients examined at our clinic during a 30-month period between July 2007 and December 2009. In total, 201 individuals (170 females, 31 males; mean age, 19.88 years) including 10 healthy athletes with normal spine and patients with adolescent idiopathic scoliosis (175 cases), adult degenerative scoliosis (11 cases), and Scheuermann hyperkyphosis (5 cases). Overall range of coronal curves was between 2.4° and 117.5°. Analysis of accuracy and reliability of measurements were carried out on a group of all patients and in subgroups based on coronal plane deviation: 0° to 10° (Group 1, n=36), 10° to 25° (Group 2, n=25), 25° to 50° (Group 3, n=69), 50° to 75° (Group 4, n=49), and more than 75° (Group 5, n=22). Coronal and sagittal curvature measurements were determined by three experienced examiners, using either traditional 2D methods or automatic measurements based on sterEOS 3D reconstructions. Manual measurements were performed three times, and sterEOS 3D

  12. Changing Sagittal-Plane Landing Styles to Modulate Impact and Tibiofemoral Force Magnitude and Directions Relative to the Tibia.

    PubMed

    Shimokochi, Yohei; Ambegaonkar, Jatin P; Meyer, Eric G

    2016-09-01

    Ground reaction force (GRF) and tibiofemoral force magnitudes and directions have been shown to affect anterior cruciate ligament loading during landing. However, the kinematic and kinetic factors modifying these 2 forces during landing are unknown. To clarify the intersegmental kinematic and kinetic links underlying the alteration of the GRF and tibiofemoral force vectors secondary to changes in the sagittal-plane body position during single-legged landing. Crossover study. Laboratory. Twenty recreationally active participants (age = 23.4 ± 3.6 years, height = 171.0 ± 9.4 cm, mass = 73.3 ± 12.7 kg). Participants performed single-legged landings using 3 landing styles: self-selected landing (SSL), body leaning forward and landing on the toes (LFL), and body upright with flat-footed landing (URL). Three-dimensional kinetics and kinematics were recorded. Sagittal-plane tibial inclination and knee-flexion angles, GRF magnitude and inclination angles relative to the tibia, and proximal tibial forces at peak tibial axial forces. The URL resulted in less time to peak tibial axial forces, smaller knee-flexion angles, and greater magnitude and a more anteriorly inclined GRF vector relative to the tibia than did the SSL. These changes led to the greatest peak tibial axial and anterior shear forces in the URL among the 3 landing styles. Conversely, the LFL resulted in longer time to peak tibial axial forces, greater knee-flexion angles, and reduced magnitude and a more posteriorly inclined GRF vector relative to the tibia than the SSL. These changes in LFL resulted in the lowest peak tibial axial and largest posterior shear forces among the 3 landing styles. Sagittal-plane intersegmental kinematic and kinetic links strongly affected the magnitude and direction of GRF and tibiofemoral forces during the impact phase of single-legged landing. Therefore, improving sagittal-plane landing mechanics is important in reducing harmful magnitudes and directions of impact forces on

  13. Sagittal plane rotation center of lower lumbar spine during a dynamic weight-lifting activity.

    PubMed

    Liu, Zhan; Tsai, Tsung-Yuan; Wang, Shaobai; Wu, Minfei; Zhong, Weiye; Li, Jing-Sheng; Cha, Thomas; Wood, Kirk; Li, Guoan

    2016-02-08

    This study investigated the center of rotation (COR) of the intervertebral segments of the lower lumbar spine (L4-L5 and L5-S1 segments) in sagittal plane during a weight-lifting (3.6 kg in each hand) extension activity performed with the pelvis constrained. Seven healthy subjects were studied using a dual fluoroscopic imaging technique. Using the non-weightbearing, supine position during MRI scan as a reference, the average intervertebral flexion angles of the L4-L5 and L5-S1 were 6.6° and 5.3° at flexion position of the body, respectively, and were -1.8° and -3.5° at extension position of the body, respectively. The CORs of the lower lumbar spine were found segment-dependent and changed with the body postures. The CORs of the L4-L5 segment were at the location about 75% posterior from the anterior edge of the disc at flexion positions of the body, and moved to about 92% of the posterior portion of the disc at extension positions of the body. The CORs of the L5-S1 segment were at 95% posterior portion of the disc at flexion positions of the body, and moved outside of the posterior edge of the disc by about 12% of the disc length at extension positions of the body. These results could help understand the physiological motion characters of the lower lumbar spine. The data could also provide important insights for future improvement of artificial disc designs and surgical implantation of the discs that are aimed to reproduce normal spinal functions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Muscle contributions to whole-body sagittal plane angular momentum during walking.

    PubMed

    Neptune, R R; McGowan, C P

    2011-01-04

    Walking is a complex dynamic task that requires the regulation of whole-body angular momentum to maintain dynamic balance while performing walking subtasks such as propelling the body forward and accelerating the leg into swing. In human walking, the primary mechanism to regulate angular momentum is muscle force generation. Muscles accelerate body segments and generate ground reaction forces that alter angular momentum about the body's center-of-mass to restore and maintain dynamic stability. In addition, gravity contributes to whole-body angular momentum through its contribution to the ground reaction forces. The purpose of this study was to generate a muscle-actuated forward dynamics simulation of normal walking to quantify how individual muscles and gravity contribute to whole-body angular momentum in the sagittal plane. In early stance, the uniarticular hip and knee extensors (GMAX and VAS), biarticular hamstrings (HAM) and ankle dorsiflexors (TA) generated backward angular momentum while the ankle plantar flexors (SOL and GAS) generated forward momentum. In late stance, SOL and GAS were the primary contributors and generated angular momentum in opposite directions. SOL generated primarily forward angular momentum while GAS generated backward angular momentum. The difference between muscles was due to their relative contributions to the horizontal and vertical ground reaction forces. Gravity contributed to the body's angular momentum in early stance and to a lesser extent in late stance, which was counteracted primarily by the plantar flexors. These results may provide insight into balance and movement disorders and provide a basis for developing locomotor therapies that target specific muscle groups.

  15. Sagittal plane joint loading is related to knee flexion in osteoarthritic gait.

    PubMed

    Creaby, Mark W; Hunt, Michael A; Hinman, Rana S; Bennell, Kim L

    2013-10-01

    High mechanical loading has been consistently linked with medial tibiofemoral osteoarthritis, and is considered to play a central role in the pathogenesis of the disease. Evidence from healthy adults indicates that knee flexion kinematics may influence knee load. The purpose of this study therefore, was to investigate the association between knee flexion kinematics and indicators of joint loading during walking (peak moments and vertical ground reaction force), in individuals with medial tibiofemoral osteoarthritis. In this cross-sectional study, 89 participants with painful medial tibiofemoral osteoarthritis completed three-dimensional walking gait analysis to measure stance phase ground reaction forces, knee joint moments, and knee flexion kinematics. In stepwise regression, greater knee flexion excursion was associated with higher peak vertical ground reaction force, accounting for 10% of its variance (B=0.62 [95% CI 0.34, 0.89], P<0.001). Greater peak knee flexion was associated with a higher flexion moment, accounting for 44% of its variance (B=0.12 [95% CI 0.09, 0.15], P<0.001). No association was found between the knee adduction moment and knee flexion kinematics during walking. Our data suggest that greater knee flexion is associated with higher joint loads in the sagittal plane (i.e. a higher peak knee flexion moment). However, knee flexion kinematics were not associated with the knee adduction moment - a proxy measure of medial compartment knee load. Thus, high knee flexion should be considered an undesirable gait characteristic with respect to knee load in individuals with medial tibiofemoral osteoarthritis. © 2013.

  16. A New Model to Produce Sagittal Plane Rotational Induced Diffuse Axonal Injuries

    PubMed Central

    Davidsson, Johan; Risling, Marten

    2011-01-01

    A new in vivo animal model that produces diffuse brain injuries in sagittal plane rearward rotational acceleration has been developed. In this model, the skull of an anesthetized adult rat is tightly secured to a rotating bar. During trauma, the bar is impacted by a striker that causes the bar and the animal head to rotate rearward; the acceleration phase last 0.4 ms and is followed by a rotation at constant speed and a gentle deceleration when the bar makes contact with a padded stop. The total head angle change is less than 30°. By adjusting the air pressure in the rifle used to accelerate the striker, resulting rotational acceleration between 0.3 and 2.1 Mrad/s2 can be produced. Numerous combinations of trauma levels, post-trauma survival times, brain and serum retrieval, and tissue preparation techniques were adopted to characterize this new model. The trauma caused subdural bleedings in animals exposed to severe trauma. Staining brain tissue with β-Amyloid Precursor Protein antibodies and FD Neurosilver that detect degenerating axons revealed wide spread axonal injuries (AI) in the corpus callosum, the border between the corpus callosum and cortex and in tracts in the brain stem. The observed AIs were apparent only when the rotational acceleration level was moderate and above. On the contrary, only limited signs of contusion injuries were observed following trauma. Macrophage invasions, glial fibrillary acidic protein redistribution or hypertrophy, and blood brain barrier (BBB) changes were unusual. S100 serum analyses indicate that blood vessel and glia cell injuries occur following moderate levels of trauma despite the absence of obvious BBB injuries. We conclude that this rotational trauma model is capable of producing graded axonal injury, is repeatable and produces limited other types of traumatic brain injuries and as such is useful in the study of injury biomechanics, diagnostics, and treatment strategies following diffuse axonal injury. PMID

  17. Muscle Contributions to Whole-Body Sagittal Plane Angular Momentum during Walking

    PubMed Central

    Neptune, R.R.; McGowan, C.P.

    2010-01-01

    Walking is a complex dynamic task that requires the regulation of whole-body angular momentum to maintain dynamic balance while performing walking subtasks such as propelling the body forward and accelerating the leg into swing. In human walking, the primary mechanism to regulate angular momentum is muscle force generation. Muscles accelerate body segments and generate ground reaction forces that alter angular momentum about the body’s center-of-mass to restore and maintain dynamic stability. In addition, gravity contributes to whole-body angular momentum through its contribution to the ground reaction forces. The purpose of this study was to generate a muscle-actuated forward dynamics simulation of normal walking to quantify how individual muscles and gravity contribute to whole-body angular momentum in the sagittal plane. In early stance, the uniarticular hip and knee extensors (GMAX, VAS), biarticular hamstrings (HAM) and ankle dorsiflexors (TA) generated backward angular momentum while the ankle plantar flexors (SOL, GAS) generated forward momentum. In late stance, SOL and GAS where the primary contributors and generated angular momentum in opposite directions. SOL generated primarily forward angular momentum while GAS generated backward angular momentum. The difference between muscles was due to their relative contributions to the horizontal and vertical ground reaction forces. Gravity contributed to the body’s angular momentum in early stance and to a lesser extent in late stance, which was counteracted primarily by the plantar flexors. These results may provide insight into balance and movement disorders and provide a basis for developing locomotor therapies that target specific muscle groups. PMID:20833396

  18. The effects of changes in the sagittal plane alignment of running-specific transtibial prostheses on ground reaction forces

    PubMed Central

    Tominaga, Shuichi; Sakuraba, Keisyoku; Usui, Fumio

    2015-01-01

    [Purpose] To verify the effects of sagittal plane alignment changes in running-specific transtibial prostheses on ground reaction forces (GRFs). [Subjects and Methods] Eight transtibial amputees who used running-specific prostheses during sprinting participated. The sprint movements were recorded using a Vicon-MX system and GRF measuring devices. The experiment levels were set as regularly recommended alignment (REG; the normal alignment for the subjects) and dorsiflexion or plantar flexion from the REG. [Results] The subjects were classified into fast (100-m personal best < 12.50 s) and slow (100-m personal best ≥ 12.50 s) groups. In both groups, there were no significant differences in the center of gravity speed; further, the difference in the stance time was significant in the slow group but not in the fast group. Significant differences were observed in the step length for the fast group, whereas the stance time and step rate significantly differed in the slow group. The GRF impulse showed significant differences in the vertical and braking directions in both groups. [Conclusion] The GRFs are affected by sagittal plane alignment changes in running-specific prostheses. Moreover, our results suggest that the change in GRFs along with the altered sagittal plane alignment influenced the step length and step rate. PMID:26157216

  19. Fluoroscopic determination of the tibial insertion of the posterior cruciate ligament in the sagittal plane.

    PubMed

    Salim, Rodrigo; Salzler, Matthew J; Bergin, Mark A; Zheng, Liying; Carey, Robert E; Kfuri, Mauricio; Zhang, Xudong; Harner, Christopher D

    2015-05-01

    Currently, placement of the tibial tunnel for arthroscopic transtibial posterior cruciate ligament (PCL) reconstruction relies on a limited arthroscopic view of the native insertion or the use of intraoperative imaging. No widely accepted method exists for intraoperative determination of PCL tibial tunnel placement, and current descriptions are cumbersome. To identify the center of the PCL's anatomic tibial insertion site as a percentage of the PCL facet length on a lateral radiograph of the knee so that it may be reliably located in the sagittal plane during surgical reconstruction. Descriptive laboratory study. Twenty fresh-frozen cadaveric knees were dissected and the tibial insertions of the PCL were digitized with an optical tracing system. The digitized PCL footprints were mapped onto 3-dimensional computed tomography-acquired tibial models, and their center points were determined. A K-wire was then inserted into the center of the PCL's tibial insertion under direct visualization, a direct lateral radiograph was obtained, and the center point was measured. The center locations for both methods were defined as a percentage of PCL facet length from anterior and proximal to posterior and distal, and intraobserver and interobserver reliability was tested with 4 different observers. The average location of the PCL center on the 3-dimensional bone model method was 71.7%±5.6% along the PCL facet from anterior/proximal to posterior/distal. In the lateral radiographic method, the center of the PCL was at an average of 69.7%±4.9% of the facet length. There was no significant difference between the percentage measurements of the 2 methods (P=.13). Interobserver reliability (κ=0.57) and intraobserver reliability (κ=0.71) were moderate to strong. Locating the center of the tibial PCL insertion with fluoroscopy at a point that is 70% of the PCL tibial facet length on a true lateral radiograph is a reliable method for locating the PCL tibial insertion. The method

  20. Determination of isocentric machine parameters for inclined treatment volumes: a single solution for angled transverse or coronal treatment planes.

    PubMed

    Bradley, F L

    2001-01-01

    The derivation of the trigonometric equations necessary to calculate gantry, floor and collimator settings for a treatment plane at an angle phi to the transverse plane of the patient has been described previously. The derivation of a second set of equations to facilitate treatment in a plane at an angle phi to the coronal plane has also been described previously. This work reinterprets the geometry of inclined volumes and shows that essentially only one set of equations is required to determine the settings for treatment planes at an angle phi to either the transverse or coronal planes of the patient.

  1. Acoustic and non-acoustic factors in modeling listener-specific performance of sagittal-plane sound localization

    PubMed Central

    Majdak, Piotr; Baumgartner, Robert; Laback, Bernhard

    2014-01-01

    The ability of sound-source localization in sagittal planes (along the top-down and front-back dimension) varies considerably across listeners. The directional acoustic spectral features, described by head-related transfer functions (HRTFs), also vary considerably across listeners, a consequence of the listener-specific shape of the ears. It is not clear whether the differences in localization ability result from differences in the encoding of directional information provided by the HRTFs, i.e., an acoustic factor, or from differences in auditory processing of those cues (e.g., spectral-shape sensitivity), i.e., non-acoustic factors. We addressed this issue by analyzing the listener-specific localization ability in terms of localization performance. Directional responses to spatially distributed broadband stimuli from 18 listeners were used. A model of sagittal-plane localization was fit individually for each listener by considering the actual localization performance, the listener-specific HRTFs representing the acoustic factor, and an uncertainty parameter representing the non-acoustic factors. The model was configured to simulate the condition of complete calibration of the listener to the tested HRTFs. Listener-specifically calibrated model predictions yielded correlations of, on average, 0.93 with the actual localization performance. Then, the model parameters representing the acoustic and non-acoustic factors were systematically permuted across the listener group. While the permutation of HRTFs affected the localization performance, the permutation of listener-specific uncertainty had a substantially larger impact. Our findings suggest that across-listener variability in sagittal-plane localization ability is only marginally determined by the acoustic factor, i.e., the quality of directional cues found in typical human HRTFs. Rather, the non-acoustic factors, supposed to represent the listeners' efficiency in processing directional cues, appear to be

  2. Changing Sagittal-Plane Landing Styles to Modulate Impact and Tibiofemoral Force Magnitude and Directions Relative to the Tibia

    PubMed Central

    Shimokochi, Yohei; Ambegaonkar, Jatin P.; Meyer, Eric G.

    2016-01-01

    Context: Ground reaction force (GRF) and tibiofemoral force magnitudes and directions have been shown to affect anterior cruciate ligament loading during landing. However, the kinematic and kinetic factors modifying these 2 forces during landing are unknown. Objective: To clarify the intersegmental kinematic and kinetic links underlying the alteration of the GRF and tibiofemoral force vectors secondary to changes in the sagittal-plane body position during single-legged landing. Design: Crossover study. Setting: Laboratory. Patients or Other Participants: Twenty recreationally active participants (age = 23.4 ± 3.6 years, height = 171.0 ± 9.4 cm, mass = 73.3 ± 12.7 kg). Intervention(s): Participants performed single-legged landings using 3 landing styles: self-selected landing (SSL), body leaning forward and landing on the toes (LFL), and body upright with flat-footed landing (URL). Three-dimensional kinetics and kinematics were recorded. Main Outcome Measure(s): Sagittal-plane tibial inclination and knee-flexion angles, GRF magnitude and inclination angles relative to the tibia, and proximal tibial forces at peak tibial axial forces. Results: The URL resulted in less time to peak tibial axial forces, smaller knee-flexion angles, and greater magnitude and a more anteriorly inclined GRF vector relative to the tibia than did the SSL. These changes led to the greatest peak tibial axial and anterior shear forces in the URL among the 3 landing styles. Conversely, the LFL resulted in longer time to peak tibial axial forces, greater knee-flexion angles, and reduced magnitude and a more posteriorly inclined GRF vector relative to the tibia than the SSL. These changes in LFL resulted in the lowest peak tibial axial and largest posterior shear forces among the 3 landing styles. Conclusions: Sagittal-plane intersegmental kinematic and kinetic links strongly affected the magnitude and direction of GRF and tibiofemoral forces during the impact phase of single-legged landing

  3. Two cases of missed Salter-Harris III coronal plane fracture of the lateral femoral condyle.

    PubMed

    Sabharwal, Sanjeev; Henry, Patrick; Behrens, Fred

    2008-02-01

    Coronal plane fractures of the lateral femoral condyle can be difficult to diagnose, especially in children with open physis. Two adolescents who sustained this uncommon Salter-Harris III fracture of the knee were misdiagnosed after initial clinical examination and standard x-rays. Oblique x-rays, computed tomography, and magnetic resonance imaging were valuable in arriving at the correct diagnosis and in decision making.

  4. The effect of tibiotalar alignment on coronal plane mechanics following total ankle replacement.

    PubMed

    Grier, A Jordan; Schmitt, Abigail C; Adams, Samuel B; Queen, Robin M

    2016-07-01

    Gait mechanics following total ankle replacement (TAR) have reported improved ankle motion following surgery. However, no studies have addressed the impact of preoperative radiographic tibiotalar alignment on post-TAR gait mechanics. We therefore investigated whether preoperative tibiotalar alignment (varus, valgus, or neutral) resulted in significantly different coronal plane mechanics or ground reaction forces post-TAR. We conducted a non-randomized study of 93 consecutive end-stage ankle arthritis patients. Standard weight-bearing radiographs were obtained preoperatively to categorize patients as having neutral (±4°), varus (≥5° of varus), or valgus (≥5° of valgus) coronal plane tibiotalar alignment. All patients underwent a standard walking assessment including three-dimensional lower extremity kinetics and kinematics preoperatively, 12 and 24 months postoperatively. A significant group by time interaction was observed for the propulsive vertical ground reaction force (vGRF), coronal plane hip range of motion (ROM) and the peak hip abduction moment. The valgus group demonstrated an increase in the peak knee adduction angle and knee adduction angle at heel strike when compared to the other groups. Coronal plane ankle ROM, knee and hip angles at heel strike, and the peak hip angle exhibited significant increases across time. Peak ankle inversion moment, peak knee abduction moment and the weight acceptance vGRF also exhibited significant increases across time. Neutral ankle alignment was achieved for all patients by 2 years following TAR. Restoration of neutral ankle alignment at the time of TAR in patients with preoperative varus or valgus tibiotalar alignment resulted in biomechanics similar to those of patients with neutral preoperative tibiotalar alignment by 24-month follow-up. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. When is compensation for lumbar spinal stenosis a clinical sagittal plane deformity?

    PubMed

    Buckland, Aaron J; Vira, Shaleen; Oren, Jonathan H; Lafage, Renaud; Harris, Bradley Y; Spiegel, Matthew A; Diebo, Bassel G; Liabaud, Barthelemy; Protopsaltis, Themistocles S; Schwab, Frank J; Lafage, Virginie; Errico, Thomas J; Bendo, John A

    2016-08-01

    Degenerative lumbar stenosis (DLS) patients have been reported to lean forward in an attempt to provide neural decompression. Spinal alignment in patients with DLS may resemble that of adult spinal deformity (ASD). No previous studies have compared and contrasted the compensatory mechanisms of DLS and ASD patients. This study aimed to determine the differences in compensatory mechanisms between DLS and ASD patients with increasing severity of sagittal spinopelvic malalignment. Contrasting these compensatory mechanisms may help determine at what severity sagittal malalignment represents a clinical sagittal deformity rather than a compensation for neural compression. This is a retrospective clinical and radiological review. Baseline x-rays in patients without spinal instrumentation, with the clinical radiological and diagnoses of DLS or ASD, were assessed for patterns of spinopelvic compensatory mechanisms. Patients were stratified by sagittal vertical axis (SVA) according to the Scoliosis Research Society-Schwab [SRS-Schwab] classification. Radiographic spinopelvic parameters were measured in the DLS and ASD groups, including SVA, pelvic incidence-lumbar lordosis mismatch (PI-LL), T1 spinopelvic inclination (T1SPi), T1 pelvic angle (TPA), and pelvic tilt (PT). The two diagnosis cohorts were propensity-matched for PI and age. Each group contained 125 patients and was stratified according to the SRS-Schwab classification. Regional spinopelvic,lower limb, and global alignment parameters were assessed to identify differences in compensatory mechanisms between the two groups with differing degrees of deformity. No funding was provided by any third party in relation to carrying out this study or preparing the manuscript. With mild to moderate malalignment (SRS-Schwab groups "0," or "+" for PT, PI-LL, or SVA), DLS patients permit anterior truncal inclination and recruit posterior pelvic shift instead of pelvic tilt to maintain balance, while providing relief of neurologic

  6. Effect of posterior multilevel vertebral osteotomies on coronal and sagittal balance in fused scoliosis deformity caused by previous surgery: preliminary results.

    PubMed

    Yang, Jae Hyuk; Suh, Seung Woo; Cho, Won Tae; Hwang, Jin Ho; Hong, Jae Young; Modi, Hitesh N

    2014-10-15

    Prospective case series study. To study the effect of posterior multilevel vertebral osteotomy (posterior crack osteotomy) on coronal and sagittal balance in patients with the fusion mass over the spine caused by previous surgery. Few studies have investigated revisional scoliosis surgery with the fusion mass using osteotomy. Among patients who had a history of prior surgery for scoliosis correction and posterior fusion, those showing progression of the curve postoperatively due to nonunion, implant failure, or adding-on phenomenon were enrolled. All patients were treated using posterior crack osteotomy. For clinical evaluation, the pre- and postoperative Gross Motor Function Classification System score for walking status and the Berg balanced scale were used. For radiological evaluation, pre- and postoperative Cobb angle, and coronal and sagittal balance factors were used. Ten patients (5 males and 5 females) were enrolled. The preoperative diagnosis was neuromuscular scoliosis (3 cases), syndromic scoliosis (1 case), congenital scoliosis (5 cases), and neurofibromatosis (1 case). Osteotomies were performed at 3.3±1.3 levels on average. Pre- and postoperative Cobb angles were 70.8°±30.0° and 28.1°±20.0° (P=0.002 (0.97)), respectively. In pre- and postoperative evaluation of coronal balance, the coronal balance, clavicle angle, and T1-tilt angle were 36.8±27.1 mm and 10.4±8.5 mm, 6.7°±8.0° and 3.3°±1.5°, and 7.8°±19.0° and 4.7°±2.1°, respectively (P=0.002, 0.002, 0.002). In pre- and postoperative evaluation of sagittal balance, the spinal vertical axis, thoracic kyphosis, and lumbar alignments were 25.1±37.8 mm and 14.1±21.8 mm, 33.5°±51.1° and 29.7°±27.4°, and 45.7°±34.8° and 48.9°±23.1° (P=0.002, 0.169, 0.169). The walking and functional statuses did not change (P=0.317, 0.932). Although pulmonary and gastrointestinal complications were noted, the patients were discharged without complications. Posterior crack osteotomy can be

  7. Altered Sagittal- and Frontal-Plane Kinematics Following High-Intensity Stepping Training Versus Conventional Interventions in Subacute Stroke.

    PubMed

    Mahtani, Gordhan B; Kinnaird, Catherine R; Connolly, Mark; Holleran, Carey L; Hennessy, Patrick W; Woodward, Jane; Brazg, Gabrielle; Roth, Elliot J; Hornby, T George

    2016-09-15

    Common locomotor deficits observed in people poststroke include decreased speeds and abnormal kinematics, characterized by altered symmetry, reduced sagittal-plane joint excursions, and use of compensatory frontal-plane behaviors during the swing phase of gait. Conventional interventions utilized to mitigate these deficits often incorporate low-intensity, impairment-based or functional exercises focused on normalizing kinematics, although the efficacy of these strategies is unclear. Conversely, higher-intensity training protocols that provide only stepping practice and do not focus on kinematics have demonstrated gains in walking function, although minimal attention toward gait quality may be concerning and has not been assessed. The present study evaluated changes in spatiotemporal and joint kinematics following experimental, high-intensity stepping training compared with conventional interventions. Kinematic data were combined from a randomized controlled trial comparing experimental and conventional training and from a pilot experimental training study. Individuals with gait deficits 1 to 6 months poststroke received up to 40 sessions of either high-intensity stepping training in variable contexts or conventional lower-intensity interventions. Analyses focused on kinematic changes during graded treadmill testing before and following training. Significant improvements in speed, symmetry, and selected sagittal-plane kinematics favored experimental training over conventional training, although increases in compensatory strategies also were observed. Changes in many kinematic patterns were correlated with speed changes, and increased compensatory behaviors were associated with both stride length gains and baseline impairments. Limitations include a small sample size and use of multiple statistical comparisons. Improved speeds and selected kinematics were observed following high-intensity training, although such training also resulted in increased use of compensatory

  8. THE INFLUENCE OF HEEL HEIGHT ON SAGITTAL PLANE KNEE KINEMATICS DURING LANDING TASKS IN RECREATIONALLY ACTIVE AND ATHLETIC COLLEGIATE FEMALES

    PubMed Central

    Carcia, Christopher R.; Phelps, Amy L.; Martin, RobRoy L.; Burrows, Anne M.

    2011-01-01

    Purpose: To determine if heel height alters sagittal plane knee kinematics when landing from a forward hop or drop landing. Background: Knee angles close to extension during landing are theorized to increase ACL injury risk in female athletes. Methods: Fifty collegiate females performed two single-limb landing tasks while wearing heel lifts of three different sizes (0, 12 & 24 mm) attached to the bottom of a sneaker. Using an electrogoniometer, sagittal plane kinematics (initial contact [KAIC], peak flexion [KAPeak], and rate of excursion [RE]) were examined. Repeated measures ANOVAs were used to determine the influence of heel height on the dependent measures. Results: Forward hop task- KAIC with 0 mm, 12 mm, and 24 mm lifts were 8.88±6.5, 9.38±5.8 and 11.28±7.0, respectively. Significant differences were noted between 0 and 24 mm lift (p<.001) and 12 and 24 mm lifts (p=.003), but not between the 0 and 12 mm conditions (p=.423). KAPeak with 0 mm, 12 mm, and 24 mm lifts were 47.08±10.9, 48.18±10.3 and 48.88±9.7, respectively. A significant difference was noted between 0 and 24 mm lift (p=.004), but not between the 0 and 12 mm or 12 and 24 mm conditions (p=.071 and p=.282, respectively). The RE decreased significantly from 2128/sec±52 with the 12 mm lift to 1958/sec±55 with the 24 mm lift (p=.004). RE did not differ from 0 to 12 or 0 to 24 mm lift conditions (p=.351 and p=.086, respectively). Jump-landing task- No significant differences were found in KAIC (p=.531), KAPeak (p=.741), or the RE (p=.190) between any of the heel lift conditions. Conclusions: The addition of a 24 mm heel lift to the bottom of a sneaker significantly alters sagittal plane knee kinematics upon landing from a unilateral forward hop but not from a drop jump. PMID:21904697

  9. Grizzly bear (Ursus arctos horribilis) locomotion: forelimb joint mechanics across speed in the sagittal and frontal planes.

    PubMed

    Shine, Catherine L; Robbins, Charles T; Nelson, O Lynne; McGowan, Craig P

    2017-04-01

    The majority of terrestrial locomotion studies have focused on parasagittal motion and paid less attention to forces or movement in the frontal plane. Our previous research has shown that grizzly bears produce higher medial ground reaction forces (lateral pushing from the animal) than would be expected for an upright mammal, suggesting frontal plane movement may be an important aspect of their locomotion. To examine this, we conducted an inverse dynamics analysis in the sagittal and frontal planes, using ground reaction forces and position data from three high-speed cameras of four adult female grizzly bears. Over the speed range collected, the bears used walks, running walks and canters. The scapulohumeral joint, wrist and the limb overall absorb energy (average total net work of the forelimb joints, -0.97 W kg(-1)). The scapulohumeral joint, elbow and total net work of the forelimb joints have negative relationships with speed, resulting in more energy absorbed by the forelimb at higher speeds (running walks and canters). The net joint moment and power curves maintain similar patterns across speed as in previously studied species, suggesting grizzly bears maintain similar joint dynamics to other mammalian quadrupeds. There is no significant relationship with net work and speed at any joint in the frontal plane. The total net work of the forelimb joints in the frontal plane was not significantly different from zero, suggesting that, despite the high medial ground reaction forces, the forelimb acts as a strut in that plane. © 2017. Published by The Company of Biologists Ltd.

  10. Spatial changes of the chin in the vertical and sagittal planes after superior repositioning of the maxilla.

    PubMed

    Arabion, Hamidreza; Tabrizi, Reza; Fattahi, Hamidreza; Khaghaninezhad, Mohammadsaleh; Bahramnia, Fatemeh

    2015-05-01

    The mandible autorotates after maxillary superior repositioning. The aim of this study was to address the changes in chin position in the vertical and sagittal planes after maxillary superior repositioning. This cross-sectional study assessed participants who had class I occlusion with vertical maxillary excess and underwent maxillary superior repositioning. Two lateral cephalograms were taken in central occlusion and natural head position. The amount of maxillary superior repositioning was documented for every participant according to lateral cephalometric indices. The distance between the most prominent point of the chin and a perpendicular line from N to the Frankfort line was used to determine the sagittal changes of the chin before and after surgery. The distance from the N point to Me was used to assess the vertical changes of the chin before and after operation. The Pearson correlation test was used to determine the correlation between the amount of maxillary superior repositioning and the vertical and horizontal changes of the chin. The linear regression model was applied to predict the changes of the chin (dependent factor) according to the vertical change of the maxilla (predictive factor). The occlusal plane angle change, mandibular length, and mandibular plane angle were considered as variable factors. Twenty participants were studied. Analysis of the data demonstrated a significant correlation between the maxillary superior repositioning (predictive factor) and the horizontal and vertical changes of the chin. For every 1  mm of vertical change in the maxilla, the chin could be expected to move 0.21  mm horizontally. For a standard deviation increase of 1 in the maxillary position, the chin advanced by 0.753 of the standard deviation (β = 0.753). For every 1-mm change of the maxilla vertically, it could be estimated that the chin moved 0.71  mm vertically when the amount of maxillary impaction was 8  mm or less. For an increase in standard

  11. A direct in vivo measurement of the three-dimensional orientation of the occlusal plane and of the sagittal discrepancy of the jaws.

    PubMed

    Ferrario, Virgilio F.; Sforza, Chiarella; Serrao, Graziano; Ciusa, Veronica

    2000-02-01

    The aim of the present investigation was to three dimensionally assess craniofacial relationships in vivo. Specifically, by using a non-invasive direct technique, the following measurements were made: 1) natural head position relative to the ground; 2) orientation of the occlusal plane relative to the subject's intrinsic facial planes; and 3) anteroposterior discrepancy of the dental bases, taking into consideration all the facial hard- and soft-tissue structures. Several dental and soft-tissue facial landmarks were directly digitized from 24 adult healthy volunteers with Angle Class I occlusions by means of an electromagnetic three-dimensional computerized digitizer. In natural head position, the three-dimensional orientation of Camper's, occlusal, and mandibular planes were measured along with the anteroposterior maxillo-mandibular discrepancies. In the frontal plane projection, all the measured planes appeared about horizontal. In the lateral plane projection, on average, Camper's plane deviated from the true horizontal by approximately 18 degrees (in a 'head flexed' direction). The occlusal plane deviated from the same horizontal by about 14 degrees, while the mandibular plane had a steeper inclination (about 30 degrees ); both planes were significantly correlated to Camper's plane. The measurements of anteroposterior jaw discrepancy revealed a wide range of sagittal relationships in the analyzed subjects. The method was found to be repeatable and fast. This direct three-dimensional in vivo assessment of the orientation of occlusal plane relative to the other facial planes could allow for a more comprehensive analysis of maxillo-mandibular sagittal discrepancies.

  12. An evaluation of two methods used to determine the centre of gravity of a cadaver head in the sagittal plane.

    PubMed

    Preston, C B; Evans, W G; Rumbak, A

    1996-12-01

    A suitable method to locate the centre of gravity of the head is not available at present. Precise location of that centre will help in the understanding of aspects of cranial balance and what effect skeletal changes, following for example orthognathic surgery, may have on head posture. The objective of this research was to use a mechanical (empirical) method, based on accepted laws of physics, to determine the centres of gravity of cadaver heads in the sagittal plane and to compare these positions with those generated by a computer programme. The two methods located the centre of gravity in the same region but at a different position in each corresponding head. These differences were statistically significant (p < 0.01). It is likely that improved computer techniques together with modern three dimensional imaging methods will be able to locate the centre of gravity of a head in a living subject.

  13. Fast, Accurate and Precise Mid-Sagittal Plane Location in 3D MR Images of the Brain

    NASA Astrophysics Data System (ADS)

    Bergo, Felipe P. G.; Falcão, Alexandre X.; Yasuda, Clarissa L.; Ruppert, Guilherme C. S.

    Extraction of the mid-sagittal plane (MSP) is a key step for brain image registration and asymmetry analysis. We present a fast MSP extraction method for 3D MR images, based on automatic segmentation of the brain and on heuristic maximization of the cerebro-spinal fluid within the MSP. The method is robust to severe anatomical asymmetries between the hemispheres, caused by surgical procedures and lesions. The method is also accurate with respect to MSP delineations done by a specialist. The method was evaluated on 64 MR images (36 pathological, 20 healthy, 8 synthetic), and it found a precise and accurate approximation of the MSP in all of them with a mean time of 60.0 seconds per image, mean angular variation within a same image (precision) of 1.26o and mean angular difference from specialist delineations (accuracy) of 1.64o.

  14. Diagonal movement of the upper limb produces greater adaptive plasticity than sagittal plane flexion in the shoulder.

    PubMed

    Moreira, Rayele; Lial, Lysnara; Teles Monteiro, Maria Gabriela; Aragão, Alice; Santos David, Lorena; Coertjens, Marcelo; Silva-Júnior, Fernando L; Dias, Gildário; Velasques, Bruna; Ribeiro, Pedro; Teixeira, Silmar Silva; Bastos, Victor Hugo

    2017-03-16

    The motor rehabilitation is based on exercises that involve various joints and muscle groups. One such treatment method is Proprioceptive Neuromuscular Facilitation (PNF), which involves diagonal movements simulating many activities of daily living. The objective of this study was to investigate the differences between PNF and shoulder flexion movements performed without the diagonal component (i.e., only in the sagittal plane) using beta band absolute power as a measure of plasticity. The study included 30 volunteers randomized into three groups (control, PNF, and FLEX), with electroencephalographic signals captured before and after the performance of the task. The PNF group showed an increase in beta band absolute power in both hemispheres, indicating greater plasticity than that seen in the FLEX group. Therefore, PNF seems to be capable of promoting cortical adaptations that lead to the recruitment of both hemispheres, thus influencing cortical organization in more complex tasks. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Sagittal plane hip motion reversals during walking are associated with disease severity and poorer function in subjects with hip osteoarthritis.

    PubMed

    Foucher, Kharma C; Schlink, Bryan R; Shakoor, Najia; Wimmer, Markus A

    2012-05-11

    A midstance reversal of sagittal plane hip motion during walking, or motion discontinuity (MD), has previously been observed in subjects with endstage hip osteoarthritis (OA) and in patients with femoroacetabular impingement. The goal of the present study was to evaluate whether this gait pattern is a marker of OA presence or radiographic severity by analyzing a large IRB approved motion analysis data repository. We also hypothesized that subjects with the MD would show more substantial gait impairments than those with normal hip motion. We identified 150 subjects with symptomatic unilateral hip OA and Kellgren-Lawrence OA severity data on file, and a control group of 159 asymptomatic subjects whose ages fell within 2 standard deviations of the mean OA group age. From the gait data, the MD was defined as a reversal in the slope of the hip flexion angle curve during midstance. Logistic regressions and general linear models were used to test the association between the MD and OA presence, OA severity and, other gait variables. 53% of OA subjects compared to 7.5% of controls had the MD (p<0.001); occurrence of the MD was associated with OA severity (p=0.009). Within the OA subject group, subjects with the MD had reduced dynamic range of motion, peak, extension, and internal rotation moments compared to those who did not (MANCOVA p ≤ 0.042) after controlling for walking speed. We concluded that sagittal plane motion reversals are indeed associated with OA presence and severity, and with more severe gait abnormalities in subjects with hip OA.

  16. Analysis of the Pelvic Functional Orientation in the Sagittal Plane: A Radiographic Study With EOS 2D/3D Technology.

    PubMed

    Loppini, Mattia; Longo, Umile Giuseppe; Ragucci, Pasquala; Trenti, Nicoletta; Balzarini, Luca; Grappiolo, Guido

    2017-03-01

    We investigated the relationship between pelvic incidence (PI) with anterior pelvic plane angle (APPA), pelvic tilt (PT) angle, and sacral slope (SS) in standing and sitting positions to identify the best parameter expressing the pelvic functional orientation in the sagittal plane. We enrolled 109 consecutive patients (M:F = 43:66) eligible for a primary total hip arthroplasty (THA) with an average age of 63.4 years (15-85). EOS 2D/3D radiography was performed in standing and sitting positions before THA to evaluate the functional pelvic orientation. 3D images took into account the patient-specific sagittal balance measuring APPA, PT, SS, and PI. In standing position, functional parameters measured 5° ± 7.1 for APPA, 11° ± 8.3 for PT, 43° ± 8.5 for SS, and 53° ± 10.9 for PI. In sitting position, they were -18° ± 10.4 for APPA, 34° ± 11.8 for PT, 20° ± 12.6 for SS, and 54° ± 10.9 for PI. There was no significant difference between men and women in terms of the functional parameters in both positions. No relationship was found between APPA and PI in both positions. SS correlated with PI in standing (r = 0.66; P < .0001; R(2) = 0.44) and sitting (r = 0.51; P < .0001; R(2) = 0.26). PT correlated with PI in standing (r = 0.65; P < .0001; R(2) = 0.42) and sitting (r = 0.38; P < .0001; R(2) = 0.14). SS shows the highest correlation with functional pelvic tilt. The study suggests that adjustments in acetabular anteversion during primary THA should be based on SS. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Three-dimensional imaging of the uterus: The value of the coronal plane

    PubMed Central

    Wong, Lufee; White, Nikki; Ramkrishna, Jayshree; Júnior, Edward Araujo; Meagher, Simon; Costa, Fabricio Da Silva

    2015-01-01

    Advent in three-dimensional (3D) imaging technology has seen 3D ultrasound establish itself as a useful adjunct complementary to traditional two-dimensional imaging of the female pelvis. This advantage largely arises from its ability to reconstruct the coronal plane of the uterus, which allows further delineation of many gynecological disorders. 3D imaging of the uterus is now the preferred imaging modality for assessing congenital uterine anomalies and intrauterine device localization. Newer indications include the diagnosis of adenomyosis. It can also add invaluable information to delineate other endometrial and myometrial pathology such as fibroids and endometrial polyps. PMID:26753063

  18. Comparing inclined locomotion in a ground-living and a climbing ant species: sagittal plane kinematics.

    PubMed

    Weihmann, Tom; Blickhan, Reinhard

    2009-11-01

    Formicine ants are able to detect slopes in the substrates they crawl on. It was assumed that hair fields between the main segments of the body and between the proximal leg segments contribute to graviception which triggers a change of posture in response to substrate slopes. The sagittal kinematics of two ant species were investigated and compared on different slopes. Cataglyphis fortis, a North African desert ant, is well known for its extraordinary sense of orientation in texturally almost uniform habitats, while Formica pratensis, a common central-European species, primarily uses landmarks and pheromone traces for orientation. A comparison of these two species reveals differences in postural adaptations during inclined locomotion. Only minor slope-dependent angular adjustments were observed. The largest is a 25 degrees head rotation for Cataglyphis, even if the slope is changed by 150 degrees, suggesting dramatic changes in the field of vision. The trunk's pitch adjustment towards the increasing slope is low in both species. On all slopes Cataglyphis achieves higher running speeds than Formica and displays greater slope-dependent variation in body height. This indicates different strategies for coping with changing slopes. These specific aspects have to be reflected in the ants' respective mode of slope perception.

  19. 3-Dimensional shear wave elastography of breast lesions: Added value of color patterns with emphasis on crater sign of coronal plane.

    PubMed

    Chen, Ya-Ling; Chang, Cai; Zeng, Wei; Wang, Fen; Chen, Jia-Jian; Qu, Ning

    2016-09-01

    Color patterns of 3-dimensional (3D) shear wave elastography (SWE) is a promising method in differentiating tumoral nodules recently. This study was to evaluate the diagnostic accuracy of color patterns of 3D SWE in breast lesions, with special emphasis on coronal planes.A total of 198 consecutive women with 198 breast lesions (125 malignant and 73 benign) were included, who underwent conventional ultrasound (US), 3D B-mode, and 3D SWE before surgical excision. SWE color patterns of Views A (transverse), T (sagittal), and C (coronal) were determined. Sensitivity, specificity, and the area under the receiver operating characteristic curve (AUC) were calculated.Distribution of SWE color patterns was significantly different between malignant and benign lesions (P = 0.001). In malignant lesions, "Stiff Rim" was significantly more frequent in View C (crater sign, 60.8%) than in View A (51.2%, P = 0.013) and View T (54.1%, P = 0.035). AUC for combination of "Crater Sign" and conventional US was significantly higher than View A (0.929 vs 0.902, P = 0.004) and View T (0.929 vs 0.907, P = 0.009), and specificity significantly increased (90.4% vs 78.1%, P = 0.013) without significant change in sensitivity (85.6% vs 88.0%, P = 0.664) as compared with conventional US.In conclusion, combination of conventional US with 3D SWE color patterns significantly increased diagnostic accuracy, with "Crater Sign" in coronal plane of the highest value.

  20. Coronal plane socket stability during gait in persons with transfemoral amputation: Pilot study.

    PubMed

    Fatone, Stefania; Dillon, Michael; Stine, Rebecca; Tillges, Robert

    2014-01-01

    Little research describes which transfemoral socket design features are important for coronal plane stability, socket comfort, and gait. Our study objectives were to (1) relate socket comfort during gait to a rank order of changes in ischial containment (IC) and tissue loading and (2) compare socket comfort during gait when tissue loading and IC were systematically manipulated. Six randomly assigned socket conditions (IC and tissue compression) were assessed: (1) IC and high, (2) IC and medium, (3) IC and low, (4) no IC and high, (5) no IC and medium, and (6) no IC and low. For the six subjects in this study, there was a strong, negative relationship between comfort and changes in IC and tissue loading (rho = -0.89). With the ischium contained, tissue loading did not influence socket comfort (p = 0.47). With no IC, the socket was equally comfortable with high tissue loading (p = 0.36) but the medium (p = 0.04) and low (p = 0.02) tissue loading conditions decreased comfort significantly. Coronal plane hip moments, lateral trunk lean, step width, and walking speed were invariant to changes in IC and/or tissue loading. Our results suggest that in an IC socket, medial tissue loading mattered little in terms of comfort. Sockets without IC required high tissue loading to be as comfortable as those with IC, while suboptimal tissue loading compromised comfort.

  1. Erratum: Modeling sound-source localization in sagittal planes for human listeners [J. Acoust. Soc. Am. 136, 791-802 (2014)].

    PubMed

    Baumgartner, Robert; Majdak, Piotr; Laback, Bernhard

    2016-10-01

    This erratum concerns Eq. (4) of the original article, which defines the distance metric of the comparison process of the sagittal-plane sound localization model. The distance metric was actually implemented as a mean absolute difference but was erroneously described as a L1-norm difference.

  2. Comparing preseason frontal and sagittal plane plyometric programs on vertical jump height in high-school basketball players.

    PubMed

    King, Jeffrey A; Cipriani, Daniel J

    2010-08-01

    The primary purpose of this study was to evaluate whether frontal plane (FP) plyometrics, which are defined as plyometrics dominated with a lateral component, would produce similar increases in vertical jump height (VJH) compared to sagittal plane (SP) Plyometrics. Thirty-two junior varsity and varsity high-school basketball players participated in 6 weeks of plyometric training. Players participated in either FP or SP plyometrics for the entire study. Vertical jump height was measured on 3 occasions: preintervention (baseline), at week 3 of preparatory training, and at week 6 of training. Descriptive statistics were calculated for VJH. A 2-way analysis of variance (ANOVA) with repeated measures was used to test the difference in mean vertical jump scores using FP and SP training modalities. Results showed a significant effect over time for vertical jump (p < 0.001). Moreover, a significant time by protocol interaction was noted (p < 0.032). A 1-way ANOVA demonstrated that only the SP group demonstrated improvements over time, in VJH, p < 0.05. The FP group did not improve statistically. The data from this study suggest that FP plyometric training did not have a significant effect on VJH and significant improvement in VJH was seen in subjects participating in SP plyometrics thus reinforcing the specificity principle of training. However, coaches should implement both types of plyometrics because both training modalities can improve power and quickness among basketball players.

  3. Anterior Column Realignment has Similar Results to Pedicle Subtraction Osteotomy in Treating Adults with Sagittal Plane Deformity.

    PubMed

    Mundis, Gregory M; Turner, Jay D; Kabirian, Nima; Pawelek, Jeff; Eastlack, Robert K; Uribe, Juan; Klineberg, Eric; Bess, Shay; Ames, Chris; Deviren, Vedat; Nguyen, Stacie; Lafage, Virginie; Akbarnia, Behrooz A

    2017-09-01

    Anterior column realignment (ACR) is a minimally invasive surgical technique used for the correction of adult sagittal plane deformity. ACR is performed via a minimally invasive lateral transpsoas approach with anterior longitudinal ligament release and hyperlordotic cage placement. The objective of this study was to compare radiographic outcomes and complications in patients treated by ACR or Pedicle subtraction osteotomy (PSO). Patients who underwent ACR were matched with patients from a retrospective PSO dataset, by pelvic incidence, lumbar lordosis, and thoracic kyphosis. Inclusion criteria included pelvic incidence and lumbar lordosis mismatch > 10°, pelvic tilt > 25°, and/or C7 sagittal vertical axis >5 cm, and minimum 1-year follow-up. All (n = 17) patients who underwent ACR underwent second-stage open posterior instrumented fusion. There were no differences in baseline demographic or radiographic parameters. Both groups were found to have significant improvement from preoperative to final follow-up for lumbar lordosis, T1 spinopelvic inclination, and T1 pelvic angle. Pelvic tilt did not improve with PSO (31° to 28°) at final follow-up but did improve in ACR group (34° to 25°). No differences were identified at 3-month or final follow-up for lumbar lordosis (51° vs. 47°), pelvic tilt (25° vs. 28°), and T1 pelvic angle (23° vs. 24°). The group undergoing PSO achieved greater T1 spinopelvic inclination correction (8° vs. 1.9°). Patients who underwent ACR had significantly less estimated blood loss than patients who underwent PSO (1.6 vs. 3.6 L, respectively), but no difference in the overall major complication rates was found (35.3% vs. 41.2%, respectively). ACR achieved similar radiographic results as PSO in a matched cohort with significantly less estimated blood loss and similar overall complication rate. Copyright © 2017. Published by Elsevier Inc.

  4. Effect of Acute Alterations in Foot Strike Patterns during Running on Sagittal Plane Lower Limb Kinematics and Kinetics.

    PubMed

    Valenzuela, Kevin A; Lynn, Scott K; Mikelson, Lisa R; Noffal, Guillermo J; Judelson, Daniel A

    2015-03-01

    The purpose of this study was to determine the effect of foot strike patterns and converted foot strike patterns on lower limb kinematics and kinetics at the hip, knee, and ankle during a shod condition. Subjects were videotaped with a high speed camera while running a 5km at self-selected pace on a treadmill to determine natural foot strike pattern on day one. Preferred forefoot group (PFFG, n = 10) and preferred rear foot group (PRFG, n = 11) subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m). On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern -forefoot strike [FFS], rearfoot strike [RFS]) x 2 (Group - PFFG, PRFG) mixed model ANOVAs (p < 0.05) were run on speed, active peak vertical ground reaction force (VGRF), peak early stance and mid stance sagittal ankle moments, sagittal plane hip and knee moments, ankle dorsiflexion ROM, and sagittal plane hip and knee ROM. There were no significant interactions or between group differences for any of the measured variables. Within subject effects demonstrated that the RFS condition had significantly lower (VGRF) (RFS = 2.58 ± .21 BW, FFS = 2.71 ± 0.23 BW), dorsiflexion moment (RFS = -2.6 1± 0.61 Nm·kg(-1), FFS = -3.09 ± 0.32 Nm·kg(-1)), and dorsiflexion range of motion (RFS = 17.63 ± 3.76°, FFS = 22.10 ± 5.08°). There was also a significantly higher peak plantarflexion moment (RFS = 0.23 ± 0.11 Nm·kg(-1), FFS = 0.01 ± 0.01 Nm·kg(-1)), peak knee moment (RFS = 2.61 ± 0.54 Nm·kg(-1), FFS = 2.39 ± 0.61 Nm·kg(-1)), knee ROM (RFS = 31.72 ± 2.79°, FFS = 29.58 ± 2.97°), and hip ROM (RFS = 42.72 ± 4.03°, FFS = 41.38 ± 3.32°) as compared with the FFS condition. This research suggests

  5. Effect of Acute Alterations in Foot Strike Patterns during Running on Sagittal Plane Lower Limb Kinematics and Kinetics

    PubMed Central

    Valenzuela, Kevin A.; Lynn, Scott K.; Mikelson, Lisa R.; Noffal, Guillermo J.; Judelson, Daniel A.

    2015-01-01

    The purpose of this study was to determine the effect of foot strike patterns and converted foot strike patterns on lower limb kinematics and kinetics at the hip, knee, and ankle during a shod condition. Subjects were videotaped with a high speed camera while running a 5km at self-selected pace on a treadmill to determine natural foot strike pattern on day one. Preferred forefoot group (PFFG, n = 10) and preferred rear foot group (PRFG, n = 11) subjects were identified through slow motion video playback (n = 21, age = 22.8±2.2 years, mass = 73.1±14.5 kg, height 1.75 ± 0.10 m). On day two, subjects performed five overground run trials in both their natural and unnatural strike patterns while motion and force data were collected. Data were collected over two days so that foot strike videos could be analyzed for group placement purposes. Several 2 (Foot Strike Pattern –forefoot strike [FFS], rearfoot strike [RFS]) x 2 (Group – PFFG, PRFG) mixed model ANOVAs (p < 0.05) were run on speed, active peak vertical ground reaction force (VGRF), peak early stance and mid stance sagittal ankle moments, sagittal plane hip and knee moments, ankle dorsiflexion ROM, and sagittal plane hip and knee ROM. There were no significant interactions or between group differences for any of the measured variables. Within subject effects demonstrated that the RFS condition had significantly lower (VGRF) (RFS = 2.58 ± .21 BW, FFS = 2.71 ± 0.23 BW), dorsiflexion moment (RFS = -2.6 1± 0.61 Nm·kg-1, FFS = -3.09 ± 0.32 Nm·kg-1), and dorsiflexion range of motion (RFS = 17.63 ± 3.76°, FFS = 22.10 ± 5.08°). There was also a significantly higher peak plantarflexion moment (RFS = 0.23 ± 0.11 Nm·kg-1, FFS = 0.01 ± 0.01 Nm·kg-1), peak knee moment (RFS = 2.61 ± 0.54 Nm·kg-1, FFS = 2.39 ± 0.61 Nm·kg-1), knee ROM (RFS = 31.72 ± 2.79°, FFS = 29.58 ± 2.97°), and hip ROM (RFS = 42.72 ± 4.03°, FFS = 41.38 ± 3.32°) as compared with the FFS condition. This research suggests that

  6. Coronal plane partial articular fractures of the distal femoral condyle: current concepts in management.

    PubMed

    Arastu, M H; Kokke, M C; Duffy, P J; Korley, R E C; Buckley, R E

    2013-09-01

    Coronal plane fractures of the posterior femoral condyle, also known as Hoffa fractures, are rare. Lateral fractures are three times more common than medial fractures, although the reason for this is not clear. The exact mechanism of injury is likely to be a vertical shear force on the posterior femoral condyle with varying degrees of knee flexion. These fractures are commonly associated with high-energy trauma and are a diagnostic and surgical challenge. Hoffa fractures are often associated with inter- or supracondylar distal femoral fractures and CT scans are useful in delineating the coronal shear component, which can easily be missed. There are few recommendations in the literature regarding the surgical approach and methods of fixation that may be used for this injury. Non-operative treatment has been associated with poor outcomes. The goals of treatment are anatomical reduction of the articular surface with rigid, stable fixation to allow early mobilisation in order to restore function. A surgical approach that allows access to the posterior aspect of the femoral condyle is described and the use of postero-anterior lag screws with or without an additional buttress plate for fixation of these difficult fractures.

  7. Lumbosacral compression in maximal lifting efforts in sagittal plane with varying mechanical disadvantage in isometric and isokinetic modes.

    PubMed

    Kumar, S

    1994-12-01

    Nine normal male subjects (mean age 28.2 years and mean weight 72.6 kg) performed 20 standardized maximal effort lifting tasks. They were asked to perform stoop and squat lifts at half, three-quarters and full individual horizontal reach distances in mid-sagittal plane in isometric and isokinetic modes (fixed velocity 60 cm/s). Both stoop and squat lifts were initiated at the floor level and terminated at the individual's knuckle height keeping the horizontal distance constant throughout the lift. The isometric stoop lifts were performed with hip at 60 degrees and 90 degrees of flexion with hands at preselected reach distances. The isometric squat lifts were performed with knees at 90 degrees and 135 degrees of flexion with hands at similarly preselected reach distances. The force was measured using a Static Dynamic Strength Tester with load cell (SM 1000). The postures were recorded using a two-dimensional Peak Performance System with an event synchronizing unit. The load cell was sampled at 60 Hz and the video filming was done at 60 frames per second. The force and postural data were fed to a biomechanical model (Cheng and Kumar 1991) to extract external moment and lumbosacral compression. The strengths generated in different conditions were significantly different (p < 0.01). The strength variation ranged by up to 73% whereas the lumbosacral compression varied by only up to 15%. A high level of lumbosacral compression was maintained in all conditions.

  8. Glenoid deformity in the coronal plane correlates with humeral head changes in osteoarthritis: a radiographic analysis.

    PubMed

    Hawi, Nael; Magosch, Petra; Tauber, Mark; Lichtenberg, Sven; Martetschläger, Frank; Habermeyer, Peter

    2017-02-01

    A variety of measurements can be used to assess radiographic osteoarthritic changes of the shoulder. This study aimed to analyze the correlation between the radiographic humeral-sided Samilson and Prieto classification system and 3 different radiographic classifications describing the changes of the glenoid in the coronal plane. The study material included standardized radiographs of 50 patients with idiopathic osteoarthritis before anatomic shoulder replacement. On the basis of radiographic measurements, the cases were evaluated using the Samilson and Prieto grading system, angle β, inclination type, and critical shoulder angle by 2 independent observers. Classification measurements showed an excellent agreement between observers. Our results showed that the humeral-sided Samilson and Prieto grading system had a statistically significant good correlation with angle β (observer 1, r = 0.74; observer 2, r = 0.77; P < .05) and a statistically significant excellent correlation with the inclination type of the glenoid (observer 1, r  = 0.86; observer 2, r = 0.8; P < .05). A poor correlation to the critical shoulder angle was observed (r = -0.14, r = 0.03; P > .05). The grade of humeral-sided osteoarthritis according to Samilson and Prieto correlates with the glenoid-sided osteoarthritic changes of the glenoid in the coronal plane described by the angle β and by the inclination type of the glenoid. Higher glenoid-sided inclination is associated with higher grade of osteoarthritis in primary shoulder osteoarthritis. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  9. Reliability of cervical lordosis and global sagittal spinal balance measurements in adolescent idiopathic scoliosis.

    PubMed

    Vidal, Christophe; Ilharreborde, Brice; Azoulay, Robin; Sebag, Guy; Mazda, Keyvan

    2013-06-01

    Radiological reproducibility study. To assess intra and interobserver reliability of radiographic measurements for global sagittal balance parameters and sagittal spine curves, including cervical spine. Sagittal spine balance in adolescent idiopathic scoliosis (AIS) is a main issue and many studies have been reported, showing that coronal and sagittal deformities often involve sagittal cervical unbalance. Global sagittal balance aims to obtain a horizontal gaze and gravity line at top of hips when subject is in a static position, involving adjustment of each spine curvature in the sagittal plane. To our knowledge, no study did use a methodologically validated imaging analysis tool able to appreciate sagittal spine contours and distances in AIS and especially in the cervical region. Lateral full-spine low-dose EOS radiographs were performed in 75 patients divided in three groups (control subjects, AIS, operated AIS). Three observers digitally analyzed twice each radiograph and 11 sagittal measures were collected for each image. Reliability was assessed calculating intraobserver Pearson's r correlation coefficient, interobserver intra-class correlation coefficient (ICC) completed with a two-by-two Bland-Altman plot analysis. This measurement method has shown excellent intra and interobserver reliability in all parameters, sagittal curvatures, pelvic parameters and global sagittal balance. This study validated a simple and efficient tool in AIS sagittal contour analysis. It defined new relevant landmarks allowing to characterize cervical segmental curvatures and cervical involvement in global balance.

  10. An investigation of lower extremity energy dissipation strategies during single-leg and double-leg landing based on sagittal and frontal plane biomechanics.

    PubMed

    Yeow, Chen Hua; Lee, Peter Vee Sin; Goh, James Cho Hong

    2011-06-01

    There is limited understanding of the differences in lower extremity energy dissipation strategies between single-leg and double-leg landing maneuvers. This study sought to investigate these differences in sagittal and frontal planes, and explain the differences using kinematics and kinetics. We hypothesized that single-leg and double-leg landing maneuvers involve different lower extremity energy dissipation strategies in both planes. Ten recreational athletes were recruited and instructed to perform double-leg and single-leg landing from 0.60-m height. Force-plates and motion-capture system were used to obtain kinetics and kinematics data respectively. Joint power was taken as product of joint moment and angular velocity. Joint work was computed as integral of joint power over time, whereby negative work represented energy dissipation. In the sagittal plane, the hip and knee showed major contributions to energy dissipation during double-leg landing; the hip and ankle were the dominant energy dissipaters during single-leg landing. In the frontal plane, the hip acted as the key energy dissipater during double-leg landing; the knee contributed the most energy dissipation during single-leg landing. The knee also exhibited greater frontal plane joint ROM, moment and energy dissipation during single-leg landing than double-leg landing. Our findings indicated that different energy dissipation strategies were adopted for double-leg and single-leg landing in sagittal and frontal planes. Considering the prominent frontal plane biomechanics exhibited by the knee during single-leg landing, we expect that this maneuver may have greater likelihood of leading to traumatic knee injuries, particularly non-contact ACL injuries, compared to the double-leg landing maneuver. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. The assessment of the spinal curvatures in the sagittal plane of children using an ultrasound-based motion analysing system.

    PubMed

    Takács, Mária; Rudner, Ervin; Kovács, Attila; Orlovits, Zsanett; Kiss, Rita M

    2015-02-01

    In children's posture examinations the question often arises whether an X-ray examination is necessary or appropriate. On screening and in other cases when X-ray is contraindicated, alternative-non-invasive-examinations are available. To measure the shapes of the children's spines beside the Spinal Mouse also the Zebris ultrasound-based spine measuring instrument is accessible and nowadays commonly used. The main aim of the study is to determine the shape of the school-age children's spines in the sagittal plane with an alternative, non-invasive, radiation-free measuring method. From the results calculated from the values measured with the ultrasound-based motion analysing system-geared to age and height-the normal range of the values of kyphosis (TK), lordosis (LL) and inclination (TTI and LI) is determined. The subjects were children between the ages of 6 and 15 and between the heights of 120 and 180 cm (530 healthy, 394 with bad posture and 332 with flat feet). They were divided into groups according to their height with 5 cm long intervals. The age within the groups was irrelevant. So it is appropriate to give normal values according to height and not according to age. It was revealed that both in healthy children, in children with bad posture and in those with pes planus in the height groups, there was a significant difference between the values of males and females. On the basis of these results, normal values should be divided according to the gender. The measurement results also showed that in some of the height groups the pes planus and bad posture significantly affected the spinal curvatures.

  12. The effect of centre of mass location on sagittal plane moments around the centre of mass in trotting horses.

    PubMed

    Hobbs, Sarah Jane; Richards, Jim; Clayton, Hilary M

    2014-04-11

    The diagonal limb support pattern at trot provides pitch and roll stability, but little is known about the control of moments about the centre of mass (COM) in horses. Correct COM location is critical in the calculation of pitching moments. The objectives were to determine the effect of COM location on pitching moments in trotting horses and explore how COM location could influence balance. Kinematic (120 Hz) and GRF (4 force plates, 960 Hz) data were collected at trot from three trials of eight horses. The position of the COM was determined from the weighted summation of the segmental COMs and this was then manipulated cranially and caudally to test the model. Sagittal-plane moments around the COM were calculated for each manipulation of the model and their relationship determined using reduced major axis regression. Over the stride, the moments must sum to zero to prevent accumulation of rotational motion. This was found when the weight on the forelimbs in standing was 58.7% ± 3% (mean ± 95% C.I.), which corresponded closely to the COP ratio in standing. Moments were typically nose-up at foot strike changing to nose-down prior to midstance, and then reversing to nose-up in late stance. Mean moments were larger in the hindlimbs and more sensitive to COM location changes. Divergence of the COM from the COP creating a vertical force moment arm prior to midstance may assist the hindlimb in relation to propulsive effort. A similar effect is seen in the forelimb during single limb support.

  13. Radiographic evaluation of navicular position in the sagittal plane-correction following an extraosseous talotarsal stabilization procedure.

    PubMed

    Graham, Michael E; Jawrani, Nikhil T; Chikka, Avanthi

    2011-01-01

    The navicular drop in the sagittal plane on weight-bearing is a valid indicator of foot pronation. Dislocation of the talus on the tarsal mechanism results in hyperpronation, which can lead to excessive navicular drop. The purpose of the present study was to radiographically determine the efficacy of HyProCure(®) in realigning the navicular bone in hyperpronating feet. We hypothesized that following the placement of HyProCure(®), the navicular height would increase significantly compared to its preoperative value. Radiographs of 61 adult patients (86 feet) who received HyProCure(®) without adjunctive hindfoot or midfoot soft tissue or osseous procedures were analyzed. The distance of the navicular with respect to the cuboid was measured from the pre- and postoperative weight-bearing lateral radiographs. Additionally, we measured foot length to normalize the navicular to cuboid distance. The postoperative radiographs were taken at an average follow-up of 17 days. The mean preoperative true navicular to cuboid distance was 19 ± 6 mm as compared to a mean postoperative value of 24 ± 5 mm. The mean pre- and postoperative normalized navicular to cuboid distances were 0.098 ± 0.029 and 0.125 ± 0.027, respectively (± 1 SD). The postoperative increase in the true and normalized navicular to cuboid distance was statistically significant (p < .001). HyProCure(®) was effective in improving the anatomic alignment of the talonavicular joint by reducing excessive navicular drop. This indicates reduction of excessive abnormal pronation and stabilization of the medial column of the foot, which can also lead to reduction in the excessive forces placed on the supporting soft tissue structures. Copyright © 2011 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  14. Automated Breast Volume Scanning: Identifying 3-D Coronal Plane Imaging Features May Help Categorize Complex Cysts.

    PubMed

    Wang, Hong-Yan; Jiang, Yu-Xin; Zhu, Qing-Li; Zhang, Jing; Xiao, Meng-Su; Liu, He; Dai, Qing; Li, Jian-Chu; Sun, Qiang

    2016-03-01

    The study described here sought to identify specific ultrasound (US) automated breast volume scanning (ABVS) features that distinguish benign from malignant lesions. Medical records of 750 patients with 792 breast lesions were retrospectively reviewed. Of the 750 patients, 101 with 122 cystic lesions were included in this study, and the results ABVS results were compared with biopsy pathology results. These lesions were classified into six categories based on ABVS sonographic features: type I = simple cyst; type II = clustered cyst; type III = cystic masses with thin septa; type IV = complex cyst; type V = predominantly cystic masses; and type VI = predominantly solid masses. Comparisons were conducted between the ABVS coronal plane features of the lesions and histopathology results, and the positive predictive value (PPV) was calculated for each feature. Of the 122 lesions, 90 (73.8%) were classified as benign, and 32 (26.2%) were classified as malignant. The sensitivity, specificity and accuracy associated with ABVS features for cystic lesions were 78.1%, 74.4% and 75.4%, respectively. The 11 cases (8.9%) of type I-IV cysts were all benign. Of the 22 (18.0%) type V cysts, 16 (13.1%) were benign and 6 (4.9%) were malignant. Of the 89 (72.9%) type VI cysts, 63 (51.7%) were benign and 26 (21.3%) were malignant. The typical symptoms of malignancy on ABVS include retraction (PPV = 100%, p < 0.05), hyper-echoic halos (PPV = 85.7%, p < 0.05), microcalcification (PPV = 66.7%, p < 0.05), thick walls or thick septa (PPV = 62.5%, p < 0.05), irregular shape (PPV: 51.2%, p < 0.05), indistinct margin (PPV: 48.6%, p < 0.05) and predominantly solid masses with eccentric cystic foci (PPV = 46.8%, p < 0.05). ABVS can reveal sonographic features of the lesions along the coronal plane, which may be of benefit in the detection of malignant, predominantly cystic masses and provide high clinical values.

  15. Shoulder motor performance assessment in the sagittal plane in children with hemiplegia during single joint pointing tasks.

    PubMed

    Formica, Domenico; Petrarca, Maurizio; Rossi, Stefano; Zollo, Loredana; Guglielmelli, Eugenio; Cappa, Paolo

    2014-07-29

    Pointing is a motor task extensively used during daily life activities and it requires complex visuo-motor transformation to select the appropriate movement strategy. The study of invariant characteristics of human movements has led to several theories on how the brain solves the redundancy problem, but the application of these theories on children affected by hemiplegia is limited. This study aims at giving a quantitative assessment of the shoulder motor behaviour in children with hemiplegia during pointing tasks. Eight children with hemiplegia were involved in the study and were asked to perform movements on the sagittal plane with both arms, at low and high speed. Subject movements were recorded using an optoelectronic system; a 4-DOF model of children arm has been developed to calculate kinematic and dynamic variables. A set of evaluation indexes has been extracted in order to quantitatively assess whether and how children modify their motor control strategies when perform movements with the more affected or less affected arm. In low speed movements, no differences can be seen in terms of movement duration and peak velocity between the More Affected arm (MA) and the Less Affected arm (LA), as well as in the main characteristics of movement kinematics and dynamics. As regards fast movements, remarkable differences in terms of strategies of motor control can be observed: while movements with LA did not show any significant difference in Dimensionless Jerk Index (JI) and Dimensionless Torque-change Cost index (TC) between the elevation and lowering phases, suggesting that motor control optimization is similar for movements performed with or against gravity, movements with MA showed a statistically significant increase of both JI and TC during lowering phase. Results suggest the presence of a different control strategy for fast movements in particular during lowering phase. Results suggest that motor control is not able to optimize Jerk and Torque-change cost

  16. The Effects of Frontal- and Sagittal-Plane Plyometrics on Change-of-Direction Speed and Power in Adolescent Female Basketball Players.

    PubMed

    McCormick, Brian T; Hannon, James C; Newton, Maria; Shultz, Barry; Detling, Nicole; Young, Warren B

    2016-01-01

    Plyometrics is a popular training modality for basketball players to improve power and change-of-direction speed. Most plyometric training has used sagittal-plane exercises, but improvements in change-of-direction speed have been greater in multi-direction programs. To determine the benefits of a 6-wk frontal-plane plyometric (FPP) training program compared with a 6-wk sagittal-plane plyometric (SPP) training program with regard to power and change-of-direction speed. Fourteen female varsity high school basketball players participated in the study. Multiple 2 × 2 repeated-measures ANOVAs were used to determine differences for the FPP and SPP groups from preintervention to postintervention on 4 tests of power and 2 tests of change-of-direction speed. There was a group main effect for time in all 6 tests. There was a significant group × time interaction effect in 3 of the 6 tests. The SPP improved performance of the countermovement vertical jump more than the FPP, whereas the FPP improved performance of the lateral hop (left) and lateral-shuffle test (left) more than the SPP. The standing long jump, lateral hop (right), and lateral-shuffle test (right) did not show a significant interaction effect. These results suggest that basketball players should incorporate plyometric training in all planes to improve power and change-of-direction speed.

  17. Keyhole Revascularization for Treatment of Coronal Plane Fracture of the Lunate in Kienböck Disease.

    PubMed

    Havulinna, Jouni; Jokihaara, Jarkko; Paavilainen, Pasi; Leppänen, Olli V

    2016-11-01

    Coronal plane fracture of lunate in Kienböck disease is a challenging problem with no proven treatment. We present a technique for the treatment. A vascularized bone graft from the distal radius employing the fourth and fifth extracompartmental artery pedicles is used as a mechanical support in order to enable fracture union. The technical pearls and pitfalls are described and a clinical case is presented.

  18. A new radiographic method for evaluation of the position of the carpus in the coronal plane: results in normal subjects.

    PubMed

    Aufauvre, B; Herzberg, G; Garret, J; Berthonneaud, E; Dimnet, J

    1999-01-01

    The methods used to quantify pathological variations of the position of the carpus in the coronal plane, mainly ulnar translation of the carpus from trauma or rheumatoid disease, are often difficult to use in arthritic or postsurgical wrists; moreover, they require the measurement of the whole length of the third metacarpal. The aim of this study was to determine a reliable and easy-to-use index to analyse the position of the carpus in the coronal plane. One hundred PA X-rays of normal wrists were studied, of which 56 presented with a medial hamate facet of the lunate. An index of position of the carpus in the coronal plane is defined as the ratio of orthogonal distances from [1] the most medial point of the distal radius and [2] the most medial point of the capitate to the long axis of the radius: its mean value being 1.06 (+/- 0.13) in this series of normal wrists. The index is influenced by the presence of a medial hamate facet of the lunate, but is not dependent on the ulnar head and radial styloid process, nor on the length of the third metacarpal. To help to define the usefulness of the index in quantifying the different types of ulnar carpal translations in clinical practice, further studies are required.

  19. Correlations between sagittal plane kinematics and landing impact force during single-leg lateral jump-landings.

    PubMed

    Aizawa, Junya; Ohji, Shunsuke; Koga, Hideyuki; Masuda, Tadashi; Yagishita, Kazuyoshi

    2016-08-01

    [Purpose] The correlations of peak vertical ground reaction force and sagittal angles during single-leg lateral jump-landing with noncontact anterior cruciate ligament injury remain unknown. This study aimed to clarify the correlations between kinematics and impact force during lateral jump-landing. [Subjects and Methods] Twenty active males were included in the analysis. A sagittal-view movie camera and force plate were time synchronized. Trunk and lower extremity sagittal angles were measured 100 ms before initial contact and at peak vertical ground reaction force. Peak vertical ground reaction force, time between initial contact and peak vertical ground reaction force, and loading rate were calculated. [Results] The mean sagittal angle was 40.7° ± 7.7° for knee flexion during the flight phase and 16.4° ± 6.3° for pelvic anterior inclination during the landing phase. The mean peak vertical ground reaction force was four times the body weight. The median time to peak vertical ground reaction force was 63.8 ms. The knee flexion during the flight phase and pelvic anterior inclination angles during the landing phase were related to the peak vertical ground reaction force. [Conclusion] Increasing knee flexion and decreasing pelvic anterior inclination might reduce the impact during single-leg lateral jump-landing.

  20. Correlations between sagittal plane kinematics and landing impact force during single-leg lateral jump-landings

    PubMed Central

    Aizawa, Junya; Ohji, Shunsuke; Koga, Hideyuki; Masuda, Tadashi; Yagishita, Kazuyoshi

    2016-01-01

    [Purpose] The correlations of peak vertical ground reaction force and sagittal angles during single-leg lateral jump-landing with noncontact anterior cruciate ligament injury remain unknown. This study aimed to clarify the correlations between kinematics and impact force during lateral jump-landing. [Subjects and Methods] Twenty active males were included in the analysis. A sagittal-view movie camera and force plate were time synchronized. Trunk and lower extremity sagittal angles were measured 100 ms before initial contact and at peak vertical ground reaction force. Peak vertical ground reaction force, time between initial contact and peak vertical ground reaction force, and loading rate were calculated. [Results] The mean sagittal angle was 40.7° ± 7.7° for knee flexion during the flight phase and 16.4° ± 6.3° for pelvic anterior inclination during the landing phase. The mean peak vertical ground reaction force was four times the body weight. The median time to peak vertical ground reaction force was 63.8 ms. The knee flexion during the flight phase and pelvic anterior inclination angles during the landing phase were related to the peak vertical ground reaction force. [Conclusion] Increasing knee flexion and decreasing pelvic anterior inclination might reduce the impact during single-leg lateral jump-landing. PMID:27630422

  1. The pedicle-facet angle and tropism in the sagittal plane in degenerative spondylolisthesis: a computed tomography study using multiplanar reformations techniques.

    PubMed

    Gao, Fei; Hou, Dailun; Zhao, Bin; Sun, Xiaoli; Sun, Haitao; Li, Ning; Guo, Lijun; Liu, Cheng

    2012-04-01

    A case-control study. To analyze the facet joint orientation in the sagittal plane [pedicle-facet angle (P-F angle)] and facet tropism, and clarify the relationship between P-F angle and the amount of vertebral slipping in degenerative spondylolisthesis (DS) patients on multislice computed tomography using multiplanar reformations techniques. Some studies have indicated a correlation between DS and an increased sagittal orientation of the facet joints. However, the facet orientation has not been fully elucidated and it had been measured only in the transverse plane of computed tomography and magnetic resonance imaging. Although the P-F angle had been measured on the plain radiographs, accurate measurement was difficult to obtain because of the technical limitations. A total of 156 patients, who came to our hospital for low back pain and/or sciatica were divided into 2 groups. The DS group comprised of 78 patients with DS at L4-L5, and the control group comprised of 78 patients without spondylolisthesis. The P-F angle and tropism were measured in the sagittal plane on multi-slice computed tomography using multiplanar reformations techniques. The P-F angles at L4-L5 were 117.02±6.89 degrees (left), 115.95±6.02 degrees (right) in the DS group and 106.71±3.19 degrees (left), 105.58±3.07 degrees (right) in the control group, respectively (P₁<0.01, P(r)<0.01). The facet tropism at L4-L5 in the DS group was significantly increased, compared with that in the control group (P=0.004). The mean P-F angle at L4-L5 did not correlate with the amount of vertebral slipping (r=0.176, P=0.122). The P-F angle was the highest at L4-L5 both in the DS and the control group, which might explain the fact that L4 vertebra is more likely to slip forward. The P-F angle of the slipped vertebra alone was more horizontally inclined and facet tropism in the sagittal plane may relate well to DS.

  2. The effects of the sagittal plane malpositioning of the patella and concomitant quadriceps hypotrophy on the patellofemoral joint: a finite element analysis.

    PubMed

    Aksahin, Ertugrul; Kocadal, Onur; Aktekin, Cem N; Kaya, Defne; Pepe, Murad; Yılmaz, Serdar; Yuksel, H Yalcin; Bicimoglu, Ali

    2016-03-01

    Anterior knee pain is a common symptom after intramedullary nailing in tibia shaft fracture. Moreover, patellofemoral malalignment is also known to be a major reason for anterior knee pain. Patellofemoral malalignment predisposes to increased loading in patellar cartilage. In the previous study, we have demonstrated the quadriceps atrophy and patellofemoral malalignment after intramedullary nailing due to tibia shaft fracture. In this study, our aim was to clarify the effects of quadriceps atrophy and patellofemoral malalignment with the pathologic loading on the joint cartilage. Mesh models of patellofemoral joint were constructed with CT images and integrated with soft tissue components such as menisci and ligaments. Physiological and sagittal tilt models during extension and flexion at 15°, 30° and 60° were created generating eight models. All the models were applied with 137 N force to present the effects of normal loading and 115.7 N force for the simulation of quadriceps atrophy. Different degrees of loading were applied to evaluate the joint contact area and pressure value with the finite element analysis. There was increased patellofemoral contact area in patellar tilt models with respect to normal models. The similar loading patterns were diagnosed in all models at 0° and 15° knee flexion when 137 N force was applied. Higher loading values were obtained at 30° and 60° knee flexions in sagittal tilt models. Furthermore, in the sagittal tilt models, in which the quadriceps atrophy was simulated, the loadings at 30° and 60° knee flexion were higher than in the physiological ones. Sagittal malalignment of the patellofemoral joint is a new concept that results in different loading patterns in the patellofemoral joint biomechanics. This malalignment in sagittal plane leads to increased loading values on the patellofemoral joint at 30° and 60° of the knee flexions. This new concept should be kept in mind during the course of diagnosis and treatment

  3. Coronal holes near the equatorial plane and the solar wind abundance of iron

    NASA Astrophysics Data System (ADS)

    Ogilvie, K. W.; Coplan, M. A.; Yellin, K. A.

    1996-03-01

    Composition analysis of the solar wind from two equatorial coronal holes has been carried out with the Ion Composition Instrument on the ISEE-3 spacecraft. The abundances of oxygen, neon and iron were determined as coronal hole-related material flowed past the spacecraft. The results show that the edges of the hole-related flow are sharply defined with abundances closer to the abundances in the photosphere than in the slower solar wind. These results are similar to those found in flows from the southern polar coronal hole and suggest an underlying unity between the polar and equatorial regions of the sun.

  4. Acute coronal plane scaphoid fracture and scapholunate dissociation from an axial load: a case report.

    PubMed

    Shin, Alexander Y; Horton, Todd; Bishop, Allen T

    2005-03-01

    Coronal fractures of the scaphoid are rare and can be difficult to diagnose. Axial load injuries that result in a complete coronal fracture of the scaphoid associated with an acute scapholunate dissociation are exceedingly rare. In our patient the radiographic finding of wide scapholunate dissociation was obvious; however, the coronal scaphoid fracture was not recognized initially nor suspected. During surgery the coronal scaphoid fracture was identified, reduced anatomically, and fixed with a compression screw. The scapholunate ligament also was repaired. A good result was obtained with return to sports with extension of 60 degrees and flexion of 70 degrees , grip strength equal to that of the uninjured wrist, and no radiographic problems (arthrosis, avascular necrosis, nonunion).

  5. The effect of age on sagittal plane profile of the lumbar spine according to standing, supine, and various sitting positions

    PubMed Central

    2014-01-01

    Background The sagittal alignment of the spine changes depending on body posture and degenerative changes. This study aimed to observe changes in sagittal alignment of the lumbar spine with different positions (standing, supine, and various sitting postures) and to verify the effect of aging on lumbar sagittal alignment. Methods Whole-spine lateral radiographs were obtained for young volunteers (25.4 ± 2.3 years) and elderly volunteers (66.7 ± 1.7 years). Radiographs were obtained in standing, supine, and sitting (30°, 60°, and 90°) positions respectively. We compared the radiological changes in the lordotic and segmental angles in different body positions and at different ages. Upper and lower lumbar lordosis were defined according to differences in anatomical sagittal mobility and kinematic behavior. Results Lumbar lordosis was greater in a standing position (52.79° and 53.90° in young and old groups, respectively) and tended to decrease as position changed from supine to sitting. Compared with the younger group, the older group showed significantly more lumbar lordosis in supine and 60° and 90° sitting positions (P = 0.043, 0.002, 0.011). Upper lumbar lordosis in the younger group changed dynamically in all changed positions compared with the old group (P = 0.019). Lower lumbar lordosis showed a decreasing pattern in both age groups, significantly changing as position changed from 30° to 60° (P = 0.007, 0.007). Conclusions Lumbar lordosis decreases as position changes from standing to 90°sitting. The upper lumbar spine is more flexible in individuals in their twenties compared to those in their sixties. Changes in lumbar lordosis were concentrated in the lower lumbar region in the older group in sitting positions. PMID:24571953

  6. Case Presentation of Sagittal Balance.

    PubMed

    Kim, Paul K

    2016-04-01

    Sagittal balance is an important concept in spinal coronal and kyphotic deformity correction. Sagittal alignment/lumbar lordosis is increasingly recognized and discussed in terms of surgical outcomes. Positive sagittal balance can lead to development of iatrogenic kyphosis, flatback syndrome, adjacent level degeneration, and junctional kyphosis. This concept is no longer associated only with deformity. Spine surgeons have learned that sagittal alignment/lumbar lordosis is very important even in 1-level or 2-level interbody fusion procedures, and that it can be attained, maintained, or lost during any procedure, resulting in complications.

  7. [Influence of the included angle between anterior aspects of S2 and S1 vertebral bodies on pelvic inlet imaging in mid-line sagittal plane].

    PubMed

    Cai, Hong-ming; Gao, Shu-tu; Cheng, Chuan-de; Wu, Xue-jian; Wang, Wu-chao; Tang, Jin-cheng; Chang, Shou-ya; Duan, Wei-feng; Zhang, Chuan

    2014-08-01

    To analyze the influence of included angle between the anterior aspects of S2 and S vertebral bodies on pelvic inlet imaging in the pelvic midline sagittal plane. Totally 58 axial pelvic CT scans were chosen as study objects including 43 males and 15 females,with an average age of 40.7 years old (ranged,18 to 68 years old). The angles between the anterior aspects of S2 and S1, vertebral bodies and the horizontal plane on midline sagittal CT reconstruction were measured to simulate the optimal S2 and S1 inlet angles. The included angle between the anterior aspects of S2 and S1 vertebral bodies was calculated by subtrocting the S1,inlet angle from the S2 inlet angle defined as a base number. Then, the impact of the calculated included angles on the pelvic inlet imaging was analyzed. Results:The S2 inlet angles averaged (30.5±6.5) degrees; the S inlet angles averaged (25.7±5.9) degrees. The difference between them was significant (t=3.35, P=0.001). Ten patients had zero angle between the anterior aspects of S2 and S1 vertebral bodies; 14 patients had negative angle, averaged-(8.9±8.1) degrees; 34 patients had positive angle,averaged (11.8+6.4) degrees. The difference of included angle between the anterior aspects of S2 and S1 vertebral bodies leads to the difference between S1 inlet view and S2 inlet view in most cases, complicating the pelvic inlet imaging,and affecting the reliability of the application of pelvic inlet view. Utilizing the angles measured on the preoperative midlihe sagittal CT reconstruction to obatin the patient-customized S1 and S2 inlet views could accurately guide the S1 and S2 iliosacral screw insertion.

  8. Effects of follower load and rib cage on intervertebral disc pressure and sagittal plane curvature in static tests of cadaveric thoracic spines.

    PubMed

    Anderson, Dennis E; Mannen, Erin M; Sis, Hadley L; Wong, Benjamin M; Cadel, Eileen S; Friis, Elizabeth A; Bouxsein, Mary L

    2016-05-03

    The clinical relevance of mechanical testing studies of cadaveric human thoracic spines could be enhanced by using follower preload techniques, by including the intact rib cage, and by measuring thoracic intervertebral disc pressures, but studies to date have not incorporated all of these components simultaneously. Thus, this study aimed to implement a follower preload in the thoracic spine with intact rib cage, and examine the effects of follower load, rib cage stiffening and rib cage removal on intervertebral disc pressures and sagittal plane curvatures in unconstrained static conditions. Intervertebral disc pressures increased linearly with follower load magnitude. The effect of the rib cage on disc pressures in static conditions remains unclear because testing order likely confounded the results. Disc pressures compared well with previous reports in vitro, and comparison with in vivo values suggests the use of a follower load of about 400N to approximate loading in upright standing. Follower load had no effect on sagittal plane spine curvature overall, suggesting successful application of the technique, although increased flexion in the upper spine and reduced flexion in the lower spine suggest that the follower load path was not optimized. Rib cage stiffening and removal both increased overall spine flexion slightly, although with differing effects at specific spinal locations. Overall, the approaches demonstrated here will support the use of follower preloads, intact rib cage, and disc pressure measurements to enhance the clinical relevance of future studies of the thoracic spine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. EFFECTS OF FOLLOWER LOAD AND RIB CAGE ON INTERVERTEBRAL DISC PRESSURE AND SAGITTAL PLANE CURVATURE IN STATIC TESTS OF CADAVERIC THORACIC SPINES

    PubMed Central

    Anderson, Dennis E.; Mannen, Erin M.; Sis, Hadley L.; Wong, Benjamin M.; Cadel, Eileen S.; Friis, Elizabeth A.; Bouxsein, Mary L.

    2016-01-01

    The clinical relevance of mechanical testing studies of cadaveric human thoracic spines could be enhanced by using follower preload techniques, by including the intact rib cage, and by measuring thoracic intervertebral disc pressures, but studies to date have not incorporated all of these components simultaneously. Thus, this study aimed to implement a follower preload in the thoracic spine with intact rib cage, and examine the effects of follower load, rib cage stiffening and rib cage removal on intervertebral disc pressures and sagittal plane curvatures in unconstrained static conditions. Intervertebral disc pressures increased linearly with follower load magnitude. The effect of the rib cage on disc pressures in static conditions remains unclear because testing order likely confounded the results. Disc pressures compared well with previous reports in vitro, and comparison with in vivo values suggests the use of a follower load of about 400 N to approximate loading in upright standing. Follower load had no effect on sagittal plane spine curvature overall, suggesting successful application of the technique, although increased flexion in the upper spine and reduced flexion in the lower spine suggest that the follower load path was not optimized. Rib cage stiffening and removal both increased overall spine flexion slightly, although with differing effects at specific spinal locations. Overall, the approaches demonstrated here will support the use of follower preloads, intact rib cage, and disc pressure measurements to enhance the clinical relevance of future studies of the thoracic spine. PMID:26944690

  10. Effect of ankle-foot orthoses on the sagittal plane displacement of the center of mass in patients with stroke hemiplegia: a pilot study.

    PubMed

    Kobayashi, Toshiki; Leung, Aaron K L; Akazawa, Yasushi; Hutchins, Stephen W

    2012-01-01

    Ankle-foot orthoses (AFOs) have been reported to have positive effects on the temporal-spatial parameters and kinematics and kinetics of gait in patients with stroke. The center of mass (COM) may be used to represent whole body movement and energy cost in gait, and therefore COM movement would also be positively influenced with use of an appropriate AFO. To investigate the effect of AFOs on the sagittal plane displacement of the COM in patients with stroke hemiplegia. Five male subjects with stroke hemiplegia participated in this pilot study. The trajectory of the COM in the sagittal plane, gait speed, bilateral step length, step width, and bilateral stance time were analyzed while participants ambulated under 2 test conditions: with an AFO or with footwear only. The height of the 2 peaks of the vertical displacement of the COM in a gait cycle was subsequently measured and normalized to body height. Statistical analyses were conducted using a nonparametric Friedman test. Gait speed, bilateral step length, and the normalized peak height of the vertical COM trajectory during stance phase on the affected leg all revealed statistically significant increases (P < .05), and step width showed significant decreases (P < .05) under the AFO condition when compared to the footwear-only condition. An AFO may influence the vertical displacement of the COM in patients with stroke hemiplegia. The results of this pilot study therefore suggested that vertical movement of COM could potentially serve as a useful parameter to evaluate the effect of an AFO.

  11. Multiplanar Reformations in the Measurement of Renal Length on CT: Is It Plain Which Plane to Use?

    PubMed

    Lisanti, Christopher J; Oettel, David J; Reiter, Michael J; Schwope, Ryan B

    2015-10-01

    The objective of this study was to determine the accuracy of renal measurement on CT in multiple imaging planes. In this study, three board-certified radiologists retrospectively measured 110 kidneys on CT in 55 consecutive patients. Five measurement methods were used: axial, coronal single image, coronal multiimage, sagittal single image, and sagittal multiimage. The coronal database was sent to a postprocessing workstation, and each radiologist performed a maximum renal measurement using a best off-axis plane that was our reference standard. An ANOVA test with repeated measures and posthoc Bonferroni corrected t tests were performed. The mean differences (± standard error) compared with the reference standard method were as follows: axial, 7.7 ± 0.7 mm; coronal single image, 13.1 ± 1.4 mm; coronal multiimage, 6.4 ± 0.8 mm; sagittal single image, 6.4 ± 0.6 mm; and sagittal multiimage, 2.8 ± 0.3 mm. The reference standard measurement was larger (p < 0.001), whereas the coronal single-image measurement (p ≤ 0.006) was smaller than all other methods. The sagittal multiimage (p ≤ 0.005) was statistically significantly different from all other methods. There were no statistically significant differences among the axial, coronal multiimage, and sagittal single-image methods (p ≥ 0.088). The single-image coronal method is the least accurate, with an error of approximately 13 mm. The axial, multiimage coronal, and single-image sagittal methods underestimate renal size by approximately 6-8 mm. Multiimage sagittal is the most accurate method for measuring kidneys with an error of approximately 3 mm.

  12. Redefining the Boundaries of Interplanetary Coronal Mass Ejections from Observations at the Ecliptic Plane

    NASA Astrophysics Data System (ADS)

    Cid, C.; Palacios, J.; Saiz, E.; Guerrero, A.

    2016-09-01

    On 2015 January 6-7, an interplanetary coronal mass ejection (ICME) was observed at L1. This event, which can be associated with a weak and slow coronal mass ejection, allows us to discuss the differences between the boundaries of the magnetic cloud and the compositional boundaries. A fast stream from a solar coronal hole surrounding this ICME offers a unique opportunity to check the boundaries’ process definition and to explain differences between them. Using Wind and ACE data, we perform a complementary analysis involving compositional, magnetic, and kinematic observations providing relevant information regarding the evolution of the ICME as travelling away from the Sun. We propose erosion, at least at the front boundary of the ICME, as the main reason for the difference between the boundaries, and compositional signatures as the most precise diagnostic tool for the boundaries of ICMEs.

  13. Sagittal plane gait characteristics in hip osteoarthritis patients with mild to moderate symptoms compared to healthy controls: a cross-sectional study

    PubMed Central

    2012-01-01

    Background Existent biomechanical studies on hip osteoarthritic gait have primarily focused on the end stage of disease. Consequently, there is no clear consensus on which specific gait parameters are of most relevance for hip osteoarthritis patients with mild to moderate symptoms. The purpose of this study was to explore sagittal plane gait characteristics during the stance phase of gait in hip osteoarthritis patients not eligible for hip replacement surgery. First, compared to healthy controls, and second, when categorized into two subgroups of radiographic severity defined from a minimal joint space of ≤/>2 mm. Methods Sagittal plane kinematics and kinetics of the hip, knee and ankle joint were calculated for total joint excursion throughout the stance phase, as well as from the specific events initial contact, midstance, peak hip extension and toe-off following 3D gait analysis. In addition, the Western Ontario and McMaster Universities Osteoarthritis Index, passive hip range of motion, and isokinetic muscle strength of hip and knee flexion and extension were included as secondary outcomes. Data were checked for normality and differences evaluated with the independent Student’s t-test, Welch’s t-test and the independent Mann–Whitney U-test. A binary logistic regression model was used in order to control for velocity in key variables. Results Fourty-eight hip osteoarthritis patients and 22 controls were included in the final material. The patients walked significantly slower than the controls (p=0.002), revealed significantly reduced joint excursions of the hip (p<0.001) and knee (p=0.011), and a reduced hip flexion moment at midstance and peak hip extension (p<0.001). Differences were primarily manifested during the latter 50% of stance, and were persistent when controlling for velocity. Subgroup analyses of patients with minimal joint space ≤/>2 mm suggested that the observed deviations were more pronounced in patients with greater radiographic

  14. Rule-based algorithm for the classification of sitting postures in the sagittal plane from the Cardiff Body Match measurement system.

    PubMed

    Kulon, Janusz; Partlow, Adam; Gibson, Colin; Wilson, Ian; Wilcox, Steven

    2014-01-01

    The purpose of this paper is to present the design and implementation of a novel rule-based algorithm for the classification of sitting postures in the sagittal plane. The research focused on individuals with severe musculoskeletal problems and, thus, specific requirements for posture and pressure management. Clients' body shapes were captured using the Cardiff Body Match system developed by the Rehabilitation Engineering Unit, Cardiff and Vale University Health Board. The algorithm consists of four main steps: the first step is the symmetry line detection, the second step involves the mathematical analysis of the curvature of the backrest profile, the third step is the sitting posture classification and the fourth step is the extraction of the geometric parameters from the curve. The results show the classification system was successful in identifying four types of curves characterizing sitting postures using local derivatives as curve descriptors with an overall accuracy of 93.9%.

  15. Age-related differences in sagittal-plane knee function at heel-strike of walking are increased in osteoarthritic patients.

    PubMed

    Favre, J; Erhart-Hledik, J C; Andriacchi, T P

    2014-03-01

    To compare age-related patterns of gait with patterns associated with knee osteoarthritis (OA), the following hypotheses were tested: (H1) The sagittal-plane knee function during walking is different between younger and older asymptomatic subjects; (H2) The age-related differences in H1 are increased in patients with knee OA. Walking trials were collected for 110 participants (1.70 ± 0.09 m, 80 ± 14 kg). There were 29 younger asymptomatic subjects (29 ± 4 years) and 81 older participants (59 ± 9 years), that included 27 asymptomatic subjects and 28 and 26 patients with moderate and severe medial knee OA. Discrete variables characterizing sagittal-plane knee function were compared among the four groups using ANOVAs. During the heel-strike portion of the gait cycle at preferred walking speed, the knee was less extended and the shank less inclined in the three older groups compared to the younger asymptomatic group. There were similar differences between the severe OA group and the older asymptomatic and moderate OA groups. Both OA groups also had the femur less posterior relative to the tibia and smaller extension moment than the younger group. During terminal stance, the severe OA group had the knee less extended and smaller knee extension moment than the younger asymptomatic and older moderate OA groups. The differences in knee function, particularly those during heel-strike which were associated with both age and disease severity, could form a basis for looking at mechanical risk factors for initiation and progression of knee OA on a prospective basis. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  16. Correction of coronal plane deformities around the knee using a tension band plate in children younger than 10 years

    PubMed Central

    Kulkarni, Ruta M; Ilyas Rushnaiwala, Faizaan M; Kulkarni, GS; Negandhi, Rajiv; Kulkarni, Milind G; Kulkarni, Sunil G

    2015-01-01

    Background: Guided growth through temporary hemiepiphysiodesis has gained acceptance as the preferred primary treatment in treating pediatric lower limb deformities as it is minimally invasive with a lesser morbidity than the traditional osteotomy. The tension band plate is the most recent development in implants used for temporary hemiepiphysiodesis. Our aim was to determine its safety and efficacy in correcting coronal plane deformities around the knee in children younger than 10 years. Materials and Methods: A total of 24 children under the age of 10 were operated for coronal plane deformities around the knee with a single extra periosteal tension band plate and two nonlocking screws. All the children had a pathological deformity for which a detailed preoperative work-up was carried out to ascertain the cause of the deformity and rule out physiological ones. The average age at hemiepiphysiodesis was 5 years 3 months (range: 2 years to 9 years 1 month). Results: The plates were inserted for an average of 15.625 months (range: 7 months to 29 months). All the patients showed improvement in the mechanical axis. Two patients showed partial correction. Two cases of screw loosening were observed. In the genu valgum group, the tibiofemoral angle improved from a preoperative mean of 19.89° valgus (range: 10° valgus to 40° valgus) to 5.72° valgus (range: 2° varus to 10° valgus). In patients with genu varum the tibiofemoral angle improved from a mean of 28.27° varus (range: 13° varus to 41° varus) to 1.59° valgus (range: 0-8° valgus). Conclusion: Temporary hemiepiphysiodesis through the application of the tension band plate is an effective method to correct coronal plane deformities around the knee with minimal complications. Its ease and accuracy of insertion has extended the indication of temporary hemiepiphysiodesis to patients younger than 10 years and across a wide variety of diagnosis including pathological physis, which were traditionally out of the

  17. Coronal rhytidectomy in conjunction with deep plane walking sutures, modified Hotz-Celsus and lateral canthoplasty procedure in a dog with excessive brow droop.

    PubMed

    McCallum, Patrick; Welser, Jennifer

    2004-01-01

    This case report describes a unique technique of rhytidectomy in a Bloodhound to repair excessive brow folding and droop complicating underlying entropion. This case posed specific challenges due to the loose fascial plane connective tissue. A large circular area of coronal skin was excised, followed by placement of deep plane walking fixation sutures for cosmetic realignment and to alleviate brow droop. In addition, a modified Hotz-Celsus procedure and lateral canthoplasty were performed to address the primary entropion. The coronal rhytidectomy was considered a successful approach to repair excessive brow droop in this Bloodhound.

  18. Reliability of sagittal plane hip, knee, and ankle joint angles from a single frame of video data using the GAITRite camera system.

    PubMed

    Ross, Sandy A; Rice, Clinton; Von Behren, Kristyn; Meyer, April; Alexander, Rachel; Murfin, Scott

    2015-01-01

    The purpose of this study was to establish intra-rater, intra-session, and inter-rater, reliability of sagittal plane hip, knee, and ankle angles with and without reflective markers using the GAITRite walkway and single video camera between student physical therapists and an experienced physical therapist. This study included thirty-two healthy participants age 20-59, stratified by age and gender. Participants performed three successful walks with and without markers applied to anatomical landmarks. GAITRite software was used to digitize sagittal hip, knee, and ankle angles at two phases of gait: (1) initial contact; and (2) mid-stance. Intra-rater reliability was more consistent for the experienced physical therapist, regardless of joint or phase of gait. Intra-session reliability was variable, the experienced physical therapist showed moderate to high reliability (intra-class correlation coefficient (ICC) = 0.50-0.89) and the student physical therapist showed very poor to high reliability (ICC = 0.07-0.85). Inter-rater reliability was highest during mid-stance at the knee with markers (ICC = 0.86) and lowest during mid-stance at the hip without markers (ICC = 0.25). Reliability of a single camera system, especially at the knee joint shows promise. Depending on the specific type of reliability, error can be attributed to the testers (e.g. lack of digitization practice and marker placement), participants (e.g. loose fitting clothing) and camera systems (e.g. frame rate and resolution). However, until the camera technology can be upgraded to a higher frame rate and resolution, and the software can be linked to the GAITRite walkway, the clinical utility for pre/post measures is limited.

  19. Asymmetry of the leg alignment affects trunk bending in the coronal plane after unilateral total knee arthroplasty.

    PubMed

    Harato, Kengo; Yoshida, Hiroki; Otani, Toshiro

    2013-08-01

    Unilateral total knee arthroplasty (TKA) would produce asymmetric changes of lower extremity in patients with bilateral varus deformity. Our purpose was to investigate whether asymmetry of the leg alignment would affect trunk bending in the coronal plane after unilateral TKA. Twenty patients (mean 76 years old) with bilateral end-stage knee osteoarthritis (OA) participated. Spine images during relaxed standing were obtained on pre- and postoperative day 21. As a result, the shoulder tilted more to the TKA side and the pelvis inclined more to the contralateral OA side. These results suggested that the trunk would bend away from the contralateral OA side after unilateral TKA in patients with bilateral end-stage knee OA and varus deformity. Asymmetry of the leg alignment led to asymmetric trunk bending.

  20. How much does the human medial gastrocnemius muscle contribute to ankle torques outside the sagittal plane?☆

    PubMed Central

    Vieira, Taian M.M.; Minetto, Marco A.; Hodson-Tole, Emma F.; Botter, Alberto

    2013-01-01

    Ankle movements in the frontal plane are less prominent though not less relevant than movements in the plantar or dorsal flexion direction. Walking on uneven terrains and standing on narrow stances are examples of circumstances likely imposing marked demands on the ankle medio-lateral stabilization. Following our previous evidence associating lateral bodily sways in quiet standing to activation of the medial gastrocnemius (MG) muscle, in this study we ask: how large is the MG contribution to ankle torque in the frontal plane? By arranging stimulation electrodes in a selective configuration, current pulses were applied primarily to the MG nerve branch of ten subjects. The contribution of populations of MG motor units of progressively smaller recruitment threshold to ankle torque was evaluated by increasing the stimulation amplitude by fixed amounts. From smallest intensities (12–32 mA) leading to the firstly observable MG twitches in force-plate recordings, current pulses reached intensities (56–90 mA) below which twitches in other muscles could not be observed from the skin. Key results showed a substantial MG torque contribution tending to rotate upward the foot medial aspect (ankle inversion). Nerve stimulation further revealed a linear relationship between the peak torque of ankle plantar flexion and inversion, across participants (Pearson R > .81, p < .01). Specifically, regardless of the current intensity applied, the peak torque of ankle inversion amounted to about 13% of plantar flexion peak torque. Physiologically, these results provide experimental evidence that MG activation may contribute to stabilize the body in the frontal plane, especially under situations of challenged stability. PMID:23992638

  1. Change in Talar Translation in the Coronal Plane After Mobile-Bearing Total Ankle Replacement and Its Association with Lower-Limb and Hindfoot Alignment.

    PubMed

    Yi, Young; Cho, Jae-Ho; Kim, Ji-Beom; Kim, Jae-Young; Park, Su-Yeon; Lee, Woo Chun

    2017-02-15

    Mobile-bearing total ankle replacement (TAR) enables motion at the tibial implant-polyethylene insert interface. This motion could lead to coronal translation of the talus relative to the tibia and may affect radiographic outcome. We aimed to assess the translation of the talus before and after mobile-bearing TAR to determine whether translation of the talus after TAR is associated with coronal plane alignment of the lower limb and hindfoot as well as to investigate the complications associated with talar translation. In this retrospective cohort study, we enrolled 153 patients (159 ankles) with a minimum follow-up of 3 years who underwent mobile-bearing TAR. The location of the talus in the coronal plane was quantified with use of talar center migration (TCM) on anteroposterior radiographs both preoperatively and at postoperative intervals, and the relationship between them was investigated. Radiographic parameters in the coronal plane-including mechanical axis deviation (MAD), lateral distal tibial angle (LDTA), hindfoot alignment angle, and hindfoot moment arm-were measured. The relationship between TCM and radiographic parameters in the coronal plane was assessed in each group. The complications associated with talar translation were examined during the same period. During the 36-month follow-up period, the postoperative TCM showed a strong relationship with the preoperative TCM. Moreover, MAD, LDTA, and hindfoot alignment were significantly related to talar translation (p < 0.01). Complications included medial malleolar impingement in 5 cases (including delayed medial malleolar fracture due to medial impingement in 2 cases), insert dislocation in 1 case, and edge-loading in 2 cases; all of the cases with complications demonstrated implant overhang with talar translation. Talar translation in the coronal plane after mobile-bearing TAR correlates with the preoperative talar translation. Talar translation arises from deformities of MAD, LDTA, and hindfoot

  2. Validity and Reproducibility of the Measurements Obtained Using the Flexicurve Instrument to Evaluate the Angles of Thoracic and Lumbar Curvatures of the Spine in the Sagittal Plane

    PubMed Central

    de Oliveira, Tatiana Scheeren; Candotti, Cláudia Tarragô; La Torre, Marcelo; Pelinson, Patricia Paula Tonin; Furlanetto, Tássia Silveira; Kutchak, Fernanda Machado; Loss, Jefferson Fagundes

    2012-01-01

    Objective. to verify the validity and reproducibility of using the flexicurve to measure the angles of the thoracic and lumbar curvatures. Method. 47 subjects were evaluated by: (1) palpation and marking of the spinous processes using lead markers, (2) using X-rays in the sagittal plane to measure the Cobb angles, (3) molding the flexicurve to the spine, and (4) drawing the contour of the flexicurve onto graph paper. The angle of curvature was determined with the flexicurve based on a 3rd order polynomial. Results. No differences were found between the Cobb angles and the angles obtained using the flexicurve in thoracic and lumbar curvatures (P > 0.05). Correlations were strong and significant for the thoracic (r = 0.72, P < 0.01) and lumbar (r = 0.60, P < 0.01) curvatures. Excellent and significant correlations were found for both the intraevaluator and interevaluator measurements. Conclusion. The results show that there is no significant difference between the values obtained using the flexicurve and those obtained using the X-ray procedure and that there is a strong correlation between the two methods. This, together with the excellent level of inter- and intraevaluator reproducibility justifies its recommendation for use in clinical practice. PMID:22619723

  3. A comparison of four techniques to measure anterior and posterior vertebral body heights and sagittal plane wedge angles in adolescent idiopathic scoliosis.

    PubMed

    Newell, Nicolas; Grant, Caroline A; Keenan, Bethany E; Izatt, Maree T; Pearcy, Mark J; Adam, Clayton J

    2017-04-01

    Adolescent idiopathic scoliosis (AIS) is a three-dimensional (3D) spinal deformity of unknown aetiology. Increased growth of the anterior part of the vertebrae known as anterior overgrowth has been proposed as a potential driver for AIS initiation and progression. To date, there has been no objective evaluation of the 3D measurement techniques used to identify this phenomenon and the majority of previous studies use 2D planar assessments which contain inherent projection errors due to the vertebral rotation which is part of the AIS deformity. In this study, vertebral body (VB) heights and wedge angles were measured in a test group of AIS patients and healthy controls using four different image analysis and measurement techniques. Significant differences were seen between the techniques in terms of VB heights and VB wedge angles. The low variability, and the fact that the rotation and tilt of the deformed VBs are taken into account, suggests that the proposed technique using the full 3D orientation of the vertebrae is the most reliable method to measure anterior and posterior VB heights and sagittal plane wedge angles in 3D image data sets. These results have relevance for future investigations that aim to quantify anterior overgrowth in AIS patients for comparison with healthy controls.

  4. Posterior Tibial Slope Angle Correlates With Peak Sagittal and Frontal Plane Knee Joint Loading During Robotic Simulations of Athletic Tasks.

    PubMed

    Bates, Nathaniel A; Nesbitt, Rebecca J; Shearn, Jason T; Myer, Gregory D; Hewett, Timothy E

    2016-07-01

    Tibial slope angle is a nonmodifiable risk factor for anterior cruciate ligament (ACL) injury. However, the mechanical role of varying tibial slopes during athletic tasks has yet to be clinically quantified. To examine the influence of posterior tibial slope on knee joint loading during controlled, in vitro simulation of the knee joint articulations during athletic tasks. Descriptive laboratory study. A 6 degree of freedom robotic manipulator positionally maneuvered cadaveric knee joints from 12 unique specimens with varying tibial slopes (range, -7.7° to 7.7°) through drop vertical jump and sidestep cutting tasks that were derived from 3-dimensional in vivo motion recordings. Internal knee joint torques and forces were recorded throughout simulation and were linearly correlated with tibial slope. The mean (±SD) posterior tibial slope angle was 2.2° ± 4.3° in the lateral compartment and 2.3° ± 3.3° in the medial compartment. For simulated drop vertical jumps, lateral compartment tibial slope angle expressed moderate, direct correlations with peak internally generated knee adduction (r = 0.60-0.65), flexion (r = 0.64-0.66), lateral (r = 0.57-0.69), and external rotation torques (r = 0.47-0.72) as well as inverse correlations with peak abduction (r = -0.42 to -0.61) and internal rotation torques (r = -0.39 to -0.79). Only frontal plane torques were correlated during sidestep cutting simulations. For simulated drop vertical jumps, medial compartment tibial slope angle expressed moderate, direct correlations with peak internally generated knee flexion torque (r = 0.64-0.69) and lateral knee force (r = 0.55-0.74) as well as inverse correlations with peak external torque (r = -0.34 to -0.67) and medial knee force (r = -0.58 to -0.59). These moderate correlations were also present during simulated sidestep cutting. The investigation supported the theory that increased posterior tibial slope would lead to greater magnitude knee joint moments, specifically

  5. Posterior Tibial Slope Angle Correlates With Peak Sagittal and Frontal Plane Knee Joint Loading During Robotic Simulations of Athletic Tasks

    PubMed Central

    Bates, Nathaniel A.; Nesbitt, Rebecca J.; Shearn, Jason T.; Myer, Gregory D.; Hewett, Timothy E.

    2017-01-01

    Background Tibial slope angle is a nonmodifiable risk factor for anterior cruciate ligament (ACL) injury. However, the mechanical role of varying tibial slopes during athletic tasks has yet to be clinically quantified. Purpose To examine the influence of posterior tibial slope on knee joint loading during controlled, in vitro simulation of the knee joint articulations during athletic tasks. Study Design Descriptive laboratory study. Methods A 6 degree of freedom robotic manipulator positionally maneuvered cadaveric knee joints from 12 unique specimens with varying tibial slopes (range, −7.7° to 7.7°) through drop vertical jump and sidestep cutting tasks that were derived from 3-dimensional in vivo motion recordings. Internal knee joint torques and forces were recorded throughout simulation and were linearly correlated with tibial slope. Results The mean (6SD) posterior tibial slope angle was 2.2° ± 4.3° in the lateral compartment and 2.3° ± 3.3° in the medial compartment. For simulated drop vertical jumps, lateral compartment tibial slope angle expressed moderate, direct correlations with peak internally generated knee adduction (r = 0.60–0.65), flexion (r = 0.64–0.66), lateral (r = 0.57–0.69), and external rotation torques (r = 0.47–0.72) as well as inverse correlations with peak abduction (r = −0.42 to −0.61) and internal rotation torques (r = −0.39 to −0.79). Only frontal plane torques were correlated during sidestep cutting simulations. For simulated drop vertical jumps, medial compartment tibial slope angle expressed moderate, direct correlations with peak internally generated knee flexion torque (r = 0.64–0.69) and lateral knee force (r = 0.55–0.74) as well as inverse correlations with peak external torque (r = −0.34 to 20.67) and medial knee force (r = −0.58 to −0.59). These moderate correlations were also present during simulated sidestep cutting. Conclusion The investigation supported the theory that increased posterior

  6. The use of the T1 sagittal angle in predicting overall sagittal balance of the spine.

    PubMed

    Knott, Patrick T; Mardjetko, Steven M; Techy, Fernando

    2010-11-01

    A balanced sagittal alignment of the spine has been shown to strongly correlate with less pain, less disability, and greater health status scores. To restore proper sagittal balance, one must assess the position of the occiput relative to the sacrum. The assessment of spinal balance preoperatively can be challenging, whereas predicting postoperative balance is even more difficult. This study was designed to evaluate and quantify multiple factors that influence sagittal balance. Retrospective analysis of existing spinal radiographs. A retrospective review of 52 adult spine patient records was performed. All patients had full-column digital radiographs that showed all the important skeletal landmarks necessary for accurate measurement. The average age of the patient was 53 years. Both genders were equally represented. The radiographs were measured using standard techniques to obtain the following parameters: scoliosis in the coronal plane; lordosis or kyphosis of the cervical, thoracic, and lumbar spine; the T1 sagittal angle (angle between a horizontal line and the superior end plate of T1); the angle of the dens in the sagittal plane; the angle of the dens in relation to the occiput; the sacral slope; the pelvic incidence; the femoral-sacral angle; and finally, the sagittal vertical axis (SVA) measured from both the dens of C2 and from C7. It was found that the SVA when measured from the dens was on average 16 mm farther forward than the SVA measured from C7 (p<.0001). The dens plumb line (SVA(dens)) was then used in the study. An analysis was done to examine the relationship between SVA(dens) and each of the other measurements. The T1 sagittal angle was found to have a moderate positive correlation (r=0.65) with SVA(dens), p<.0001, indicating that the amount of sagittal T1 tilt can be used as a good predictor of overall sagittal balance. When examining the other variables, it was found that cervical lordosis had a weak correlation (r=0.37) with SVA(dens) that was

  7. Coronal plane segmental flexibility in thoracic adolescent idiopathic scoliosis assessed by fulcrum-bending radiographs.

    PubMed

    Hasler, Carol-Claudius; Hefti, Fritz; Büchler, Philippe

    2010-05-01

    Knowledge about segmental flexibility in adolescent idiopathic scoliosis is crucial for a better biomechanical understanding, particularly for the development of fusionless, growth-guiding techniques. Currently, there is lack of data in this field. The objective of this study was, therefore, to compute segmental flexibility indices (standing angle minus corrected angle/standing angle). We compared segmental disc angles in 76 preoperative sets of standing and fulcrum-bending radiographs of thoracic curves (paired, two-tailed t tests, p < 0.05). The mean standing Cobb angle was 59.7 degrees (range 41.3 degrees -95 degrees ) and the flexibility index of the curve was 48.6% (range 16.6-78.8%). The disc angles showed symmetric periapical distribution with significant decrease (all p values <0.0001) for every cephalad (+) and caudad (-) level change. The periapical levels +1 and -1 wedged at 8.3 degrees and 8.7 degrees (range 3.5 degrees -14.8 degrees ), respectively. All angles were significantly smaller on the-bending views (p values <0.0001). We noted mean periapical flexibility indices of 46% (+1), 49% (-1), 57% (+2) and 81% (-2), which were significantly less (p < 0.001) than for the group of remote levels 105% (+3), 149% (-3), 231% (+4) and 300% (-4). The discal and bony wedging was 60 and 40%, respectively, and mean values 35 degrees and 24 degrees (p < 0.0001). Their relationship with the Cobb angle showed a moderate correlation (r = 0.56 and 0.45). Functional, radiographic analysis of idiopathic thoracic scoliosis revealed significant, homogenous segmental tethering confined to four periapical levels. Future research will aim at in vivo segmental measurements in three planes under defined load to provide in-depth data for novel therapeutic strategies.

  8. Coronal plane segmental flexibility in thoracic adolescent idiopathic scoliosis assessed by fulcrum-bending radiographs

    PubMed Central

    Hefti, Fritz; Büchler, Philippe

    2010-01-01

    Knowledge about segmental flexibility in adolescent idiopathic scoliosis is crucial for a better biomechanical understanding, particularly for the development of fusionless, growth-guiding techniques. Currently, there is lack of data in this field. The objective of this study was, therefore, to compute segmental flexibility indices (standing angle minus corrected angle/standing angle). We compared segmental disc angles in 76 preoperative sets of standing and fulcrum-bending radiographs of thoracic curves (paired, two-tailed t tests, p < 0.05). The mean standing Cobb angle was 59.7° (range 41.3°–95°) and the flexibility index of the curve was 48.6% (range 16.6–78.8%). The disc angles showed symmetric periapical distribution with significant decrease (all p values <0.0001) for every cephalad (+) and caudad (−) level change. The periapical levels +1 and −1 wedged at 8.3° and 8.7° (range 3.5°–14.8°), respectively. All angles were significantly smaller on the-bending views (p values <0.0001). We noted mean periapical flexibility indices of 46% (+1), 49% (−1), 57% (+2) and 81% (−2), which were significantly less (p < 0.001) than for the group of remote levels 105% (+3), 149% (−3), 231% (+4) and 300% (−4). The discal and bony wedging was 60 and 40%, respectively, and mean values 35° and 24° (p < 0.0001). Their relationship with the Cobb angle showed a moderate correlation (r = 0.56 and 0.45). Functional, radiographic analysis of idiopathic thoracic scoliosis revealed significant, homogenous segmental tethering confined to four periapical levels. Future research will aim at in vivo segmental measurements in three planes under defined load to provide in-depth data for novel therapeutic strategies. PMID:20186443

  9. Effects of mid-foot contact area ratio on lower body kinetics/kinematics in sagittal plane during stair descent in women.

    PubMed

    Lee, Jinkyu; Hong, Yoon No Gregory; Shin, Choongsoo S

    2016-07-01

    The mid-foot contact area relative to the total foot contact area can facilitate foot arch structure evaluation. A stair descent motion consistently provides initial fore-foot contact and utilizes the foot arch more actively for energy absorption. The purpose of this study was to compare ankle and knee joint angle, moment, and work in sagittal plane during stair descending between low and high Mid-Foot-Contact-Area (MFCA) ratio group. The twenty-two female subjects were tested and classified into two groups (high MFCA and low MFCA) using their static MFCA ratios. The ground reaction force (GRF) and kinematics of ankle and knee joints were measured while stair descending. During the period between initial contact and the first peak in vertical GRF (early absorption phase), ankle negative work for the low MFCA ratio group was 33% higher than that for the high MFCA ratio group (p<0.05). However, ankle negative work was not significantly different between the two groups during the period between initial contact and peak dorsiflexion angle (early absorption phase+late absorption phase). The peak ankle dorsiflexion angle was smaller in the low MFCA ratio group (p<0.05). Our results suggest that strategy of energy absorption at the ankle and foot differs depending upon foot arch types classified by MFCA. The low MFCA ratio group seemed to absorb more impact energy using strain in the planar fascia during early absorption phase, whereas the high MFCA ratio group absorbed more impact energy using increased dorsiflexion during late absorption phase.

  10. Center of mass trajectory and orientation to ankle and knee in sagittal plane is maintained with forward lean when backpack load changes during treadmill walking.

    PubMed

    Caron, Robert R; Wagenaar, Robert C; Lewis, Cara L; Saltzman, Elliot; Holt, Kenneth G

    2013-01-04

    Maintaining the normal shape and amplitude of the vertical trajectory of the center of mass (COM) during stance has been shown to maximize the efficiency of unloaded gait. Kinematic adaptations to load carriage, such as forward lean have yet to be understood in relation to COM movement. The purpose of this study is to better understand how load impacts the vertical COM(TSYS) trajectory and to clarify the impact of forward lean as it relates to the dynamics of sagittal plane COM(TSYS) movement during stance with changing load. 17 subjects walked on treadmill at a constant preferred walking velocity while nine different loads ranging from 12.5% to 40% bodyweight were systematically added and removed from a backpack. Kinematic data were collected using an Optotrak, three-dimensional motion analysis system and used to estimate position of the COM as well as segment and COM-to-joint vector orientation angles. The shape and amplitude of the COM vertical trajectory was maintained across all loaded conditions. The orientations of COM-to-ankle and -knee vectors were maintained in all loaded conditions except the heaviest load (40% BW). Results suggest that forward lean changed linearly with changes in load to maintain the COM-to-ankle and -knee vector orientations. COM vertical trajectory was maintained by a combination of invariants including lower-limb segment angles and a constant direction of toe-off impulse vector. The kinematic invariants found suggest a simplified control mechanism by which the system limits degrees of freedom and potentially minimizes torque about lower-extremity joints with added load.

  11. A gender-related difference in the contribution of the knee musculature to sagittal-plane shear stiffness in subjects with similar knee laxity.

    PubMed

    Wojtys, Edward M; Ashton-Miller, James A; Huston, Laura J

    2002-01-01

    Women's susceptibility to injuries involving the anterior cruciate ligament remains unexplained. Volitional contraction of the knee musculature is known to increase the resistance of the knee to shear deformation, raising the possibility that muscles play a part in protecting the anterior cruciate ligament during hazardous activities. We therefore tested the hypothesis that a volitional co-contraction of the knee muscles increases the sagittal-plane shear stiffness (or resistance to anterior tibial translation) of the knee more in men than in women. Twenty-three volunteers (ten men and thirteen women; mean age, 24.7 +/- 5.4 years), all with anterior tibial translation of 6 mm, agreed to participate in the study. Each subject underwent a subjective evaluation of knee function and activity level, an arthrometric measurement of passive anterior tibial translation, and an isokinetic dynamometer strength test at 60 degrees/sec. A dynamic stress test was then performed to measure anterior tibial translation while simultaneously monitoring lower-extremity muscle response. Maximum co-contraction of the knee musculature significantly decreased mean anterior tibial translation in both men and women (from 7.8 mm to 2.2 mm in men and from 6.5 mm to 3.1 mm in women). The corresponding percentage increase in shear stiffness of the knee was significantly greater (p = 0.003) in men (379%) than in women (212%). The results suggested that women have a diminished potential for muscular protection of passive structures of the knee in anterior tibial translation. Maximal muscular protection of the anterior cruciate ligament in women may be less than that in men. This may be one factor explaining why more women than men are apt to sustain injuries to the anterior cruciate ligament.

  12. Accuracy and repeatability of quantitative fluoroscopy for the measurement of sagittal plane translation and finite centre of rotation in the lumbar spine.

    PubMed

    Breen, Alexander; Breen, Alan

    2016-07-01

    Quantitative fluoroscopy (QF) was developed to measure intervertebral mechanics in vivo and has been found to have high repeatability and accuracy for the measurement of intervertebral rotations. However, sagittal plane translation and finite centre of rotation (FCR) are potential measures of stability but have not yet been fully validated for current QF. This study investigated the repeatability and accuracy of QF for measuring these variables. Repeatability was assessed from L2-S1 in 20 human volunteers. Accuracy was investigated using 10 consecutive measurements from each of two pairs of linked and instrumented dry human vertebrae as reference; one which tilted without translation and one which translated without tilt. The results found intra- and inter-observer repeatability for translation to be 1.1mm or less (SEM) with fair to substantial reliability (ICC 0.533-0.998). Intra-observer repeatability of FCR location for inter-vertebral rotations of 5° and above ranged from 1.5mm to 1.8mm (SEM) with moderate to substantial reliability (ICC 0.626-0.988). Inter-observer repeatability for FCR ranged from 1.2mm to 5.7mm, also with moderate to substantial reliability (ICC 0.621-0.878). Reliability was substantial (ICC>0.81) for 10/16 measures for translation and 5/8 for FCR location. Accuracy for translation was 0.1mm (fixed centre) and 2.2mm (moveable centre), with an FCR error of 0.3mm(x) and 0.4mm(y) (fixed centre). This technology was found to have a high level of accuracy and with a few exceptions, moderate to substantial repeatability for the measurement of translation and FCR from fluoroscopic motion sequences.

  13. The independent effect of added mass on the stability of the sagittal plane leg kinematics during steady-state human walking.

    PubMed

    Arellano, Christopher J; O'Connor, Daniel P; Layne, Charles; Kurz, Max J

    2009-06-01

    This study investigated the independent effect of added mass on the stability of the leg kinematics during human walking. We reasoned that adding mass would influence the body's inertial state and thus challenge the ability of the leg to redirect and accelerate the total mass of the body while walking. We hypothesized that walking with added mass would reduce the stability of the leg kinematics. Lower extremity sagittal plane joint kinematics were recorded for 23 subjects as they walked on a treadmill at their preferred speed with and without added mass. The total mass of each subject was manipulated with combinations of simulated reduced gravity and added load. The stability of the leg kinematics was evaluated by computing the eigenvalues of the Poincaré map (i.e. Floquet analysis) that defined the position and velocity of the right hip, knee and ankle at heel-contact and mid-swing. Significant differences in stability were found between the various added mass conditions (P=0.040) and instant in the gait cycle (P=0.001). Post-hoc analysis revealed that walking with 30% added mass compromised the stability of the leg kinematics compared with walking without additional mass (P=0.031). In addition, greater instability was detected at the instance of heel-contact compared with mid-swing (P=0.001). Our results reveal that walking with added mass gives rise to greater disturbances in the leg kinematics, and may be related to the redirection and acceleration of the body throughout the gait cycle. Walking with added mass reduces the stability of the leg kinematics and possibly the overall balance of the walking pattern.

  14. Radiographic Parameters in Adult Degenerative Scoliosis and Different Parameters Between Sagittal Balanced and Imbalanced ADS Patients.

    PubMed

    Yang, Changwei; Yang, Mingyuan; Chen, Yuanyuan; Wei, Xianzhao; Ni, Haijian; Chen, Ziqiang; Li, Jingfeng; Bai, Yushu; Zhu, Xiaodong; Li, Ming

    2015-07-01

    A retrospective study. To summarize and describe the radiographic parameters of adult degenerative scoliosis (ADS) and explore the radiological parameters which are significantly different in sagittal balanced and imbalanced ADS patients. ADS is the most common type of adult spinal deformity. However, no comprehensive description of radiographic parameters in ADS patients has been made, and few studies have been performed to explore which radiological parameters are significantly different between sagittal balanced and imbalanced ADS patients. Medical records of ADS patients in our outpatient clinic from January 2012 to January 2014 were reviewed. Demographic data including age and sex, and radiographic data including the coronal Cobb angle, location of apical vertebra/disc, convexity of the curve, degree of apical vertebra rotation, curve segments, thoracic kyphosis (TK), lumbar lordosis (LL), thoracolumbar kyphosis (TL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), sagittal vertical axis (SVA), and PI minus LL (PI-LL) were reviewed to make comprehensive description of radiographic parameters of ADS. Furthermore, patients were divided into 2 groups according to whether the patients' sagittal plane was balanced: Group A (imbalanced, SVA > 5 cm) and Group B (balanced, SVA  ≤ 5 cm). Demographic and radiological parameters were compared between these 2 groups. A total of 99 patients were included in this study (Group A = 33 and Group B = 66; female = 83 and male = 16; sex ratio = 5:1). The median of age were 67 years (range: 41-92 years). The median of coronal Cobb angle and length of curve was 23 (range: 10-75°) and 5 segments (range: 3-7), respectively. The most common location of apical vertebra was at L2 to L3 (81%) and the median of degree of apical vertebra rotation was 2° (range: 1-3). Our study also showed significant correlations between coronal Cobb angle and curve segments (r = 0.23, P < 0.005) and degree of apical vertebra rotation (r

  15. Can we use intraoperative femoral tunnel length measurement as a clue for proper femoral tunnel placement on coronal plane during ACL reconstruction?

    PubMed

    Celiktas, Mustafa; Kose, Ozkan; Sarpel, Yaman; Gulsen, Mahir

    2015-04-01

    Successful anterior cruciate ligament (ACL) reconstruction is dependent on correct placement of both tibial and femoral tunnels. The purpose of this study is to investigate whether we can use intraoperative femoral tunnel length measurement to estimate the correct femoral tunnel placement on coronal plane. This prospective study comprised 164 consecutive patients who underwent ACL reconstruction surgery. Transtibial or anteromedial portal technique is used for drilling the femoral tunnels. The length of the femoral tunnel was measured during the operation. The femoral tunnel coronal plane angle was calculated on the postoperative tunnel radiographs. A statistical comparison was made of the lengths of the tunnel, the techniques used drilling and the femoral tunnel angles. The far anteromedial portal was used in 81 (49%) cases and the transtibial technique in 83 (51%) cases. The mean femoral tunnel length was 42 ± 6.4 mm and the mean femoral tunnel coronal angle was 41.1° ± 11.6. The tunnel angle in the transtibial technique was determined as significantly low compared to the far anteromedial portal technique (32.6°:49.8°) and the tunnel length was significantly longer (45.8:38.1 mm) (p < 0.001). In the statistical analysis, it was found that a patient with a tunnel length of 41 mm and above had a 92.1% likelihood of femoral tunnel angle below 45°. Femoral tunnel length can be used as a clue for intraoperative evaluation of the femoral tunnel position. If the femoral tunnel length is greater than 41 mm, the coronal plane orientation of the femoral tunnel will be improper and not at a desired position.

  16. A portable system with sample rate of 250 Hz for characterization of knee and hip angles in the sagittal plane during gait

    PubMed Central

    2014-01-01

    Background Gait analysis and research have been developed to obtain characteristics of movement patterns of people while walking. However, traditional measuring systems present different drawbacks that reduce their use and application. Among those drawbacks one can find: high price, low sampling frequency and limiting number of steps to be analyzed. Traditional measuring gait systems carry out their measurement at frequencies oscillating between 60 to 100 Hz. It can be argued about the need of higher sampling rates for gait measurements. However small displacements of the knee or hip for example, cannot be seen with low frequencies required a more detailed sampling and higher frequency sampling. Bearing this in mind, in this paper is presented a 250 Hz system based on accelerometers for gait measurement, and the particularities of knee and hip angles during gait are highlighted. Methods The system was designed with a PCI data acquisition card instrumented with an FPGA to achieve a rate sample of 250 Hz. The accelerometers were placed in thighs and legs to calculate the joint angles of hip and knee in the sagittal plane. The angles were estimated using the acceleration polygon method without integrating the acceleration and without filters. Results The gait of thirty healthy people of Mexican phenotype was analyzed over a flat floor free of obstacles. The results showed the gait phases and particularities associated with the walking style and people's laterality; the movement patterns were similar in the thirty persons. Based on the results, the particularities as the maximum amplitude in the angles and the shape in the movement patterns were related to the anthropometry and people phenotype. Conclusions The sampling frequency was essential to record 340 samples in single gait cycle and so registering the gait cycle with its particularities. In this work were recorded an average of 8 to 10 gait cycles, and the results showed variation regarding works carried out

  17. Definition of bulky disease in early stage Hodgkin lymphoma in computed tomography era: prognostic significance of measurements in the coronal and transverse planes.

    PubMed

    Kumar, Anita; Burger, Irene A; Zhang, Zhigang; Drill, Esther N; Migliacci, Jocelyn C; Ng, Andrea; LaCasce, Ann; Wall, Darci; Witzig, Thomas E; Ristow, Kay; Yahalom, Joachim; Moskowitz, Craig H; Zelenetz, Andrew D

    2016-10-01

    Disease bulk is an important prognostic factor in early stage Hodgkin lymphoma, but its definition is unclear in the computed tomography era. This retrospective analysis investigated the prognostic significance of bulky disease measured in transverse and coronal planes on computed tomography imaging. Early stage Hodgkin lymphoma patients (n=185) treated with chemotherapy with or without radiotherapy from 2000-2010 were included. The longest diameter of the largest lymph node mass was measured in transverse and coronal axes on pre-treatment imaging. The optimal cut off for disease bulk was maximal diameter greater than 7 cm measured in either the transverse or coronal plane. Thirty patients with maximal transverse diameter of 7 cm or under were found to have bulk in coronal axis. The 4-year overall survival was 96.5% (CI: 93.3%, 100%) and 4-year relapse-free survival was 86.8% (CI: 81.9%, 92.1%) for all patients. Relapse-free survival at four years for bulky patients was 80.5% (CI: 73%, 88.9%) compared to 94.4% (CI: 89.1%, 100%) for non-bulky; Cox HR 4.21 (CI: 1.43, 12.38) (P=0.004). In bulky patients, relapse-free survival was not impacted in patients treated with chemoradiotherapy; however, it was significantly lower in patients treated with chemotherapy alone. In an independent validation cohort of 38 patients treated with chemotherapy alone, patients with bulky disease had an inferior relapse-free survival [at 4 years, 71.1% (CI: 52.1%, 97%) vs 94.1% (CI: 83.6%, 100%), Cox HR 5.27 (CI: 0.62, 45.16); P=0.09]. Presence of bulky disease on multidimensional computed tomography imaging is a significant prognostic factor in early stage Hodgkin lymphoma. Coronal reformations may be included for routine Hodgkin lymphoma staging evaluation. In future, our definition of disease bulk may be useful in identifying patients who are most appropriate for chemotherapy alone.

  18. CORONAL CELLS

    SciTech Connect

    Sheeley, N. R. Jr.; Warren, H. P. E-mail: harry.warren@nrl.navy.mil

    2012-04-10

    We have recently noticed cellular features in Fe XII 193 A images of the 1.2 MK corona. They occur in regions bounded by a coronal hole and a filament channel, and are centered on flux elements of the photospheric magnetic network. Like their neighboring coronal holes, these regions have minority-polarity flux that is {approx}0.1-0.3 times their flux of majority polarity. Consequently, the minority-polarity flux is 'grabbed' by the majority-polarity flux to form low-lying loops, and the remainder of the network flux escapes to connect with its opposite-polarity counterpart in distant active regions of the Sun. As these regions are carried toward the limb by solar rotation, the cells disappear and are replaced by linear plumes projecting toward the limb. In simultaneous views from the Solar Terrestrial Relations Observatory and Solar Dynamics Observatory spacecraft, these plumes project in opposite directions, extending away from the coronal hole in one view and toward the hole in the other view, suggesting that they are sky-plane projections of the same radial structures. We conclude that these regions are composed of closely spaced radial plumes, extending upward like candles on a birthday cake and visible as cells when seen from above. We suppose that a coronal hole has this same discrete, cellular magnetic structure, but that it is not seen until the encroachment of opposite-polarity flux closes part or all of the hole.

  19. Application of Ni-Ti Alloy connector for the treatment of comminuted coronal plane supracondylar-condylar femoral fractures: a retrospective review of 21 patients

    PubMed Central

    2013-01-01

    Background Our preliminary retrospective study assessed outcomes after the use of Ni-Ti arched shape-memory connector (ASC) combined with partially threaded cancellous screws (PTCS) to repair coronal plane supracondylar-condylar femoral fractures. Methods Twenty-one patients (16 men and 5 women) with a mean age of 34.1 years (range, 28 to 44 years) with coronal plane supracondylar and condylar fractures of the distal femur were included in this study. Each patient underwent open reduction and internal fixation using the ASC and PTCS. Active functional exercises with restricted weight bearing were initiated the first postoperative day. A gradual increase in weight bearing status and range of motion was permitted and subjects progressed to full weight bearing by 8 weeks. Surgical time, blood loss, postoperative knee range of motion, American Knee Society Scores (KSS), and postoperative complications were assessed. Results The mean surgical time was 75 mins (range, 45 to 100 mins) and average blood loss was 105 ml (range, 35 to 130 ml). Mean follow-up was 65 months (range, 22 to 90 months). No subjects demonstrated evidence of osteonecrosis or arthritis at the final follow-up. The mean KSS was excellent (≥85) in 8 subjects, good (70-84) in 11 subjects, and fair (60-69) in 2 subjects. The mean active range of motion of knee flexion at final follow-up was 100 degrees (range, 85 to 110 degrees). Conclusions ASC combined with PTCS can serve as an effective means for managing comminuted femoral fractures that extend from the condyle to the supracondylar region. However, further prospective comparative studies and biomechanical analyses are needed to evaluate long-term outcomes using these materials. PMID:24341860

  20. Immediate coronal plane kinetic effects of novel lateral-offset sole shoes and lateral-wedge insole shoes in healthy individuals.

    PubMed

    Kang, Jong Woo; Park, Hae Soo; Na, Choon Kyun; Park, Jong Woong; Hong, Jungwha; Lee, Soon Hyuck

    2013-02-01

    To investigate kinetic differences in the coronal plane between healthy individuals wearing shoes with lateral-offset soles and shoes with lateral-wedge insoles while walking, hip abduction, knee adduction, and ankle abduction moments were estimated using a 3-dimensional motion analysis system under 3 different conditions: wearing conventional shoes (control), wearing lateral-offset sole shoes (condition A), and wearing lateral-wedge insole shoes (condition B). Forty-eight healthy individuals (24 men and 24 women) were tested. Condition A resulted in a significantly reduced peak knee adduction moment compared with the control (condition A=0.316 Nm/kg; control=0.380 Nm/kg; P=.006). The peak knee adduction moment of condition B was also lower than that of the control (condition B=0.299 Nm/kg; P=.002); however, the peak knee adduction moment was not significantly different between conditions A and B (P=.386). Condition B resulted in an increased mean ankle abduction moment in the stance phase compared with the control and condition A (control=0.007 Nm/kg; condition A=0.013 Nm/kg; condition B=0.023 Nm/kg) (control vs condition A, P=.051; control vs condition B, P<.001; condition A vs condition B, P=.002). The hip abduction moments were not significantly different between the control and condition A, control and condition B, or conditions A and B. Wearing lateral-offset sole shoes reduces the peak knee adduction moment and exerts less influence on ankle moment than does wearing lateral-wedge insole shoes. Neither lateral-offset sole shoes nor lateral-wedge insole shoes induce kinetic changes in the coronal plane of the hip.

  1. Comparison of perpendicular to the coronal plane versus medial inclination for atlas pedicle screw insertion: an anatomic and radiological study in human cadavers.

    PubMed

    Ma, Jun; Tang, Jian; Wang, Deguang; Zhu, Yucheng; Sui, Tao; Cao, Xiaojian

    2016-01-01

    To ascertain the anatomic and radiological parameters of the atlas (C1) pedicle and to explore a preferable method of C1 pedicle screw insertion. Thirty-four conserved human cadaveric cervical spines (20 males, 14 females) underwent computed tomography (CT) scanning. Trajectories P (perpendicular to the coronal plane) and I (with medial inclination) were designed for each C1 pedicle on CT images. External pedicle wall width, medullary cavity width, transverse angle, and optimal entry point along each trajectory were measured. Cortical screws of 3.5 mm in diameter were inserted into C1 pedicles along trajectory P and I, respectively, and wall perforation was assessed (post-operative CT scanning). The external pedicle wall width and medullary cavity width along trajectory I were significantly wider than trajectory P (P < 0.01). Although external pedicle wall widths were all greater than 3.5 mm, medullary cavity width <3.5 mm was found in 16.1 % pedicles along trajectory P and only 2.9 % along trajectory I. Transverse angle was 21.8° along trajectory I and 0° along trajectory P. Optimal entry point of trajectory I was 4.1 mm lateral from that of trajectory P. The lateral wall perforation rate was significantly lower along trajectory I than trajectory P (P < 0.05). C1 pedicle screw trajectory with medial inclination and more lateral entry points yielded wider medullary cavity width than that perpendicular to the coronal plane, and might minimize lateral wall perforation.

  2. Sagittal Spinopelvic Parameters of Young Children With Scoliosis.

    PubMed

    El-Hawary, Ron; Sturm, Peter F; Cahill, Patrick J; Samdani, Amer F; Vitale, Michael G; Gabos, Peter G; Bodin, Nathan D; d'Amato, Charles R; Harris, Colin; Howard, Jason J; Morris, Susan H; Smith, John T

    2013-09-01

    Retrospective, multicenter review of the spinopelvic parameters in young children with scoliosis. To describe sagittal alignment of the spine and pelvis in young children with scoliosis. The natural history of spinopelvic parameters has been defined for the first 10 years of life in normal children; however, they have not been described for children with scoliosis. Such information is important because these values can be used as a baseline for the assessment of radiographic outcomes after surgical intervention. Seven measures of sagittal alignment were taken from standing lateral radiographs of 80 children with scoliosis (coronal Cobb angle greater than 50°) and compared with age-matched normal children described in the literature. Statistical analysis was performed using 2-tailed Student t tests (level of significance = .05) and Pearson correlation coefficient. Patients had a mean age of 4.8 years (range, 1-10 years) and a mean Cobb angle of 72.0° ± 16°. Mean sagittal spine parameters were sagittal balance (2.2 ± 4 cm), thoracic kyphosis (38.0° ± 20.8°), and lumbar lordosis (49.0° ± 16.6°). These values were similar to those of children without scoliosis. Mean sagittal pelvic parameters were: pelvic incidence (46.5° ± 15.8°), pelvic tilt (10.7° ± 13.6°), sacral slope (35.5° ± 12.1°), and pelvic radius (55.7° ± 21.3°). Pelvic incidence was not significantly different from that of age-matched normal children; however, pelvic tilt was significantly higher and sacral slope was significantly lower in children with scoliosis. Sagittal plane spine parameters and some pelvic parameters were similar for young children with scoliosis versus age-matched normal children; however, children with scoliosis showed signs of increased pelvic tilt and decreased sacral slope. These values can be used as a baseline for both the natural history and the assessment of radiographic outcomes after surgical intervention. Copyright © 2013 Scoliosis Research Society

  3. Assessment of fetal midbrain and hindbrain in mid-sagittal cranial plane by three-dimensional multiplanar sonography. Part 2: application of nomograms to fetuses with posterior fossa malformations.

    PubMed

    Leibovitz, Z; Shkolnik, C; Haratz, K Krajden; Malinger, G; Shapiro, I; Lerman-Sagie, T

    2014-11-01

    To apply fetal midbrain (MB) and hindbrain (HB) nomograms, developed using three-dimensional multiplanar sonographic reconstruction (3D-MPR) in the mid-sagittal cranial plane, to fetuses with known posterior fossa malformations. In this retrospective study we examined sonographic volumes obtained by sagittal acquisition in 43 fetuses diagnosed with posterior fossa abnormalities and evaluated in the mid-sagittal cranial plane, using 3D-MPR, the following: MB parameters tectal length (TL) and anteroposterior midbrain diameter (APMD), and HB parameters anteroposterior pons diameter (APPD), superoinferior vermian diameter (SIVD) and anteroposterior vermian diameter (APVD). Fetuses were grouped, according to malformation, into eight categories: cobblestone malformation complex (CMC, n = 3), Chiari-II malformation (C-II, n = 7), pontocerebellar hypoplasia (PCH, n = 2), rhombencephalosynapsis (RES, n = 4), Dandy-Walker malformation (n = 8), vermian dysgenesis (VD, n = 7), persistent Blake's pouch cyst (n = 6) and megacisterna magna (n = 6). In each case and for each subgroup, the MB-HB biometric parameters and their z-scores were evaluated with reference to our new nomograms. The new MB-HB nomograms were able to identify the brainstem and vermian anomalies and differentiate fetuses with MB-HB malformations from those with isolated enlarged posterior fossa cerebrospinal fluid spaces. Use of the nomograms enabled detection of an elongated tectum in fetuses with CMC, C-II and RES, and a flattened pontine belly in cases of CMC, PCH and VD. In the fetuses with VD, the nomograms enabled division into three distinctive groups: (1) those with small SIVD and APVD, (2) those with normal SIVD but small APVD, and (3) those with small SIVD but normal APVD. Application of our new reference data, that for the first time include the MB, enables accurate diagnosis of brain malformations affecting the MB and HB and makes possible novel characterization of

  4. Sagittal deformities of the spine: factors influencing the outcomes and complications.

    PubMed

    Diebo, Bassel G; Henry, Jensen; Lafage, Virginie; Berjano, Pedro

    2015-01-01

    Degenerative changes have the potential to greatly disrupt the normal curvature of the spine, leading to sagittal malalignment. This phenomenon is often treated with operative modalities, such as osteotomies, though even with surgery, only one-third of patients may reach neutral alignment. Improvement in surgical outcomes may be achieved through better understanding of radiographic spino-pelvic parameters and their association with deformity. Methodical surgical planning, including selection of levels of instrumentation and site of the osteotomy, is crucial in determining the optimal plan for a patient's specific pathology and may minimize risk of developing postoperative proximal junctional kyphosis/failure. While sagittal alignment is essential in operative strategy, the coronal plane should not be overlooked, as it may affect the osteotomy technique. The concepts of sagittal balance and alignment are further complicated in patients with neuromuscular diseases such as Parkinson's disease, and appreciation of the interplay between anatomic and postural deformities is necessary to properly treat these patients. Finally, given the importance of sagittal alignment and the role of osteotomies in treatment for deformity, the need for future research becomes apparent. Novel intraoperative measurement techniques and three-dimensional analysis of the spine may allow for vastly improved operative correction. Furthermore, awareness of the relationship between alignment and balance, the soft tissue envelope, and compensatory mechanisms will provide a more comprehensive conception of the nature of spinal deformity and the modalities with which it is treated.

  5. Sagittal Plane Correction Using the Lateral Transpsoas Approach: A Biomechanical Study on the Effect of Cage Angle and Surgical Technique on Segmental Lordosis.

    PubMed

    Melikian, Rojeh; Yoon, Sangwook Tim; Kim, Jin Young; Park, Kun Young; Yoon, Caroline; Hutton, William

    2016-09-01

    Cadaveric biomechanical study. To determine the degree of segmental correction that can be achieved through lateral transpsoas approach by varying cage angle and adding anterior longitudinal ligament (ALL) release and posterior element resection. Lordotic cage insertion through the lateral transpsoas approach is being used increasingly for restoration of sagittal alignment. However, the degree of correction achieved by varying cage angle and ALL release and posterior element resection is not well defined. Thirteen lumbar motion segments between L1 and L5 were dissected into single motion segments. Segmental angles and disk heights were measured under both 50 N and 500 N compressive loads under the following conditions: intact specimen, discectomy (collapsed disk simulation), insertion of parallel cage, 10° cage, 30° cage with ALL release, 30° cage with ALL release and spinous process (SP) resection, 30° cage with ALL release, SP resection, facetectomy, and compression with pedicle screws. Segmental lordosis was not increased by either parallel or 10° cages as compared with intact disks, and contributed small amounts of lordosis when compared with the collapsed disk condition. Placement of 30° cages with ALL release increased segmental lordosis by 10.5°. Adding SP resection increased lordosis to 12.4°. Facetectomy and compression with pedicle screws further increased lordosis to approximately 26°. No interventions resulted in a decrease in either anterior or posterior disk height. Insertion of a parallel or 10° cage has little effect on lordosis. A 30° cage insertion with ALL release resulted in a modest increase in lordosis (10.5°). The addition of SP resection and facetectomy was needed to obtain a larger amount of correction (26°). None of the cages, including the 30° lordotic cage, caused a decrease in posterior disk height suggesting hyperlordotic cages do not cause foraminal stenosis. N/A.

  6. Sagittal endplate morphology of the lower lumbar spine.

    PubMed

    Lakshmanan, Palaniappan; Purushothaman, Balaji; Dvorak, Vlasta; Schratt, Walter; Thambiraj, Sathya; Boszczyk, Maximilian

    2012-05-01

    The sagittal profile of lumbar endplates is discrepant from current simplified disc replacement and fusion device design. Endplate concavity is symmetrical in the coronal plane but shows considerable variability in the sagittal plane, which may lead to implant-endplate mismatch. The aim of this investigation is to provide further analysis of the sagittal endplate morphology of the mid to lower lumbar spine study (L3–S1), thereby identifying the presence of common endplate shape patterns across these levels and providing morphological reference values complementing the findings of previous studies. Observational study. A total of 174 magnetic resonance imaging (MRI) scans of the adult lumbar spine from the digital archive of our centre, which met the inclusion criteria, were studied. Superior (SEP) and inferior (IEP) endplate shape was divided into flat (no concavity), oblong (homogeneous concavity) and ex-centric (inhomogeneous concavity). The concavity depth (ECD) and location of concavity apex (ECA) relative to endplate diameter of the vertebrae L3–S1 were determined. Flat endplates were only predominant at the sacrum SEP (84.5%). The L5 SEP was flat in 24.7% and all other endplates in less than 10%. The majority of endplates were concave with a clear trend of endplate shape becoming more ex-centric from L3 IEP (56.9% oblong vs. 37.4% ex-centric) to L5 IEP (4% oblong vs. 94.3% ex-centric). Ex-centric ECA were always found in the posterior half of the lumbar endplates. Both the oblong and ex-centric ECD was 2-3 mm on average with the IEP of a motion segment regularly possessing the greater depth. A sex- or age-related difference could not be found. The majority of lumbar endplates are concave, while the majority of sacral endplates are flat. An oblong and an ex-centric endplate shape can be distinguished, whereby the latter is more common at the lower lumbar levels. The apex of the concavity of ex-centric discs is located in the posterior half of the endplate

  7. Computer-assisted scheme for automated determination of imaging planes in cervical spinal cord MRI

    NASA Astrophysics Data System (ADS)

    Tsurumaki, Masaki; Tsai, Du-Yih; Lee, Yongbum; Sekiya, Masaru; Kazama, Kiyoko

    2009-02-01

    This paper presents a computerized scheme to assist MRI operators in accurate and rapid determination of sagittal sections for MRI exam of cervical spinal cord. The algorithm of the proposed scheme consisted of 6 steps: (1) extraction of a cervical vertebra containing spinal cord from an axial localizer image; (2) extraction of spinal cord with sagittal image from the extracted vertebra; (3) selection of a series of coronal localizer images corresponding to various, involved portions of the extracted spinal cord with sagittal image; (4) generation of a composite coronal-plane image from the obtained coronal images; (5) extraction of spinal cord from the obtained composite image; (6) determination of oblique sagittal sections from the detected location and gradient of the extracted spinal cord. Cervical spine images obtained from 25 healthy volunteers were used for the study. A perceptual evaluation was performed by five experienced MRI operators. Good agreement between the automated and manual determinations was achieved. By use of the proposed scheme, average execution time was reduced from 39 seconds/case to 1 second/case. The results demonstrate that the proposed scheme can assist MRI operators in performing cervical spinal cord MRI exam accurately and rapidly.

  8. Examination of Inertial Sensor-Based Estimation Methods of Lower Limb Joint Moments and Ground Reaction Force: Results for Squat and Sit-to-Stand Movements in the Sagittal Plane.

    PubMed

    Kodama, Jun; Watanabe, Takashi

    2016-08-01

    Joint moment estimation by a camera-based motion measurement system and a force plate has a limitation of measurement environment and is costly. The purpose of this paper is to evaluate quantitatively inertial sensor-based joint moment estimation methods with five-link, four-link and three-link rigid body models using different trunk segmented models. Joint moments, ground reaction forces (GRF) and center of pressure (CoP) were estimated for squat and sit-to-stand movements in the sagittal plane measured with six healthy subjects. The five-link model and the four-link model that the trunk was divided at the highest point of the iliac crest (four-link-IC model) were appropriate for joint moment estimation with inertial sensors, which showed average RMS values of about 0.1 Nm/kg for all lower limb joints and average correlation coefficients of about 0.98 for hip and knee joints and about 0.80 for ankle joint. Average root mean square (RMS) errors of horizontal and vertical GRFs and CoP were about 10 N, 15 N and 2 cm, respectively. Inertial sensor-based method was suggested to be an option for estimating joint moments of the trunk segments. Inertial sensors were also shown to be useful for the bottom-up estimation method using measured GRFs, in which average RMS values and average correlation coefficients were about 0.06 Nm/kg and larger than about 0.98 for all joints.

  9. Examination of Inertial Sensor-Based Estimation Methods of Lower Limb Joint Moments and Ground Reaction Force: Results for Squat and Sit-to-Stand Movements in the Sagittal Plane

    PubMed Central

    Kodama, Jun; Watanabe, Takashi

    2016-01-01

    Joint moment estimation by a camera-based motion measurement system and a force plate has a limitation of measurement environment and is costly. The purpose of this paper is to evaluate quantitatively inertial sensor-based joint moment estimation methods with five-link, four-link and three-link rigid body models using different trunk segmented models. Joint moments, ground reaction forces (GRF) and center of pressure (CoP) were estimated for squat and sit-to-stand movements in the sagittal plane measured with six healthy subjects. The five-link model and the four-link model that the trunk was divided at the highest point of the iliac crest (four-link-IC model) were appropriate for joint moment estimation with inertial sensors, which showed average RMS values of about 0.1 Nm/kg for all lower limb joints and average correlation coefficients of about 0.98 for hip and knee joints and about 0.80 for ankle joint. Average root mean square (RMS) errors of horizontal and vertical GRFs and CoP were about 10 N, 15 N and 2 cm, respectively. Inertial sensor-based method was suggested to be an option for estimating joint moments of the trunk segments. Inertial sensors were also shown to be useful for the bottom-up estimation method using measured GRFs, in which average RMS values and average correlation coefficients were about 0.06 Nm/kg and larger than about 0.98 for all joints. PMID:27490544

  10. The Relationships Between the Center of Mass Position and the Trunk, Hip, and Knee Kinematics in the Sagittal Plane: A Pilot Study on Field-Based Video Analysis for Female Soccer Players

    PubMed Central

    Sasaki, Shogo; Nagano, Yasuharu; Kaneko, Satoshi; Imamura, Shoichiro; Koabayshi, Takuma; Fukubayashi, Toru

    2015-01-01

    Athletes with non-contact anterior cruciate ligament tears have common features in the sagittal plane; namely, the body’s center of mass (COM) is located posterior to the base of support, the trunk and knee joints are extended, and the hip angle is flexed. However, the relationships among these variables have not been assessed in field-based movements. This study sought to determine relationships between distances from the COM to the base of support and the trunk, hip, and knee positions in women while playing soccer. Sixty events (29 single-leg landing and 31 single-leg stopping events) were analyzed using two-dimensional video analysis. The relationships among the measurement variables were determined using the Pearson’s product-moment correlation coefficient, and stepwise multiple linear regression models were used to explore the relationships between the COM position and the kinematic variables. The distance from the COM to the base of support displayed a moderate negative relationship with the trunk angle (r = −0.623, p < .0001, r2 = 0.388) and a strong positive relationship with the limb angle (r = 0.869, p < .0001, r2 = 0.755). The limb, knee, and trunk angles were selected in the best regression model (adjusted r2 = 0.953, p < .0001, f2 = 20.277). These findings suggest that an increased trunk angle and a decreased limb angle at initial contact are associated with a safer COM position. Neuromuscular training may be useful for controlling the trunk and lower limb positions during dynamic activities. PMID:25964811

  11. Rebound Deformity After Growth Modulation in Patients With Coronal Plane Angular Deformities About the Knee: Who Gets It and How Much?

    PubMed

    Leveille, Lise A; Razi, Ozan; Johnston, Charles E

    2017-05-18

    With observed success and increased popularity of growth modulation techniques, there has been a trend toward use in progressively younger patients. Younger age at growth modulation increases the likelihood of complete deformity correction and need for implant removal before skeletal maturity introducing the risk of rebound deformity. The purpose of this study was to quantify magnitude and identify risk factors for rebound deformity after growth modulation. We performed a retrospective review of all patients undergoing growth modulation with a tension band plate for coronal plane deformity about the knee with subsequent implant removal. Exclusion criteria included completion epiphysiodesis or osteotomy at implant removal, ongoing growth modulation, and <1 year radiographic follow-up without rebound deformity. Mechanical lateral distal femoral angle, mechanical medial proximal tibial angle, hip-knee-ankle angle (HKA), and mechanical axis station were measured before growth modulation, before implant removal, and at final follow-up. In total, 67 limbs in 45 patients met the inclusion criteria. Mean age at growth modulation was 9.8 years (range, 3.4 to 15.4 y) and mean age at implant removal was 11.4 years (range, 5.3 to 16.4 y). Mean change in HKA after implant removal was 6.9 degrees (range, 0 to 23 degrees). In total, 52% of patients had >5 degrees rebound and 30% had >10 degrees rebound in HKA after implant removal. Females below 10 years and males below 12 years at time of growth modulation had greater mean change in HKA after implant removal compared with older patients (8.4 vs. 4.7 degrees, P=0.012). Patients with initial deformity >20 degrees had an increased frequency of rebound >10 degrees compared with patients with less severe initial deformity (78% vs. 22%, P=0.002). Rebound deformity after growth modulation is common. Growth modulation at a young age and large initial deformity increases risk of rebound. However, rebound does not occur in all at risk

  12. Sagittal Spine Length Measurement: A Novel Technique to Assess Growth of the Spine.

    PubMed

    Spurway, Alan J; Chukwunyerenwa, Chukwudi K; Kishta, Waleed E; Hurry, Jennifer K; El-Hawary, Ron

    2016-09-01

    The accuracy and repeatability of a novel sagittal spine length (SSL) radiographic measurement was examined using photographic and radiographic imaging. To validate the new SSL technique for measuring growth in early-onset scoliosis (EOS) patients. Current assessment of patient growth undergoing growth-friendly surgical treatment for EOS is the use of serial vertical spine height measurements (VH) on coronal radiographs. Spine-based distraction implants are able to control the coronal plane deformity of scoliosis, but exhibit a "law of diminishing returns" in the impact of each follow-up lengthening surgery. As these treatments are kyphogenic, we hypothesize that the increase in kyphosis is, in fact, growth out of plane, not captured by standard spine height measurements. Measurement accuracy was assessed using 6 spine model alignments and clinical radiographs of 23 retrospective EOS patients. Inter- and intrarater reliabilities were assessed using interclass coefficient (ICC) analyses. The discrepancy between the VH and SSL was also investigated. The model assessment showed excellent accuracy, with a 1.54 mm (SD: 1.07, range: 0.03-3.14, p = .226) mean error and mean ICCs of 0.999. As the kyphosis increased, a progressive difference between the phantom VH and SSL was observed. Interrater reliability ICCs of the clinical radiographs averaged 0.981 and 0.804, whereas intrarater reliabilities averaged 0.966 and 0.826, for the coronal and sagittal radiographs, respectively. Mean clinical SSLs were 177.5 mm (SD: 28.5, range: 114.3-250.3), whereas the VH averaged 161.6 mm (SD: 31.8, range: 58.5-243.0), resulting in a 16.0-mm (SD: 16.7, range: 0.3-90.3, p < .0001) difference between the two measurements with a progressive difference as the kyphosis increased. The novel SSL measurement is accurate, repeatable, and complements the current growth assessments for EOS treatments. Until sagittal spine lengths are taken into consideration, the "law of diminishing returns" should

  13. Sagittal alignment of the spine: What do you need to know?

    PubMed

    Diebo, Bassel G; Varghese, Jeffrey J; Lafage, Renaud; Schwab, Frank J; Lafage, Virginie

    2015-12-01

    Sagittal alignment, often misrepresented as sagittal balance, describes the ideal and "normal" alignment in the sagittal plane, resulting from the interplay between various organic factors. Any pathology that alters this equilibrium instigates sagittal malalignment and its compensatory mechanisms. As a result, sagittal malalignment is not limited to adult spinal deformity; its pervasiveness extends through most spinal disorders. While further research is developing, the literature reports clinically relevant radiographic parameters that have significant relationships with patient-reported outcomes. This article aims to provide a pragmatic review of sagittal plane analysis. At the end of this review, the reader should be able to analyze the sagittal plane of the spine, identify compensatory mechanisms, and choose patient-specific alignment targets. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Axial plane analysis of Lenke 1A adolescent idiopathic scoliosis as an aid to identify curve characteristics.

    PubMed

    Atmaca, Halil; Inanmaz, Mustafa Erkan; Bal, Emre; Caliskan, Islam; Kose, Kamil Cagri

    2014-10-01

    Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional (3D) deformity of the spine involving deviations in the frontal plane, modifications of the sagittal profile, and rotations in the transverse plane. Although Lenke classification system is based on 2D radiographs and includes sagittal thoracic and coronal lumbar modifiers, Lenke et al. suggested inclusion of axial thoracic and lumbar modifiers in the analysis. To analyze axial plane of Lenke 1A curves to identify curve characteristics. Retrospective study. Seventy patients (49 women, 21 men) with Lenke Type 1A idiopathic scoliosis were analyzed. Coronal, sagittal, and axial parameters were measured from plain radiographs that were obtained at initial medical examination of the patients. Coronal and sagittal plane and whole spine segmental vertebra rotations from thoracic 1 to lumbar 5 were evaluated in 70 AIS patients with Lenke 1A curves by using Drerup method. Three different subgroups were identified according to magnitude and direction of lower end vertebra (LEV) rotation. In Group 1 (Lenke 1A1), the direction of LEV rotation was same with other vertebrae in the main curve and the magnitude of the LEV rotation was less than -0.5°. In Group 2 (Lenke 1A2), the rotation of LEV was between -0.5° and 0.5° and so was accepted as neutral. In Group 3 (Lenke 1A3), the rotation of LEV had opposite direction with vertebrae in the main curve and the magnitude of LEV rotation was more than 0.5°. The mean thoracic Cobb angle of patients with Lenke 1A idiopathic scoliosis was 51.1° (range 37°-80°), whereas the mean lumbar Cobb angle was 16.4° (range 0°-32°). The mean angle of trunk rotation of the patients was 5.7° (range 1°-16°). In terms of maximum thoracic vertebra rotation, the mean rotation angle of Lenke 1A idiopathic curves was -18.9° (range -(9.8°-44.7°)). The mean maximum lumbar vertebra rotation was 4.5° (range -7.2° to 15.1°). Addition of axial plane analysis to conventional

  15. Measuring Coronal Magnetic Fields with Coronal Emission Line Polarimetry

    NASA Astrophysics Data System (ADS)

    Lin, H.

    2003-12-01

    Magnetic field is the dominating field in the solar corona, responsible for the majestic coronal structures and dynamic events. However, no direct measurements of the coronal magnetic fields are routinely available and we can only infer the coronal magnetic field structures from observed intensity images. Although several methods for the diagnostics of coronal magnetic fields have been demonstrated, measurement of the coronal magnetic fields remains a very challenging observational task. This paper reports on a concerted effort at the Institute for Astronomy (IfA) to establish routine vector coronal magnetic field measurement capabilities using spectropolarimetric observation of the near infrared Fe XIII 1074.7 nm coronal emission line. The IfA effort includes observations of two-dimensional circular polarization maps of the emission line which carry information about the coronal magnetic field strength. High resolution observation of the linear polarization maps which yield the projected direction of the coronal magnetic field in the plane of the sky will also be obtained. The latest results from these experiments will be presented.

  16. Sagittal Balance in Adolescent Idiopathic Scoliosis

    PubMed Central

    Xu, Xi-Ming; Wang, Fei; Zhou, Xiao-Yi; Liu, Zi-Xuan; Wei, Xian-Zhao; Bai, Yu-Shu; Li, Ming

    2015-01-01

    Abstract The relationship between spinal sagittal alignment and pelvic parameters is well known in adolescent idiopathic scoliosis. However, few studies have reported the sagittal spinopelvic relationship after selective posterior fusion of thoracolumbar/lumbar (TL/L) curves. We evaluated the relationship between spinal sagittal alignment and the pelvis, and analyzed how the pelvic sagittal state is adjusted in Lenke type 5C patients. We conducted a retrospective study of 36 patients with Lenke type 5C curves who received selective posterior TL/L curve fusion. Coronal and spinopelvic sagittal parameters were pre and postoperatively compared. Pearson coefficients were used to analyze the correlation between all spinopelvic sagittal parameters before and after surgery. We also evaluated 3 pelvic morphologies (anteverted, normal, and retroverted) before and after surgery. Preoperatively, the mean pelvic incidence was 46.0°, with a pelvic tilt and sacral slope (SS) of 8.2° and 37.8°, respectively, and 25% (9/36) of patients had an anteverted pelvis, whereas the other 75% had a normal pelvis. Postoperatively, 42% (15/36) of patients had a retroverted pelvis, 53% (19/36) had a normal pelvis, and 2 patients had an anteverted pelvis. Logistic regression analyses yielded 2 factors that were significantly associated with the risk for a postoperative unrecovered anteverted pelvis, including increased lumbar lordosis (LL) (odds ratio [OR] 4.8, P = 0.029) and increased SS (OR 5.6, P = 0.018). Four factors were significantly associated with the risk of a postoperative newly anteverted pelvis, including LL at the final follow-up (OR 6.9, P = 0.009), increased LL (OR 8.9, P = 0.003), LL below fusion (OR 9.4, P = 0.002), and increased SS (OR 11.5, P = 0.001). The pelvic state may be adjusted after selective posterior TL/L curve fusion in Lenke 5C adolescent idiopathic scoliosis patients. It is difficult to improve an anteverted pelvis in patients who have

  17. Plane reconstruction ultrasound tomography device

    SciTech Connect

    Hassler, D.

    1984-10-23

    An ultrasound tomography device for scanning an object under examination from a plurality of directions. Coronal slice images of the plane areas near or at the female breast wall are obtained. Ultrasound lobes from ultrasound transducers are electronically directed or mechanically positioned to obliquely strike the coronal slice located at or near the breast wall. A full image of the coronal slice plane is reconstructed through section by section combination of the images obtained from the several ultrasound lobes.

  18. 3D knee segmentation based on three MRI sequences from different planes.

    PubMed

    Zhou, L; Chav, R; Cresson, T; Chartrand, G; de Guise, J

    2016-08-01

    In clinical practice, knee MRI sequences with 3.5~5 mm slice distance in sagittal, coronal, and axial planes are often requested for the knee examination since its acquisition is faster than high-resolution MRI sequence in a single plane, thereby reducing the probability of motion artifact. In order to take advantage of the three sequences from different planes, a 3D segmentation method based on the combination of three knee models obtained from the three sequences is proposed in this paper. In the method, the sub-segmentation is respectively performed with sagittal, coronal, and axial MRI sequence in the image coordinate system. With each sequence, an initial knee model is hierarchically deformed, and then the three deformed models are mapped to reference coordinate system defined by the DICOM standard and combined to obtain a patient-specific model. The experimental results verified that the three sub-segmentation results can complement each other, and their integration can compensate for the insufficiency of boundary information caused by 3.5~5 mm gap between consecutive slices. Therefore, the obtained patient-specific model is substantially more accurate than each sub-segmentation results.

  19. Sagittal spinal pelvic alignment.

    PubMed

    Klineberg, Eric; Schwab, Frank; Smith, Justin S; Gupta, Munish C; Lafage, Virginie; Bess, Shay

    2013-04-01

    The goal of any ambulatory patient is to maintain a horizontal gaze with the least amount of energy expenditure. With progressive deformity, and in particular sagittal malalignment, significant compensatory mechanisms must be used to achieve this goal. Each pelvis dictates the amount of lumbar lordosis required through its morphometric parameter pelvic incidence. The pelvis may compensate for decreasing lumbar lordosis (eg, age, flat back deformity) by retroverting and increasing pelvic tilt and decreasing the sacral slope. Underappreciation for these spinopelvic compensatory mechanisms leads to surgical under-correction, iatrogenic flat back and poor clinical outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Estimation of tendon-plane orientation within human masseter muscle from reconstructed magnetic resonance images.

    PubMed

    Lam, E W; Hannam, A G; Christiansen, E L

    1991-01-01

    The human masseter is a powerful multipennate jaw elevator with complex internal architecture. The three-dimensional disposition of tendon planes within the muscle is thought to be an important determinant of function. We selected five adult subjects and used cephalometric radiography, magnetic resonance imaging and graphical, three-dimensional reconstruction to describe the organization of these planes within the muscle. Putative tendon planes were fitted to the surfaces of the three-dimensional reconstructions, and these were related to the mid-sagittal plane in the coronal and transverse views. To confirm whether putative planes disclosed by magnetic resonance represented true anatomical entities, a fresh human cadaver head was imaged and the magnetic resonance slices were compared with cryosections obtained in the same planes. Tendon-plane angulation appeared to be related to ramal length and lower face height measured cephalometrically. In the transverse view, the tendon planes appeared roughly to follow the angulations of the zygomatic arch and the lateral face of the mandibular ramus. These findings suggest that the angulation of tendon planes, and possibly pennation angles, are different depending on the viewing angle. Rather than reporting pennation angle as a single angle, alpha, which has been the convention, it may be more appropriate to express it as a three-dimensional angle relative to the normal of a particular tendon plane. The inference is that muscle fibres inserting on either side of a central tendon may need to develop different tensile forces if translation is to occur directly along the tendon axis.

  1. Delineation of vertebral area on the coronal plane using three-dimensional ultrasonography advanced volume contrast imaging (VCI) Omni view: intrarater reliability and agreement using standard mouse, high definition mouse, and pen-tablet.

    PubMed

    Araujo Júnior, Edward; Martinez, Luis Henrique; Simioni, Christiane; Martins, Wellington P; Nardozza, Luciano M; Moron, Antonio F

    2012-09-01

    To assess the fetal lumbosacral spine by three-dimensional (3D) ultrasonography using volume contrast imaging (VCI) omni view method and compare reproducibility and agreement between three different measurement techniques: standard mouse, high definition mouse and pen-tablet. A comparative and prospective study with 40 pregnant women between 20 and 34 + 6 weeks was realized. 3D volume datasets of the fetal spine were acquired using a convex transabdominal transducer. Starting scan plane was the coronal section of fetal lumbosacral spine by VCI-C function. Omni view manual trace was selected and a parallel plane of fetal spine was drawn including interest region. Intraclass correlation coefficient (ICC) was used for reproducibility analysis. The relative difference between three used techniques was compared by chi-square test and Fischer test. Pen-tablet showed better reliability (ICC=0.987). In the relative proportion of differences, this was significantly higher for the pen-tablet (82.14%; p<0.01). In paired comparison, the relative difference was significantly greater for the pen-tablet (p<0.01). The pen-tablet showed to be the most reproductive and concordant method in the measurement of body vertebral area of fetal lumbosacral spine by 3D ultrasonography using the VCI.

  2. Automatic Recognition of Fetal Facial Standard Plane in Ultrasound Image via Fisher Vector

    PubMed Central

    Lei, Baiying; Tan, Ee-Leng; Chen, Siping; Zhuo, Liu; Li, Shengli; Ni, Dong; Wang, Tianfu

    2015-01-01

    Acquisition of the standard plane is the prerequisite of biometric measurement and diagnosis during the ultrasound (US) examination. In this paper, a new algorithm is developed for the automatic recognition of the fetal facial standard planes (FFSPs) such as the axial, coronal, and sagittal planes. Specifically, densely sampled root scale invariant feature transform (RootSIFT) features are extracted and then encoded by Fisher vector (FV). The Fisher network with multi-layer design is also developed to extract spatial information to boost the classification performance. Finally, automatic recognition of the FFSPs is implemented by support vector machine (SVM) classifier based on the stochastic dual coordinate ascent (SDCA) algorithm. Experimental results using our dataset demonstrate that the proposed method achieves an accuracy of 93.27% and a mean average precision (mAP) of 99.19% in recognizing different FFSPs. Furthermore, the comparative analyses reveal the superiority of the proposed method based on FV over the traditional methods. PMID:25933215

  3. Cervical Sagittal Alignment in Extensive Fusions for Lenke 3C and 6C Scoliosis: The Effect of Upper Instrumented Vertebra.

    PubMed

    Yanik, Hakan Serhat; Ketenci, Ismail Emre; Erdem, Sevki

    2017-03-15

    A retrospective analysis of cervical sagittal alignment (CSA) in Lenke 3C and 6C adolescent idiopathic scoliosis (AIS). The aim of this study was to evaluate CSA according to upper instrumented vertebra (UIV) level. Hypokyphotic effect of extensive fusions of Lenke 3C and 6C curves on thoracic spine leads to kyphotic changes in cervical region. No study has evaluated the CSA in these patients according to UIV level. A total of 55 Lenke 3C and 6C AIS patients who underwent posterior fusion with pedicle screw instrumentation were recruited in this study. Patients were divided into three groups according to UIV level, which was determined preoperatively on the basis of shoulder balance. There were 22, 19, and 14 patients in T2, T3, and T4 groups, respectively. Three groups were similar according to demographic and preoperative coronal and sagittal alignment parameters. Patients were compared at two-year follow-up according to radiographic changes in coronal and sagittal planes. Main sagittal parameters were C2-C7 cervical lordosis (CL), T1 slope, T1-T5, and T5-T12 kyphosis. Clinical outcomes were assessed using scoliosis research society (SRS)-22 and short form (SF)-36 questionnaires. In all patients, C2-C7 CL, T5-T12 kyphosis, and T1 slope significantly decreased postoperatively (P < 0.05). The amount of decrease was similar between groups. T1-T5 kyphosis did not change significantly in all groups. Twenty-seven patients had postoperative cervical kyphosis (CK). Thirteen of them had preoperative CL and 14 had CK. Twenty-eight of 41 patients with preoperative CL remained in lordotic CSA postoperatively. SRS-22 and SF-36 scores did not change significantly after the surgery. In Lenke 3C and 6C AIS, postoperative CSA is independent from UIV level. Decreased CL is mainly caused by T5-T12 and T1 slope decrease. In order to achieve level shoulders, fusion can be extended to appropriate upper level, without increased risk of CK. 4.

  4. ARTICULATOR-RELATED REGISTRATION AND ANALYSIS OF SAGITTAL CONDYLAR INCLINATION.

    PubMed

    Cimić, Samir; Simunković, Sonja Kraljević; Suncana Simonić Kocijan; Matijević, Jurica; Dulcić, Niksa; Catić, Amir

    2015-12-01

    The purpose of this investigation was to study sagittal condylar inclination values within a uniform sample (Angle class I occlusion) using 'articulator-related registration' and Camper's plane as a reference plane. The study was performed on a sample of 58 Angle class I subjects (mean age 25.1, SD 3.1). Measurements were performed with an ultrasonic jaw tracking device with six degrees of freedom. After a paraocclusal tray was fixed in the mouth, each subject had to make three protrusive movements and three right and left laterotrusive movements. From protrusive movements the software of the device automatically calculated the left and the right sagittal condylar inclination values used for setting of the articulator. The mean sagittal condylar inclinationvalue was 41.0° (SD 10.5) for the right joint and 40.7° (SD 9.8) for the left joint. The maximum value was 65.0° for the right and 68.6° for the left joint, and the minimum value was 13.7° for the right and 21.7° for the left joint. The results of this study suggested the average articulator setting for sagittal condylar inclination for fully dentate adult subjects to be 40° in relation to Camper's plane. This is especially important for the articulators that are set up in relation to Camper's plane.

  5. Coronation Chemicals

    NASA Image and Video Library

    2012-08-22

    This is the first laser spectrum from the ChemCam instrument on NASA Curiosity rover, sent back from Mars on Aug. 19, 2012, showing emission lines from different elements present in the target, a rock near the rover landing site dubbed Coronation.

  6. Geometric influence of the sagittal and vertical apical base relationship on the ANB angle.

    PubMed

    Sadat-Khonsari, Reza; Dathe, Henning; Knösel, Michael; Hahn, Wolfram; Kubein-Meesenburg, Dietmar; Bauss, Oskar

    2009-03-01

    The objective of this study consisted in determining the variability of the ANB angle in relation to the position of the A- and B-points in the sagittal vertical plane. Using a theoretical model, we varied the position of the cephalometric points A and B in the sagittal vertical plane while its sagittal relationship was kept constant (Wits value = 0 mm). For this purpose, seven lines were erected perpendicular to the occlusal plane on a lateral cephalogram. The position of points A and B were determined on each of the vertical lines by calculating one anterior and one posterior angle in each case. In this way, the positions of all A- and B-points were clearly defined in the sagittal vertical plane. The characteristic of the ANB angle in the sagittal vertical plane was graphically represented by determining both points A and B using two angles instead of one. This revealed that the ANB angle for the same sagittal base relationship was characterized by major variations depending on the position of the A- and B-points in relation to the anterior cranial base. The larger the SNA and SNB angles were, the larger the corresponding ANB angle. At the same time, the absolute value of ANB increased with the length of the vertical distance between the points A and B. The ANB angle is strongly influenced by geometric factors. Accurate diagnosis of the sagittal base relationship should thus take the individual character of the ANB angle into account.

  7. Coronal Holes.

    PubMed

    Cranmer, Steven R

    Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed solar wind. This paper reviews measurements of the plasma properties in coronal holes and how these measurements are used to reveal details about the physical processes that heat the solar corona and accelerate the solar wind. It is still unknown to what extent the solar wind is fed by flux tubes that remain open (and are energized by footpoint-driven wave-like fluctuations), and to what extent much of the mass and energy is input intermittently from closed loops into the open-field regions. Evidence for both paradigms is summarized in this paper. Special emphasis is also given to spectroscopic and coronagraphic measurements that allow the highly dynamic non-equilibrium evolution of the plasma to be followed as the asymptotic conditions in interplanetary space are established in the extended corona. For example, the importance of kinetic plasma physics and turbulence in coronal holes has been affirmed by surprising measurements from the UVCS instrument on SOHO that heavy ions are heated to hundreds of times the temperatures of protons and electrons. These observations point to specific kinds of collisionless Alfvén wave damping (i.e., ion cyclotron resonance), but complete theoretical models do not yet exist. Despite our incomplete knowledge of the complex multi-scale plasma physics, however, much progress has been made toward the goal of understanding the mechanisms ultimately responsible for producing the observed properties of coronal holes.

  8. Properties and Radial Trends of Coronal Mass Ejecta and Their Associated Shocks Observed by Ulysses in the Ecliptic Plane. Appendix 2; Repr. from Journal of Geophysical Research, v. 105, 2000 p 12,617-12,626

    NASA Technical Reports Server (NTRS)

    Riley, Pete; Gosling, J. T.; McComas, D. J.; Forsyth, R. J.

    2001-01-01

    In this paper, magnetic and plasma measurements are used to analyze 17 interplanetary coronal mass ejections (CMEs) identified by Ulysses during its in-ecliptic passage to Jupiter. We focus on the expansion characteristics of these CMEs (as inferred from the time rate of change of the velocity profiles through the CMEs) and the properties of 14 forward shocks unambiguously associated with these CMEs. We highlight radial trends from 1 to 5.4 AU. Our results indicate that the CMEs are generally expanding at all heliocentric distances. With regard to the shocks preceding these ejecta, we note the following: (1) There is a clear tendency for the shock speed (in the upstream frame of reference) to decrease with increasing heliocentric distance as the CMEs transfer momentum to the ambient solar wind and slow down; (2) 86% of the shock fronts are oriented in the ecliptic plane such that their normals point westward (i.e., in the direction of planetary motion about the Sun), (3) 86% of the shocks are propagating toward the heliographic equator; and (4) no clear trend was found in the strength of the shocks versus heliocentric distance. These results are interpreted using simple dynamical arguments and are supported by fluid and magnetohydrodynamic (MHD) simulations.

  9. Properties and Radial Trends of Coronal Mass Ejecta and Their Associated Shocks Observed by Ulysses in the Ecliptic Plane. Appendix 2; Repr. from Journal of Geophysical Research, v. 105, 2000 p 12,617-12,626

    NASA Technical Reports Server (NTRS)

    Riley, Pete; Gosling, J. T.; McComas, D. J.; Forsyth, R. J.

    2001-01-01

    In this paper, magnetic and plasma measurements are used to analyze 17 interplanetary coronal mass ejections (CMEs) identified by Ulysses during its in-ecliptic passage to Jupiter. We focus on the expansion characteristics of these CMEs (as inferred from the time rate of change of the velocity profiles through the CMEs) and the properties of 14 forward shocks unambiguously associated with these CMEs. We highlight radial trends from 1 to 5.4 AU. Our results indicate that the CMEs are generally expanding at all heliocentric distances. With regard to the shocks preceding these ejecta, we note the following: (1) There is a clear tendency for the shock speed (in the upstream frame of reference) to decrease with increasing heliocentric distance as the CMEs transfer momentum to the ambient solar wind and slow down; (2) 86% of the shock fronts are oriented in the ecliptic plane such that their normals point westward (i.e., in the direction of planetary motion about the Sun), (3) 86% of the shocks are propagating toward the heliographic equator; and (4) no clear trend was found in the strength of the shocks versus heliocentric distance. These results are interpreted using simple dynamical arguments and are supported by fluid and magnetohydrodynamic (MHD) simulations.

  10. Hinged-Knee External Fixator Used to Reduce and Maintain Subacute Tibiofemoral Coronal Subluxation.

    PubMed

    Geiger, Erik J; Arzeno, Alexander H; Medvecky, Michael J

    Dislocation of the knee is a rare phenomenon that is becoming increasingly recognized with the expansion of its definition to include knees presenting with multiligament compromise. Hinged external fixators are now considered a viable supplementary treatment option in the management of acute ligament repair or reconstruction but their use in the management of subacute or chronic tibiofemoral dislocations or subluxations is less well defined. We report a case of a hinged-knee external fixator used to facilitate and maintain reduction of a chronic coronal tibial subluxation that presented after repair of an acute knee dislocation with lateral ligament injury secondary to a motor vehicle accident. At 5-year follow-up, the patient treated with hinged external fixation had a stable joint, was able to tolerate regular aerobic exercise, was minimally symptomatic, and did not require more extensive ligament reconstruction. Although there are reports on postoperative use of hinged external fixation to maintain the reduction of chronic or subacute knee dislocations in the sagittal plane after cruciate ligament repair, there are no reports on management of subacute tibiofemoral subluxation in the coronal plane.

  11. Changes in sagittal component alignment alters patellar kinematics in TKA: an in vitro study.

    PubMed

    Keshmiri, Armin; Springorum, Hans Robert; Baier, Clemens; Zeman, Florian; Grifka, Joachim; Maderbacher, Günther

    2016-03-01

    Patellar maltracking due to incorrect component alignment is considered as a main reason for anterior knee pain after total knee arthroplasty (TKA). In contrast to coronal and axial component placement, the influence of sagittal component alignment on patellar kinematics has not been investigated so far. In ten lower cadaveric limbs, TKAs were implanted using a commercial computer navigation system. In six knees, the femoral component was aligned in 5° and in four knees in 0° of flexion, respectively. Patellar kinematics were registered by means of a computer navigation system using an additional patella tracking array and correlated with femoral and tibial sagittal component alignment. Sagittal component alignment significantly altered patellar mediolateral shift (p < 0.05). In contrast, patellar epicondylar distance, rotation and tilt were not significantly influenced. Sagittal component alignment in TKA has a major impact on patellar kinematics and should therefore be considered while addressing tibiofemoral kinematics intraoperatively.

  12. Overjet as a predictor of sagittal skeletal relationships.

    PubMed

    Zupancic, S; Pohar, M; Farcnik, F; Ovsenik, Maja

    2008-06-01

    Skeletal relationships in the sagittal plane do not always correspond with dental relationships. The aim of this study was to determine in which type of malocclusion the correlation between overjet and skeletal sagittal parameters assessed by lateral cephalogram analysis is the highest. The extent to which overjet can predict skeletal relationships in the sagittal plane was also assessed. Eighty-three subjects fulfilled the inclusion criteria (40 males and 43 females, mean age 16.3 +/- 4.3 years). Overjet was measured on study casts and sagittal skeletal relationships were analysed on lateral cephalograms. ANB angle, Wits appraisal, and convexity at point A were determined. Mean values and standard deviations of measured parameters were calculated for Class I, Class II division 1, and Class III malocclusion subjects. Correlation between overjet measured on study casts and sagittal skeletal parameters measured on lateral cephalogram was calculated. Overjet as a predictor of skeletal relationships was assessed by means of linear regression analysis. A statistically significant positive correlation (P < 0.01) was found between the values of overjet and ANB (r = 0.690), overjet and Wits appraisal (r = 0.750), and overjet and convexity at point A (r = 0.608) when assessing the whole sample. When linear regression between overjet and cephalometric parameters was assessed separately in Class I, Class II division 1, and Class III malocclusion subjects, the percentage of variability was statistically significant in just four pairs. The findings show that overjet is a good predictor of sagittal relationship only in subjects with a Class II division 1 malocclusion.

  13. [Sagittal balance of the spine and degenerative spondylolisthesis].

    PubMed

    Morel, E; Ilharreborde, B; Lenoir, T; Hoffmann, E; Vialle, R; Rillardon, L; Guigui, P

    2005-11-01

    Several reports have examined the pathophysiology of degenerative spondylolisthesis. Very little work has however been devoted to the influence of spinal balance in the sagittal plane in its pathogenesis. The purpose of this work was to present a descriptive analysis of pelvic and spinal sagittal balance in a cohort of seventy patients treated for degenerative spondylolisthesis and to compare findings with those established in a population of 250 volunteers. The goal was to deduct pathophysiological hypotheses and identify therapeutic implications. Seventy patients were included in this study. The following variables were noted: pelvic incidence and version, sacral slope, lumbar lordosis, thoracic kyphosis, T9 sagittal tilt and S1-S2 angle. These variables were measured on digitalized lateral views of the spine using a dedicated software (SpineView). Univariate analysis of the values obtained was performed to identify the variable distributions. Multivariate analysis was applied to study the relationships between these variables and to better define perturbations of spinal balance in the anteroposterior plane. The findings were compared with those obtained in a control population. One of the essential characteristics of the cohort of patients with degenerative spondylolisthesis was the presence of an exaggerated pelvic incidence (62.6 degrees versus 54.7 degrees in the control population). The most significant determinants of T9 sagittal tilt (which reflects sagittal balance) were: pelvic version, pelvic incidence, lumbar lordosis, and L4-S1 local lordosis. One-third of our patients presented posterior tilt due to exaggerated thoracic kyphosis. The high pelvic incidence, via hyperlordosis and increased pelvic version, could be one of the factors favoring degenerative disease of the spinal unit. This work enabled us to better describe sagittal balance in patients with degenerative spondylolisthesis and to propose hypotheses concerning the underlying mechanism of

  14. The influence of elastic orthotic belt on sagittal profile in adolescent idiopathic thoracic scoliosis: a comparative radiographic study with Milwaukee brace.

    PubMed

    Jiang, Jun; Qiu, Yong; Mao, Saihu; Zhao, Qinghua; Qian, Bangping; Zhu, Feng

    2010-09-23

    The effectiveness of bracing on preventing curve progression in coronal plane for mild and moderate adolescent idiopathic scoliosis (AIS) patients has been confirmed by previous radiographic researches. However, a hypokyphotic effect on the sagittal plane has been reported by a few studies. A relatively increasing number of AIS patients were noticed to wear a new kind of elastic orthotic belt for the treatments of scoliosis without doctors' instructions. We postulate the correcting mechanism of this new appliance may cause flattening of the spine. To our knowledge, no study has investigated the effects of this new orthosis on the sagittal profile of AIS patients. The aim of this study was to evaluate and compare the effects of elastic orthotic belt and Milwaukee brace on the sagittal alignment in AIS patients. Twenty-eight female AIS patients with mild or moderate thoracic curves were included in this study. Standing full-length lateral radiographs were obtained in three conditions: natural standing posture without any treatment, with elastic orthotic belt and with Milwaukee brace. Thoracic kyphosis (TK), lumber lordosis (LL) and pelvic incidence (PI) were measured and compared between the above three conditions. Both elastic orthotic belt and Milwaukee brace can lead to significant decrease of TK, however, the decrease of TK after wearing elastic orthotic belt is significantly larger than that after wearing Milwaukee brace. Compared with no treatment, LL was found to be significantly smaller after wearing Milwaukee brace, however, such significant decrease was not noted after wearing elastic orthotic belt. No significant changes were observed for the PI between 3 conditions. The elastic orthotic belt could lead to more severe thoracic hypokyphosis when compared with Milwaukee brace. This belt may not be a suitable conservative method for the treatment of mild and moderate AIS patients.

  15. Coronal and Prominence Plasmas

    NASA Technical Reports Server (NTRS)

    Poland, Arthur I. (Editor)

    1986-01-01

    Various aspects of solar prominences and the solar corona are discussed. The formation of prominences, prominence diagnostics and structure, prominence dissappearance, large scale coronal structure, coronal diagnostics, small scale coronal structure, and non-equilibrium/coronal heating are among the topics covered.

  16. Supra-acetabular line is better than supra-iliac line for coronal balance referencing-a study of perioperative whole spine X-rays in degenerative lumbar scoliosis and ankylosing spondylitis patients.

    PubMed

    Hey, Hwee Weng Dennis; Kim, Cheung-Kue; Lee, Won-Gyu; Juh, Hyung-Suk; Kim, Ki-Tack

    2017-06-20

    The aim of spinal deformity correction is to restore the spine's functional alignment by balancing it in both the sagittal and coronal planes. Regardless of posture, the ideal coronal profile is straight, and therefore readily assessable. This study compares two radiological methods to determine which better predicts postoperative standing coronal balance. We conducted a single-center, radiographic comparative study between 2011 and 2015. A total of 199 patients with a mean age of 55.1 years were studied. Ninety patients with degenerative lumbar scoliosis (DLS) and 109 ankylosing spondylitis (AS) were treated with posterior surgery during this period. Baseline clinical and radiographic parameters (sagittal and coronal) were recorded. Comparison was performed between the new supra-acetabular line (central sacral vertical line [CSVL1]) and conventional supra-iliac line (CSVL2) perpendicular methods of coronal balance assessment. These methods were also compared with the gold standard standing C7 plumb line. Each patient underwent standardized operative procedures and had perioperative spine X-rays obtained for assessment of spinal balance. Adjusted multivariate analysis was used to determine predictors of coronal balance. Significant differences in baseline characteristics (age, gender, and radiographic parameters) were found between patients with DLS and AS. CSVL1, CSVL2, and C7 plumb line differed in all the perioperative measurements. These three radiological methods showed a mean right coronal imbalance for both diagnoses in all pre-, intra-, and postoperative radiographs. The magnitude of imbalance was the greatest for CSVL2 followed by CSVL1 and subsequently the C7 plumb line. A larger discrepancy between CSVL and C7 plumb line measurements intraoperatively than those postoperatively suggests a postural effect on these parameters, which is greater for CSVL2. Multivariate analysis identified that in DLS, the preoperative C7 plumb line was predictive of its

  17. Patients with proximal junctional kyphosis requiring revision surgery have higher postoperative lumbar lordosis and larger sagittal balance corrections.

    PubMed

    Kim, Han Jo; Bridwell, Keith H; Lenke, Lawrence G; Park, Moon Soo; Song, Kwang Sup; Piyaskulkaew, Chaiwat; Chuntarapas, Tapanut

    2014-04-20

    Case control study. To evaluate risk factors in patients in 3 groups: those without proximal junctional kyphosis (PJK) (N), with PJK but not requiring revision (P), and then those with PJK requiring revision surgery (S). It is becoming clear that some patients maintain stable PJK angles, whereas others progress and develop severe PJK necessitating revision surgery. A total of 206 patients at a single institution from 2002 to 2007 with adult scoliosis with 2-year minimum follow-up (average 3.5 yr) were analyzed. Inclusion criteria were age more than 18 years and primary fusions greater than 5 levels from any thoracic upper instrumented vertebra to any lower instrumented vertebrae. Revisions were excluded. Radiographical assessment included Cobb measurements in the coronal/sagittal plane and measurements of the PJK angle at postoperative time points: 1 to 2 months, 2 years, and final follow-up. PJK was defined as an angle greater than 10°. The prevalence of PJK was 34%. The average age in N was 49.9 vs. 51.3 years in P and 60.1 years in S. Sex, body mass index, and smoking status were not significantly different between groups. Fusions extending to the pelvis were 74%, 85%, and 91% of the cases in groups N, P, and S. Instrumentation type was significantly different between groups N and S, with a higher number of upper instrumented vertebra hooks in group N. Radiographical parameters demonstrated a higher postoperative lumbar lordosis and a larger sagittal balance change, with surgery in those with PJK requiring revision surgery. Scoliosis Research Society postoperative pain scores were inferior in group N vs. P and S, and Oswestry Disability Index scores were similar between all groups. Patients with PJK requiring revision were older, had higher postoperative lumbar lordosis, and larger sagittal balance corrections than patients without PJK. Based on these data, it seems as though older patients with large corrections in their lumbar lordosis and sagittal balance

  18. Sagittal osteotomy inclination in medial open-wedge high tibial osteotomy.

    PubMed

    Lee, Seung-Yup; Lim, Hong-Chul; Bae, Ji Hoon; Kim, Jae Gyoon; Yun, Se-Hyeok; Yang, Jae-Hyuk; Yoon, Jung-Ro

    2017-03-01

    Unlike postoperative changes in posterior tibial slope after medial open-wedge high tibial osteotomy, sagittal osteotomy inclination has not been examined. It has been recommended that the osteotomy line in the sagittal plane be parallel to the medial posterior tibial slope. The purpose of this study was to determine the frequency of parallel osteotomy in medial open-wedge high tibial osteotomy. To determine the sagittal osteotomy inclination, the angle between the medial joint line and the osteotomy line was measured in the lateral radiograph. A positive angle value indicates that the osteotomy is anteriorly inclined relative to the medial posterior tibial slope. Correlation between the sagittal osteotomy inclination and posterior tibial slope was also evaluated. The mean sagittal osteotomy inclination was 15.1 ± 7.5°. The majority 87.1 % of knees showed an anterior-inclined osteotomy. There was a significantly positive correlation between the postoperative posterior tibial slope and the sagittal osteotomy inclination (r, 0.33; 95 % confidence interval (CI) 0.19-0.46; P < 0.001). The postoperative change in posterior tibial slope also showed a significantly positive correlation with the sagittal osteotomy inclination (r, 0.35; 95 % CI 0.21-0.47; P < 0.001). Although parallel osteotomy in the sagittal plane relative to the medial joint line was planned, only 12.9 % of cases achieved osteotomy parallel to the medial posterior tibial slope in the sagittal plane. Because of high rate of the anterior-inclined osteotomy and their correlations with posterior tibial slope, surgeons should make all efforts to perform parallel osteotomy relative to medial posterior tibial slope. IV.

  19. Geometry of solar coronal rays

    NASA Astrophysics Data System (ADS)

    Filippov, B. P.; Martsenyuk, O. V.; Platov, Yu. V.; Den, O. E.

    2016-02-01

    Coronal helmet streamers are the most prominent large-scale elements of the solar corona observed in white light during total solar eclipses. The base of the streamer is an arcade of loops located above a global polarity inversion line. At an altitude of 1-2 solar radii above the limb, the apices of the arches sharpen, forming cusp structures, above which narrow coronal rays are observed. Lyot coronagraphs, especially those on-board spacecrafts flying beyond the Earth's atmosphere, enable us to observe the corona continuously and at large distances. At distances of several solar radii, the streamers take the form of fairly narrow spokes that diverge radially from the Sun. This radial direction displays a continuous expansion of the corona into the surrounding space, and the formation of the solar wind. However, the solar magnetic field and solar rotation complicate the situation. The rotation curves radial streams into spiral ones, similar to water streams flowing from rotating tubes. The influence of the magnetic field is more complex and multifarious. A thorough study of coronal ray geometries shows that rays are frequently not radial and not straight. Coronal streamers frequently display a curvature whose direction in the meridional plane depends on the phase of the solar cycle. It is evident that this curvature is related to the geometry of the global solar magnetic field, which depends on the cycle phase. Equatorward deviations of coronal streamers at solar minima and poleward deviations at solar maxima can be interpreted as the effects of changes in the general topology of the global solar magnetic field. There are sporadic temporal changes in the coronal rays shape caused by remote coronal mass ejections (CMEs) propagating through the corona. This is also a manifestation of the influence of the magnetic field on plasma flows. The motion of a large-scale flux rope associated with a CME away from the Sun creates changes in the structure of surrounding field

  20. Human visual and vestibular heading perception in the vertical planes.

    PubMed

    Crane, Benjamin T

    2014-02-01

    Heading estimation has not previously been reported in the vertical planes. This is a potentially interesting issue because although distribution of neuronal direction sensitivities is near uniform for vertical headings, there is an overrepresentation of otolith organs sensitive to motion in the horizontal relative to the vertical plane. Furthermore, thresholds of horizontal motion perception are considerably lower than those of vertical motion which has the potential to bias heading perception. The current data from 14 human subjects (age 19 to 67) measured heading estimation in response to vestibular motion of 14 cm (28 cm/s) over a 360° of headings at 5° intervals. An analogous visual motion was tested in separate trials. In this study, earth and head vertical/horizontal were always aligned. Results demonstrated that the horizontal component of heading was overestimated relative to the vertical component for vestibular heading stimuli in the coronal (skew) and sagittal (elevation) planes. For visual headings, the bias was much smaller and in the opposite direction such that the vertical component of heading was overestimated. Subjects older than 50 had significantly worse precision and larger biases relative to that of younger subjects for the vestibular conditions, although visual heading estimates were similar. A vector addition model was fit to the data which explains the observed heading biases by the known distribution of otolith organs in humans. The greatly decreased precision with age is explained by the model with decreases in end organ numbers, and relatively greater loss of otoliths that are sensitive to vertical motion.

  1. Coronal alignment of patellofemoral arthroplasty.

    PubMed

    Thienpont, Emmanuel; Lonner, Jess H

    2014-01-01

    Patellofemoral arthroplasty (PFA) can yield successful results in appropriately selected patients. The varus-valgus position or coronal alignment of the trochlear implant is determined by how its transitional edges articulate with the condylar cartilage. Whilst variation in condylar anatomy will not influence the axis of the lower limb in PFA, it can impact on the Q-angle of the PF joint. The aim of this study was to analyze how the coronal alignment can be influenced by the choice of anatomical landmarks. Retrospective analysis of 57 PFAs with measurements of alignment from full leg radiographs. Coronal alignment following anterior condylar anatomy leads to a mean (SD) proximal valgus alignment of 100° (9°). Aligning the component with Whiteside's line gives a better alignment with less variance 89° (3°). A trochlear component with a higher Q-angle compensates for patellar maltracking if the condylar anatomy would tend to put the implant in a more proximal varus or neutral position. If the trochlear component is proximally aligned in valgus this may have the opposite effect. Aligning the trochlear component with the AP-axis in the coronal plane avoids maltracking and optimally utilizes the design features of the implant. Level III. © 2014 Elsevier B.V. All rights reserved.

  2. A comparison of cephalometric analyses for assessing sagittal jaw relationship.

    PubMed

    Gul-e-Erum; Fida, Mubassar

    2008-11-01

    To compare the seven methods of cephalometric analysis for assessing sagittal jaw relationship and to determine the level of agreement between them. Cross-sectional, analytical study. Dental Section, the Aga Khan University Hospital, Karachi, from January to December 2004. Seven methods, describing anteroposterior jaw relationships (A-B plane, ANB, Wits, AXB, AF-BF, FABA and Beta angle) were measured on the lateral cephalographs of 85 patients. Correlation analysis, using Cramer's V-test, was performed to determine the possible agreement between the pair of analyses. The mean age of the sample, comprising 35 males and 50 females was 15 years and 3 months. Statistically significant relationships were found among seven sagittal parameters with p-value < 0.001. Very strong correlation was found between AXB and AF-BF distance (r=0.924); and weak correlation between ANB and Beta angle (r=0.377). Wits appraisal showed the greatest coefficient of variability. Despite varying strengths of association, statistically significant correlations were found among seven methods for assessing sagittal jaw relationship. FABA and A-B plane may be used to predict the skeletal class in addition to the established ANB angle.

  3. Elongated Coronal Hole

    NASA Image and Video Library

    2016-03-24

    NASA Solar Dynamics Observatory shows a long coronal hole has rotated so that was temporarily facing right towards Earth Mar. 23-25, 2016. Coronal holes appear dark when viewed in some wavelengths of extreme ultraviolet light.

  4. Implications for Coronal Heating from Coronal Rain

    NASA Astrophysics Data System (ADS)

    Antolin, P.; Shibata, K.; Carlsson, M.; van der Voort, L. R.; Vissers, G.; Hansteen, V.

    2012-08-01

    Coronal rain is a phenomenon above active regions in which cool plasma condensations fall down from coronal heights. Numerical simulations of loops have shown that such condensations can naturally form in the case of footpoint concentrated heating through the “catastrophic cooling” mechanism. In this work we analize high resolution limb observations in Ca II H and Hα of coronal rain performed by Hinode/SOT and by Crisp of SST and derive statistical properties. We further investigate the link between coronal rain and the coronal heating mechanisms by performing 1.5-D MHD simulations of a loop subject to footpoint heating and to Alfvén waves generated in the photosphere. It is found that if a loop is heated predominantly from Alfvén waves coronal rain is inhibited due to the characteristic uniform heating they produce. Hence coronal rain can point both to the spatial distribution of the heating and to the agent of the heating itself, thus acting as a marker for coronal heating mechanisms.

  5. Pre- and postoperative spinopelvic sagittal balance in adolescent patients with lenke type 5 idiopathic scoliosis.

    PubMed

    Yang, Xi; Liu, Limin; Song, Yueming; Zhou, Chunguang; Zhou, Zhongjie; Wang, Lei; Wang, Liang

    2015-01-15

    A retrospective study. To investigate the preoperative spinopelvic sagittal alignment in Lenke 5 patients with adolescent idiopathic scoliosis (AIS), and analyze how it alters after posterior correction. The structural thoracolumbar or lumbar curve may change the local sagittal alignment thereby altering the sagittal balance in Lenke 5 patients with AIS. However, few studies have evaluated the spinopelvic sagittal alignment before and after the surgery in these patients. Forty-eight Lenke 5 patients with AIS who underwent posterior correction and fusion were included in this study. Preoperative and postoperative radiographs were reviewed measuring both the coronal and sagittal parameters. Three pelvic sagittal states (anteverted, normal, or retroverted) were evaluated according to the magnitude relationship of individual pelvic tilt with pelvic incidence (PI). Both the coronal and sagittal parameters between different pelvic sagittal states were compared. The alterations of these parameters by surgery would also be analyzed. The mean follow-up was 1.8 years. Preoperatively, the mean PI was 44.3° with a pelvic tilt of 4.1°. There was 48% patients showing the anteverted pelvis, whereas the remaining 52% showing normal. The patients with anteverted pelvis showed a smaller PI and more distal lower end vertebra than normal pelvis ones. Logistic regression analysis revealed PI (odds ratio [OR] = 0.62, P = 0.024) and lower end vertebra (OR = 2.1, P = 0.037) were significantly associated with the risk of developing anteverted pelvis. The pelvic tilt was significantly increased and 61% of patients with preoperative anteverted pelvis had recovered. Logistic regression analysis revealed PI (OR = 0.7, P = 0.034) and lower instrumented vertebra (OR = 6.5, P = 0.002) were significantly associated with the risk of postoperative uncovered of anteverted pelvis. Anteverted pelvis appears in almost half of Lenke 5 patients with AIS, especially in who have smaller PI or distal lower

  6. Coronal heating by waves

    NASA Technical Reports Server (NTRS)

    Hollweg, J. V.

    1983-01-01

    Alfven waves or Alfvenic surface waves carry enough energy into the corona to provide the coronal energy requirements. Coronal loop resonances are an appealing means by which large energy fluxes enter active region loops. The wave dissipation mechanism still needs to be elucidated, but a Kolmogoroff turbulent cascade is fully consistent with the heating requirements in coronal holes and active region loops.

  7. Motion Magnification in Coronal Seismology

    NASA Astrophysics Data System (ADS)

    Anfinogentov, Sergey; Nakariakov, Valery M.

    2016-11-01

    We introduce a new method for the investigation of low-amplitude transverse oscillations of solar plasma non-uniformities, such as coronal loops, individual strands in coronal arcades, jets, prominence fibrils, polar plumes, and other contrast features that have been observed with imaging instruments. The method is based on the two-dimensional dual-tree complex wavelet transform (DTℂWT). It allows us to magnify transverse, in the plane-of-the-sky, quasi-periodic motions of contrast features in image sequences. The tests performed on the artificial data cubes that imitated exponentially decaying, multi-periodic and frequency-modulated kink oscillations of coronal loops showed the effectiveness, reliability, and robustness of this technique. The algorithm was found to give linear scaling of the magnified amplitudes with the original amplitudes, provided these are sufficiently small. In addition, the magnification is independent of the oscillation period in a broad range of the periods. The application of this technique to SDO/AIA EUV data cubes of a non-flaring active region allowed for the improved detection of low-amplitude decay-less oscillations in the majority of loops.

  8. Sagittal back contour and craniofacial morphology in preadolescents.

    PubMed

    Lippold, Carsten; Segatto, Emil; Végh, András; Drerup, Burkhard; Moiseenko, Tatjana; Danesh, Gholamreza

    2010-03-01

    The aim of this study was to analyze the correlation ratios between the sagittal back contour (flèche cervicale and lombaire, trunk inclination) and selected parameters of craniofacial morphology in children. The patient sample consisted of 66 healthy children with a mean age of 11.2 years (SD 1.6 years), of which 34 were male (mean age 11.5 years, SD 1.3 years) and 32 were females (mean age 10.9 years, SD 1.9 years). The children were recruited during the preparation of the initial orthodontic treatment records. Craniofacial morphology was analyzed by six angular measurements: facial axis, mandibular plane angle, inner gonial angle, lower facial height, facial depth and maxilla position. Rasterstereography was used for reconstruction of the spinal back sagittal profile. From the profile flèche cervicale, flèche lombaire and trunk inclination were determined and the correlations with the craniofacial morphology were calculated (Pearson and Mann-Whitney U test). Significant correlations were found with respect to the inner gonial angle and the flèche cervicale, the mandibular plane angle and the flèche lombaire, the inner gonial angle and the flèche lombaire, and the angular lower facial height and the flèche lombaire, as well as the inner gonial angle and the trunk inclination. The craniofacial vertical growth pattern, presented by mandibular plane angle, inner gonial angle and the angular lower facial height, and the correlation to flèche cervicale and lombaire as well as trunk inclination reveal correlations between growth pattern and sagittal back contour.

  9. Sagittal back contour and craniofacial morphology in preadolescents

    PubMed Central

    Lippold, Carsten; Végh, András; Drerup, Burkhard; Moiseenko, Tatjana; Danesh, Gholamreza

    2009-01-01

    The aim of this study was to analyze the correlation ratios between the sagittal back contour (flèche cervicale and lombaire, trunk inclination) and selected parameters of craniofacial morphology in children. The patient sample consisted of 66 healthy children with a mean age of 11.2 years (SD 1.6 years), of which 34 were male (mean age 11.5 years, SD 1.3 years) and 32 were females (mean age 10.9 years, SD 1.9 years). The children were recruited during the preparation of the initial orthodontic treatment records. Craniofacial morphology was analyzed by six angular measurements: facial axis, mandibular plane angle, inner gonial angle, lower facial height, facial depth and maxilla position. Rasterstereography was used for reconstruction of the spinal back sagittal profile. From the profile flèche cervicale, flèche lombaire and trunk inclination were determined and the correlations with the craniofacial morphology were calculated (Pearson and Mann–Whitney U test). Significant correlations were found with respect to the inner gonial angle and the flèche cervicale, the mandibular plane angle and the flèche lombaire, the inner gonial angle and the flèche lombaire, and the angular lower facial height and the flèche lombaire, as well as the inner gonial angle and the trunk inclination. The craniofacial vertical growth pattern, presented by mandibular plane angle, inner gonial angle and the angular lower facial height, and the correlation to flèche cervicale and lombaire as well as trunk inclination reveal correlations between growth pattern and sagittal back contour. PMID:19946733

  10. Coronal Spinal Balance in Adult Spine Deformity Patients With Long Spinal Fusions: A Minimum 2- to 5-Year Follow-up Study.

    PubMed

    Ploumis, Avraam; Simpson, Andrew K; Cha, Thomas D; Herzog, Joshua P; Wood, Kirkham B

    2015-11-01

    This study was a retrospective one. The objective of the study was to analyze the causes, prevalence of, and risk factors for coronal decompensation in long adult lumbar spinal instrumentation and fusion (from thoracic or upper lumbar spine) to L5 or S1. Coronal and sagittal decompensation after long fusions for spinal deformities can affect outcomes negatively. There is no study reporting the natural history of coronal spinal balance after long spinal fusions. A single-center retrospective review of data from 54 patients with spinal deformity was performed. Inclusion criteria were patients over 18 years with long fusions (>4 segments) to L5 or the pelvis who had full spine standing radiographs before surgery and up to 2-5 years postoperatively. Radiographic data included C7PL, magnitude of scoliotic curve, shoulder or pelvic asymmetry in the coronal plane, thoracic kyphosis, lumbar lordosis, and pelvic parameters (pelvic incidence, pelvic tilt, sacral slope). Coronal imbalance (CI) was considered if the C7PL was >4 cm lateral to the central sacral line, and sagittal imbalance (SI) was considered when the C7 plumbline was >4 cm anterior to the middle of the upper sacral plate. Paired t test, χ test, and repeated measures regression analysis using demographic data (age, sex, body mass index), operative (previous fusion, posterior only or anteroposterior fusion, iliac fixation or not, decompression or not, osteotomy or not) and postoperative (complications, use of bracing) data, and radiographic parameters (including SI) were performed. Patients showing CI equaled 11 (19.3%) preoperatively, remained 11 (19.3%) (4 of whom were new patients with CI) at 6 weeks postoperatively, and increased (P<0.001) to 18 (31.6%) (8 of them without initial CI) at 2-5 years follow-up. However, in terms of numeric distance of C7PL from the midsacrum, there was no statistically significant change (P>0.05) from preoperative to last follow-up. SI showed significant improvement (P<0

  11. Standardized way for imaging of the sagittal spinal balance.

    PubMed

    Morvan, Gérard; Mathieu, Philippe; Vuillemin, Valérie; Guerini, Henri; Bossard, Philippe; Zeitoun, Frédéric; Wybier, Marc

    2011-09-01

    Nowadays, conventional or digitalized teleradiography remains the most commonly used tool for the study of the sagittal balance, sometimes with secondary digitalization. The irradiation given by this technique is important and the photographic results are often poor. Some radiographic tables allow the realization of digitalized spinal radiographs by simultaneous translation of X-ray tube and receptor. EOS system is a new, very low dose system which gives good quality images, permits a simultaneous acquisition of upright frontal and sagittal views, is able to cover in the same time the spine and the lower limbs and study the axial plane on 3D envelope reconstructions. In the future, this low dose system should take a great place in the study of the pelvispinal balance. On the lateral view, several pelvic (incidence, pelvic tilt, sacral slope) and spinal (lumbar lordosis, thoracic kyphosis, Th9 sagittal offset, C7 plumb line) parameters are drawn to define the pelvispinal balance. All are interdependent. Pelvic incidence is an individual anatomic characteristic that corresponds to the "thickness" of the pelvis and governs the spinal balance. Pelvis and spine, in a harmonious whole, can be compared to an accordion, more or less compressed or stretched.

  12. Analysis of sagittal spinopelvic parameters in achondroplasia.

    PubMed

    Hong, Jae-Young; Suh, Seung-Woo; Modi, Hitesh N; Park, Jong-Woong; Park, Jung-Ho

    2011-08-15

    Prospective radiological analysis of patients with achondroplasia. To analyze sagittal spinal alignment and pelvic orientation in achondroplasia patients. Knowledge of sagittal spinopelvic parameters is important for the treatment of achondroplasia, because they differ from those of the normal population and can induce pain. The study and control groups were composed of 32 achondroplasia patients and 24 healthy volunteers, respectively. All underwent lateral radiography of the whole spine including hip joints. The radiographic parameters examined were sacral slope (SS), pelvic tilt, pelvic incidence (PI), S1 overhang, thoracic kyphosis, T10-L2 kyphosis, lumbar lordosis (LL1, LL2), and sagittal balance. Statistical analysis was performed to identify significant differences between the two groups. In addition, correlations between parameters and symptoms were sought. Sagittal spinopelvic parameters, namely, pelvic tilt, pelvic incidence, S1 overhang, thoracic kyphosis, T10-L2 kyphosis, lumbar lordosis 1 and sagittal balance were found to be significantly different in the patient and control groups (P < 0.05). In addition, sagittal parameters were found to be related to each other in the patient group (P < 0.05), that is, PI was related to SS and pelvic tilt, and LL was related to thoracic kyphosis. Furthermore, in terms of relations between spinal and pelvic parameters, LL was related to SS and PI, and sagittal balance was related to SS and PI. Furthermore, LL and T10-L2 kyphosis were found to be related to pain (P < 0.05), whereas no other parameter was found to be related to VAS scores. Sagittal parameters and possible relationships between sagittal parameters and symptoms were found to be significantly different in achondroplasia patients and normal healthy controls. The present study shows that sagittal spinal and pelvic parameters can assist the treatment of spinal disorders in achondroplasia patients.

  13. Constraints on Nonuniform Expansion in Coronal Loops

    NASA Astrophysics Data System (ADS)

    Kucera, Therese A.; DeForest, Craig; Klimchuk, James A.; Young, Peter R.

    2017-08-01

    We use measurements of coronal loop properties to constrain the hypothesis that coronal loops expand differently in different directions. A long standing problem in understanding coronal loops is that although the magnetic field is expected to expand with altitude and does indeed seem to do so on scales of active regions, individual loops seem to have fairly uniform diameters along the length of the loop. Malanushenko & Schrijver (2013) have suggested that loops may be expanding, but with a non-circular cross section. In this scenario a loop might have a constant width in the plane of the sky, but expand along the line of sight. Furthermore, such loops might be easier to see from the point of view that does not show expansion. We use Hinode/EIS and SDO/AIA data to measure loop intensities, electron densities, temperatures and dimensions in order to determine the extent to which loops may be expanding along the line of sight.

  14. The correlation between coronal balance and neuroaxial abnormalities detected on MRI in adolescent idiopathic scoliosis.

    PubMed

    Lee, Robert S; Reed, Daniel W; Saifuddin, Asif

    2012-06-01

    The indications for magnetic resonance imaging in presumed adolescent idiopathic scoliosis (AIS) have not been established, with some studies suggesting that rates of spinal cord abnormalities are low and question the use of the routine MRI in AIS. Given the restraints on MRI resources the authors performed a retrospective audit to see if the presence of coronal or sagittal misbalance-balance could be used as a surrogate marker for the presence of spinal cord abnormalities in this patient group and hence reduce the need for unnecessary MRI scans. We performed a retrospective review of imaging of patients with AIS at our centre over a 2-year-period. All MRI scans were reported by the senior author and the presence of spinal cord abnormalities noted. All plain films were assessed by a senior SpR and ST2 orthopaedic surgeons for Cobb angle, coronal balance, sagittal balance and Lenke classification. A total of 171 patients were identified with AIS. Of these, a total of 15 patients (9%) were found to have neural axis anomalies on MRI including syringomyelia, Chiari malformations and dural ectasia. The average Cobb angle was 44.9° with coronal balance varying from 67.2 mm left to 40.2 mm right. Sagittal balance varied from 125 mm negative to 83 mm positive. No correlation was found between coronal/sagittal misbalance and the presence of neural axis anomalies. Our audit demonstrates that neither coronal nor sagittal misbalance should be used as an indicator of neural axis abnormalities.

  15. Different ways to balance the spine: subtle changes in sagittal spinal curves affect regional muscle activity.

    PubMed

    Claus, Andrew P; Hides, Julie A; Moseley, G Lorimer; Hodges, Paul W

    2009-03-15

    Exploratory study of regional muscle activity in different postures. To detail the relationship between spinal curves and regional muscle activity. Sagittal balanced spinal posture (C7 above S1 in the sagittal plane) is a goal for spinal surgery and conservative ergonomics. Three combinations of thoracolumbar and lumbar spinal curves can be considered sagittal balanced postures: (i) flat-at both regions, (ii) long lordosis-lordotic at both regions, and (iii) short lordosis-thoracic kyphosis and lumbar lordosis. This study compares regional muscle activity between these 3 sagittal balanced postures in sitting, as well as a slump posture. Fine-wire electromyography (EMG) electrodes were inserted into the lumbar multifidus (deep and superficial), iliocostalis (lateral and medial), longissimus thoracis, and transversus abdominis in 14 healthy male volunteers. Fine-wire or surface EMG electrodes were also used to record activity of the obliquus internus, obliquus externus, and rectus abdominis muscles. Root mean square EMG amplitude in the flat, long lordosis, short lordosis, and slump sitting postures were normalized to maximal voluntary contraction, and also to the peak activity across the sitting postures. Muscle activity was compared between postures with a linear mixed model analysis. Of the extensor muscles, it was most notable that activity of the deep and superficial fibers of lumbar multifidus increased incrementally in the 3 sagittal balanced postures; flat, long lordosis, and short lordosis (P < 0.05). Of the abdominal muscles, obliquus internus was more active in short lordosis than the other postures (P < 0.05). Comparing the sagittal balanced postures, the flat posture showed the least muscle activity (similar to the slump posture at most muscles examined). Discrete combinations of muscle activity supported the 3 different sagittal balanced postures in sitting, providing new detail for surgeons, researchers, and therapists to distinguish between different

  16. Brain structure in sagittal craniosynostosis

    NASA Astrophysics Data System (ADS)

    Paniagua, Beatriz; Kim, Sunghyung; Moustapha, Mahmoud; Styner, Martin; Cody-Hazlett, Heather; Gimple-Smith, Rachel; Rumple, Ashley; Piven, Joseph; Gilmore, John; Skolnick, Gary; Patel, Kamlesh

    2017-03-01

    Craniosynostosis, the premature fusion of one or more cranial sutures, leads to grossly abnormal head shapes and pressure elevations within the brain caused by these deformities. To date, accepted treatments for craniosynostosis involve improving surgical skull shape aesthetics. However, the relationship between improved head shape and brain structure after surgery has not been yet established. Typically, clinical standard care involves the collection of diagnostic medical computed tomography (CT) imaging to evaluate the fused sutures and plan the surgical treatment. CT is known to provide very good reconstructions of the hard tissues in the skull but it fails to acquire good soft brain tissue contrast. This study intends to use magnetic resonance imaging to evaluate brain structure in a small dataset of sagittal craniosynostosis patients and thus quantify the effects of surgical intervention in overall brain structure. Very importantly, these effects are to be contrasted with normative shape, volume and brain structure databases. The work presented here wants to address gaps in clinical knowledge in craniosynostosis focusing on understanding the changes in brain volume and shape secondary to surgery, and compare those with normally developing children. This initial pilot study has the potential to add significant quality to the surgical care of a vulnerable patient population in whom we currently have limited understanding of brain developmental outcomes.

  17. Coronal transverse magnetohydrodynamic waves in a solar prominence.

    PubMed

    Okamoto, T J; Tsuneta, S; Berger, T E; Ichimoto, K; Katsukawa, Y; Lites, B W; Nagata, S; Shibata, K; Shimizu, T; Shine, R A; Suematsu, Y; Tarbell, T D; Title, A M

    2007-12-07

    Solar prominences are cool 10(4) kelvin plasma clouds supported in the surrounding 10(6) kelvin coronal plasma by as-yet-undetermined mechanisms. Observations from Hinode show fine-scale threadlike structures oscillating in the plane of the sky with periods of several minutes. We suggest that these represent Alfvén waves propagating on coronal magnetic field lines and that these may play a role in heating the corona.

  18. Sagittal osteotomy of the patella after Morscher

    PubMed Central

    Pećina, Marko; Hudetz, Damir; Smoljanović, Tomislav; Janković, Saša

    2009-01-01

    The aim of this study was to present long-term results of sagittal osteotomy of the patella after Morscher. The study included 70 patients treated for patellar dysplasia with a postoperative follow-up from nine to 20 years. There were 59 females and 11 males with an average age of 21 years at the time of operation. Results were evaluated for the entire group of 70 patients and then presented separately for the 30 patients in whom sagittal osteotomy of the patella was performed as a single procedure and 40 patients in whom, in addition to sagittal osteotomy of the patella, medialisation and ventralisation or distalisation of the tibial tuberosity were also performed. The mean value of the Wiberg patellar angle was 112 degrees preoperatively and 140 degrees postoperatively. In the whole group of patients excellent results were obtained in 24 (35%), good results in 30 (42%), fair results in 13 (19%) and poor results in three (4%) patients. In 30 patients with sagittal osteotomy as a single operation excellent results were obtained in 13 (43%), good results in 14 (47%) and fair results in three (10%) patients, while in the 40 patients with sagittal osteotomy and additional surgical procedures, 11 (27%) were excellent, 16 (40%) good, ten (25%) fair and three (8%) had poor results. Sagittal osteotomy of the patella after Morscher is an enrichment of the spectrum of the secondary-causal and preventive procedures for the treatment of patello-femoral disorders. PMID:19998034

  19. Sagittal balance correction of idiopathic scoliosis using the in situ contouring technique.

    PubMed

    Charles, Yann Philippe; Bouchaïb, Julia; Walter, Axel; Schuller, Sébastien; Sauleau, Erik André; Steib, Jean-Paul

    2012-10-01

    Idiopathic scoliosis can lead to sagittal imbalance. The relationship between thoracic hyper- and hypo-kyphotic segments, vertebral rotation and coronal curve was determined. The effect of segmental sagittal correction by in situ contouring was analyzed. Pre- and post-operative radiographs of 54 scoliosis patients (Lenke 1 and 3) were analyzed at 8 years follow-up. Cobb angles and vertebral rotation were determined. Sagittal measurements were: kyphosis T4-T12, T4-T8 and T9-T12, lordosis L1-S1, T12-L2 and L3-S1, pelvic incidence, pelvic tilt, sacral slope, T1 and T9 tilt. Thoracic and lumbar curves were significantly reduced (p = 0.0001). Spino-pelvic parameters, T1 and T9 tilt were not modified. The global T4-T12 kyphosis decreased by 2.1° on average (p = 0.066). Segmental analysis evidenced a significant decrease of T4-T8 hyperkyphosis by 6.6° (p = 0.0001) and an increase of segmental hypokyphosis T9-T12 by 5.0° (p = 0.0001). Maximal vertebral rotation was located at T7, T8 or T9 and correlated (r = 0.422) with the cranial level of the hypokyphotic zone (p = 0.003). This vertebra or its adjacent levels corresponded to the coronal apex in 79.6 % of thoracic curves. Lenke 1 and 3 curves can show normal global kyphosis, divided in cranial hyperkyphosis and caudal hypokyphosis. The cranial end of hypokyphosis corresponds to maximal rotation. These vertebrae have most migrated anteriorly and laterally. The sagittal apex between segmental hypo- and hyper-kyphosis corresponds to the coronal thoracic apex. A segmental sagittal imbalance correction is achieved by in situ contouring. The concept of segmental imbalance is useful when determining the levels on which surgical detorsion may be focused.

  20. Coronal Hole Coming Around

    NASA Image and Video Library

    2016-12-06

    A substantial coronal hole began to rotate into view over the past few days (Dec. 1-2, 2016). Coronal holes are magnetically open areas of the sun's magnetic field structure that spew streams of high speed solar wind into space. In about a week or so that coronal hole might send streams of particles in the direction of Earth. Often times these streams can interact with Earth's magnetosphere and generate aurora. The images were taken in a wavelength of extreme ultraviolet light. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA21208

  1. Returning Coronal Hole

    NASA Image and Video Library

    2017-02-06

    A substantial coronal hole rotated across the face of the sun this past week and is again streaming solar wind towards Earth (Jan. 30 - Feb. 2, 2017). This same coronal hole was facing Earth about a month ago and has rotated into a similar position again. Coronal holes are areas of open magnetic field from which solar wind particles stream into space. In this wavelength of extreme ultraviolet light it appears as a dark area near the center and lower portion of the sun. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA11177

  2. Coronal Hole Faces Earth

    NASA Image and Video Library

    2017-08-14

    A substantial coronal hole rotated into a position where it is facing Earth (Aug. 9-11, 2017). Coronal holes are areas of open magnetic field that spew out charged particles as solar wind that spreads into space. If that solar wind interacts with our own magnetosphere it can generate aurora. In this view of the sun in extreme ultraviolet light, the coronal hole appears as the dark stretch near the center of the sun. It was the most distinctive feature on the sun over the past week. Movies are available at https://photojournal.jpl.nasa.gov/catalog/PIA21874

  3. Comparing Acute Bouts of Sagittal Plane Progression Foam Rolling vs. Frontal Plane Progression Foam Rolling.

    PubMed

    Peacock, Corey A; Krein, Darren D; Antonio, Jose; Sanders, Gabriel J; Silver, Tobin A; Colas, Megan

    2015-08-01

    Many strength and conditioning professionals have included the use of foam rolling devices within a warm-up routine prior to both training and competition. Multiple studies have investigated foam rolling in regards to performance, flexibility, and rehabilitation; however, additional research is necessary in supporting the topic. Furthermore, as multiple foam rolling progressions exist, researching differences that may result from each is required. To investigate differences in foam rolling progressions, 16 athletically trained males underwent a 2-condition within-subjects protocol comparing the differences of 2 common foam rolling progressions in regards to performance testing. The 2 conditions included a foam rolling progression targeting the mediolateral axis of the body (FRml) and foam rolling progression targeting the anteroposterior axis (FRap). Each was administered in adjunct with a full-body dynamic warm-up. After each rolling progression, subjects performed National Football League combine drills, flexibility, and subjective scaling measures. The data demonstrated that FRml was effective at improving flexibility (p ≤ 0.05) when compared with FRap. No other differences existed between progressions.

  4. SPINNING MOTIONS IN CORONAL CAVITIES

    SciTech Connect

    Wang, Y.-M.; Stenborg, G. E-mail: guillermo.stenborg.ctr.ar@nrl.navy.mi

    2010-08-20

    In movies made from Fe XII 19.5 nm images, coronal cavities that graze or are detached from the solar limb appear as continually spinning structures, with sky-plane projected flow speeds in the range 5-10 km s{sup -1}. These whirling motions often persist in the same sense for up to several days and provide strong evidence that the cavities and the immediately surrounding streamer material have the form of helical flux ropes viewed along their axes. A pronounced bias toward spin in the equatorward direction is observed during 2008. We attribute this bias to the poleward concentration of the photospheric magnetic flux near sunspot minimum, which leads to asymmetric heating along large-scale coronal loops and tends to drive a flow from higher to lower latitudes; this flow is converted into an equatorward spinning motion when the loops pinch off to form a flux rope. As sunspot activity increases and the polar fields weaken, we expect the preferred direction of the spin to reverse.

  5. Two Coronal Holes

    NASA Image and Video Library

    2015-04-03

    A pair of substantial coronal holes were the most notable features on the Sun over the week of Mar. 28 - Apr. 2, 2015. The images were taken in a wavelength of extreme ultraviolet light by NASA GSFC Solar Dynamics Observatory.

  6. Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Crooker, Nancy; Joselyn, Jo Ann; Feynman, Joan

    The early 1970's can be said to mark the beginning of The Enlightenment in the history of the Space Age, literally as well as by analogy to European history. Instruments blinded by Earth's atmosphere were lifted above and, for the first time, saw clearly and continuously the ethereal white light and sparkling x-rays from the solar corona. From these two bands of the light spectrum came images of coronal mass ejections and coronal holes, respectively. But whereas coronal holes were immediately identified as the source of high-speed solar wind streams, at first coronal mass ejections were greeted only by a sense of wonder. It took years of research to identify their signatures in the solar wind before the fastest ones could be identified with the well-known shock disturbances that cause the most violent space storms.

  7. Radiographic analysis of the sagittal alignment and balance of the spine in asymptomatic subjects.

    PubMed

    Vialle, Raphaël; Levassor, Nicolas; Rillardon, Ludovic; Templier, Alexandre; Skalli, Wafa; Guigui, Pierre

    2005-02-01

    There is an increasing recognition of the clinical importance of the sagittal plane alignment of the spine. A prospective study of several radiographic parameters of the sagittal profile of the spine was conducted to determine the physiological values of these parameters, to calculate the variations of these parameters according to epidemiological and morphological data, and to study the relationships among all of these parameters. Sagittal radiographs of the head, spine, and pelvis of 300 asymptomatic volunteers, made with the subject standing, were evaluated. The following parameters were measured: lumbar lordosis, thoracic kyphosis, T9 sagittal offset, sacral slope, pelvic incidence, pelvic tilt, intervertebral angulation, and vertebral wedging angle from T9 to S1. The radiographs were digitized, and all measurements were performed with use of a software program. Two different analyses, a descriptive analysis characterizing these parameters and a multivariate analysis, were performed in order to study the relationships among all of them. The mean values (and standard deviations) were 60 degrees 10 degrees for maximum lumbar lordosis, 41 degrees +/- 8.4 degrees for sacral slope, 13 degrees +/- 6 degrees for pelvic tilt, 55 degrees +/-10.6 degrees for pelvic incidence, and 10.3 degrees +/- 3.1 degrees for T9 sagittal offset. A strong correlation was found between the sacral slope and the pelvic incidence (r = 0.8); between maximum lumbar lordosis and sacral slope (r = 0.86); between pelvic incidence and pelvic tilt (r = 0.66); between maximum lumbar lordosis and pelvic incidence, pelvic tilt, and maximum thoracic kyphosis (r = 0.9); and, finally, between pelvic incidence and T9 sagittal offset, sacral slope, pelvic tilt, maximum lumbar lordosis, and thoracic kyphosis (r = 0.98). The T9 sagittal offset, reflecting the sagittal balance of the spine, was dependent on three separate factors: a linear combination of the pelvic incidence, maximum lumbar lordosis, and

  8. Influence of implant rod curvature on sagittal correction of scoliosis deformity.

    PubMed

    Salmingo, Remel Alingalan; Tadano, Shigeru; Abe, Yuichiro; Ito, Manabu

    2014-08-01

    Deformation of in vivo-implanted rods could alter the scoliosis sagittal correction. To our knowledge, no previous authors have investigated the influence of implanted-rod deformation on the sagittal deformity correction during scoliosis surgery. To analyze the changes of the implant rod's angle of curvature during surgery and establish its influence on sagittal correction of scoliosis deformity. A retrospective analysis of the preoperative and postoperative implant rod geometry and angle of curvature was conducted. Twenty adolescent idiopathic scoliosis patients underwent surgery. Average age at the time of operation was 14 years. The preoperative and postoperative implant rod angle of curvature expressed in degrees was obtained for each patient. Two implant rods were attached to the concave and convex side of the spinal deformity. The preoperative implant rod geometry was measured before surgical implantation. The postoperative implant rod geometry after surgery was measured by computed tomography. The implant rod angle of curvature at the sagittal plane was obtained from the implant rod geometry. The angle of curvature between the implant rod extreme ends was measured before implantation and after surgery. The sagittal curvature between the corresponding spinal levels of healthy adolescents obtained by previous studies was compared with the implant rod angle of curvature to evaluate the sagittal curve correction. The difference between the postoperative implant rod angle of curvature and normal spine sagittal curvature of the corresponding instrumented level was used to evaluate over or under correction of the sagittal deformity. The implant rods at the concave side of deformity of all patients were significantly deformed after surgery. The average degree of rod deformation Δθ at the concave and convex sides was 15.8° and 1.6°, respectively. The average preoperative and postoperative implant rod angle of curvature at the concave side was 33.6° and 17.8

  9. Surgical anatomy of the penis in hypospadias: magnetic resonance imaging study of the tissue planes, vessels, and collaterals.

    PubMed

    Kureel, Shiv Narain; Gupta, Archika; Sunil, Kanoujia; Dheer, Yadvendra; Kumar, Manoj; Tomar, Vinod Kumar

    2015-05-01

    To report the surgical anatomy of the penis in hypospadias with study of vessels in relation to fascial planes, glans, corpora cavernosa, and corpus spongiosum using magnetic resonance imaging. Twelve hypospadias presenting at older age (8-20 years) were studied with 1.5-T magnetic resonance imaging scanner and a 3-inch surface coil. Precontrast and postcontrast images were acquired using fast-spin echo sequences in sagittal, coronal, and transverse planes. The findings were processed in Volume Share 4.5, version Workstation, of General Electric Healthcare. Anatomic findings were verified during surgery. With imaging and surgical findings, a 3-dimensional conceptual diagram of surgical anatomy was created. Distinct layers of the skin, dartos fascia, Buck fascia, tunica albuginea, glans urothelium, lamina propria of glans, and corpus spongiosum were delineated with their spatial relationship. Axial pattern vessels of the dartos and its anastomosis with branches of dorsal penile vessels at the coronal sulcus, perforators along the corpus spongiosum, subglanular extension of the fascia, and intraglanular branches of the dorsal penile artery forming an arcade were visualized. Dorsomedial and dorsolateral axial pattern vessels are present in penile dartos with relative avascularity at dorsal midline in most cases. Subglanular extension of Buck fascia fused with the basal lamina propria of glans forms a barrier between the tip of corpora and the intraglanular arcade of vessels. Collaterals are present at coronal sulcus, along the bifurcated corpus spongiosum, and the dartos enabling blood flow between the terminal most branches of the external and internal pudendal vessels. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Assessment of Coronal Radiographic Parameters of the Spine in the Treatment of Adolescent Idiopathic Scoliosis

    PubMed Central

    Karami, Mohsen; Maleki, Arash; Mazda, Keyvan

    2016-01-01

    Background: To determine the most important preoperative factors that affect postoperative coronal parameters of scoliotic curves. Methods: All Adolescent Idiopathic Scoliosis (AIS) patients included in the study were classified according to Lenke and King Classification. The fusion levels were selected according to the rigidity of the existing curves (correction less than 50%), tilt of T1 and shoulders, sagittal angle of the curves and with considering stable and neutral end vertebra. The radiographic coronal parameters: shoulders tilt angle, iliolumbar angle and coronal balance were measured in all patients before, after, and in the last follow-up visit. Results: One hundred twenty patients after mean of 25 months follow-up (18-40 months) were included in the study. Before operation, abnormal coronal balance (more than 2 cm shift) was noticed in 46 patents (38%) and in the last visit, was noted in 22 patients (18%). Multivariate regression analysis revealed a significant predictive value of the preoperative coronal balance on the last visit coronal balance (P value=0.01). Conclusion: Preoperative coronal balance is very important to make a balanced spine after surgery. Other parameters like Lenke classification or main thoracic overcorrection did not affect postoperative coronal decompensation. PMID:27847853

  11. Walking in simulated Martian gravity: Influence of added weight on sagittal dynamic stability

    NASA Astrophysics Data System (ADS)

    Scott-Pandorf, Melissa M.; O'Connor, Daniel P.; Layne, Charles S.; Josić, Krešimir; Kurz, Max J.

    2010-05-01

    With human exploration of the Moon and Mars on the horizon, research considerations for space suit redesign have surfaced. Review of Apollo mission videos revealed repeated instance of falling during extravehicular activities. A better understanding of how suit weight influences the sagittal dynamic stability of the gait pattern may provide insight for new suit design such that space missions may have more productive extravehicular activities and smaller risk of falls that may cause injuries and damage equipment. Participants walked for 4 min in simulated Martian gravity with additional loads of 0%, 15%, 30% and 45% of their body weight. Floquet and Lyapunov analysis techniques were used to quantify the dynamic stability of the sagittal plane gait pattern. Additionally, sagittal plane joint kinematics were evaluated to determine if any modification occurred. Results indicated that weight (i.e., added load) had little effect on the sagittal dynamic stability or joint kinematics while in simulated Martian gravity. Potentially, suit weight may not be a priority for space suit redesign.

  12. Assessment of normal ACL double bundle anatomy in standard viewing planes by magnetic resonance imaging.

    PubMed

    Starman, James S; Vanbeek, Corinne; Armfield, Derek R; Sahasrabudhe, Amit; Baker, Champ L; Irrgang, James J; Fu, Freddie H

    2007-05-01

    Anatomical studies show that the native ACL consists of two distinct functional bundles, termed the anteromedial (AM) and posterolateral (PL) bundles. The utility of using routine magnetic resonance imaging (MRI) to distinguish the individual bundles of the ACL has not been evaluated. The purpose of this study was to evaluate the intra- and inter-observer agreement for assessment of the AM and PL bundles using MRI in the axial, coronal, and sagittal viewing planes. We identified a series of patients seen in the senior author's clinic during a 16-month period. Images were independently evaluated in blinded fashion at two separate time points by a musculoskeletal radiologist and two orthopaedic residents. The AM bundle was detected in most planes of view with high frequency and reliability, while detection of the PL bundle was less frequent and had a lower associated reliability. Our results indicate that it is difficult to reliably detect both the AM and PL bundles using a low-field strength magnet with standard planes of view. It has been demonstrated that the ACL may be imaged effectively in planes that are based on the natural course of the ligament, and it is likely that this will also facilitate visualization of the individual AM and PL bundles. The use of additional oblique planes of view offers a potential approach for improved evaluation of the ACL, even with low field strength magnets. Future work in this area may assist in the pre-operative assessment of isolated AM or PL bundle injuries, facilitating a more anatomic approach to ACL reconstruction.

  13. Stellar Coronal Astronomy

    NASA Astrophysics Data System (ADS)

    Favata, Fabio; Micela, Giuseppina

    2003-10-01

    Coronal astronomy is by now a fairly mature discipline, with a quarter century having gone by since the detection of the first stellar X-ray coronal source (Capella), and having benefitted from a series of major orbiting observing facilities. Serveral observational characteristics of coronal X-ray and EUV emission have been solidly established through extensive observations, and are by now common, almost text-book, knowledge. At the same time the implications of coronal astronomy for broader astrophysical questions (e.g.Galactic structure, stellar formation, stellar structure, etc.) have become appreciated. The interpretation of stellar coronal properties is however still often open to debate, and will need qualitatively new observational data to book further progress. In the present review we try to recapitulate our view on the status of the field at the beginning of a new era, in which the high sensitivity and the high spectral resolution provided by Chandra and SMM-Newton will address new questions which were not accessible before.

  14. Sagittal laser optical tomography for imaging of rheumatoid finger joints.

    PubMed

    Hielscher, Andreas H; Klose, Alexander D; Scheel, Alexander K; Moa-Anderson, Bryte; Backhaus, Marina; Netz, Uwe; Beuthan, Jürgen

    2004-04-07

    We present a novel optical tomographic imaging system that was designed to determine two-dimensional spatial distribution of optical properties in a sagittal plane through finger joints. The system incorporates a single laser diode and a single silicon photodetector into a scanning device that records spatially resolved light intensities as they are transmitted through a finger. These data are input to a model-based iterative image reconstruction (MOBIIR) scheme, which uses the equation of radiative transfer (ERT) as a forward model for light propagation through tissue. We have used this system to obtain tomographic images of six proximal interphalangeal finger joints from two patients with rheumatoid arthritis. The optical images were compared to clinical symptoms and ultrasound images.

  15. Lumbar Lordosis Minus Thoracic Kyphosis: A Novel Regional Predictor for Sagittal Balance in Elderly Populations.

    PubMed

    Yang, Changwei; Yang, Mingyuan; Wei, Xianzhao; Shao, Jie; Chen, Yuanyuan; Zhao, Jian; Zhu, Xiaodong; He, Dawei; Li, Ming

    2016-03-01

    A retrospective study. The aim of this study is to introduce a novel regional predictor for sagittal balance in elderly populations and explore its effectiveness of evaluating sagittal balance. Sagittal balance is getting increasing recognition of importance due to its significant association of health-related quality of life. However, no regional parameters could well reflect and predict the whole sagittal balance. Medical records of elderly patients in our outpatient clinic from January 2012 to January 2014 were reviewed with standing full-spine lateral radiograph. Radiological parameters were evaluated, including max thoracic kyphosis (maxTK), max lumbar lordosis (maxLL), LL minus TK(LL-TK), PI minus LL (PI-LL), sacrum slope (SS), pelvic tilt (PT), pelvic incidence (PI), and SVA (sagittal vertical axis). Correlation analysis between SVA, LL-TK, and other radiological spinopelvic parameters and was pursued. Patients were divided into two groups according to whether patients were well-aligned in sagittal plane: Group A (well-aligned, SVA ≤50  mm) and Group B (poorly aligned, SVA >50  mm), and demographic and sagittal parameters were compared. LL-TK ≥0° and PI-LL ≤13° were used as a threshold value to evaluate their effectiveness of prediction for sagittal balance. A total of 129 patients (M: 25 and F: 104) were included in this study. SVA was significantly correlated with NRS (numeric rating scales), age, maxLL, PT, LL-TK, and PI-LL (all, P < 0.05). Age, maxTK, maxLL, SS, PT, PI, SVA, and NRS were significantly correlated with LL-TK (all P < 0.05). Significant differences were found in age, maxLL, PT, LL-TK, PI-LL, SVA, and NRS between Group A (M: 15 and F: 72) and Group B (M: 10 and F: 32) (all P < 0.05). Furthermore, both LL-TK ≥0° and PI-LL ≤13° were observed in 75 patents, among which SVA ≤50 mm was found in 67 patients (89%). Among patients whose LL-TK and PI-LL were <0° and >13°, 34 patients were poorly aligned (34/39, 87

  16. White-Light Polarization and Large-Scale Coronal Structures

    NASA Astrophysics Data System (ADS)

    Badalyan, O. G.; Livshits, M. A.; Sýkora, J.

    1997-06-01

    The results of the white-light polarization measurements performed during three solar eclipses (1973, 1980, 1991) are presented. The eclipse images were processed and analysed by the same technique and method and, consequently, the distributions of the polarization and coronal intensity around the Sun were obtained in unified form for all three solar eclipses. The mutual comparisons of our results, and their comparison with the distributions found by other authors, allowed the real accuracy of the current measurements of the white-light corona polarization, which is not worse than +/-5%, to be estimated. We have investigated the behaviour of the polarization in dependence on heliocentric distance in helmet streamers and coronal holes. Simultaneous interpretation of the data on polarization and intensity in white-light helmet streamers is only possible if a considerable concentration of coronal matter (plasma) towards the plane of the sky is assumed. The values obtained for the coronal hole regions can be understood within the framework of a spherically symmetrical model of the low density solar atmosphere. A tendency towards increasing polarization in coronal holes, connected with the decrease of the hole's size and with the transition from the minimum to the maximum of the solar cycle, was noticed. The problem of how the peculiarities of the large-scale coronal structures are related to the orientation of the global (dipole) solar magnetic field and to the degree of the goffer character of the coronal and interplanetary current sheet is discussed briefly.

  17. Asymmetric osteotomy of the spine for coronal imbalance: a technical report.

    PubMed

    Thambiraj, Sathya; Boszczyk, Bronek M

    2012-05-01

    Technical report on the surgical technique of asymmetric osteotomy of the spine for coronal imbalance. To describe a successful method of performing asymmetrical pedicle subtraction osteotomy (APSO) through a posterior only approach. Rigid coronal deformity of the spine can be sharply angulated and can create significant coronal imbalance. Surgical correction is the only definitive treatment of restoring the balance as bracing is unhelpful. Corrective surgery can be anterior or posterior. The literature on the methods of surgical correction of rigid coronal deformities of the spine is limited. Unlike osteotomies for sagittal imbalance, blunt dissection of the anterior cortex is necessary in asymmetrical osteotomy to allow resection of the anterior cortex for closure of the wedge. We describe a method by which we performed this in the thoracic and lumbar spine with case examples. After insertion of pedicle screws, laminectomy and unilateral facetectomy of the proposed level of osteotomy is performed. Next, dissection lateral to the pedicle and vertebral body is performed bluntly with mastoids to reach the front of the anterior cortex and confirmed with fluoroscopy. An oblique osteotomy including the lateral and posterior cortex is performed above and below the pedicle under imaging. The osteotomy site is closed through unilateral compression. Satisfactory correction of coronal deformity can be achieved with APSO from an isolated posterior approach. In contrast to sagittal osteotomies, blunt dissection along the anterior cortex is necessary to allow safe resection of anterior cortical bone for closure of the wedge.

  18. SOLAR WIND AND CORONAL BRIGHT POINTS INSIDE CORONAL HOLES

    SciTech Connect

    Karachik, Nina V.; Pevtsov, Alexei A. E-mail: apevtsov@nso.edu

    2011-07-01

    Observations of 108 coronal holes (CHs) from 1998-2008 were used to investigate the correlation between fast solar wind (SW) and several parameters of CHs. Our main goal was to establish the association between coronal bright points (CBPs; as sites of magnetic reconnection) and fast SW. Using in situ measurements of the SW, we have connected streams of the fast SW at 1 AU with their source regions, CHs. We studied a correlation between the SW speed and selected parameters of CHs: total area of the CH, total intensity inside the CH, fraction of area of the CH associated with CBPs, and their integrated brightness inside each CH. In agreement with previous studies, we found that the SW speed most strongly correlates with the total area of the CHs. The correlation is stronger for the non (de)projected areas of CHs (which are measured in image plane) suggesting that the near-equatorial parts of CHs make a larger contribution to the SW measured at near Earth orbit. This correlation varies with solar activity. It peaks for periods of moderate activity, but decreases slightly for higher or lower levels of activity. A weaker correlation between the SW speed and other studied parameters was found, but it can be explained by correlating these parameters with the CH's area. We also studied the spatial distribution of CBPs inside 10 CHs. We found that the density of CBPs is higher in the inner part of CHs. As such, results suggest that although the reconnection processes occurring in CBPs may contribute to the fast SW, they do not serve as the main mechanism of wind acceleration.

  19. Solar Wind and Coronal Bright Points inside Coronal Holes

    NASA Astrophysics Data System (ADS)

    Karachik, Nina V.; Pevtsov, Alexei A.

    2011-07-01

    Observations of 108 coronal holes (CHs) from 1998-2008 were used to investigate the correlation between fast solar wind (SW) and several parameters of CHs. Our main goal was to establish the association between coronal bright points (CBPs; as sites of magnetic reconnection) and fast SW. Using in situ measurements of the SW, we have connected streams of the fast SW at 1 AU with their source regions, CHs. We studied a correlation between the SW speed and selected parameters of CHs: total area of the CH, total intensity inside the CH, fraction of area of the CH associated with CBPs, and their integrated brightness inside each CH. In agreement with previous studies, we found that the SW speed most strongly correlates with the total area of the CHs. The correlation is stronger for the non (de)projected areas of CHs (which are measured in image plane) suggesting that the near-equatorial parts of CHs make a larger contribution to the SW measured at near Earth orbit. This correlation varies with solar activity. It peaks for periods of moderate activity, but decreases slightly for higher or lower levels of activity. A weaker correlation between the SW speed and other studied parameters was found, but it can be explained by correlating these parameters with the CH's area. We also studied the spatial distribution of CBPs inside 10 CHs. We found that the density of CBPs is higher in the inner part of CHs. As such, results suggest that although the reconnection processes occurring in CBPs may contribute to the fast SW, they do not serve as the main mechanism of wind acceleration.

  20. Substantial Coronal Holes

    NASA Image and Video Library

    2016-10-21

    A pair of large coronal holes rotated into view over the past few days (Oct. 20-21, 2016). Coronal holes appear dark in certain wavelengths of extreme ultraviolet light, such as in the wavelength used here. These holes are areas of open magnetic field that spew solar wind into space. Sometimes, when they are facing Earth, they can cause geomagnetic disturbances that generate aurora. The lines you see were drawn to represent how solar scientists are modeling the magnetic field lines. Movies are available at the Photojournal http://photojournal.jpl.nasa.gov/catalog/PIA15378

  1. Lengthy Coronal Hole

    NASA Image and Video Library

    2017-01-09

    An elongated coronal hole rotated across the face of the sun this past week so that it is now streaming solar wind towards Earth (Jan. 2-5, 2017). Coronal holes are areas of open magnetic field from which solar wind particles stream into space. In this wavelength of extreme ultraviolet light it appears as a dark area near the center and lower portion of the sun. The particle stream will likely generate aurora here on Earth. Check spaceweather.com for updates on auroral activity. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA14093

  2. Extensive Coronal Hole

    NASA Image and Video Library

    2017-09-02

    A large coronal hole has been spewing solar wind particles in the general direction of Earth over the past few days (Aug. 31- Sept. 1, 2017). It is the extensive dark area that stretches from the top of the sun and angles down to the right. Coronal holes are areas of open magnetic field, which allow charge particles to escape into space. They appear dark in certain wavelengths of extreme ultraviolet light such as shown here. These clouds of particles can cause aurora to appear, particularly in higher latitude regions. Movies are available at https://photojournal.jpl.nasa.gov/catalog/PIA21942

  3. Coronal Hole Front and Center

    NASA Image and Video Library

    2016-05-18

    A substantial coronal hole had rotated so that it temporarily faced right towards Earth May, 17-19, 2016. This coronal hole area is the dark area at the top center of this image from NASA Solar Dynamics Observatory.

  4. Geometrical Properties of Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Cremades, Hebe; Bothmer, Volker

    Based on the SOHO/LASCO dataset, a collection of "structured" coronal mass ejections (CMEs) has been compiled within the period 1996-2002, in order to analyze their three-dimensional configuration. These CME events exhibit white-light fine structures, likely indicative of their possible 3D topology. From a detailed investigation of the associated low coronal and photospheric source regions, a generic scheme has been deduced, which considers the white-light topology of a CME projected in the plane of the sky as being primarily dependent on the orientation and position of the source region's neutral line on the solar disk. The obtained results imply that structured CMEs are essentially organized along a symmetry axis, in a cylindrical manner. The measured dimensions of the cylinder's base and length yield a ratio of 1.6. These CMEs seem to be better approximated by elliptic cones, rather than by the classical ice cream cone, characterized by a circular cross section.

  5. No Differences Identified in Transverse Plane Biomechanics Between Medial Pivot and Rotating Platform Total Knee Implant Designs.

    PubMed

    Papagiannis, Georgios I; Roumpelakis, Ilias M; Triantafyllou, Athanasios I; Makris, Ioannis N; Babis, George C

    2016-08-01

    Total knee arthroplasties (TKAs) using well-designed, fixed bearing prostheses, such as medial pivot (MP), have produced good long-term results. Rotating-platform, posterior-stabilized (RP-PS) mobile bearing implants were designed to decrease polyethylene wear. Sagittal and coronal plane TKA biomechanics are well examined and correlated to polyethylene wear. However, limited research findings describe this relationship in transverse plane. We assumed that although axial plane biomechanics might not be the most destructive parameters on polyethylene wear, it is important to clarify their role because both joint kinematics and kinetics in all 3 planes are important input parameters for TKA wear testing (International Organization for Standardization 14243-1 and 14343-3). Our hypothesis was that transverse plane overall range of motion (ROM) and/or peak moment show differences that reflect on wear advantages when compared RP-PS implants to MP designs. Two groups (MPs = 24 and RP-PSs = 22 subjects) were examined by using 3D gait analysis. The variables were total internal-external rotation (IER) ROM and peak IER moments. No statistically significant difference was demonstrated between the 2 groups in kinetics (P = .389) or kinematics (P = .275). In the present study, no wear advantages were found between 2 TKAs. Both designs showed identical kinetics at the transverse plane in level-ground walking. Kinematic analysis could not illustrate any statistically significant difference in terms of overall IER ROM. Nevertheless, kinematic gait pattern differences observed possibly reflect different patterns of joint surface motion or abnormal gait patterns. Thus, wear testing with various input waveforms combined with functional data analysis will be necessary to identify the actual effects of gait variability on polyethylene wear. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Global Coronal Waves

    NASA Astrophysics Data System (ADS)

    Chen, P. F.

    2016-02-01

    After the Solar and Heliospheric Observatory (SOHO) was launched in 1996, the aboard Extreme Ultraviolet Imaging Telescope (EIT) observed a global coronal wave phenomenon, which was initially named ``EIT wave" after the telescope. The bright fronts are immediately followed by expanding dimmings. It has been shown that the brightenings and dimmings are mainly due to plasma density increase and depletion, respectively. Such a spectacular phenomenon sparked long-lasting interest and debates. The debates were concentrated on two topics, one is about the driving source, and the other is about the nature of this wavelike phenomenon. The controversies are most probably because there may exist two types of large-scale coronal waves that were not well resolved before the Solar Dynamics Observatory (SDO) was launched: one is a piston-driven shock wave straddling over the erupting coronal mass ejection (CME), and the other is an apparently propagating front, which may correspond to the CME frontal loop. Such a two-wave paradigm was proposed more than 13 years ago, and now is being recognized by more and more colleagues. In this paper, we review how various controversies can be resolved in the two-wave framework and how important it is to have two different names for the two types of coronal waves.

  7. Tangential and sagittal curvature from the normals computed by the null screen method in corneal topography

    NASA Astrophysics Data System (ADS)

    Estrada-Molina, Amilcar; Díaz-Uribe, Rufino

    2011-08-01

    A new method for computing the tangential and sagittal curvatures from the normals to a cornea is proposed. The normals are obtained through a Null Screen method from the coordinates of the drops shaped spots at the null screen, the coordinates on a reference approximating surface and the centroids on the image plane. This method assumes that the cornea has rotational symmetry and our derivations will be carried out in the meridional plane that contains the symmetry axis. Experimental results are shown for a calibration spherical surface, using cylindrical null screens with radial point arrays.

  8. Coronal mass ejections and coronal structures

    NASA Technical Reports Server (NTRS)

    Hildner, E.; Bassi, J.; Bougeret, J. L.; Duncan, R. A.; Gary, D. E.; Gergely, T. E.; Harrison, R. A.; Howard, R. A.; Illing, R. M. E.; Jackson, B. V.

    1986-01-01

    Research on coronal mass ejections (CMF) took a variety of forms, both observational and theoretical. On the observational side there were: case studies of individual events, in which it was attempted to provide the most complete descriptions possible, using correlative observations in diverse wavelengths; statistical studies of the properties CMEs and their associated activity; observations which may tell us about the initiation of mass ejections; interplanetary observations of associated shocks and energetic particles even observations of CMEs traversing interplanetary space; and the beautiful synoptic charts which show to what degree mass ejections affect the background corona and how rapidly (if at all) the corona recovers its pre-disturbance form. These efforts are described in capsule form with an emphasis on presenting pictures, graphs, and tables so that the reader can form a personal appreciation of the work and its results.

  9. Coronal Magnetometry in the Future

    NASA Astrophysics Data System (ADS)

    Li, Hui; Tomczyk, Steven

    Coronal magnetic field plays a crucial role in solar activity. However, due to the high temperature, low density and weak magnetic field properties of the corona, it is hard to directly measure coronal magnetic field, especially for the vector magnetic field. In this presentation, I will briefly review the past endeavor to measure the coronal magnetic field and present current methodology. I will introduce in more detail about the proposed Coronal Magnetism Telescopes of China (COMTEC) and the Coronal Solar Magnetism Observatory (COSMO) in the United States of America. Both of them are dedicated to measure the vector magnetic field in the corona as well as chromospheric magnetic field. They, once established, will certainly contribute much to the comprehensive understanding of important questions in solar physics, such as coronal and chromospheric heating, solar wind acceleration, global and long-time variation of coronal magnetic field, etc.

  10. Ellis-van Creveld Syndrome with Sagittal Craniosynostosis.

    PubMed

    Fischer, Andrew S; Weathers, William M; Wolfswinkel, Erik M; Bollo, Robert J; Hollier, Larry H; Buchanan, Edward P

    2015-06-01

    Ellis-van Creveld syndrome (EVC) is a rare disorder (the incidence is estimated at around 7/1,000,000) characterized by the clinical tetrad of chondrodystrophy, polydactyly, ectodermal dysplasia, and cardiac anomalies. Sagittal synostosis is characterized by a dolichocephalic head shape resulting from premature fusion of the sagittal suture. Both are rare disorders, which have never been reported together. We present a case of EVC and sagittal synostosis. We report the clinical features of a Hispanic boy with EVC and sagittal craniosynostosis who underwent cranial vault remodeling. The presentation of this patient is gone over in detail. A never before reported case of EVC and sagittal synostosis is presented in detail.

  11. SNAPing Coronal Iron

    NASA Astrophysics Data System (ADS)

    Ayres, Thomas

    2009-07-01

    This is a Snapshot Survey to explore two forbidden lines of highly ionized iron in late-type coronal sources. Fe XII 1349 {T 2 MK} and Fe XXI 1354 {T 10 MK} - well known to Solar Physics - have been detected in about a dozen cool stars, mainly with HST/STIS. The UV coronal forbidden lines are important because they can be observed with velocity resolution of better than 15 km/s, whereas even the state-of-the-art X-ray spectrometers on Chandra can manage only 300 km/s in the kilovolt band where lines of highly ionized iron more commonly are found. The kinematic properties of hot coronal plasmas, which are of great interest to theorists and modelers, thus only are accessible in the UV at present. The bad news is that the UV coronal forbidden lines are faint, and were captured only in very deep observations with STIS. The good news is that 3rd-generation Cosmic Origins Spectrograph, slated for installation in HST by SM4, in a mere 25 minute exposure with its G130M mode can duplicate the sensitivity of a landmark 25-orbit STIS E140M observation of AD Leo, easily the deepest such exposure of a late-type star so far. Our goal is to build up understanding of the properties of Fe XII and Fe XXI in additional objects beyond the current limited sample: how the lineshapes depend on activity, whether large scale velocity shifts can be detected, and whether the dynamical content of the lines can be inverted to map the spatial morphology of the stellar corona {as in "Doppler Imaging''}. In other words, we want to bring to bear in the coronal venue all the powerful tricks of spectroscopic remote sensing, well in advance of the time that this will be possible exploiting the corona's native X-ray radiation. The 1290-1430 band captured by side A of G130M also contains a wide range of key plasma diagnostics that form at temperatures from below 10,000 K {neutral lines of CNO}, to above 200,000 K {semi-permitted O V 1371}, including the important bright multiplets of C II at 1335 and

  12. Optic flow and the metric of the visual ground plane.

    PubMed

    Beusmans, J M

    1998-04-01

    A theory is developed in which the optic flow of an observer translating over the ground plane determines the metric of egocentric visual space. Optic flow is used to operationalize the equality of spatial intervals not unlike physicists use time to compare spatial intervals. The theory predicts empirical matching ratios for collinear, sagittal intervals to within 2% of the mean (eight subjects, standard error also 2%). The theory predicts that frontoparallel intervals on the ground plane will match sagittal intervals if their relative image motions match, which was found empirically. It is suggested that the optic flow metric serves to calibrate static depth cues such as angular elevation and binocular parallax.

  13. Sagittal geometry of the middle and lower cervical endplates.

    PubMed

    Chen, Hong; Zhong, Jian; Tan, Jixiang; Wu, Dandong; Jiang, Dianming

    2013-07-01

    Construct subsidence is a relatively common complication following anterior cervical fusion. Its occurrence has been revealed to be closely related to endplate-implant contact interface. But current literature focusing on the anatomy of cervical endplate is very scarce. The purpose of this morphometric study was to analyse the sagittal geometry, especially the concavity and slope, of vertebral endplates from C3 to C7 by employing data from CT scans. Reformatted CT scans of 97 individuals were analyzed and endplate concavity depth, endplate concavity apex location, as well as endplate slope were measured in midsagittal plane. Those specific parameters were compared among different age and gender groups. Meanwhile, comparison between superior and inferior endplate of each vertebra was also performed. Age and gender did not influence endplate concavity depth, endplate concavity apex location, or endplate slope significantly (P > 0.05). Endplate concavity depths of superior endplates (range 0.9-1.2 mm) were significantly smaller than those of inferior endplates (range 2.1-2.7 mm). Endplate concavity apex was always located in the posterior half of the endplate, with the superior one ranged from 56 to 67% and the inferior one 52 to 57%. Average endplate slopes of superior endplates were between 4.5° and 9.0°, and average inferior endplate slopes ranged from 4.5° to 7.5°. Among all measured segments, C5 had the largest endplate slope values, while C7 the least. Superior endplate is more flat than its inferior counterpart in middle and lower cervical spine, and the concavity apex is always located in the posterior half of the endplate. Endplate slope is correlated with cervical curvature, greater slope implying more significant lordosis. These sagittal endplate geometrical parameters should be taken into consideration when investigating implant subsidence following anterior cervical fusion.

  14. Coronal streamers' theories

    NASA Astrophysics Data System (ADS)

    Schultz, C. Göran

    1994-10-01

    Some theoretical aspects of solar coronal streamers are discussed with emphasis on the current sheet and reconnection processes going on along the axis of the streamer. The dynamics of the streamer is a combination of MHD and transport, with acceleration of particles due to reconnection and leakage of plasma outwards as a “slow” solar wind as the observable results. The presence of the almost-closed magnetic bottles of streamers that can store high-energy particles for significant times provides the birdcage for solar cosmic rays, the reconnection in the sheet feeds medium-energy protons into the corona for the large-scale storage needed for certain flare models, and the build-up of excess density sets the stage for coronal mass ejections.

  15. Analysis of sagittal balance of ankylosing spondylitis using spinopelvic parameters.

    PubMed

    Lee, Jung Sub; Suh, Kuen Tak; Kim, Jeung Il; Goh, Tae Sik

    2014-05-01

    Prospective study. To analyze sagittal spinopelvic parameters in ankylosing spondylitis (AS) patients. There are little data on the relationship between the sagittal spinopelvic parameters and AS. The study and control groups comprised 90 AS patients and 40 controls. Participants were classified into 3 groups: normal (n=40), sagittal balance (n=58), and sagittal imbalance (n=32) groups. All underwent lateral radiograph of the whole spine including hip joints. The radiographic parameters were sacral slope, pelvic tilting, pelvic incidence, overhang of S1, thoracic kyphosis, lumbar lordosis, and C7 plumbline. Statistical analysis was performed to identify significant differences between the 2 groups. Correlations between radiological parameters and symptoms were sought. AS patients and controls were found to be significantly different in terms of sagittal balance, sacral slope, pelvic tilt, pelvic incidence, S1 overhang, and lumbar lordosis. However, no significant difference was observed between these 2 groups for thoracic kyphosis (P>0.05). Of the 90 AS patients, 32 patients (5 women and 27 men) were assigned to the sagittal imbalance group and 58 (12 women and 46 men) to the sagittal balance group. There was a significant difference in all sagittal parameters and visual analogue scale (VAS) score between these 2 groups. Correlation analysis revealed significant relationships between sagittal parameters in AS. However, there was no association between sacral slope and S1 overhang, and between pelvic incidence and VAS score. Stepwise logistic regression analysis revealed that pelvic tilt contributed significantly to sagittal balance. AS patients and normal controls were found to be significantly different in terms of sagittal spinopelvic parameters. Significant relationships were found between sagittal spinopelvic parameters in AS patients. Pelvic tilt was a significant parameter in determination of sagittal balance in AS patient. Furthermore, VAS scores were

  16. Chromospheres of Coronal Stars

    NASA Technical Reports Server (NTRS)

    Linsky, Jeffrey L.; Wood, Brian E.

    1996-01-01

    We summarize the main results obtained from the analysis of ultraviolet emission line profiles of coronal late-type stars observed with the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope. The excellent GHRS spectra provide new information on magnetohydrodynamic phenomena in the chromospheres and transition regions of these stars. One exciting new result is the discovery of broad components in the transition region lines of active stars that we believe provide evidence for microflare heating in these stars.

  17. Coronal mass ejections

    SciTech Connect

    Steinolfson, R.S.

    1990-01-01

    Coronal mass ejections (CMEs) are now recognized as an important component of the large-scale evolution of the solar corona. Some representative observations of CMEs are reviewed with emphasis on more recent results. Recent observations and theory are examined as they relate to the following aspects of CMEs: (1) the role of waves in determining the white-light signature; and (2) the mechanism by which the CME is driven (or launched) into the corona.

  18. Coronal and interplanetary magnetic field models

    NASA Astrophysics Data System (ADS)

    Schatten, Kenneth H.

    1999-06-01

    We provide an historical perspective of coronal and interplanetary field models. The structure of the interplanetary medium is controlled by the coronal magnetic field from which the solar wind emanates. This field has been described with ``Source Surface'' (SS) and ``Heliospheric Current Sheet'' (HCS) models. The ``Source Surface'' model was the first to open the solar field into interplanetary space using volumetric coronal currents, which were a ``source'' for the IMF. The Heliospheric Current Sheet (HCS) model provided a more physically realistic solution. The field structure was primarily a dipole, however, without regard to sign, the shape appeared to be a monopole pattern (uniform field stress). Ulysses has observed this behavior. Recently, Sheeley and Wang have utilized the HCS field model to calculate solar wind structures fairly accurately. Fisk, Schwadron, and Zurbuchen have investigated small differences from the SS model. These differences allow field line motions reminiscent of a ``timeline'' or moving ``streakline'' in a flow field, similar to the smoke pattern generated by a skywriting plane. Differences exist in the magnetic field geometry, from the Parker ``garden hose'' model affecting both the ``winding angle'' as well as the amount of latitudinal ``wandering.''

  19. A comparison of anterior and posterior instrumentation for restoring and retaining sagittal balance in patients with idiopathic adolescent scoliosis.

    PubMed

    Tao, Fenghua; Wang, Zhiwei; Li, Ming; Pan, Feng; Shi, Zhicai; Zhang, Ye; Wu, Yungang; Xie, Yang

    2012-08-01

    Retrospective, comparative study. To compare the effects of anterior rod-screw instrumentation and posterior pedicle screw instrumentation on sagittal balance in patients with Lenke type 5 adolescent idiopathic scoliosis (AIS). Lenke type 5 AIS is treated by anterior or posterior spinal fusion surgery. Most studies comparing anterior and posterior fusion surgery have focused on assessing improvement in coronal balance. Studies comparing the effects of anterior and posterior surgery on sagittal balance are lacking. The records of 49 patients diagnosed with Lenke type 5 AIS were examined. A total of 21 patients underwent anterior surgery between 2000 and 2003, while 26 underwent posterior surgery between 2004 and 2006. Preoperative, postoperative, and follow-up thoracic kyphosis (T5-T12 and T2-T12), lumbar lordosis, thoracolumbar junction kyphosis, and spinal vertical axis measurements were made by examining radiographs. Quality of life was assessed using the Scoliosis Research Society-22 questionnaire. All patients were followed up for at least 2 years. There were no significant between group differences in coronal alignment, thoracic kyphosis, or T11-L2 alignment after surgery. Sagittal alignment improvement was significantly more pronounced in the anterior surgery group compared with the posterior surgery group. The fusion segment was also significantly shorter in the anterior surgery compared with the posterior surgery group. Quality of life scores were significantly higher in the anterior surgery group compared with the posterior surgery group. Anterior solid rod-screw instrumentation results in shorter fusion segments, and better sagittal alignment and quality of life than posterior pedicle screw instrumentation in patients with Lenke type 5 AIS.

  20. Atlas of axial, sagittal and coronal anatomy with CT and MRI

    SciTech Connect

    Christoforidis, A.J.

    1988-01-01

    This book correlates CT scans and nuclear magnetic resonance images with cross sections of all parts of the body-head and neck, thorax, abdomen, male and female pelvis and extremities. Cross sections are fixed, and images are made from the sections to provide exact section-to-scan correlation. Shows all three cross-sectional axes. Includes selected pathologic cases to demonstrate technique.

  1. Coronal Diagnostics Spectrometer Observations of Coronal Loops

    NASA Astrophysics Data System (ADS)

    Nasraoui, Kaouther; Schmelz, J. T.; Cirtain, J. W.; Del Zanna, G.; DeLuca, E. E.; Mason, H. E.

    2007-05-01

    Two side by side loops from the solar disk were analyzed. These two loops were observed with the Coronal Diagnostics Spectrometer on SOHO on 2003 January 17. The first loop was best seen in Mg IX at a wavelength of 368 angstroms and a peak formation temperature of Log T = 6.0. Seven pixels on the loop and one background pixel were chosen. The intensity of the background pixel was subtracted from each of the loop pixels. Only the lines that had a significant intensity after background subtraction were considered. A differential emission measure (DEM) curve was constructed for the background subtracted data using the forward folding technique. The DEM for most of these pixels had a spike shape at Log T equal to 5.85. This result shows that the loop is isothermal at most of these pixels. The second loop was best seen in Si XII at a wavelength of 520 angstroms and a peak formation temperature of Log T = 6.3. The same procedure was followed for the data analysis. After background subtraction only some hot lines had a significant intensity and a DEM curve was constructed for each loop pixel. This time the DEM is broader with a shape that shows that the loop plasma is multithermal with a log temperature range of 6.1 to 6.5. Solar physics research at the University of Memphis is supported by NSF ATM-0402729 and NASA NNG05GE68G.

  2. Image-optimized Coronal Magnetic Field Models

    NASA Astrophysics Data System (ADS)

    Jones, Shaela I.; Uritsky, Vadim; Davila, Joseph M.

    2017-08-01

    We have reported previously on a new method we are developing for using image-based information to improve global coronal magnetic field models. In that work, we presented early tests of the method, which proved its capability to improve global models based on flawed synoptic magnetograms, given excellent constraints on the field in the model volume. In this follow-up paper, we present the results of similar tests given field constraints of a nature that could realistically be obtained from quality white-light coronagraph images of the lower corona. We pay particular attention to difficulties associated with the line-of-sight projection of features outside of the assumed coronagraph image plane and the effect on the outcome of the optimization of errors in the localization of constraints. We find that substantial improvement in the model field can be achieved with these types of constraints, even when magnetic features in the images are located outside of the image plane.

  3. Effect of growing rod on sagittal and spinopelvic parameters in early-onset scoliosis patients.

    PubMed

    Sariyilmaz, Kerim; Akgul, Turgut; Ozkunt, Okan; Dikici, Fatih; Korkmaz, Murat; Sar, Cuneyt; Domanic, Unsal

    2016-05-01

    Growing rod is a commonly used surgery for early-onset scoliosis (EOS). However, the effect of growing-rod lengthening on the spinopelvic alignment is unclear. In this study, 21 EOS patients treated by growing rod were evaluated retrospectively and thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI) , sacral slope (SS), pelvic tilt (PT), and sagittal vertical axis (SVA) were measured. Preoperatively, the mean TK, LL, PI, PT, SS, and SVA were 27.4°, 35.2°, 43.8°, 7.5°, 33.8°, and 47.7 mm respectively. After the last lengthening, TK, LL, PI, PT, SS, and SVA were 28.3°, 28.06°, 41.4°, 7°, 5.2°, and 42.6 mm, respectively. The sagittal plane parameters in our EOS patients were not significantly altered during the lengthening period.

  4. CORONAL RAIN AS A MARKER FOR CORONAL HEATING MECHANISMS

    SciTech Connect

    Antolin, P.; Vissers, G.; Shibata, K. E-mail: g.j.m.vissers@astro.uio.n

    2010-06-10

    Reported observations in H{alpha}, Ca II H, and K or other chromospheric lines of coronal rain trace back to the days of the Skylab mission. Corresponding to cool and dense plasma, coronal rain is often observed falling down along coronal loops in active regions. A physical explanation for this spectacular phenomenon has been put forward thanks to numerical simulations of loops with footpoint-concentrated heating, a heating scenario in which cool condensations naturally form in the corona. This effect has been termed 'catastrophic cooling' and is the predominant explanation for coronal rain. In this work, we further investigate the link between this phenomenon and the heating mechanisms acting in the corona. We start by analyzing observations of coronal rain at the limb in the Ca II H line performed by the Hinode satellite, and derive interesting statistical properties concerning the dynamics. We then compare the observations with 1.5-dimensional MHD simulations of loops being heated by small-scale discrete events concentrated toward the footpoints (that could come, for instance, from magnetic reconnection events), and by Alfven waves generated at the photospheric level. Both our observation and simulation results suggest that coronal rain is a far more common phenomenon than previously thought. Also, we show that the structure and dynamics of condensations are far more sensitive to the internal pressure changes in loops than to gravity. Furthermore, it is found that if a loop is predominantly heated from Alfven waves, coronal rain is inhibited due to the characteristic uniform heating they produce. Hence, coronal rain may not only point to the spatial distribution of the heating in coronal loops but also to the agent of the heating itself. We thus propose coronal rain as a marker for coronal heating mechanisms.

  5. Modeling Coronal Jets with FLUX

    NASA Astrophysics Data System (ADS)

    Rachmeler, L. A.; Pariat, E.; Antiochos, S. K.; Deforest, C. E.

    2008-05-01

    We report on a comparative study of coronal jet formation with and without reconnection using two different simulation strategies. Coronal jets are features on the solar surface that appear to have some properties in common with coronal mass ejections, but are less energetic, massive, and broad. Magnetic free energy is built up over time and then suddenly released, which accelerates plasma outward in the form of a coronal jet. We compare results from the ARMS adaptive mesh and FLUX reconnection-less codes to study the role of reconnection in this system. This is the first direct comparison between FLUX and a numerical model with a 3D spatial grid.

  6. Which lateral radiographic positioning technique provides the most reliable and functional representation of a patient's sagittal balance?

    PubMed

    Marks, Michelle; Stanford, Chriss; Newton, Peter

    2009-04-20

    Prospective nonscoliotic cohort evaluation of the effects of various positions for obtaining standing lateral thoracolumbar radiographs. The purpose of this study was to compare the effects of various upper extremity positions on thoracolumbar sagittal spinal alignment. The standing position used to capture a lateral plane radiograph can have marked effects on measurements of sagittal spinal alignment and may compound the variability between measurements from successive radiographs. Twenty-two healthy female adolescents performed 3 repeated trials of 4 standing positions in a motion analysis laboratory. The positions included: (1) relaxed standing with arms at sides (CONTROL), (2) standing with fists overlying ipsilateral clavicles (CLAVICLE), (3) active shoulder flexion to 30 degrees with elbows extended (30 ACTIVE), and (4) passive shoulder flexion to 30 degrees with hand supports (30 PASSIVE). Sagittal alignment of the spine was described by kyphosis, lordosis, and the sagittal vertical axis (SVA), all of which were measured from the positions of reflective markers attached to the surface of the back and pelvis. Differences between alignment measures obtained for each of the 3 radiographic positions relative to the functional position (CONTROL) were calculated. Mean differences were then compared between positions using repeated measures ANOVAs (alpha = 0.05). Relative to the CONTROL position, all other positions resulted in negative shifts in SVA (range = -1.1 cm- -4.6 cm), decreased kyphosis (range = -1 degrees- -3 degrees), and increased lordosis (4 degrees for all positions). The shift in the SVA with the 30 PASSIVE position was significantly less than the other 2 positions (P < 0.05) and demonstrated the least variability. Standing with the hands supported while flexing the shoulders 30 degrees during positioning for lateral spinopelvic radiographic acquisition resulted in an SVA and measures of sagittal plane curvature that were comparable with a

  7. Determination of craniofacial relation among the subethnic Indian population: a modified approach - (Sagittal relation).

    PubMed

    Felicita, A Sumathi; Chandrasekar, Shyamala; Shanthasundari, K K

    2012-01-01

    To measure the linear cephalometric dimensions of anterior and posterior segments of the craniofacial complex sagittally, to establish ratios between different linear dimensions of sagittal segments and check for dimensional balance among the various segments in subjects with normal occlusion, pleasing profile and facial harmony. Department of Orthodontics, Saveetha University. Lateral cephalograms of 120 subjects of both sexes in the age group of 17-28 years with normal occlusion belonging to Chennai, India. Linear dimensions of anterior and posterior segments of the craniofacial complex were measured sagittally with the posterior maxillary plane as a key reference plane. Ratios were established between the various parameters in the anterior and posterior region. A ratio of 1:1 was found to exist between the individual and aggregate sagittal segments of the craniofacial complex in both sexes. There was a statistically significant sexual dimorphism in the aggregate lengths(P=0.028,P=0.005).However, the ratio between the anterior cranial floor and effective maxillary length was 2:3 and 5:8 and that between anterior cranial floor to effective mandibular length was 5:8 and 3:5 in females and males respectively. The difference in the above values was not statistically significant. A dimensional balance was found to exist between the maxilla and mandible both at the dentoalveolar and skeletal level with a ratio of 1:1. There was also a dimensional balance between the posterior cranial floor and ramus width. However, there was no architectural balance between the anterior cranial floor and maxilla and mandible.

  8. [The relationship between maxillary anterior impacted teeth and sagittal facial type].

    PubMed

    Tian, Yu-lou; Piao, Mei-ling; Zhao, Zhen-jin; Liu, Fang; Wang, Jing; Cao, Yu-ming

    2014-02-01

    To investigate the relationship between impaction of maxillary anterior teeth and sagittal facial type and evaluate the dentofacial morphological characteristics of patients with maxillary teeth impaction. Totally 90 patients with maxillary anterior teeth impaction were divided into 3 groups (one incisor impaction, one canine impaction and two canines impaction), and their cephalometric films were measured and analyzed. They were further divided into Class I, II and III facial types according to ANB and the constituent ratio were calculated. SPSS 17.0 software package was applied for Student's t test and chi-square test. SNA, A'-Ptm' and L1-NB were smaller than the normal value in the 3 groups. Convexity, L1-MP, ANB and Wits appraisal were smaller while AB plane angle, U1-NA and U1-NA were greater than the normal value in groups of one and two canines impaction; S'-Ptm', L1-NB were smaller while U1-L1 was greater than normal value in group of two canines impaction; Among the 3 groups, ANB and Wits appraisal were the smallest while AB plane angle was the greatest in group of two canines impaction. The sagittal facial type of 90 patients was mainly Class I (50%), but Class III in group of two canines impaction increased to 40%. Impacted maxillary anterior teeth might result in short maxillary basal bone. One canine impaction has the greatest influence than one incisor impaction on sagittal position of jaws. Two canines impaction has the greatest impact on sagittal facial type and tends to be Class III facial type.

  9. Muscle complex saving posterior sagittal anorectoplasty.

    PubMed

    Zaiem, Maher; Zaiem, Feras

    2017-05-01

    Posterior sagittal anorectoplasty (PSARP) published by DeVries and Peña in 1982 had become the preferred surgical technique for the management of anorectal malformations (ARM). The original technique is based upon complete exposure of the anorectal region by means of a median sagittal incision that runs from the sacrum to the anal dimple, cutting through all muscle structures behind the rectum by dividing the levator muscle and the muscle complex. Then, the rectum is located in front of the levator and within the limits of the muscle complex. In this review, we described Muscle Complex Saving-Posterior Sagittal Anorectoplasty (MCS-PSARP), which is a less invasive technique that consists of keeping this funnel-shaped muscle complex completely intact and not divided, and pulling the rectum through this funnel, toward fixing the new anus to the skin. This technique aimed both to respect the lower part of the sphincter mechanism consisting of the muscle complex, and to avoid the disturbance of this important structure by dividing and resuturing it. We presented six cases of male patients who were born with anorectal malformation (ARM) and underwent MCS-PSARP. The surgical technique proved to be feasible to achieve the dissection of the rectal pouch and the division of the rectourethral fistula in all patients, by opening only the upper part of the sphincter mechanism, the levator muscle, and keeping the lower part consisting of intact muscle complex. The early results in our series are encouraging; however, long-term functional outcomes of these patients are awaited. The surgical tips were also discussed. This proposed approach in the management of anorectal malformation cases provides an opportunity to maximize preservation of the existing continence mechanisms. It preserves the muscle complex components of the levator muscle intact, allowing a better function of the continence mechanism. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. CSF hydrodynamics in superior sagittal sinus thrombosis.

    PubMed Central

    Kristensen, B; Malm, J; Markgren, P; Ekstedt, J

    1992-01-01

    Cerebrospinal fluid hydrodynamics were investigated with a constant pressure infusion method in patients with superior sagittal sinus thrombosis. Ten patients were studied with serial examinations up to 15 years after the onset of the disease. A total of 70 CSF hydrodynamic examinations were performed. A clear increase in intracranial pressure due to raised pressure in the major dural sinus was seen in all patients. A striking feature was the persistent intracranial pressure increase that declined only gradually. This had no obvious clinical impact. Change in CSF resorption facility played only a minor role in the intracranial pressure elevation. None of the patients developed hydrocephalus. PMID:1583513

  11. Coronal and chromospheric physics

    NASA Technical Reports Server (NTRS)

    Jefferies, J. T.; Landman, D. A.; Orrall, F. Q.

    1983-01-01

    Achievements and completed results are discussed for investigations covering solar activity during the solar maximum mission and the solar maximum year; other studies of solar activity and variability; infrared and submillimeter photometry; solar-related atomic physics; coronal and transition region studies; prominence research; chromospheric research in quiet and active regions; solar dynamics; eclipse studies; and polarimetry and magnetic field measurements. Contributions were also made in defining the photometric filterograph instrument for the solar optical telescope, designing the combined filter spectrograph, and in expressing the scientific aims and implementation of the solar corona diagnostic mission.

  12. Value of sagittal color Doppler ultrasonography as a supplementary tool in the differential diagnosis of fetal cleft lip and palate

    PubMed Central

    2017-01-01

    Purpose The purpose of this study was to evaluate the feasibility and usefulness of sagittal color Doppler ultrasonography (CDUS) for the diagnosis of fetal cleft lip (CL) and cleft palate (CP). Methods We performed targeted ultrasonography on 25 fetuses with CL and CP, taking coronal and axial images of the upper lip and maxillary alveolar arch in each case. The existence of defects in and malalignment of the alveolus on the axial image, hard palate defects on the midsagittal image, and flow-through defects on CDUS taken during fetal breathing or swallowing were assessed. We compared the ultrasonography findings with postnatal findings in all fetuses. Results Alveolar defects were detected in 16 out of 17 cases with CP and four out of eight cases with CL. Alveolar malalignment and hard palate defects were detected in 11 out of 17 cases and 14 out of 17 cases with CP, respectively, but not detected in any cases with CL. Communicating flow through the palate defect was detected in 11 out of 17 cases of CL with CP. The accuracy of detection in axial scans of an alveolar defect and malalignment was 80% and 76%, respectively. Accuracy of detection of in mid-sagittal images of hard palate defect and flow was 80% and 86%, respectively. The overall diagnostic accuracy of combined axial and sagittal images with sagittal CDUS was 92%. Conclusion Sagittal CDUS of the fetal hard palate is a feasible method to directly reveal hard palate bony defects and flow through defects, which may have additional value in the differential diagnosis of fetal CL and CP. PMID:27764909

  13. Shock Formation of Slow Magnetosonic Waves in Coronal Plumes

    NASA Technical Reports Server (NTRS)

    Cuntz, Manfred; Suess, Steve; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We investigate the height of shock formation in coronal plumes for slow magnetosonic waves. The models take into account plume geometric spreading, heat conduction, and radiative damping. The wave parameters as well as the spreading functions of the plumes and the base magnetic field strengths are given by empirical constraints mostly from Solar and Heliospheric Observatory (SOHO)/ Ultraviolet Coronograph Spectrometer (UVCS), Extreme Ultraviolet Imaging Telescope (EIT), Michelson Doppler Imager (MDI), and Large Angle Spectrometric Coronagraph (LASCO). Our models show that shock formation occurs at relatively low coronal heights, typically within 1.2 RsuN, depending on the model parameters. The shock formation is calculated using the well-established wave breaking criterion given by the intersection of C+ characteristics in the space-time plane. Our models show that shock heating by slow magnetosonic waves is expected to be relevant at most heights in solar coronal plumes, although such waves are probably not the main energy supply mechanism.

  14. Shock Formation of Slow Magnetosonic Waves in Coronal Plumes

    NASA Technical Reports Server (NTRS)

    Cuntz, Manfred; Suess, Steven T.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    We investigate the height of shock formation in coroner plumes for slow magnetosonic waves. The models take into account plume geometric spreading, heat conduction and radiative damping. The wave parameters as well as the spreading functions of the plumes and the base magnetic field strengths are given by empirical constraints mostly from Solar and Heliospheric Observatory/Ultraviolet Coronagraph Spectrometer (SOHO/UVCS). Our models show that shock formation occurs at low coronal heights, i.e., within 1.3 solar radius, depending on the model parameters. The shock formation is calculated using the well-established wave breaking condition given by the intersection of C+ characteristics in the space-time plane. Our models show that shock heating by slow magnetosonic waves is expected to be relevant at most heights in solar coronal plumes, although slow magnetosonic waves are most likely not a solely operating energy supply mechanism.

  15. Shock Formation of Slow Magnetosonic Waves in Coronal Plumes

    NASA Technical Reports Server (NTRS)

    Cuntz, Manfred; Suess, Steve; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We investigate the height of shock formation in coronal plumes for slow magnetosonic waves. The models take into account plume geometric spreading, heat conduction, and radiative damping. The wave parameters as well as the spreading functions of the plumes and the base magnetic field strengths are given by empirical constraints mostly from Solar and Heliospheric Observatory (SOHO)/ Ultraviolet Coronograph Spectrometer (UVCS), Extreme Ultraviolet Imaging Telescope (EIT), Michelson Doppler Imager (MDI), and Large Angle Spectrometric Coronagraph (LASCO). Our models show that shock formation occurs at relatively low coronal heights, typically within 1.2 RsuN, depending on the model parameters. The shock formation is calculated using the well-established wave breaking criterion given by the intersection of C+ characteristics in the space-time plane. Our models show that shock heating by slow magnetosonic waves is expected to be relevant at most heights in solar coronal plumes, although such waves are probably not the main energy supply mechanism.

  16. Anterior sagittal transrectal approach (ASTRA) for vaginoplasty after complications of posterior sagittal anorectoplasty.

    PubMed

    de Jesus, Lisieux Eyer; Helman, Laura; Dekermacher, Samuel; Bernardo, Raquel L; Martinez, Cruz Delia M

    2013-01-01

    Transperineal exposure of the high portion of the vagina is limited. These limitations can be circumvented using ASTRA (anterior sagittal transrectal approach). We report the use of this surgical strategy for the treatment of a case of acquired vaginal atresia after posterior anorectoplasty due to anorectal malformation.

  17. Explaining Warm Coronal Loops

    NASA Technical Reports Server (NTRS)

    Klimchuk, James A.; Karpen, Judy T.; Patsourakos, Spiros

    2008-01-01

    One of the great mysteries of coronal physics that has come to light in the last few years is the discovery that warn (- 1 INK) coronal loops are much denser than expected for quasi-static equilibrium. Both the excess densities and relatively long lifetimes of the loops can be explained with bundles of unresolved strands that are heated impulsively to very high temperatures. Since neighboring strands are at different stages of cooling, the composite loop bundle is multi-thermal, with the distribution of temperatures depending on the details of the "nanoflare storm." Emission hotter than 2 MK is predicted, but it is not clear that such emission is always observed. We consider two possible explanations for the existence of over-dense warm loops without corresponding hot emission: (1) loops are bundles of nanoflare heated strands, but a significant fraction of the nanoflare energy takes the form of a nonthermal electron beam rather then direct plasma heating; (2) loops are bundles of strands that undergo thermal nonequilibrium that results when steady heating is sufficiently concentrated near the footpoints. We present numerical hydro simulations of both of these possibilities and explore the observational consequences, including the production of hard X-ray emission and absorption by cool material in the corona.

  18. Explaining Warm Coronal Loops

    NASA Technical Reports Server (NTRS)

    Klimchuk, James A.; Karpen, Judy T.; Patsourakos, Spiros

    2008-01-01

    One of the great mysteries of coronal physics that has come to light in the last few years is the discovery that warn (- 1 INK) coronal loops are much denser than expected for quasi-static equilibrium. Both the excess densities and relatively long lifetimes of the loops can be explained with bundles of unresolved strands that are heated impulsively to very high temperatures. Since neighboring strands are at different stages of cooling, the composite loop bundle is multi-thermal, with the distribution of temperatures depending on the details of the "nanoflare storm." Emission hotter than 2 MK is predicted, but it is not clear that such emission is always observed. We consider two possible explanations for the existence of over-dense warm loops without corresponding hot emission: (1) loops are bundles of nanoflare heated strands, but a significant fraction of the nanoflare energy takes the form of a nonthermal electron beam rather then direct plasma heating; (2) loops are bundles of strands that undergo thermal nonequilibrium that results when steady heating is sufficiently concentrated near the footpoints. We present numerical hydro simulations of both of these possibilities and explore the observational consequences, including the production of hard X-ray emission and absorption by cool material in the corona.

  19. Coronal Heating and Structure

    NASA Astrophysics Data System (ADS)

    Antiochos, S. K.

    2008-05-01

    The existence of the Sun's million-degree corona is one of the oldest and most challenging problems in all space physics. It is generally accepted that the solar magnetic field is responsible for both the heating and the structure of coronal plasma, but the physical mechanisms are still not clearly understood. Gene Parker has made many seminal contributions to solving the coronal heating problem, in particular, his widely-used nano-flare model. Parker argued that in closed field regions the complex motions of the photosphere must lead to the formation of fine-scale electric currents in the corona and, consequently, to continual bursts of magnetic reconnection. We discuss the implications of these ideas for understanding the observed features of the corona. We show that the type of reconnection proposed by Parker may well account for all the well-known observations of both the closed and open field corona, and we discuss the implications of our results for upcoming NASA missions. This work was supported by the NASA HTP and TR&T programs.

  20. Coronal Magnetic Field Models

    NASA Astrophysics Data System (ADS)

    Wiegelmann, Thomas; Petrie, Gordon J. D.; Riley, Pete

    2017-09-01

    Coronal magnetic field models use photospheric field measurements as boundary condition to model the solar corona. We review in this paper the most common model assumptions, starting from MHD-models, magnetohydrostatics, force-free and finally potential field models. Each model in this list is somewhat less complex than the previous one and makes more restrictive assumptions by neglecting physical effects. The magnetohydrostatic approach neglects time-dependent phenomena and plasma flows, the force-free approach neglects additionally the gradient of the plasma pressure and the gravity force. This leads to the assumption of a vanishing Lorentz force and electric currents are parallel (or anti-parallel) to the magnetic field lines. Finally, the potential field approach neglects also these currents. We outline the main assumptions, benefits and limitations of these models both from a theoretical (how realistic are the models?) and a practical viewpoint (which computer resources to we need?). Finally we address the important problem of noisy and inconsistent photospheric boundary conditions and the possibility of using chromospheric and coronal observations to improve the models.

  1. Coronal Rain, Solar Storm

    NASA Image and Video Library

    2017-09-28

    Explanation: In this picture, the Sun's surface is quite dark. A frame from a movie recorded on November 9th by the orbiting TRACE telescope, it shows coronal loops lofted over a solar active region. Glowing brightly in extreme ultraviolet light, the hot plasma entrained above the Sun along arching magnetic fields is cooling and raining back down on the solar surface. Hours earlier, on November 8th, astronomers had watched this particular active region produce a not so spectacular solar flare. Still, the M-class flare spewed forth an intense storm of particles, suddenly showering satellites near the Earth with high energy protons. The flare event was also associated with a large coronal mass ejection, a massive cloud of material which impacted our fair planet's magnetic field about 31 hours later. The result ... a strong geomagnetic storm. Credit: NASA/GSFC/TRACE To learn more go to: nasascience.nasa.gov/missions/trace To learn more about NASA's Sun Earth Day go here: sunearthday.nasa.gov/2010/index.php

  2. Sagittal spinopelvic alignment predicts hip function after total hip arthroplasty.

    PubMed

    Ochi, Hironori; Homma, Yasuhiro; Baba, Tomonori; Nojiri, Hidetoshi; Matsumoto, Mikio; Kaneko, Kazuo

    2017-02-01

    The aim of this study was to investigate the association between preoperative sagittal spinopelvic alignment and postoperative clinical outcomes after total hip arthroplasty (THA). This retrospective study included 92 patients with hip osteoarthritis who underwent primary THA between May 2013 and October 2015. Patients' characteristics, radiographic sagittal spinopelvic parameters and modified Harris Hip Scores, including function scores (gait scores and functional activities scores), were investigated. Multivariate linear regression analysis was performed to determine the associations between each preoperative sagittal spinopelvic parameter and postoperative hip function The preoperative sagittal spinopelvic parameters that were associated with postoperative gait scores were sagittal vertical axis (adjusted β-coefficient=-0.28, P=0.02), lumbar lordosis angle (adjusted β-coefficient=0.29, P=0.0089), pelvic tilt (adjusted β-coefficient=-0.25, P=0.045), sacral slope (adjusted β-coefficient=0.27, P=0.017) and pelvic incidence minus lumbar lordosis angle (adjusted β-coefficient=-0.31, P=0.01). The preoperative sagittal spinopelvic parameters that were related to the postoperative functional activities scores were sagittal vertical axis (adjusted β-coefficient=-0.38, P=0.0051) and pelvic incidence minus lumbar lordosis angle (adjusted β-coefficient=-0.39, P=0.0033). Patients with preoperative imbalanced sagittal alignment such as larger sagittal vertical axis, larger pelvic incidence minus lumbar lordosis and retroversion of pelvis had poorer clinical outcomes than others after THA. While, those preoperative imbalanced patients with anteversion of pelvis may have a compensatory ability which could correct the abnormal sagittal alignment after THA. Preoperative sagittal spinopelvic alignment affected postoperative clinical outcomes after THA. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Out-of-ecliptic studies of coronal holes and their relation to the solar wind. [project planning for solar probes to study solar activity

    NASA Technical Reports Server (NTRS)

    Noyes, R. W.

    1976-01-01

    The advantages of observing coronal holes of the sun above the solar ecliptic plane by a solar probe are discussed. Also discussed are the size of coronal holes, their temperature, and magnetic fields associated with the holes. The role of coronal holes in contributing to the solar wind is examined. Data and observations on coronal holes from Skylab and OSO are treated. It is concluded that an out-of-the-ecliptic solar probe mission would greatly add to the understanding of coronal holes (at high latitudes) thus adding a new perspective to the observation of these phenomena. (Photographs of the sun taken by Skylab are shown).

  4. The Geometric Spreading of Coronal Plumes and Coronal Holes

    NASA Technical Reports Server (NTRS)

    Suess, S. T.; Poletto, G.; Wang, A. - H.; Wu, S. T.; Cuseri, I.

    1997-01-01

    The geometric spreading in plumes and in the interplume region in coronal holes is calculated, using analytic and numerical theoretical models, between 1.0 and 5.0 solar radius. We apply two scale approximation that permits the rapid local spreading at the base of plumes to be evaluated separately from the global spreading imposed by coronal hole geometry. We show that fl can be computed from a potential field model and fg can be computed from global magnetohydrodynamic simulations of coronal structure. The approximations are valid when the plasma beta is small with respect to unity and for a plume separation small with respect to a solar radius.

  5. [Evaluation of the sagittal profile in patients with thoracic adolescent idiopathic scoliosis Lenke type 1 following posterior correction].

    PubMed

    Akbar, M; Dreher, T; Schwab, F; Omlor, G; Wang, H; Bruckner, T; Carstens, C; Wiedenhöfer, B

    2013-03-01

    The principle philosophy of posterior spinal instrumentation and fusion (PSIF) for the treatment of adolescent idiopathic scoliosis (AIS) has changed during recent decades. In the past the treatment of AIS mainly focused on correction of the major curve in the frontal plane while the sagittal profile and balancing were only of inferior interest in treatment planning. Various long-term outcome studies have demonstrated that many AIS patients developed a flatback syndrome (decrease of thoracic kyphosis and lumbar lordosis) associated with pain. It was concluded that treatment of AIS should consider the sagittal profile and balance; however, there are only few studies addressing additional procedures, which include the correction of the sagittal profile. The purpose of this study was to evaluate the effects of different posterior correction techniques on sagittal profile and balance. A total of 36 consecutive patients with thoracic AIS, who were treated with selective thoracic posterior correction were included in this retrospective study. The patients were further assigned to three different subgroups according to different surgical strategies: A: pedicle screws, B: long-head pedicle screws and C: additional Ponte osteotomy. Standardized radiographs in the standing position of the whole spine in two planes were evaluated before and at least 2 years after correction for all patients and a subgroup analysis was done to identify differences between the three groups. A significant correction of the major curve was achieved in all three groups (p < 0.001). There was a significant difference between the groups with groups B and C showing significantly higher levels of major curve correction in comparison to group A (p < 0.001). Concerning the sagittal profile, there was a significant difference in the development of thoracic kyphosis (TK) and lumbar lordosis (LL). While a significant reduction of TK and LL was found in groups A and B after surgery, a significant increase

  6. Internal derangements of the temporomandibular joint: diagnosis by direct sagittal computed tomography

    SciTech Connect

    Manzione, J.V.; Katzberg, R.W.; Brodsky, G.L.; Seltzer, S.E.; Mellins, H.Z.

    1984-01-01

    The authors performed direct sagittal computed tomography (CT) on 4 cadaver temporomandibular joints (TMJ) and examined 51 TMJs in 47 patients clinically. The results were correlated with cadaver anatomical sections and clinical arthrographic findings. A fat plane between the bellies of the lateral pterygoid muscles, termed the ''lateral pterygoid fat pad,'' served as the anatomical basis for detection of internal derangements by CT. CT was 94% accurate in detecting meniscal derangements and 96% accurate in detecting degenerative arthritis. The authors suggest that CT rather than arthrography be employed as the primary TMJ imaging modality when internal derangement or arthritis is suspected.

  7. Influence of hip replacement on sagittal alignment of the lumbar spine: An EOS study.

    PubMed

    Bredow, J; Katinakis, F; Schlüter-Brust, K; Krug, B; Pfau, D; Eysel, P; Dargel, J; Wegmann, K

    2015-01-01

    Changes in pelvic position can influence the sagittal alignment of the lumbar spine. The restoration of hip kinematics by hip replacement thus appears to offer the possibility of correcting sagittal alignment. This preliminary retrospective study used EOS imaging to investigate the influence of total hip arthroplasty on pelvic parameters in patients with normal preoperative pelvic parameters. Twenty patients with hip osteoarthritis undergoing total hip arthroplasty (THA) between 2011 and 2012 received unilateral THA. To evaluate the preoperative and postoperative changes of the pelvic parameters, we analyzed EOS imaging of the patients to determine pelvic incidence, sacral slope, sacral tilt, pelvic tilt, anterior pelvic plane inclination and pelvic axial rotation. Additionally, anteversion and inclination of the acetabular cup position were determined. No statistically significant difference was found between the preoperative and postoperative measurements of pelvic parameters, although the change in pelvic tilt approached significance. Postoperatively, respective average values of 42.6° and 22.7° were measured for inclination and anteversion of the acetabular cup position. THA did not influence pelvic position and sagittal alignment in patients with normal preoperative pelvic parameters. A subsequent study will investigate whether corrections of pelvic parameters outside the norm in patients with OA are possible with THA.

  8. The coronal fricative problem.

    PubMed

    Dinnsen, Daniel A; Dow, Michael C; Gierut, Judith A; Morrisette, Michele L; Green, Christopher R

    2013-07-01

    This paper examines a range of predicted versus attested error patterns involving coronal fricatives (e.g. [s, z, θ, ð]) as targets and repairs in the early sound systems of monolingual English-acquiring children. Typological results are reported from a cross-sectional study of 234 children with phonological delays (ages 3 years; 0 months to 7;9). Our analyses revealed different instantiations of a putative developmental conspiracy within and across children. Supplemental longitudinal evidence is also presented that replicates the cross-sectional results, offering further insight into the life-cycle of the conspiracy. Several of the observed typological anomalies are argued to follow from a modified version of Optimality Theory with Candidate Chains (McCarthy, 2007).

  9. The coronal fricative problem

    PubMed Central

    Dinnsen, Daniel A.; Dow, Michael C.; Gierut, Judith A.; Morrisette, Michele L.; Green, Christopher R.

    2013-01-01

    This paper examines a range of predicted versus attested error patterns involving coronal fricatives (e.g. [s, z, θ, ð]) as targets and repairs in the early sound systems of monolingual English-acquiring children. Typological results are reported from a cross-sectional study of 234 children with phonological delays (ages 3 years; 0 months to 7;9). Our analyses revealed different instantiations of a putative developmental conspiracy within and across children. Supplemental longitudinal evidence is also presented that replicates the cross-sectional results, offering further insight into the life-cycle of the conspiracy. Several of the observed typological anomalies are argued to follow from a modified version of Optimality Theory with Candidate Chains (McCarthy, 2007). PMID:24790247

  10. An overview of coronal seismology.

    PubMed

    De Moortel, I

    2005-12-15

    The idea of exploiting observed oscillations as a diagnostic tool for determining the physical conditions of the coronal plasma was first suggested several decades ago (Roberts et al. 1984 Astrophys. J. 279, 857). Until recently, the application of this idea has been very limited by a lack of high-quality observations of coronal oscillations. However, during the last few years, this situation has changed dramatically, especially due to space-based observations by the Solar and Heliospheric Observatory and the Transition Region and Coronal Explorer and waves and oscillations have now been observed in a wide variety of solar structures, such as coronal loops, polar plumes and prominences. This paper will briefly summarize MHD wave theory, which forms the basis for coronal seismology, as well as present an overview of the variety of recently observed waves and oscillations in the solar corona. The present state of coronal seismology will also be discussed. Currently, the uncertainty associated with the obtained parameters is still considerable and, hence, the results require a cautious interpretation. However, these examples do show that coronal seismology is rapidly being transformed from a theoretical possibility to a viable technique.

  11. The Coronal Solar Magnetism Observatory

    NASA Astrophysics Data System (ADS)

    Tomczyk, S.; Landi, E.; Zhang, J.; Lin, H.; DeLuca, E. E.

    2015-12-01

    Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required for advances in our understanding of the processes responsible for coronal heating, coronal dynamics and the generation of space weather that affects communications, GPS systems, space flight, and power transmission. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment, and to understand the formation of coronal mass ejections (CME) and their relation to other forms of solar activity. This new facility will be operated by the High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) with partners at the University of Michigan, the University of Hawaii and George Mason University in support of the solar and heliospheric community. It will replace the current NCAR Mauna Loa Solar Observatory (http://mlso.hao.ucar.edu). COSMO will enhance the value of existing and new observatories on the ground and in space by providing unique and crucial observations of the global coronal and chromospheric magnetic field and its evolution. The design and current status of the COSMO will be reviewed.

  12. Coronal transient--eruptive prominence of 1980 August 5

    SciTech Connect

    Fisher, R.; Garcia, C.J.; Seagraves, P.

    1981-06-15

    A coronal transient was observed in association with an eruptive prominence event using the Mauna Loa experiment system. The transient, a rarefaction, formed before the acceleration of the eruptive prominence. Upward velocities of various features, as seen in the plane of the sky, show a marked difference as a function of time between the transient and the eruptive prominence. A region of enhanced electron density formed slowly in front of the rarefaction.

  13. Ellis–van Creveld Syndrome with Sagittal Craniosynostosis

    PubMed Central

    Fischer, Andrew S.; Weathers, William M.; Wolfswinkel, Erik M.; Bollo, Robert J.; Hollier, Larry H.; Buchanan, Edward P.

    2014-01-01

    Ellis–van Creveld syndrome (EVC) is a rare disorder (the incidence is estimated at around 7/1,000,000) characterized by the clinical tetrad of chondrodystrophy, polydactyly, ectodermal dysplasia, and cardiac anomalies. Sagittal synostosis is characterized by a dolichocephalic head shape resulting from premature fusion of the sagittal suture. Both are rare disorders, which have never been reported together. We present a case of EVC and sagittal synostosis. We report the clinical features of a Hispanic boy with EVC and sagittal craniosynostosis who underwent cranial vault remodeling. The presentation of this patient is gone over in detail. A never before reported case of EVC and sagittal synostosis is presented in detail. PMID:26000085

  14. A Triumvirate: Three Coronal Holes

    NASA Image and Video Library

    2015-09-10

    Three substantial coronal holes rotated across the face of the Sun the week of Sept. 8-10, 2015 as seen by NASA Solar Dynamics Observatory. Coronal holes are areas where the Sun magnetic field is open and a source of streaming solar wind. They appear darker in extreme ultraviolet light because there is less material in the hole areas being imaged in this specific wavelength of light. It is a little unusual to have three coronal holes at the same time, but neither is it a rare occurrence. http://photojournal.jpl.nasa.gov/catalog/PIA19950

  15. Finite element analysis of sagittal balance in different morphotype: Forces and resulting strain in pelvis and spine.

    PubMed

    Filardi, Vincenzo; Simona, Portaro; Cacciola, Giorgio; Bertino, Salvatore; Soliera, Luigi; Barbanera, Andrea; Pisani, Alessandro; Milardi, Demetrio; Alessia, Bramanti

    2017-06-01

    In humans, vertical posture acquisition caused several changes in bones and muscles which can be assumed as verticalization. Pelvis, femur, and vertebral column gain an extension position which decreases muscular work by paravertebral muscles in the latter. It's widely known that six different morphological categories exist; each category differs from the others by pelvic parameters and vertebral column curvatures. Both values depend on the Pelvic Incidence, calculated as the angle between the axes passing through the rotation centre of the two femur heads and the vertical axis passing through the superior plate of the sacrum. The aim of this study is to evaluate the distribution of stress and the resulting strain along the axial skeleton using finite element analysis. The use of this computational method allows performing different analyses investigating how different bony geometries and skeletal structures can behavior under specific loading conditions. A computerized tomography (CT) of artificial bones, carried on at 1.5 mm of distance along sagittal, coronal and axial planes with the knee at 0° flexion (accuracy 0.5 mm), was used to obtain geometrical data of the model developed. Lines were imported into a commercial code (Hypermesh by Altair(®)) in order to interpolate main surfaces and create the solid version of the model. In particular six different models were created according Roussoly's classification, by arranging geometrical position of the skeletal components. Loading conditions were obtained by applying muscular forces components to T1 till to L5, according to a reference model (Daniel M. 2011), and a fixed constrain was imposed on the lower part of the femurs. Materials were assumed as elastic with an Elastic modulus of 15 GPa, a Shear Modulus of 7 GPa for bony parts, and an Elastic modulus of 6 MPa, a Shear Modulus of 3 MPa for cartilaginous parts. Six different simulations have been carried out in order to evaluate the mechanical behavior

  16. Craniotomy of the Fused Sagittal Suture Over the Superior Sagittal Sinus Is a Safe Procedure.

    PubMed

    Kölby, David; Fischer, Sara; Arab, Khalid; Maltese, Giovanni; Olsson, Robert; Paganini, Anna; Tarnow, Peter; Kölby, Lars

    2017-05-01

    Spring-assisted cranioplasty to correct sagittal synostosis is based on midline craniotomy through the closed sagittal suture, over the superior sagittal sinus (SSS). The aim of the present study was to evaluate the perioperative safety of this technique. This is a retrospective study of all patients operated with median craniotomy and springs from 1998 to the end of 2015. For comparison, all Pi-plasties performed during the same time interval were also evaluated. The safety measures were evaluated based on incidence of damage to SSS, incidence of dural tears, perioperative blood loss, operative time, and hospital stay. In the group that had undergone midline craniotomy combined with springs (n = 225), 4 perioperative damages to SSS and 1 dural tear were seen. The perioperative blood loss was 62.8 ± 65.3 mL (mean ± standard deviation). The operative time was 67.9 ± 21.5 minutes and the hospital stay was 4.8 ± 1.1 days. In the group that had undergone pi-plasty (n = 105), no damages to SSS but 3 dural tears were seen. The perioperative blood loss was 352.8 ± 174.4 mL. The operative time was 126.0 ± 31.7 minutes and the hospital stay was 7.1 ± 1.4 days. Craniotomy SSS in sagittal synostosis is a safe procedure with low morbidity in terms of damage to the SSS. Midline craniotomy combined with springs has significantly lower preoperative blood loss, operative time, and hospital stay (P < 0.001 for all) compared to pi-plasty.

  17. A novel mathematical model of the sagittal spine.

    PubMed

    Yang, Benson P; Yang, Carina W; Ondra, Stephen L

    2007-02-15

    Development of a mathematical model with application to a cohort of healthy volunteers. To derive a smooth mathematical function representing the sagittal spinal curve from individual vertebral elements. To generate normative data using this model. Current concepts of spinal sagittal balance center on the C7 plumb line. While elegant in its ease of use, this method oversimplifies the true complexity of the spine. If the spinal curve could be expressed as a smooth mathematical function, the ability to analyze sagittal balance would be greatly enhanced. Lateral full-length radiographs of 18 normal volunteers were examined. The posterosuperior aspect of each vertebral body was chosen as a representative point for the spinal sagittal curve. A cubic spline function was derived from these points. From this function, the area under the curve (AUC) and average sagittal positions of the thoracic, lumbar, and thoracolumbar segments were calculated. Assuming an average vertebral column height of 60 cm with anterior being positive, the average position of the posterosuperior aspect of C7 relative to S1 was -2.8 cm (+/-3.0). The average thoracolumbar AUC was -161 cm2 (+/-83). The average lumbar and thoracic AUCs were 0 cm2 (+/-17) and -157 cm2 (+/-68), respectively. The average sagittal position over the thoracolumbar curve was -3.3 cm (+/-1.7). The average sagittal positions of the lumbar and thoracic subcurves were 0.1 cm (+/-1.1) and -5.1 cm (+/-2.2), respectively. Intraobserver and interobserver reliabilities were excellent. A mathematical model of the sagittal spine that retains the spine's segmental nuances was derived using cubic spline interpolation. The average sagittal position of the thoracolumbar spine, a calculation based on the AUC, is a less variable measure of sagittal balance than the C7 plumb line. The model and normative data generated from it will allow more insightful investigations of spinal deformity and more quantitative evaluations of corrective

  18. Sagittal alignment correction of the thoracolumbar junction in idiopathic scoliosis by in situ bending technique.

    PubMed

    Charles, Y P; Meyer, N; Steib, J-P

    2008-01-01

    A long thoracolumbar sagittal rectitude is sometimes present in adolescent idiopathic scoliosis. The purpose of this study was to identify typical patterns, by comparing frontal plane deformities and vertebral rotation leading to this rectitude. Surgical thoracolumbar alignment correction by three-dimensional in situ bending of rods was then analyzed. Pre- and postoperative radiographs of 24 patients with scoliosis (36-104 degrees) were reviewed using Spineview software. Frontal curves and levels of sagittal rectitude were determined. Thoracic kyphosis, lumbar lordosis, sacral slope, pelvic incidence, pelvic tilt, T9 and T1 tilt were measured. Vertebral rotation was measured by computed tomography, Perdriolle's, Nash and Moe's methods. The intervertebral mobility of the rectitude was analyzed on side bending radiographs. Three patterns leading to sagittal rectitude were identified: 11 main thoracic curves (Lenke 1, King 3) with cranial prolongation of the physiological thoracolumbar junction (T7T12) and maximal vertebral rotation above this zone, 13 double major or thoracolumbar curves (Lenke 3 or 5, King 1 or 2) with cranial and caudal prolongation (T9L3) and maximal rotation above and below, 1 lumbar curve (Lenke 5) with caudal rectitude (T12L4) and maximal rotation at L1. There was no relationship between intervertebral mobility and rectitude. Postoperatively, this zone of rectitude disappeared in 17 out of 24 patients after anterior release followed by posterior instrumentation using the in situ bending technique. In situ bending realizes a stepwise correction of the three-dimensional deformity at different levels. An accurate preoperative analysis is mandatory to achieve an adequate sagittal balance, frontal curve correction and vertebral derotation simultaneously. The determined patterns of thoracolumbar rectitude are helpful to plan surgical correction accurately.

  19. Gender differences in sagittal standing alignment before pubertal peak growth: the importance of subclassification and implications for spinopelvic loading.

    PubMed

    Dolphens, Mieke; Cagnie, Barbara; Vleeming, Andry; Vanderstraeten, Guy; Danneels, Lieven

    2013-12-01

    The aim of this study was to analyze gender differences in sagittal standing alignment at pre-peak height velocity age thereby applying a scientifically sound and practically oriented classification scheme for overall standing balance. The study population consisted of healthy boys (n = 639) and girls (n = 557) before pubertal peak growth. During subjects' habitual standing, sagittal plane measures of the spine, pelvis and lower limbs were collected using a clinical screening protocol. With each subject classified as one of three postural types (neutral, sway-back, or leaning-forward), differences in sagittal plane alignment were analyzed between sexes. The results revealed clear differences between genders in each of the postural types. Within the neutral and sway-back postural subgroups, boys presented more forward inclination of the trunk, more thoracic kyphosis and more pelvis backtilt compared with girls. Within the leaning-forward category, girls displayed more forward trunk lean, less thoracic kyphosis and more pelvic anteversion. A state of lumbar segmental hyperextension appeared to exist in female leaning-forward subjects. Our results reveal for the first time that sagittal standing alignment is different between prepubescent boys and girls when subjects are appropriately subclassified, and conversely represent a 'wash-out effect' when pooled. When the classification system is applied, gender-specificity in gravity line position is suggested, implying gender-related differences in lever arms and thus load. Present findings may add to our understanding of gender-specific biomechanical challenges posed by habitual posture, and may shed new light on sagittal standing alignment as a possible contributory factor in developmental spinal-pelvic disorders.

  20. Solar and stellar coronal plasmas

    NASA Technical Reports Server (NTRS)

    Golub, L.

    1985-01-01

    Progress made in describing and interpreting coronal plasma processes and the relationship between the solar corona and its stellar counterparts is reported. Topics covered include: stellar X-ray emission, HEAO 2 X-ray survey of the Pleiades, closed coronal structures, X-ray survey of main-sequence stars with shallow convection zones, implications of the 1400 MHz flare emission, and magnetic field stochasticity.

  1. Identifying reproducible patterns of calvarial dysmorphology in nonsyndromic sagittal craniosynostosis may affect operative intervention and outcomes assessment.

    PubMed

    Schmelzer, Rodney E; Perlyn, Chad A; Kane, Alex A; Pilgram, Thomas K; Govier, Daniel; Marsh, Jeffrey L

    2007-04-15

    The authors tested the premise that there are four distinctive patterns of calvarial dysmorphology in nonsyndromic sagittal craniosynostosis that can be reproducibly recognized. Twenty-nine computed tomographic scan data sets of infants met the following criteria: nonsyndromic sagittal craniosynostosis, age younger than 12 months, and satisfactory computed tomographic data. Osseous reformations were constructed in the anteroposterior, right lateral, and vertex projections for each patient. From these images, four templates--coronal constriction, occipital protuberance, bifrontal bossing, and bitemporal protrusion--were selected as prototypes of the specific dysmorphologies the authors observed in patients with sagittal craniosynostosis. Four residents assigned the 29 calvarial image sets to one of the four templates or, if they were unable to do so, to the group "other." The sortings were then assessed for clustering. The same patient computed tomographic data were reformatted with osseous color images, which were then sorted according to template group by eight senior craniofacial surgeons, who repeated the task approximately 3 months later. The repeatability and assessment of clustering of image sets using the templates was evaluated. In the residents' pilot study, 41 percent (12 of 29) of patients had 100 percent concordance rates, 31 percent (nine of 29) had 75 percent concordance, 24 percent (seven of 29) had 50 percent, and 3 percent (one of 29) had 25 percent concordance. In summary, greater than 70 percent of the patient image sets could be sorted with at least 75 percent concordance by residents. In the senior surgeons' study, 90 percent of patients could be identified as falling into two of five possible groups. Senior raters demonstrated nearly 70 percent repeatability between sortings. These findings support the hypothesis that there are identifiable and reproducible patterns of varying calvarial dysmorphology in patients with sagittal craniosynostosis.

  2. The Holely Coronal Graveyard

    NASA Astrophysics Data System (ADS)

    Ayres, T.

    A 100 ks FUSE pointing will probe the O VI and C III emissions of an archetype denizen of the coronal graveyard--Aldebaran (Alpha Tauri; K5 III). HST spectra suggest the possible--surprising--presence of solar-like magnetic activity on the old, spun-down red giant. But, many of the characteristic 1150-1500 A UV emissions apparently are extinguished by a cool absorber overlying the hot (100,000 K) structures. Detection of O VI by FUSE suggests that the cool absorber opacity thins out just above the LyC edge, so O VI 1032 (and C III 977) could be a sensitive probe of the submerged activity through the far-UV opacity hole. The deep pointing will achieve high S/N, to search for discrete absorption structure in the hot lines, impressed on them by the cool absorber; and will allow an assessment of temporal variability due to the heating process, which might be convective-acoustic but probably is magnetic. If the latter, the buried magnetic activity on red giants possibly plays a key role in driving their winds--a long-standing astrophysical mystery, and a crucial component of galactic chemical evolution. The existing FUSE spectrum is too low in S/N to unambiguously measure discrete absorption components, and its singular nature precludes any variability analysis.

  3. Solar coronal jets

    NASA Astrophysics Data System (ADS)

    Dobrzyck, D.

    The solar jets were first observed by SOHO instruments (EIT, LASCO, UVCS) during the previous solar minimum. They were small, fast ejections originating from flaring UV bright points within large polar coronal holes. The obtained data provided us with estimates of the jet plasma conditions, dynamics, evolution of the electron temperature and heating rate required to reproduce the observed ionization state. To follow the polar jets through the solar cycle a special SOHO Joint Observing Program (JOP 155) was designed. It involves a number of SOHO instruments (EIT, CDS, UVCS, LASCO) as well as TRACE. The coordinated observations have been carried out since April 2002. The data enabled to identify counterparts of the 1996-1998 solar minimum jets. Their frequency of several events per day appear comparable to the frequency from the previous solar minimum. The jets are believed to be triggered by field line reconnection between emerging magnetic dipole and pre-existing unipolar field. Existing models predict that the hot jet is formed together with another jet of a cool material. The particular goal of the coordinated SOHO and TRACE observations was to look for possible association of the hot and cool plasma ejections. Currently there is observational evidence that supports these models.

  4. Sagittal Balance Correction in Lateral Interbody Fusion for Degenerative Scoliosis.

    PubMed

    Blizzard, Daniel J; Gallizzi, Michael A; Sheets, Charles; Smith, Benjamin T; Isaacs, Robert E; Eure, Megan; Brown, Christopher R

    2016-01-01

    Sagittal balance restoration has been shown to be an important determinant of outcomes in corrective surgery for degenerative scoliosis. Lateral interbody fusion (LIF) is a less-invasive technique which permits the placement of a high lordosis interbody cage without risks associated with traditional anterior or transforaminal interbody techniques. Studies have shown improvement in lumbar lordosis following LIF, but only one other study has assessed sagittal balance in this population. The objective of this study is to evaluate the ability of LIF to restore sagittal balance in degenerative lumbar scoliosis. Thirty-five patients who underwent LIF for degenerative thoracolumbar scoliosis from July 2013 to March 2014 by a single surgeon were included. Outcome measures included sagittal balance, lumbar lordosis, Cobb Angle, and segmental lordosis. Measures were evaluated pre-operative, immediately post-operatively, and at their last clinical follow-up. Repeated measures ANOVAs were used to assess the differences between pre-operative, first postoperative, and a follow-up visit. The average sagittal balance correction was not significantly different: 1.06cm from 5.79cm to 4.74cm forward. The average Cobb angle correction was 14.1 degrees from 21.6 to 5.5 degrees. The average change in global lumbar lordosis was found to be significantly different: 6.3 degrees from 28.9 to 35.2 degrees. This study demonstrates that LIF reliably restores lordosis, but does not significantly improve sagittal balance. Despite this, patients had reliable improvement in pain and functionality suggesting that sagittal balance correction may not be as critical in scoliosis correction as previous studies have indicated. LIF does not significantly change sagittal balance; however, clinical improvement does not seem to be contingent upon sagittal balance correction in the degenerative scoliosis population. The DUHS IRB has determined this study meets criteria for an IRB waiver.

  5. Sagittal Balance Correction in Lateral Interbody Fusion for Degenerative Scoliosis

    PubMed Central

    Gallizzi, Michael A.; Sheets, Charles; Smith, Benjamin T.; Isaacs, Robert E.; Eure, Megan; Brown, Christopher R.

    2016-01-01

    Background Sagittal balance restoration has been shown to be an important determinant of outcomes in corrective surgery for degenerative scoliosis. Lateral interbody fusion (LIF) is a less-invasive technique which permits the placement of a high lordosis interbody cage without risks associated with traditional anterior or transforaminal interbody techniques. Studies have shown improvement in lumbar lordosis following LIF, but only one other study has assessed sagittal balance in this population. The objective of this study is to evaluate the ability of LIF to restore sagittal balance in degenerative lumbar scoliosis. Methods Thirty-five patients who underwent LIF for degenerative thoracolumbar scoliosis from July 2013 to March 2014 by a single surgeon were included. Outcome measures included sagittal balance, lumbar lordosis, Cobb Angle, and segmental lordosis. Measures were evaluated pre-operative, immediately post-operatively, and at their last clinical follow-up. Repeated measures ANOVAs were used to assess the differences between pre-operative, first postoperative, and a follow-up visit. Results The average sagittal balance correction was not significantly different: 1.06cm from 5.79cm to 4.74cm forward. The average Cobb angle correction was 14.1 degrees from 21.6 to 5.5 degrees. The average change in global lumbar lordosis was found to be significantly different: 6.3 degrees from 28.9 to 35.2 degrees. Conclusions This study demonstrates that LIF reliably restores lordosis, but does not significantly improve sagittal balance. Despite this, patients had reliable improvement in pain and functionality suggesting that sagittal balance correction may not be as critical in scoliosis correction as previous studies have indicated. Clinical Relevance LIF does not significantly change sagittal balance; however, clinical improvement does not seem to be contingent upon sagittal balance correction in the degenerative scoliosis population. The DUHS IRB has determined this

  6. Accuracy of the Precision Saw versus the Sagittal Saw during total knee arthroplasty: A randomised clinical trial.

    PubMed

    Feczko, Peter Z; Fokkenrood, Hugo J P; van Assen, Tijmen; Deckers, Patrick; Emans, Pieter J; Arts, Jacobus J

    2017-10-01

    The aim of this study was to compare the accuracy of the oscillating tip saw system (Precision Saw=PS) with the more conventional fully oscillating blade system (Sagittal Saw=SS) during computer-assisted total knee arthroplasty (CAS-TKA). A prospective, randomised, controlled trial included 58 consecutive patients who underwent primary CAS-TKA and were randomly assigned in the PS group or the SS group to compare the accuracy of both blades. The primary outcome was the difference between the intended cutting planes and the actual cutting planes in degrees (°) in two planes of both the femur and the tibia. The secondary outcome was total surgery time. Tibia: In the VV-plane no significant differences were registered for the mean absolute deviation (p=0.28). The PS was more accurate in the AP-plane (p=0.03). Femur: The PS showed significantly fewer mean absolute deviations in the VV-plane (p=0.03); however, the SS revealed better accuracy in the FE-plane (p=0.04). The difference in the surgery time between the groups was not statistically significant (p=0.45). Two outliers were measured using the SS, while seven outliers were detected using the PS. The Precision Saw is not proven to be overall more accurate than the Sagittal Saw. Significantly better accuracy was shown with the PS in the two cutting planes, with the exception of one cutting plane that favoured the SS. Greater number of outliers were found using the PS. II. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Sagittal patellar tilt and concomitant quadriceps hypotrophy after tibial nailing.

    PubMed

    Aksahin, Ertugrul; Yilmaz, Serdar; Karasoy, Ismail; Duran, Semra; Yuksel, H Yalcin; Dogan, Ozgur; Yildirim, A Ozgur; Bicimoglu, Ali

    2016-09-01

    The aim of the study was to analyse the patellofemoral alignment in the sagittal plane following tibial fracture surgery with intramedullary nailing and its relationship to parapatellar muscle status. The patellofemoral MRI results of 27 patients (15 males and 12 females) treated with locked intramedullary nailing following tibia shaft fracture were reviewed. The mean age of the patients was 41.8 (±15) years. The patella-patellar tendon angle (P-PT) and the distance between the inferior patellar pole and the tibial tubercle (DP-TT) were evaluated for both the operated extremity and the contralateral normal side. MRI assessment of the infrapatellar fat pad, quadriceps, sartorius, gracilis, semi-membranosus muscles and biceps muscles was also carried out. The correlation between the changes in skeletal muscle mass, the volume of the infrapatellar fat pad and the alterations in the DP-TT distances and P-PT angles were analysed. The quadriceps muscle cross-sectional diameter had a mean of 157.2 mm(2) (115.6/319.5) in the operated extremity, and it was 193 mm(2) (77.6/282.2) in the non-operated normal side (p = 0.001). For the Gracilis muscle, the mean was 84.4 mm(2) (19.7/171) at the operated extremity and 75.7 mm(2) (26.9/238.2) on the normal side (p = 0.05). The cross-sectional areas of the semi-membranosus, sartorius and biceps muscles in the operated and non-operated extremity were not noticeably different (n.s). The P-PT angle was 153° (129.7/156.4) in the operated extremity and 145.7° (137.6/163.4) in the non-operated normal extremity (p < 0.05). While DP-TT distance was 11.4 mm (9.4/20.4) in the operated extremity, it was 14.1 mm (7.3/17.1) in the non-operated extremity (p = 0.001). The correlation analyses revealed that the quadriceps hypotrophy negatively correlated (r = -0.4, p = 0.02) with the P-PT angle but positively correlated with the increase in gracilis muscle volume (r = 0.4, p = 0.03). This study revealed that patellofemoral

  8. The Geometric Spreading of Coronal Plumes and Coronal Holes

    NASA Technical Reports Server (NTRS)

    Suess, S. T.; Poletto, G.; Wang, A.-H.; Wu, S. T.; Cuseri, I.

    1998-01-01

    The geometric spreading in plumes and in the interplume region in coronal holes is calculated, using analytic and numerical theoretical models, between 1.0 and 5.0 solar radius. We apply a two-scale approximation that permits the rapid local spreading at the base of plumes (f(sub t)) to be evaluated separately from the global spreading (f(sub g)) imposed by coronal hole geometry. We show that f(sub t) can be computed from a potential-field model and f(sub g) can be computed from global magnetohydrodynamic simulations of coronal structure. The approximations are valid when the plasma beta is mail with respect to unity and for a plume separation small with respect to a solar radius.

  9. Coronal Seismology -- Achievements and Perspectives

    NASA Astrophysics Data System (ADS)

    Ruderman, Michael

    Coronal seismology is a new and fast developing branch of the solar physics. The main idea of coronal seismology is the same as of any branches of seismology: to determine basic properties of a medium using properties of waves propagating in this medium. The waves and oscillations in the solar corona are routinely observed in the late space missions. In our brief review we concentrate only on one of the most spectacular type of oscillations observed in the solar corona - the transverse oscillations of coronal magnetic loops. These oscillations were first observed by TRACE on 14 July 1998. At present there are a few dozens of similar observations. Shortly after the first observation of the coronal loop transverse oscillations they were interpreted as kink oscillations of magnetic tubes with the ends frozen in the dense photospheric plasma. The frequency of the kink oscillation is proportional to the magnetic field magnitude and inversely proportional to the tube length times the square root of the plasma density. This fact was used to estimate the magnetic field magnitude in the coronal loops. In 2004 the first simultaneous observation of the fundamental mode and first overtone of the coronal loop transverse oscillation was reported. If we model a coronal loop as a homogeneous magnetic tube, then the ratio of the frequencies of the first overtone and the fundamental mode should be equal to 2. However, the ratio of the observed frequencies was smaller than 2. This is related to the density variation along the loop. If we assume that the corona is isothermal and prescribe the loop shape (usually it is assumed that it has the shape of half-circle), then, using the ratio of the two frequencies, we can determine the temperature of the coronal plasma. The first observation of transverse oscillations of the coronal loops showed that they were strongly damped. This phenomenon was confirmed by the subsequent observations. At present, the most reliable candidate for the

  10. Key aspects of coronal heating

    PubMed Central

    Klimchuk, James A.

    2015-01-01

    We highlight 10 key aspects of coronal heating that must be understood before we can consider the problem to be solved. (1) All coronal heating is impulsive. (2) The details of coronal heating matter. (3) The corona is filled with elemental magnetic stands. (4) The corona is densely populated with current sheets. (5) The strands must reconnect to prevent an infinite build-up of stress. (6) Nanoflares repeat with different frequencies. (7) What is the characteristic magnitude of energy release? (8) What causes the collective behaviour responsible for loops? (9) What are the onset conditions for energy release? (10) Chromospheric nanoflares are not a primary source of coronal plasma. Significant progress in solving the coronal heating problem will require coordination of approaches: observational studies, field-aligned hydrodynamic simulations, large-scale and localized three-dimensional magnetohydrodynamic simulations, and possibly also kinetic simulations. There is a unique value to each of these approaches, and the community must strive to coordinate better. PMID:25897094

  11. Ponderomotive Acceleration in Coronal Loops

    NASA Astrophysics Data System (ADS)

    Dahlburg, R. B.; Laming, J. M.; Taylor, B. D.; Obenschain, K.

    2016-11-01

    Ponderomotive acceleration has been asserted to be a cause of the first ionization potential (FIP) effect, the well-known enhancement in abundance by a factor of 3-4 over photospheric values of elements in the solar corona with FIP less than about 10 eV. It is shown here by means of numerical simulations that ponderomotive acceleration occurs in solar coronal loops, with the appropriate magnitude and direction, as a “by-product” of coronal heating. The numerical simulations are performed with the HYPERION code, which solves the fully compressible three-dimensional magnetohydrodynamic equations including nonlinear thermal conduction and optically thin radiation. Numerical simulations of coronal loops with an axial magnetic field from 0.005 to 0.02 T and lengths from 25,000 to 75,000 km are presented. In the simulations the footpoints of the axial loop magnetic field are convected by random, large-scale motions. There is a continuous formation and dissipation of field-aligned current sheets, which act to heat the loop. As a consequence of coronal magnetic reconnection, small-scale, high-speed jets form. The familiar vortex quadrupoles form at reconnection sites. Between the magnetic footpoints and the corona the reconnection flow merges with the boundary flow. It is in this region that the ponderomotive acceleration occurs. Mirroring the character of the coronal reconnection, the ponderomotive acceleration is also found to be intermittent.

  12. Influence of Coronal Abundance Variations

    NASA Technical Reports Server (NTRS)

    Gurman, Joseph (Technical Monitor); DeLuca, Edward

    2005-01-01

    During the final year of this program we concentrated on understanding the how to constrain the models with the best available observations. Work on developing accurate temperature and density diagnostics fkom TRACE and CDS together with constrained fits of non-potential force free fields will be extremely useful in the guiding the next generation of coronal models. The program has produced three fully operation numerical codes that model multi-species of ions in coronal loops: Static models and constant flow models. The time dependent numerical models have not been completed. We have extended the steady flow investigations to study the effect these flows have on coronal structure as observed with TRACE. Coronal observations derive from heavy-ion emission; thus, we focus on the extent to which flow may modify coronal abundances by examining the heavy-ion abundance stratification within long-lived loops. We discuss the magnitudes of the physical effects modeled and compare simulated results with TRACE observations. These results can have a profound effect on the interpretation of TRACE observations.

  13. Ponderomotive Acceleration in Coronal Loops

    NASA Astrophysics Data System (ADS)

    Dahlburg, Russell B.; Laming, J. Martin; Taylor, Brian; Obenschain, Keith

    2017-08-01

    Ponderomotive acceleration has been asserted to be a cause of the First Ionization Potential (FIP) effect, the by now well known enhancement in abundance by a factor of 3-4 over photospheric values of elements in the solar corona with FIP less than about 10 eV. It is shown here by means of numerical simulations that ponderomotive acceleration occurs in solar coronal loops, with the appropriate magnitude and direction, as a ``byproduct'' of coronal heating. The numerical simulations are performed with the HYPERION code, which solves the fully compressible three-dimensional magnetohydrodynamic equations including nonlinear thermal conduction and optically thin radiation. Numerical simulations of a coronal loops with an axial magnetic field from 0.005 Teslas to 0.02 Teslas and lengths from 25000 km to 75000 km are presented. In the simulations the footpoints of the axial loop magnetic field are convected by random, large-scale motions. There is a continuous formation and dissipation of field-aligned current sheets which act to heat the loop. As a consequence of coronal magnetic reconnection, small scale, high speed jets form. The familiar vortex quadrupoles form at reconnection sites. Between the magnetic footpoints and the corona the reconnection flow merges with the boundary flow. It is in this region that the ponderomotive acceleration occurs. Mirroring the character of the coronal reconnection, the ponderomotive acceleration is also found to be intermittent.

  14. Temporomandibular joint: true sagittal computed tomography with meniscus visualization

    SciTech Connect

    Sartorix, D.J.; Neumann, C.H.; Riley, R.W.

    1984-01-01

    Accessory patient support equipment was constructed that allows patient positioning for true sagittal projection of the temporomandibular joint using a GE 8800 CT/T scanner. Range of motion abnormalities, osseous alterations of the mandibular condyle and temporal bone, joint-space narrowing, and meniscal configuration may be demonstrated. The technique has potential advantages over other CT projections and sagittal reconstruction for evaluation of temporomandibular joint dysfunction.

  15. Coronal View Ultrasound Imaging of Movement in Different Segments of the Tongue during Paced Recital: Findings from Four Normal Speakers and a Speaker with Partial Glossectomy

    ERIC Educational Resources Information Center

    Bressmann, Tim; Flowers, Heather; Wong, Willy; Irish, Jonathan C.

    2010-01-01

    The goal of this study was to quantitatively describe aspects of coronal tongue movement in different anatomical regions of the tongue. Four normal speakers and a speaker with partial glossectomy read four repetitions of a metronome-paced poem. Their tongue movement was recorded in four coronal planes using two-dimensional B-mode ultrasound…

  16. Coronal View Ultrasound Imaging of Movement in Different Segments of the Tongue during Paced Recital: Findings from Four Normal Speakers and a Speaker with Partial Glossectomy

    ERIC Educational Resources Information Center

    Bressmann, Tim; Flowers, Heather; Wong, Willy; Irish, Jonathan C.

    2010-01-01

    The goal of this study was to quantitatively describe aspects of coronal tongue movement in different anatomical regions of the tongue. Four normal speakers and a speaker with partial glossectomy read four repetitions of a metronome-paced poem. Their tongue movement was recorded in four coronal planes using two-dimensional B-mode ultrasound…

  17. Determining the sagittal relationship between the maxilla and the mandible: a cephalometric analysis to clear up the confusion.

    PubMed

    Davis, Glen S; Cannon, James L; Messersmith, Marion L

    2013-01-01

    Establishing the sagittal jaw relationship is a key component to developing a diagnosis when treating an orthodontic patient. Several measurements, including the Wits Appraisal, ANB angle and nasion perpendicular have been and are currently used by practitioners to diagnose the sagittal jaw relationship. Unfortunately, all of these measurements have their limitations. The Cannon Analysis was created in an attempt to help overcome these limitations. One hundred untreated patients from the Vanderbilt University Medical Center database were selected, and their initial lateral cephalometric radiographs were digitally traced utilizing the Cannon Cephalometric Analysis. All of these patients had an orthognathic profile, a Class I occlusion and a good skeletal balance as judged by the authors. Normative values were established for the Cannon Analysis and then broken down by sex and age (8-11, 12-18, 19 and over). An example case was analyzed using the Cannon Analysis and several diagnostic scenarios were reviewed. The variance or difference between Porion to A Point (Po-A) and Porion to B Point (Po-B) was found to be 12.6 mm. This value remained relatively constant throughout life, with only slightly higher values for males versus females. The Cannon Analysis is an effective way to accurately establish the sagittal jaw relationship since it is not affected by the anterior / posterior position of nasion, the steepness of the mandibular plane angle, nor an improperly drawn occlusal plane.

  18. The effect of 3-column spinal osteotomy on anterior pelvic plane and acetabulum position.

    PubMed

    Schroeder, Josh E; Jerabek, Seth; Sama, Andrew; Kaplan, Leon; Girardi, Federico; Lebl, Darren R

    2014-07-01

    Because the spine and pelvis are integrated, changes in spine sagittal balance affect relative acetabulum position. A 1° change of the anterior pelvic plane changes acetabulum anteversion by 0.8°. Three-column spine osteotomies correct fixed sagittal plane deformity. Twenty patients with kyphotic deformity and associated sagittal imbalance underwent corrective 3-column osteotomy. We reviewed upright pelvic and spine radiographs preoperatively and postoperatively and documented the changes in angles. The average sagittal vertical axis was 11.07 cm preoperatively and 4.8 cm postoperatively. Lumbar lordosis changed (on average) from 39° preoperatively to 55° postoperatively (P < .05). Sacral slope increased an average of 6.7° (P = .015). Pelvic tilt decreased by 5.4° (P = .001). The anterior pelvic plane increased by 8.23° (P < .0001). This correction of the sagittal balance is associated with a concomitant increase in sacral slope, pelvic tilt, and the anterior pelvic plane angles. These changes will increase acetabulum anteversion by a predicted 6.54°. This increase will change acetabular cup position and must be considered in patients with spine and pelvic osteoarthritis that requires hip surgery.

  19. Fluctuating Asymmetry and Developmental Instability in Sagittal Craniosynostosis

    PubMed Central

    DeLeon, Valerie Burke; Richtsmeier, Joan T.

    2010-01-01

    Objective: To determine whether premature sagittal craniosynostosis is associated with developmental instability in the skull by analyzing fluctuating asymmetry in skull shape. Design: Cranial shape was quantified by collecting coordinate data from landmarks located on three-dimensional reconstructions of preoperative computed tomography (CT) images of 22 children with sagittal craniosynostosis and 22 age-matched controls. A fluctuating asymmetry application of Euclidean distance matrix analysis (EDMA) was used to quantify and compare asymmetry in cranial shape using these landmark data. Results: In contrast to expectations, the sagittal craniosynostosis group did not show a statistically significant increase in the overall level of fluctuating asymmetry relative to the control group. However, we discerned statistically significant localized increases in fluctuating asymmetry in the sagittal craniosynostosis group at pterion and the anterior clinoid processes (α = .05). We also determined a significant correlation of fluctuating asymmetry values between the two groups (r = .71). Conclusions: We conclude that there is no evidence of a role for system-wide developmental instability in the etiology of nonsyndromic sagittal craniosynostosis. However, the localized evidence of asymmetry at the anterior clinoid processes in the sagittal synostosis group suggests an association with the tracts of dura mater that attach there. PMID:19254065

  20. Solar Coronal Structure Study

    NASA Technical Reports Server (NTRS)

    Nitta, Nariaki; Bruner, Marilyn E.; Saba, Julia; Strong, Keith; Harvey, Karen

    2000-01-01

    The subject of this investigation is to study the physics of the solar corona through the analysis of the EUV and UV data produced by two flights (12 May 1992 and 25 April 1994) of the Lockheed Solar Plasma Diagnostics Experiment (SPDE) sounding rocket payload, in combination with Yohkoh and ground-based data. Each rocket flight produced both spectral and imaging data. These joint datasets are useful for understanding the physical state of various features in the solar atmosphere at different heights ranging from the photosphere to the corona at the time of the, rocket flights, which took place during the declining phase of a solar cycle, 2-4 years before the minimum. The investigation is narrowly focused on comparing the physics of small- and medium-scale strong-field structures with that of large-scale, weak fields. As we close th is investigation, we have to recall that our present position in the understanding of basic solar physics problems (such as coronal heating) is much different from that in 1995 (when we proposed this investigation), due largely to the great success of SOHO and TRACE. In other words, several topics and techniques we proposed can now be better realized with data from these missions. For this reason, at some point of our work, we started concentrating on the 1992 data, which are more unique and have more supporting data. As a result, we discontinued the investigation on small-scale structures, i.e., bright points, since high-resolution TRACE images have addressed more important physics than SPDE EUV images could do. In the final year, we still spent long time calibrating the 1992 data. The work was complicated because of the old-fashioned film, which had problems not encountered with more modern CCD detectors. After our considerable effort on calibration, we were able to focus on several scientific topics, relying heavily on the SPDE UV images. They include the relation between filaments and filament channels, the identification of hot

  1. Solar and stellar coronal plasmas

    NASA Technical Reports Server (NTRS)

    Golub, Leon

    1989-01-01

    Progress in observational, theoretical, and radio studies of coronal plasmas is summarized. Specifically work completed in the area of solar and stellar magnetic fields, related photospheric phenomena and the relationships between magnetism, rotation, coronal and chromospheric emission in solar-like stars is described. Also outlined are theoretical studies carried out in the following areas, among others: (1) neutral beams as the dominant energy transport mechanism in two ribbon-flares; (2) magneto hydrodynamic and circuit models for filament eruptions; and (3) studies of radio emission mechanisms in transient events. Finally, radio observations designed for coronal activity studies of the sun and of solar-type coronae are described. A bibliography of publications and talks is provided along with reprints of selected articles.

  2. Observational Analysis of Coronal Fans

    NASA Technical Reports Server (NTRS)

    Talpeanu, D.-C.; Rachmeler, L; Mierla, Marilena

    2017-01-01

    Coronal fans (see Figure 1) are bright observational structures that extend to large distances above the solar surface and can easily be seen in EUV (174 angstrom) above the limb. They have a very long lifetime and can live up to several Carrington rotations (CR), remaining relatively stationary for many months. Note that they are not off-limb manifestation of similarly-named active region fans. The solar conditions required to create coronal fans are not well understood. The goal of this research was to find as many associations as possible of coronal fans with other solar features and to gain a better understanding of these structures. Therefore, we analyzed many fans and created an overview of their properties. We present the results of this statistical analysis and also a case study on the longest living fan.

  3. Hybrid Stars and Coronal Evolution

    NASA Technical Reports Server (NTRS)

    Mushotzky, Richard (Technical Monitor); Dupree, Andrea K.

    2004-01-01

    This program addresses the evolution of stellar coronas by comparing a solar-like corona in the supergiant Dra (G2 Ib-IIa) to the corona in the allegedly more evolved state of a hybrid star, TrA (K2 11-111). Because the hybrid star has a massive wind, it appears likely that the corona will be cooler and less dense as the magnetic loop structures are no longer closed. By analogy with solar coronal holes, when the topology of the magnetic field is configured with open magnetic structures, both the coronal temperature and density are lower than in atmospheres dominated by closed loops. The hybrid stars assume a pivotal role in the definition of coronal evolution, atmospheric heating processes and mechanisms to drive winds of cool stars.

  4. Cascade model of coronal heating

    NASA Technical Reports Server (NTRS)

    Vanballegooijen, A. A.

    1986-01-01

    It is suggested that the quasi-static evolution of coronal magnetic structures is characterized by a cascade of magnetic energy to smaller length scales. This cascade process takes place on a time scale t sub b determined entirely by the photospheric motions. The Ohmic heating rate E sub H in the statistically stationary state was estimated using observational data on the diffusivity of photospheric motions; E sub H turned out to be too small by a factor of 40 when compared with observed coronal energy losses. However, given the fact that the theoretical estimate is based on a rather uncertain extrapolation to the diffusive regime, current heating cannot be ruled out as a viable mechanism of coronal heating.

  5. On-Disk Coronal Rain

    NASA Astrophysics Data System (ADS)

    Antolin, Patrick; Vissers, Gregal; Rouppe van der Voort, Luc

    2012-10-01

    Small and elongated, cool and dense blob-like structures are being reported with high resolution telescopes in physically different regions throughout the solar atmosphere. Their detection and the understanding of their formation, morphology, and thermodynamical characteristics can provide important information on their hosting environment, especially concerning the magnetic field, whose understanding constitutes a major problem in solar physics. An example of such blobs is coronal rain, a phenomenon of thermal non-equilibrium observed in active region loops, which consists of cool and dense chromospheric blobs falling along loop-like paths from coronal heights. So far, only off-limb coronal rain has been observed, and few reports on the phenomenon exist. In the present work, several data sets of on-disk Hα observations with the CRisp Imaging SpectroPolarimeter (CRISP) at the Swedish 1- m Solar Telescope (SST) are analyzed. A special family of on-disk blobs is selected for each data set, and a statistical analysis is carried out on their dynamics, morphology, and temperature. All characteristics present distributions which are very similar to reported coronal rain statistics. We discuss possible interpretations considering other similar blob-like structures reported so far and show that a coronal rain interpretation is the most likely one. The chromospheric nature of the blobs and the projection effects (which eliminate all direct possibilities of height estimation) on one side, and their small sizes, fast dynamics, and especially their faint character (offering low contrast with the background intensity) on the other side, are found as the main causes for the absence until now of the detection of this on-disk coronal rain counterpart.

  6. How is sagittal balance acquired during bipedal gait acquisition? Comparison of neonatal and adult pelves in three dimensions. Evolutionary implications.

    PubMed

    Tardieu, Christine; Bonneau, Noémie; Hecquet, Jérôme; Boulay, Christophe; Marty, Catherine; Legaye, Jean; Duval-Beaupère, Geneviève

    2013-08-01

    We compare adult and intact neonatal pelves, using a pelvic sagittal variable, the angle of sacral incidence, which presents significant correlations with vertebral curvature in adults and plays an important role in sagittal balance of the trunk on the lower limbs. Since the lumbar curvature develops in the child in association with gait acquisition, we expect a change in this angle during growth which could contribute to the acquisition of sagittal balance. To understand the mechanisms underlying the sagittal balance in the evolution of human bipedalism, we also measure the angle of incidence of hominid fossils. Fourty-seven landmarks were digitized on 50 adult and 19 intact neonatal pelves. We used a three-dimensional model of the pelvis (DE-VISU program) which calculates the angle of sacral incidence and related functional variables. Cross-sectional data from newborns and adults show that the angle of sacral incidence increases and becomes negatively correlated with the sacro-acetabular distance. During ontogeny the sacrum becomes curved, tends to sink down between the iliac blades as a wedge and moves backward in the sagittal plane relative to the acetabula, thus contributing to the backwards displacement of the center of gravity of the trunk. A chain of correlations links the degree of the sacral slope and of the angle of incidence, which is tightly linked with the lumbar lordosis. We sketch a model showing the coordinated changes occurring in the pelvis and vertebral column during the acquisition of bipedalism in infancy. In the australopithecine pelves, Sts 14 and AL 288-1, and in the Homo erectus Gona pelvis the angle of sacral incidence reaches the mean values of humans. Discussing the incomplete pelves of Ardipithecus ramidus, Australopithecus sediba and the Nariokotome Boy, we suggest how the functional linkage between pelvis and spine, observed in humans, could have emerged during hominid evolution.

  7. Comparison of the sagittal spine lordosis by supine computed tomography and upright conventional radiographs in patients with spinal trauma.

    PubMed

    Bouaicha, Samy; Lamanna, Claudia; Jentzsch, Thorsten; Simmen, Hans-Peter; Werner, Clément M L

    2014-01-01

    Retrospective data analysis. Objective. To compare the sagittal lordosis of the lumbar spine by supine computed tomography (CT) and upright conventional radiographs. There is sparse data about position and modality dependent changes of radiographic measurements in the sagittal lumbar spine. The anatomical and functional Cobb angles of the thoracolumbar spine in 153 patients with spinal injury were measured by conventional upright sagittal radiographs and supine CT scans. Patients were assigned either to group A (n = 101), with radiologically confirmed vertebral fractures, or to group B (n = 52), without any osseous lesions. The interchangeability of the two imaging modalities was calculated using a ± 3° and 5° range of acceptance. Group A showed a mean intraindividual difference of -3.8° for both the anatomical and the functional Cobb angle. Only 25.7% and 27.7% of the 101 patients showed a difference within the tolerated ± 3° margin. Using the ± 5° limits, only 46 and 47 individuals fell within the acceptable range, respectively. In the patients in group B, the mean intraindividual difference was -2.1° for the anatomical and -1.5° for the functional Cobb angle. Of the 52 patients, only 14 and 13 patients, respectively demonstrated an intraindividual difference within ± 3°. With regard to a threshold of ± 5°, both the functional and anatomical values were within the defined margins in only 25 (48%) patients. The use of supine CT measurements as a baseline assessment of the sagittal lordosis of the injured thoracolumbar spine does not appear to be appropriate when upright conventional sagittal plane radiographs are used for follow-up measurements.

  8. CORONAL FOURIER POWER SPECTRA: IMPLICATIONS FOR CORONAL SEISMOLOGY AND CORONAL HEATING

    SciTech Connect

    Ireland, J.; McAteer, R. T. J.; Inglis, A. R.

    2015-01-01

    The dynamics of regions of the solar corona are investigated using Atmospheric Imaging Assembly 171 Å and 193 Å data. The coronal emission from the quiet Sun, coronal loop footprints, coronal moss, and from above a sunspot is studied. It is shown that the mean Fourier power spectra in these regions can be described by a power law at lower frequencies that tails to a flat spectrum at higher frequencies, plus a Gaussian-shaped contribution that varies depending on the region studied. This Fourier spectral shape is in contrast to the commonly held assumption that coronal time series are well described by the sum of a long timescale background trend plus Gaussian-distributed noise, with some specific locations also showing an oscillatory signal. The implications of the observed spectral shape on the fields of coronal seismology and the automated detection of oscillations in the corona are discussed. The power-law contribution to the shape of the Fourier power spectrum is interpreted as being due to the summation of a distribution of exponentially decaying emission events along the line of sight. This is consistent with the idea that the solar atmosphere is heated everywhere by small energy deposition events.

  9. Sagittal spino-pelvic alignment failures following three column thoracic osteotomy for adult spinal deformity.

    PubMed

    Lafage, Virginie; Smith, Justin S; Bess, Shay; Schwab, Frank J; Ames, Christopher P; Klineberg, Eric; Arlet, Vincent; Hostin, Richard; Burton, Douglas C; Shaffrey, Christopher I

    2012-04-01

    Three column thoracic osteotomy (TCTO) is effective to correct rigid thoracic deformities, however, reasons for residual postoperative spinal deformity are poorly defined. Our objective was to evaluate risk factors for poor spino-pelvic alignment (SPA) following TCTO for adult spinal deformity (ASD). Multicenter, retrospective radiographic analysis of ASD patients treated with TCTO. Radiographic measures included: correction at the osteotomy site, thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic tilt (PT), and pelvic incidence (PI). Final SVA and PT were assessed to determine if ideal SPA (SVA < 4 cm, PT < 25°) was achieved. Differences between the ideal (IDEAL) and failed (FAIL) SPA groups were evaluated. A total of 41 consecutive ASD patients treated with TCTO were evaluated. TCTO significantly decreased TK, maximum coronal Cobb angle, SVA and PT (P < 0.05). Ideal SPA was achieved in 32 (78%) and failed in 9 (22%) patients. The IDEAL and FAIL groups had similar total fusion levels and similar focal, SVA and PT correction (P > 0.05). FAIL group had larger pre- and post-operative SVA, PT and PI and a smaller LL than IDEAL (P < 0.05). Poor SPA occurred in 22% of TCTO patients despite similar operative procedures and deformity correction as patients in the IDEAL group. Greater pre-operative PT and SVA predicted failed post-operative SPA. Alternative or additional correction procedures should be considered when planning TCTO for patients with large sagittal global malalignment, otherwise patients are at risk for suboptimal correction and poor outcomes.

  10. Earth-Directed Coronal Hole

    NASA Image and Video Library

    2016-09-21

    A dark coronal hole that was facing towards Earth for several days spewed streams of solar wind in our direction (Sept. 18-21, 2016). A coronal hole is a magnetically open region. The magnetic fields have opened up allowing solar wind (comprised of charged particles) to stream into space. Gusts of solar wind can generate beautiful aurora when they reach Earth. The video clip shows the sun in a wavelength of extreme ultraviolet light. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA21067

  11. Cascading Post-coronal Loops

    NASA Image and Video Library

    2017-04-24

    An active region that had just rotated into view blasted out a coronal mass ejection, which was immediately followed by a bright series of post-coronal loops seeking to reorganize that region's magnetic field (April 19, 2017). We have observed this phenomenon numerous times, but this one was one of the longest and clearest sequences we have seen in years. The bright loops are actually charged particles spinning along the magnetic field lines. The action was captured in a combination of two wavelengths of extreme ultraviolet light over a period of about 20 hours. Movies are available at https://photojournal.jpl.nasa.gov/catalog/PIA21598

  12. Earth-Facing Coronal Holes

    NASA Image and Video Library

    2016-11-09

    Two good-sized coronal holes have rotated around to the center of the sun where they will be spewing solar wind towards Earth (Nov. 8-9, 2016). Coronal holes are areas of open magnetic field from which solar wind particles stream into space. In this wavelength of extreme ultraviolet light they appear as the two dark areas at the center and lower portion of the sun. The stream of particles should reach Earth in a few days and are likely to generate aurora. Videos are available at http://photojournal.jpl.nasa.gov/catalog/PIA16909

  13. Evolution of a coronal streamer prior to mass ejection

    SciTech Connect

    Wolfson, R.; Conover, C.; Illing, R.M.E.

    1987-12-01

    We have developed a model describing the quasistatic evolution of a coronal helmet streamer as it is inflated with excess mass. The model produces a sequence of magnetostatic equilibria for a magnetic field configuration that includes a current sheet in the equatorial plane as well as distributed volume currents. The equilibrium solutions are given as Legendre series, and the height at which the current sheet starts is adjusted iteratively to maintain constant flux in the closed-field region. We have fit our model to SMM coronagraph/polarimeter observations showing the slow growth of a coronal streamer prior to its disruption in association with an eruptive prominence and mass ejection on August 18, 1980. The results suggest that the early phase of this event is consistent with the quasi-static evolution of the corona in response to the slow addition of mass to the closed-field region of the streamer.

  14. Solar wind flow upstream of the coronal slow shock

    NASA Technical Reports Server (NTRS)

    Whang, Y. C.

    1986-01-01

    Slow shocks have been predicted to exist embedded in large coronal holes at low altitude. Two or more curved slow shocks may link together to form a composite discontinuity surface around the sun which may be called the coronal slow shock (CSS). Here a solar-wind model is studied under the assumption that a standing CSS exists and cororates with the sun at a constant angular velocity. A steady, axisymmetrical one-fluid model is introduced to study the expansion of solar wind in the open-field region upstream of the CSS. The model requires that the conditions downstream of the CSS near the equatorial plane can produce a solar wind agreeable with the observations made near the earth's orbit. The paper presents an illustrative calculation in which the polar caps within 60 deg of the polar angle are assumed to be the source region of the solar wind.

  15. Three-dimensional reconstruction of coronal mass ejections

    NASA Technical Reports Server (NTRS)

    Jackson, Bernard V.; Hick, Paul

    1994-01-01

    Computer assisted tomography (CAT) techniques are used to reconstruct the three dimensional shape of coronal mass ejections in the interplanetary medium. Both the Helios 2 spacecraft zodiacal-light photometers and the Solwind coronograph measure changes in Thomson scattering of sunlight from electrons. The technique from near-perpendicular Solwind and Helios views are applied to determine the density of a mass ejection which left the solar surface on 24 May 1979. The coronograph and the Helios perspective views are not simultaneous; the Solwind observations extend outward to sky plane distances of only 10 of the solar radius, whereas the Helios 16 photometer observes to as close as 17 of the solar radius from the sun. The solution is obtained by assuming outward radial expansion and that the coronal mass ejections (CME's) have the same speed everywhere at the same height. The analyses show that CME's are extensive three dimensional structures (the CME of 24 May appears approximately shell) like in three dimensions.

  16. Analysis of muscle activity during active pelvic tilting in sagittal plane

    PubMed Central

    TAKAKI, Sho; KANEOKA, Koji; OKUBO, Yu; OTSUKA, Satoru; TATSUMURA, Masaki; SHIINA, Itsuo; MIYAKAWA, Shumpei

    2016-01-01

    Background: Pelvic tilting is performed to improve lumbopelvic flexibility or retrain the motor control of local muscles. However, few studies investigated the activity of local muscles during pelvic tilting. Purpose: The purpose of this study was to investigate muscle activity during anterior and posterior pelvic tilting. Method: Twelve healthy males (age, 22.6 ± 1.4 years) participated. Fine-wire electrodes were inserted into the bilateral lumbar multifidus (MF) and transversus abdominis (TrA). Surface electrodes were used to record activity of the bilateral rectus abdominis, external oblique, and erector spinae (ES), and the unilateral right latissimus dorsi, gluteus maximus, semitendinosus, and rectus femoris muscles. The electromyographic activities during anterior and posterior pelvic tilting in a standing position were recorded and expressed as a percentage of the maximum voluntary contraction (%MVC) for each muscle. Results: The activities of the bilateral MF (right: 23.9 ± 15.9 %MVC, left: 23.9 ± 15.1 %MVC) and right ES (19.0 ± 13.3 %MVC) were significantly greater than those of the other muscles during anterior pelvic tilting. The activity of the left TrA (14.8 ± 16.4 %MVC) was significantly greater than that of the other muscles during posterior pelvic tilting. Conclusions: The results suggested that the MF and ES are related to anterior pelvic tilting. The activity of the TrA, which was classified as a local muscle, was greater during posterior pelvic tilting. This study indicated that local muscles such as the MF and TrA may be related to pelvic tilting. PMID:28289581

  17. Sagittal plane joint kinetics during stair ascent in patients with peripheral arterial disease and intermittent claudication.

    PubMed

    King, Stephanie L; Vanicek, Natalie; O'Brien, Thomas D

    2017-06-01

    Stair negotiation poses a substantial physical demand on the musculoskeletal system and this challenging task can place individuals at risk of falls. Peripheral arterial disease (PAD) can cause intermittent claudication (IC) pain in the calf and results in altered gait mechanics during level walking. However, whether those with PAD-IC adopt alternate strategies to climb stairs is unknown. Twelve participants with PAD-IC (six bilateral and six unilateral) and 10 healthy controls were recruited and instructed to ascend a five-step staircase whilst 3D kinematic data of the lower-limbs were recorded synchronously with kinetic data from force plates embedded into the staircase on steps two and three. Limbs from the unilateral group and both limbs from the bilateral claudicants were categorised as claudicating (N=18), asymptomatic (N=6) and control (N=10). Claudicants walked more slowly than healthy controls (trend; P=<0.066). Both claudicating- and asymptomatic-limb groups had reduced propulsive GRF (P=0.025 and P=0.002, respectively) and vertical GRF (P=0.005 and P=0.001, respectively) compared to controls. The claudicating-limb group had a reduced knee extensor moment during forward continuance (P=0.060), ankle angular velocity at peak moment (P=0.039) and ankle power generation (P=0.055) compared to the controls. The slower gait speed, irrespective of laterality of symptoms, indicates functional capacity was determined by the limitations of the claudicating limb. Reduced ankle power generation and angular velocity (despite adequate plantarflexor moment) implies velocity-dependent limitations existed in the calf. The lack of notable compensatory strategies indicates reliance on an impaired muscle group to accomplish this potentially hazardous task, highlighting the importance of maintaining plantarflexor strength and power in those with PAD-IC. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. The back compressive forces during maximal push-pull activities in the sagittal plane.

    PubMed

    Kumar, S

    1994-12-01

    Ten normal young male and ten normal young female subjects (each group with a mean age of 21.1 years) performed isometric and isokinetic (50 cm per second) push and pull activity at 35 cm, 100 cm and 150 cm heights. The subjects were placed on a specially designed subject-stabilizing-platform to stabilize their lower extremities. Horizontal push-pull forces were exerted through a friction-reduced rod and sleeve assembly attached to the modified Static Dynamic Strength Tester. The strength measured by a SM 500 load cell was fed to an IBM XT through an A to D converter. The postural records were made on a videotape. The posture and strength were synchronized through an external light signal. The strength for pull activities was higher than the corresponding push activities (p < 0.01). The isometric strengths were significantly higher than the isokinetic strengths (p < 0.01). Though the push strengths were significantly lower than the pull strength, the low-back compressive forces for the push activities were 129% to 627% of the corresponding pull conditions. It is concluded that the push activities are more hazardous due to the higher magnitude of compressive load and their faster contribution to the threshold level of cumulative load leading to the precipitation of injuries.

  19. Experimental Evaluation of Balance Prediction Models for Sit-to-Stand Movement in the Sagittal Plane

    PubMed Central

    Pena Cabra, Oscar David; Watanabe, Takashi

    2013-01-01

    Evaluation of balance control ability would become important in the rehabilitation training. In this paper, in order to make clear usefulness and limitation of a traditional simple inverted pendulum model in balance prediction in sit-to-stand movements, the traditional simple model was compared to an inertia (rotational radius) variable inverted pendulum model including multiple-joint influence in the balance predictions. The predictions were tested upon experimentation with six healthy subjects. The evaluation showed that the multiple-joint influence model is more accurate in predicting balance under demanding sit-to-stand conditions. On the other hand, the evaluation also showed that the traditionally used simple inverted pendulum model is still reliable in predicting balance during sit-to-stand movement under non-demanding (normal) condition. Especially, the simple model was shown to be effective for sit-to-stand movements with low center of mass velocity at the seat-off. Moreover, almost all trajectories under the normal condition seemed to follow the same control strategy, in which the subjects used extra energy than the minimum one necessary for standing up. This suggests that the safety considerations come first than the energy efficiency considerations during a sit to stand, since the most energy efficient trajectory is close to the backward fall boundary. PMID:24187580

  20. Modeling effects of sagittal-plane hip joint stiffness on reciprocating gait orthosis-assisted gait.

    PubMed

    Johnson, William Brett; Fatone, Stefania; Gard, Steven A

    2013-01-01

    Upright ambulation is believed to improve quality of life for persons with lower-limb paralysis (LLP). However, ambulatory orthoses for persons with LLP, like reciprocating gait orthoses (RGOs), result in a slow, exhausting gait. Increasing the hip joint stiffness of these devices may improve the efficiency of RGO-assisted gait. The small, diverse population of RGO users makes subject recruitment challenging for clinical investigations. Therefore, we developed a lower-limb paralysis simulator (LLPS) that enabled nondisabled persons to exhibit characteristics of RGO-assisted gait, thereby serving as surrogate models for research. For this study, tests were conducted to determine the effects of increased hip joint stiffness on gait of nondisabled persons walking with the LLPS. A motion capture system, force plates, and spirometer were used to measure the hip flexion, crutch ground reaction forces (GRFs), and oxygen consumption of subjects as they walked with four different hip joint stiffness settings. Increasing the hip joint stiffness decreased hip flexion during ambulation but did not appear to affect the crutch GRFs. Walking speed was observed to initially increase with increases in hip joint stiffness, and then decrease. These findings suggest that increasing hip joint stiffness may increase walking speed for RGO users.

  1. Sagittal plane head stabilization during level walking and ambulation on stairs.

    PubMed

    Cromwell, R; Wellmon, R

    2001-01-01

    Head stabilization in space provides a stable reference frame for visual and vestibular systems during locomotor tasks. The purpose of the present study was to examine upper body movement patterns used to maintain head stability in response to the increased challenge of stair ambulation. A repeated-measures study design was used and the order of conditions was randomized for each subject. Eight healthy, non-disabled, young adults walked 10 metres on a level surface, ascended and descended four steps. Head, neck and trunk angular positions in space were obtained for three trials of each condition. Significant differences in mean head, neck and trunk angular orientation in space and segment excursions were determined. Cross-correlation analyses between head and neck, neck and trunk, and head and trunk determined movement patterns used for maintaining head stability. The chi-square test examined the homogeneity of movement pattern distributions for each segment pair across conditions. Head in space flexion orientation and angular excursions were greater during stair ascent and greater still during stair descent as compared to level walking. This indicates a progressively significant increase in the challenge to head stability. Neck flexion orientation in space and angular excursion were greater during stair descent as compared to level walking. Movement patterns between segment pairs demonstrated phase leads and lags between segments when threats to head stability were minimal. With increased challenge to head stability, segments moved synchronously in opposite directions to maintain balance. With further challenges to head stability, segments moved synchronously in the same direction to maintain body segment alignment. Head stabilization was significantly challenged when ascending stairs and is further challenged while descending stairs. Movement patterns reflected changes associated with challenges to head stability. Increased head excursion during stair ambulation may reflect the need to orient vision for foot placement. Results suggest that individuals with visual or vestibular deficits may be at risk for falls during stair ambulation.

  2. Predicting sagittal plane biomechanics that minimize the axial knee joint contact force during walking.

    PubMed

    Miller, Ross H; Brandon, Scott C E; Deluzio, Kevin J

    2013-01-01

    Both development and progression of knee osteoarthritis have been associated with the loading of the knee joint during walking. We are, therefore, interested in developing strategies for changing walking biomechanics to offload the knee joint without resorting to surgery. In this study, simulations of human walking were performed using a 2D bipedal forward dynamics model. A simulation generated by minimizing the metabolic cost of transport (CoT) resembled data measured from normal human walking. Three simulations targeted at minimizing the peak axial knee joint contact force instead of the CoT reduced the peak force by 12-25% and increased the CoT by 11-14%. The strategies used by the simulations were (1) reduction in gastrocnemius muscle force, (2) avoidance of knee flexion during stance, and (3) reduced stride length. Reduced gastrocnemius force resulted from a combination of changes in activation and changes in the gastrocnemius contractile component kinematics. The simulations that reduced the peak contact force avoided flexing the knee during stance when knee motion was unrestricted and adopted a shorter stride length when the simulated knee motion was penalized if it deviated from the measured human knee motion. A higher metabolic cost in an offloading gait would be detrimental for covering a long distance without fatigue but beneficial for exercise and weight loss. The predicted changes in the peak axial knee joint contact force from the simulations were consistent with estimates of the joint contact force in a human subject who emulated the predicted kinematics. The results demonstrate the potential of using muscle-actuated forward dynamics simulations to predict novel joint offloading interventions.

  3. The effect of thoracic kyphosis and sagittal plane alignment on vertebral compressive loading

    PubMed Central

    Bruno, Alexander G.; Anderson, Dennis E.; D’Agostino, John; Bouxsein, Mary L.

    2012-01-01

    To better understand the biomechanical mechanisms underlying the association between hyperkyphosis of the thoracic spine and risk of vertebral fracture and other degenerative spinal pathology, we used a previously validated musculoskeletal model of the spine to determine how thoracic kyphosis angle and spinal posture affect vertebral compressive loading. We simulated an age-related increase in thoracic kyphosis (T1-T12 Cobb angle 50° to 75°) during two different activities (relaxed standing and standing with 5 kg weights in the hands) and three different posture conditions: 1) an increase in thoracic kyphosis with no postural adjustment (uncompensated posture), 2) an increase in thoracic kyphosis with a concomitant increase in pelvic tilt that maintains a stable center of mass and horizontal eye gaze (compensated posture), and 3) an increase in thoracic kyphosis with a concomitant increase in lumbar lordosis that also maintains a stable center of mass and horizontal eye gaze (congruent posture). For all posture conditions, compressive loading increased with increasing thoracic kyphosis, with loading increasing more in the thoracolumbar and lumbar regions than in the mid-thoracic region. Loading increased the most for the uncompensated posture, followed by the compensated posture, with the congruent posture almost completely mitigating any increases in loading with increased thoracic kyphosis. These findings indicate that thoracic kyphosis and spinal posture both influence vertebral loading during daily activities, implying that thoracic kyphosis measurements alone are not sufficient to characterize the impact of spinal curvature on vertebral loading. PMID:22589006

  4. Knee and hip sagittal and transverse plane changes after two fatigue protocols

    PubMed Central

    Lucci, Shawn; Cortes, Nelson; Van Lunen, Bonnie; Ringleb, Stacie; Onate, James

    2013-01-01

    Fatigue has been shown to alter the biomechanics of lower extremity during landing tasks. To date, no study has examined the effects of two types of fatigue on kinetics and kinematics. Objectives This study was conducted to assess biomechanical differences between two fatigue protocols [Slow Linear Oxidative Fatigue Protocol (SLO-FP) and Functional Agility Short-Term Fatigue Protocol (FAST-FP)]. Design Single-group repeated measures design. Methods Fifteen female collegiate soccer players had to perform five successful trials of unanticipated sidestep cutting (SS) pre- and post-fatigue protocols. The SLO-FP consisted of an initial VO2peak test followed by 5-min rest, and a 30-min interval run. The FAST-FP consisted of 4 sets of a functional circuit. Biomechanical measures of the hip and knee were obtained at different instants while performing SS pre- and post-fatigue. Repeated 2 × 2 ANOVAs were conducted to examine task and fatigue differences. Alpha level set a priori at 0.05. Results During the FAST-FP, participants had increased knee internal rotation at initial contact (IC) (12.5 ± 5.9°) when compared to the SLO-FP (7.9 ± 5.4°, p < 0.001). For hip flexion at IC, pre-fatigue had increased angles (36.4 ± 8.4°) compared to post-fatigue (30.4 ± 9.3°, p = 0.003), also greater knee flexion during pre-fatigue (25.6 ± 6.8°) than post-fatigue (22.4 ± 8.4°, p = 0.022). Conclusion The results of this study showed that hip and knee mechanics were substantially altered during both fatigue conditions. PMID:21636322

  5. Comparison of parameters of spinal curves in the sagittal plane measured by photogrammetry and inclinometry.

    PubMed

    Walicka-Cupryś, Katarzyna; Drzał-Grabiec, Justyna; Mrozkowiak, Mirosław

    2013-10-31

    BACKGROUND. The photogrammetric method and inclinometer-based measurements are commonly employed to assess the anteroposterior curvatures of the spine. These methods are used both in clinical trials and for screening purposes. The aim of the study was to compare the parameters used to characterise the anteroposterior spinal curvatures as measured by photogrammetry and inclinometry. MATERIAL AND METHODS. The study enrolled 341 subjects: 169 girls and 172 boys, aged 4 to 9 years, from kindergartens and primary schools in Rzeszów. The anteroposterior spinal curvatures were examined by photogrammetry and with a mechanical inclinometer. RESULTS. There were significant differences in the α angle between the inclinometric and photogrammetric assessment in the Student t test (p=0.017) and the Fisher Snedecor test (p=0.0001), with similar differences in the β angle (Student's t p=0.0001, Fisher Snedecor p=0.007). For the γ angle, significant differences were revealed with Student's t test (p=0.0001), but not with the Fisher Snedecor test (p = 0.22). CONCLUSIONS. 1. Measurements of inclination of particular segments of the spine obtained with the photogrammetric method and the inclinometric method in the same study group revealed statistically significant differences. 2. The results of measurements obtained by photogrammetry and inclinometry are not comparable. 3. Further research on agreement between measurements of the anteroposterior spinal curvatures obtained using the available measurement equipment is recommended.

  6. Sagittal otolith morphogenesis asymmetry in marine fishes.

    PubMed

    Mille, T; Mahe, K; Villanueva, M C; De Pontual, H; Ernande, B

    2015-09-01

    This study investigated and compared asymmetry in sagittal otolith shape and length between left and right inner ears in four roundfish and four flatfish species of commercial interest. For each species, the effects of ontogenetic changes (individual age and total body length), sexual dimorphism (individual sex) and the otolith's location on the right or left side of the head, on the shape and length of paired otoliths (between 143 and 702 pairs according to species) were evaluated. Ontogenetic changes in otolith shape and length were observed for all species. Sexual dimorphism, either in otolith shape and length or in their ontogenetic changes, was detected for half of the species, be they round or flat. Significant directional asymmetry in otolith shape and length was detected in one roundfish species each, but its inconsistency across species and its small average amplitude (6·17% for shape and 1·99% for length) suggested that it has barely any biological relevance. Significant directional asymmetry in otolith shape and length was found for all flatfish species except otolith length for one species. Its average amplitude varied between 2·06 and 17·50% for shape and between 0·00 and 11·83% for length and increased significantly throughout ontogeny for two species, one dextral and one sinistral. The longer (length) and rounder otolith (shape) appeared to be always on the blind side whatever the species. These results suggest differential biomineralization between the blind and ocular inner ears in flatfish species that could result from perturbations of the proximal-distal gradient of otolith precursors in the endolymph and the otolith position relative to the geometry of the saccular epithelium due to body morphology asymmetry and lateralized behaviour. The fact that asymmetry never exceeded 18% even at the individual level suggests an evolutionary canalization of otolith shape symmetry to avoid negative effects on fish hearing and balance. Technically

  7. The dependence of coronal hole size on large scale magnetic field strength. [using a mathematical model of the photosphere

    NASA Technical Reports Server (NTRS)

    Suess, S. T.; Steinolfson, R. S.

    1980-01-01

    The importance of mathematical models of the coronal structure for studies of coronal energetics, to simulate global flows of the solar wind, and to obtain reliable solar terrestrial predictions is discussed. Previous coronal models, including an example of a coronal MHD flow model, are reviewed. The development of a coronal model which is a logical extension of earlier models and which allows a closer relationship to the photospheric magnetic field as it is observed daily is described. The calculations are outlined. The assumptions of the model are: axisymmetric flow with no rotation, resulting in two dimensional flow in a meridional plane; zero viscosity and infinite electrical conductivity; polytropic, single fluid flow; and no momentum addition.

  8. Is the sagittal postural alignment different in normal and dysphonic adult speakers?

    PubMed

    Franco, Débora; Martins, Fernando; Andrea, Mário; Fragoso, Isabel; Carrão, Luís; Teles, Júlia

    2014-07-01

    Clinical research in the field of voice disorders, in particular functional dysphonia, has suggested abnormal laryngeal posture due to muscle adaptive changes, although specific evidence regarding body posture has been lacking. The aim of our study was to verify if there were significant differences in sagittal spine alignment between normal (41 subjects) and dysphonic speakers (33 subjects). Cross-sectional study. Seventy-four adults, 35 males and 39 females, were submitted to sagittal plane photographs so that spine alignment could be analyzed through the Digimizer-MedCalc Software Ltd program. Perceptual and acoustic evaluation and nasoendoscopy were used for dysphonic judgments: normal and dysphonic speakers. For thoracic length curvature (TL) and for the kyphosis index (KI), a significant effect of dysphonia was observed with mean TL and KI significantly higher for the dysphonic speakers than for the normal speakers. Concerning the TL variable, a significant effect of sex was found, in which the mean of the TL was higher for males than females. The interaction between dysphonia and sex did not have a significant effect on TL and KI variables. For the lumbar length curvature variable, a significant main effect of sex was demonstrated; there was no significant main effect of dysphonia or significant sex×dysphonia interaction. Findings indicated significant differences in some sagittal spine posture measures between normal and dysphonic speakers. Postural measures can add useful information to voice assessment protocols and should be taken into account when considering particular treatment strategies. Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  9. A Comparative Study of Sagittal Balance in Patients with Neuromuscular Scoliosis.

    PubMed

    Borges, Paulo Alvim; Zelada, Flávio Gerardo Benites; Dos Santos Barros, Thiago Felipe; Letaif, Olavo Biraghi; da Rocha, Ivan Dias; Marcon, Raphael Martus; Cristante, Alexandre Fogaça; Barros-Filho, Tarcíso Eloy Pessoa

    2017-08-01

    Spinopelvic alignment has been associated with improved quality of life in patients with vertebral deformities, and it helps to compensate for imbalances in gait. Although surgical treatment of scoliosis in patients with neuromuscular spinal deformities promotes correction of coronal scoliotic deformities, it remains poorly established whether this results in large changes in sagittal balance parameters in this specific population. The objective of this study is to compare these parameters before and after the current procedure under the hypothesis is that there is no significant modification. Sampling included all records of patients with neuromuscular scoliosis with adequate radiographic records treated at Institute of Orthopedics and Traumatology of Clinics Hospital of University of São Paulo (IOT-HCFMUSP) from January 2009 to December 2013. Parameters analyzed were incidence, sacral inclination, pelvic tilt, lumbar lordosis, thoracic kyphosis, spinosacral angle, spinal inclination and spinopelvic inclination obtained using the iSite-Philips digital display system with Surgimap and a validated method for digital measurements of scoliosis radiographs. Comparison between the pre- and post-operative conditions involved means and standard deviations and the t-test. Based on 101 medical records only, 16 patients met the inclusion criteria for this study, including 7 males and 9 females, with an age range of 9-20 and a mean age of 12.9±3.06; 14 were diagnosed with cerebral palsy. No significant differences were found between pre and postoperative parameters. Despite correction of coronal scoliotic deformity in patients with neuromuscular deformities, there were no changes in spinopelvic alignment parameters in the group studied.

  10. Dynamics of Coronal Hole Boundaries

    NASA Astrophysics Data System (ADS)

    Higginson, A. K.; Antiochos, S. K.; DeVore, C. R.; Wyper, P. F.; Zurbuchen, T. H.

    2017-03-01

    Remote and in situ observations strongly imply that the slow solar wind consists of plasma from the hot, closed-field corona that is released onto open magnetic field lines. The Separatrix Web theory for the slow wind proposes that photospheric motions at the scale of supergranules are responsible for generating dynamics at coronal-hole boundaries, which result in the closed plasma release. We use three-dimensional magnetohydrodynamic simulations to determine the effect of photospheric flows on the open and closed magnetic flux of a model corona with a dipole magnetic field and an isothermal solar wind. A rotational surface motion is used to approximate photospheric supergranular driving and is applied at the boundary between the coronal hole and helmet streamer. The resulting dynamics consist primarily of prolific and efficient interchange reconnection between open and closed flux. The magnetic flux near the coronal-hole boundary experiences multiple interchange events, with some flux interchanging over 50 times in one day. Additionally, we find that the interchange reconnection occurs all along the coronal-hole boundary and even produces a lasting change in magnetic-field connectivity in regions that were not driven by the applied motions. Our results show that these dynamics should be ubiquitous in the Sun and heliosphere. We discuss the implications of our simulations for understanding the observed properties of the slow solar wind, with particular focus on the global-scale consequences of interchange reconnection.

  11. Coronal Heating by Magnetic Explosions

    NASA Technical Reports Server (NTRS)

    Moore, Ronald L.; Falconer, D. A.; Porter, Jason G.; Suess, Steven T.

    1998-01-01

    We build a case for the persistent strong coronal heating in active regions and the pervasive quasi-steady heating of the corona in quiet regions and coronal holes being driven in basically the same way as the intense transient heating in solar flares: by explosions of sheared magnetic fields in the cores of initially closed bipoles. We begin by summarizing the observational case for exploding sheared core fields being the drivers of a wide variety of flare events, with and without coronal mass ejections. We conclude that the arrangement of an event's flare heating, whether there is a coronal mass ejection, and the time and place of the ejection relative to the flare heating are all largely determined by four elements of the form and action the magnetic field: (1) the arrangement of the impacted, interacting bipoles participating in the event, (2) which of these bipoles are active (have sheared core fields that explode) and which are passive (are heated by injection from impacted active bipoles), (3) which core field explodes first, and (4) which core-field explosions are confined within the closed field of their bipoles and which ejectively open their bipoles.

  12. Coronal Dimmings and Energetic CMEs

    NASA Technical Reports Server (NTRS)

    Thompson, B. J.; Cliver, E. W.; Nitta, N.; Delannee, C.; Delaboudiniere, J.-P.

    1999-01-01

    We have analyzed the coronal dimmings for seven fast (> 600 km/s) coronal mass ejections (CMEs) occurring between 23 April and 9 May which were associated with flares from NOAA active region (AR) 8210. These dimming regions were identified by their strong depletion in coronal emission within a half hour of the estimated time of CME lift-off. They included areas which were as dark as quiescent coronal holes as well as other regions with weaker brightness depletions. We found that the extended dimming areas in these events generally mapped out the apparent "footprint" of the CME. In two of the seven cases, a pair of dimmings were more or less symmetrically positioned north and south of the flare site. In the five remaining cases, the dimmings were most prominent to the north of AR 8210 (approximately S15 latitude) and extended well north of the solar equator, consistent with the locations of the CMEs. We discuss the implications of these results for the sigmoid/double dimming/flux rope model of CMEs.

  13. CORONAL EMISSION LINES AS THERMOMETERS

    SciTech Connect

    Judge, Philip G.

    2010-01-10

    Coronal emission-line intensities are commonly used to measure electron temperatures using emission measure and/or line ratio methods. In the presence of systematic errors in atomic excitation calculations and data noise, the information on underlying temperature distributions is fundamentally limited. Increasing the number of emission lines used does not necessarily improve the ability to discriminate between different kinds of temperature distributions.

  14. Sagittal alignment of the cervical spine after neck injury.

    PubMed

    Beltsios, Michail; Savvidou, Olga; Mitsiokapa, Evanthia A; Mavrogenis, Andreas F; Kaspiris, Angelos; Efstathopoulos, Nikolaos; Papagelopoulos, Panayiotis J

    2013-07-01

    The normal sagittal alignment of the cervical spine is lordotic and is affected by the posture of the head and neck. The question of whether loss of cervical lordosis is the result of muscle spasm after injury or a normal variation, and the clinical significance of such changes in sagittal profile of the cervical spine has been an issue of several studies. The purpose of this paper is to study the incidence of normal cervical lordosis and its changes after neck injury compared to the healthy population. We studied the lateral radiographs of the cervical spine of 60 patients with neck injury compared to 100 patients without a neck injury. Lateral radiographs were obtained in the standing or sitting position, and the curvature of the cervical spine was measured using the angle formed between the inferior end plates of the C2 and C7 vertebrae. In the patients without neck injury, lordotic and straight cervical spine sagittal alignment was observed in 36.5% each, double curvature in 17%, and kyphotic in 10%. In the patients with neck injury, lordotic sagittal alignment was observed in 36%, straight in 34%, double curvature in 26% and kyphotic in 4%. No significant difference between the two groups regarding all types of sagittal alignment of the cervical spine was found (p > 0.100). The alterations in normal cervical lordosis in patients with neck injury must be considered coincidental. These alterations should not be associated with muscle spasm caused by neck pain.

  15. An equatorial coronal hole at solar minimum

    NASA Technical Reports Server (NTRS)

    Bromage, B. J. I.; DelZanna, G.; DeForest, C.; Thompson, B.; Clegg, J. R.

    1997-01-01

    The large transequatorial coronal hole that was observed in the solar corona at the end of August 1996 is presented. It consists of a north polar coronal hole called the 'elephant's trunk or tusk'. The observations of this coronal hole were carried out with the coronal diagnostic spectrometer onboard the Solar and Heliospheric Observatory (SOHO). The magnetic field associated with the equatorial coronal hole is strongly connected to that of the active region at its base, resulting in the two features rotating at almost the same rate.

  16. Evaluation of dental maturation in children according to sagittal jaw relationship

    PubMed Central

    Esenlik, Elcin; Atak, Aslihan; Altun, Ceyhan

    2014-01-01

    Objective: The aims of this retrospective study were to determine compliance with dental and chronological ages and to analyze the relationships between dental age and orthodontic sagittal anomalies. Materials and Methods: A total of 221 subjects between the ages of 7 and 15.9 years (165 girls and 156 boys) were included in the study. The dental age of seven left mandibular teeth was assessed according to the Demirjian method. The maxillary protrusion, mandibular protrusion, maxillo-mandibular and vertical plane angles were measured from cephalometric films. Results: The mean difference between the chronological age and dental age in female patients was 0.94 years and 0.33 years in male patients (P < 0.01). No differences between the sagittal classification groups were found. There was no relationship between dental age and the SNA° or the GoGn-SN°. A statistically significant negative relationship was found between dental age and the SNB° and there was a significant linear relationship between dental age and the ANB°. Conclusion: Dental age in girls and boys has been estimated to be more advanced than chronological age in all classes and dental maturation advanced in cases with a tendency to develop Class II malocclusions. PMID:24966744

  17. Evaluation of dental maturation in children according to sagittal jaw relationship.

    PubMed

    Esenlik, Elcin; Atak, Aslihan; Altun, Ceyhan

    2014-01-01

    The aims of this retrospective study were to determine compliance with dental and chronological ages and to analyze the relationships between dental age and orthodontic sagittal anomalies. A total of 221 subjects between the ages of 7 and 15.9 years (165 girls and 156 boys) were included in the study. The dental age of seven left mandibular teeth was assessed according to the Demirjian method. The maxillary protrusion, mandibular protrusion, maxillo-mandibular and vertical plane angles were measured from cephalometric films. The mean difference between the chronological age and dental age in female patients was 0.94 years and 0.33 years in male patients (P < 0.01). No differences between the sagittal classification groups were found. There was no relationship between dental age and the SNA° or the GoGn-SN°. A statistically significant negative relationship was found between dental age and the SNB° and there was a significant linear relationship between dental age and the ANB°. Dental age in girls and boys has been estimated to be more advanced than chronological age in all classes and dental maturation advanced in cases with a tendency to develop Class II malocclusions.

  18. Coronal Fourier power spectra: implications for coronal heating and coronal seismology

    NASA Astrophysics Data System (ADS)

    Ireland, J.; Mcateer, R. T. J.; Inglis, A. R.

    2014-12-01

    The dynamics of regions of the solar corona are investigated using AIA 171 and 193 Angstrom data. It is shown that the mean Fourier power spectra of emission from active region cores, above sunspots, in loop footpoints and in the quiet Sun, follow an approximate power-law behaviour. We show that power-law power-spectra can be formed by summing a distribution of exponentially decaying emission events along the line of sight, consistent with the idea that the corona is heated everywhere by small energy deposition events. We also examine changes in Fourier power spectrum as a function of coronal loop height to look for evidence of a preferred location to coronal heating. The observed power-law power spectra also have implications for coronal seismology, as all existing observational studies do not take into account the power-law power spectrum of the coronal emission and its attendant statistical properties. We show that random fluctuations in the emission can be mis-identified as oscillatory signal, and give suggestions on how to detect oscillatory motions above a background power-law power spectrum.

  19. Sagittal Fresh Blood Imaging with Interleaved Acquisition of Systolic and Diastolic Data for Improved Robustness to Motion

    PubMed Central

    Atanasova, Iliyana P.; Kim, Daniel; Storey, Pippa; Rosenkrantz, Andrew B; Lim, Ruth P.; Lee, Vivian S.

    2012-01-01

    Purpose To improve robustness to patient motion of ‘fresh blood imaging’ (FBI) for lower extremity non-contrast MRA. Methods In FBI, two sets of 3D fast spin echo images are acquired at different cardiac phases and subtracted to generate bright-blood angiograms. Routinely performed with a single coronal slab and sequential acquisition of systolic and diastolic data, FBI is prone to subtraction errors due to patient motion. In this preliminary feasibility study, FBI was implemented with two sagittal imaging slabs, and the systolic and diastolic acquisitions were interleaved to minimize sensitivity to motion. The proposed technique was evaluated in volunteers and patients. Results In ten volunteers, imaged while performing controlled movements, interleaved FBI demonstrated better tolerance to subject motion than sequential FBI. In one patient with peripheral arterial disease, interleaved FBI offered better depiction of collateral flow by reducing sensitivity to inadvertent motion. Conclusions FBI with interleaved acquisition of diastolic and systolic data in two sagittal imaging slabs offers improved tolerance to patient motion. PMID:23300129

  20. Denonvilliers' fascia in men: a sheet plastination and confocal microscopy study of the prerectal space and the presence of an optimal anterior plane when mobilizing the rectum for cancer.

    PubMed

    Xu, Zhaoyang; Chapuis, Pierre H; Bokey, Les; Zhang, Ming

    2017-10-04

    The aim of this study was to investigate the detailed, in situ, morphology of Denonvilliers fascia (DVF) in cadavers using sheet plastination and confocal microscopy and to review and describe the optimal anterior plane for mobilisation of the distal rectum.. Six, male cadavers (age range, 46-87 years) were prepared as six sets of transverse (x2), coronal (x1) and sagittal (x3) plastinated sections which were examined under a confocal laser scanning microscope. In this study a consistent space between the anterior rectal wall and the posterior surface of the prostate and seminal vesicles above the level of the perineal body was termed the prerectal space. Within that prerectal space we identified fibres which take their origin from the external urethral sphincter (EUS), together with others from the longitudinal rectal muscle (LRM) and the connective tissue sheaths of neurovascular bundles. Neither the EUS- nor the LRM-originated fibres were continuous with the endopelvic fascia;they are interposed laterally and cranially by multiple neurovascular bundles. Further, our results suggest that the peritoneum does not descend deep within the prerectal space. This study reveals the undisturbed, in situ, structural detail of membrane-like structures in the prerectal space and confirms that the optimal plane for anterolateral mobilization of the rectum is posterior to the multilayered DVF. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Surgical Correction of Nonsyndromic Sagittal Craniosynostosis: Concepts and Controversies.

    PubMed

    Simpson, Andrew; Wong, Alison L; Bezuhly, Michael

    2017-01-01

    Sagittal craniosynostosis remains the most common type of isolated craniosynostosis, accounting for nearly half of all nonsyndromic cases. The clinical diagnosis is typically made on the basis of a scaphocephalic head shape and is confirmed by computed tomography or magnetic resonance imaging. The current review examines the major surgical options for correction of isolated sagittal craniosynostosis, including their complications and short- and long-term outcomes. Reconstructive techniques have benefited from advances in perioperative anesthesia monitoring and improved safety of blood transfusion. Although extensive calvarial remodeling is considered safe and may confer greater long-term skull shape correction and decreased neuropsychological sequelae, minimally invasive techniques, such as device-assisted expansion of the cranium continue to increase in popularity. This review underscores the need for additional prospective studies comparing different techniques to determine the optimal reconstructive approach for correction of sagittal craniosynostosis.

  2. Pre-flare coronal dimmings

    NASA Astrophysics Data System (ADS)

    Zhang, Q. M.; Su, Y. N.; Ji, H. S.

    2017-01-01

    Context. Coronal dimmings are regions of decreased extreme-ultravoilet (EUV) and/or X-ray (originally Skylab, then Yohkoh/SXT) intensities, which are often associated with flares and coronal mass ejections (CMEs). The large-scale impulsive dimmings have been thoroughly observed and investigated. The pre-flare dimmings before the flare impulsive phase, however, have rarely been studied in detail. Aims: We focus on the pre-flare coronal dimmings. We report our multiwavelength observations of the GOES X1.6 solar flare and the accompanying halo CME that was produced by the eruption of a sigmoidal magnetic flux rope (MFR) in NOAA active region (AR) 12158 on 2014 September 10. Methods: The eruption was observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO). The photospheric line-of-sight magnetograms were observed by the Helioseismic and Magnetic Imager (HMI) on board SDO. The soft X-ray (SXR) fluxes were recorded by the GOES spacecraft. The halo CME was observed by the white-light coronagraphs of the Large Angle Spectroscopic Coronagraph (LASCO) on board SOHO. Results: About 96 min before the onset of the flare/CME, narrow pre-flare coronal dimmings appeared at the two ends of the twisted MFR. They extended very slowly, with their intensities decreasing with time, while their apparent widths (8-9 Mm) continued to be nearly constant. During the impulsive and decay phases of flare, typical fan-like twin dimmings appeared and expanded, with a much larger extent and lower intensities than the pre-flare dimmings. The percentage of the 171 Å intensity decrease reaches 40%. The pre-flare dimmings are most striking in 171, 193, and 211 Å with formation temperatures of 0.6-2.5 MK. The northern part of the pre-flare dimmings could also be recognized in 131 and 335 Å. Conclusions: To our knowledge, this is the first detailed study of pre-flare coronal dimmings; they can be explained by density depletion as a result of the gradual

  3. Sagittal lip positions in different skeletal malocclusions: a cephalometric analysis.

    PubMed

    Joshi, Merina; Wu, Li Peng; Maharjan, Surendra; Regmi, Mukunda Raj

    2015-01-01

    The objectives of this paper are to (1) study use of soft tissue analyses advocated by Steiner, Ricketts, Burstone, Sushner and Holdway to develop soft tissue cephalometric norms as baseline data for sagittal lip position in Northeast Chinese adult population, (2) compare the sagittal lip positions in different skeletal malocclusions and (3) compare the sagittal lip positions in Northeast Chinese adults with other reported populations. Lateral cephalometric radiographs of subjects were taken in natural head position. Radiographs were manually traced and five reference lines - Sushner, Steiner, Burstone, Holdway and Ricketts, were used. The linear distance between the tip of the lips and the five reference lines were measured. Statistical analysis was done using the Statistical Package for Social Sciences (SPSS) 21. Descriptive analysis was done for each variable for each subject. Coefficient of variation between lip positions as assessed by reference lines was determined. Post hoc Tukey's test was used for comparison of the mean cephalometric values of three skeletal malocclusions. The level of significance for the analysis was set at p < 0.05. The findings showed significant difference in the sagittal lip positions in different skeletal malocclusions. There was variation in consistent reference line in each skeletal malocclusion. The S2 line was the most consistent reference line in skeletal class I and class II group. The B line was the most consistent line in skeletal class III. In skeletal class II group, upper lips were the most protrusive and lower lips were retrusive than in skeletal class I and class III groups. In case of skeletal class III group, upper lips were retrusive and lower lips were more protrusive than in skeletal class I and class II groups. The sagittal lip positions were found to be associated with the skeletal malocclusion pattern. Northeast Chinese population has protrusive upper and lower lip in comparison to Caucasians. Each skeletal

  4. Intra- and inter-observer reliability of determining radiographic sagittal parameters of the spine and pelvis using a manual and a computer-assisted methods

    PubMed Central

    Carreon, Leah Y.; Labelle, Hubert; Djurasovic, Mladen; Weidenbaum, Mark; Brown, Courtney; Roussouly, Pierre

    2008-01-01

    Sagittal imbalance is a significant factor in determining clinical treatment outcomes in patients with deformity. Measurement of sagittal alignment using the traditional Cobb technique is frequently hampered by difficulty in visualizing landmarks. This report compares traditional manual measurement techniques to a computer-assisted sagittal plane measurement program which uses a radius arc methodology. The intra and inter-observer reliability of the computer program has been shown to be 0.92–0.99. Twenty-nine lateral 90 cm radiographs were measured by a computer program for an array of sagittal plane measurements. Ten experienced orthopedic spine surgeons manually measured the same parameters twice, at least 48 h apart, using a digital caliper and a standardized radiographic manual. Intraclass correlations were used to determine intra- and interobserver reliability between different manual measures and between manual measures and computer assisted-measures. The inter-observer reliability between manual measures was poor, ranging from −0.02 to 0.64 for the different sagittal measures. The intra-observer reliability in manual measures was better ranging from 0.40 to 0.93. Comparing manual to computer-assisted measures, the ICC ranged from 0.07 to 0.75. Surgeons agreed more often with each other than with the machine when measuring the lumbar curve, the thoracic curve, and the spino-sacral angle. The reliability of the computer program is significantly higher for all measures except for lumbar lordosis. A computer-assisted program produces a reliable measurement of the sagittal profile of the spine by eliminating the need for distinctly visible endplates. The use of a radial arc methodology allows for infinite data points to be used along the spine to determine sagittal measurements. The integration of this technique with digital radiography’s ability to adjust image contrast and brightness will enable the superior identification of key anatomical parameters

  5. Diffraction crystals for sagittally focusing x-rays

    DOEpatents

    Ice, G.E.; Sparks, C.J. Jr.

    1982-06-07

    The invention is a new type of diffraction crystal designed for sagittally focusing photons of various energies. The invention is based on the discovery that such focusing is not obtainable with conventional crystals because of distortion resulting from anticlastic curvature. The new crystal comprises a monocrystalline base having a front face contoured for sagittally focusing photons and a back face provided with rigid, upstanding, stiffening ribs restricting anticlastic curvature. When mounted in a suitable bending device, the reflecting face of the crystal can be adjusted to focus photons having any one of a range of energies.

  6. Sagittal alignment of cervical spine in adult idiopathic scoliosis.

    PubMed

    Aykac, Bilal; Ayhan, Selim; Yuksel, Selcen; Guler, Umit Ozgur; Pellise, Ferran; Alanay, Ahmet; Perez-Grueso, Francisco Javier Sanchez; Acaroglu, Emre

    2015-06-01

    Alignment of the cervical spine (CS) in adolescent idiopathic scoliosis (IS) as well as in asymptomatic adult populations has recently been studied and described as being less lordotic in the adolescent IS population. However, few studies have examined the sagittal alignment of the CS in adult IS or its association with other radiological variables and clinical relevance. The aim of this study is to analyse the sagittal alignment of CS in adult IS and its association with age, alignment of the thoracic, lumbar and global spinal column as well as health-related quality of life (HRQOL) parameters. A retrospective review of prospectively collected data from a multicenter database was performed. Of 468 consecutive adult IS patients, 213 were included in the study; the remainder were excluded due to poor quality X-rays where the CS was not properly visible, or previous surgery. X-rays were measured for the following CS parameters: [Cranial base-C2 (C0-C2) lordosis, C2-C7 lordosis, thoracic (T1) slope, thoracic inlet angle (TIA) and odontoid (Od)-T1 offset using a measurement software]. These measurements were then evaluated for possible associations with patient age and with pre-existing alignment parameters and HRQOL scores using Pearson correlation tests. The average and standard deviations for CS alignment parameters were 32.3° ± 10.2° for C0-C2; 5.7° ± 14.1° for C2-C7; 23.9° ± 11.3° for T1 slope, 70.5° ± 14.7° for TIA and 20.8° ± 16.5° for Od-T1 offset. CS alignment showed a significant (p < 0.05) correlation with age, T kyphosis and several other sagittal alignment parameters such as sagittal vertical axis (SVA), global tilt and T1 sagittal tilt, but not with the HRQOL parameters. The sagittal alignment of the CS in adult IS is less lordotic than the normal average while less kyphotic than that of IS of a younger age. It correlates with age, thoracic kyphosis and some global sagittal alignment parameters. These findings suggest that CS alignment is

  7. The Development of Thoracic Vertebral Sagittal Morphology During Childhood.

    PubMed

    Dede, Ozgur; Büyükdogan, Kadir; Demirkıran, Halil Gökhan; Akpınar, Erhan; Yazıcı, Muharrem

    2016-11-01

    This is a cross-sectional descriptive study objectives to describe normal development of thoracic vertebrae during childhood and document contribution of individual vertebral shape to the sagittal alignment. Sagittal spinal alignment changes during growth. The changes in sagittal alignment during adolescent growth spurt as well as the individual shapes of thoracic vertebrae have been implicated as factors for the development of adolescent idiopathic scoliosis (AIS). The contribution of individual vertebral shape to the sagittal alignment and the changes in the vertebral shape with growth is not known. Sagittal computed tomographic (CT) scans of thoracic vertebrae were examined in children without any evidence of spinal deformity. Vertical distances between the endplates at the most anterior and most posterior sides of vertebral body were measured as anterior vertebral height (aVH) and posterior vertebral height (pVH), respectively. There were a total of 133 CT scans done on 71 male and 62 female children. The children were grouped as follows: Group I (0-2 years of age), Group II (3-6 years of age), Group III (7-9 years of age), Group IV (10-12 years of age), and Group V (13-16 years of age). A-P ratios of vertebral heights were grouped as T1-T5, T6-T8, and T9-T12. Measurements demonstrated that the anterior and posterior heights in each vertebra grew longitudinally and consistently with increasing age. The aVH/pVH ratio of each individual vertebra showed no significant difference according to age. Measurements of thoracic vertebrae on sagittal spinal CT images did not show any differences in the relative growth and heights of the anterior versus posterior walls of the vertebral bodies in any of the segments in any age or age group. The sagittal alignment changes during growth are likely related to maintenance of sagittal balance rather than the shapes of individual vertebrae. Level II. Copyright © 2016 Scoliosis Research Society. Published by Elsevier Inc. All

  8. Diffraction crystal for sagittally focusing x-rays

    DOEpatents

    Ice, Gene E.; Sparks, Jr., Cullie J.

    1984-01-01

    The invention is a new type of diffraction crystal designed for sagittally focusing photons of various energies. The invention is based on the discovery that such focusing is not obtainable with conventional crystals because of distortion resulting from anticlastic curvature. The new crystal comprises a monocrystalline base having a front face contoured for sagittally focusing photons and a back face provided with rigid, upstanding, stiffening ribs restricting anticlastic curvature. When mounted in a suitable bending device, the reflecting face of the crystal can be adjusted to focus photons having any one of a range of energies.

  9. Lower extremity energy absorption and biomechanics during landing, part II: frontal-plane energy analyses and interplanar relationships.

    PubMed

    Norcross, Marc F; Lewek, Michael D; Padua, Darin A; Shultz, Sandra J; Weinhold, Paul S; Blackburn, J Troy

    2013-01-01

    Greater sagittal-plane energy absorption (EA) during the initial impact phase (INI) of landing is consistent with sagittal-plane biomechanics that likely increase anterior cruciate ligament (ACL) loading, but it does not appear to influence frontal-plane biomechanics. We do not know whether frontal-plane INI EA is related to high-risk frontal-plane biomechanics. To compare biomechanics among INI EA groups, determine if women are represented more in the high group, and evaluate interplanar INI EA relationships. Descriptive laboratory study. Research laboratory. Participants included 82 (41 men, 41 women; age = 21.0 ± 2.4 years, height = 1.74 ± 0.10 m, mass = 70.3 ± 16.1 kg) healthy, physically active volunteers. We assessed landing biomechanics with an electromagnetic motion-capture system and force plate. We calculated frontal- and sagittal-plane total, hip, knee, and ankle INI EA. Total frontal-plane INI EA was used to create high, moderate, and low tertiles. Frontal-plane knee and hip kinematics, peak vertical and posterior ground reaction forces, and peak internal knee-varus moment (pKVM) were identified and compared across groups using 1-way analyses of variance. We used a χ (2) analysis to evaluate male and female allocation to INI EA groups. We used simple, bivariate Pearson product moment correlations to assess interplanar INI EA relationships. The high-INI EA group exhibited greater knee valgus at ground contact, hip adduction at pKVM, and peak hip adduction than the low-INI EA group (P < .05) and greater peak knee valgus, pKVM, and knee valgus at pKVM than the moderate- (P < .05) and low- (P < .05) INI EA groups. Women were more likely than men to be in the high-INI EA group (χ(2) = 4.909, P = .03). Sagittal-plane knee and frontal-plane hip INI EA (r = 0.301, P = .006) and sagittal-plane and frontal-plane ankle INI EA were associated (r = 0.224, P = .04). No other interplanar INI EA relationships were found (P > .05). Greater frontal-plane INI EA was

  10. Coroners' records of accidental deaths.

    PubMed Central

    Levene, S

    1991-01-01

    This study set out to provide a description of the children involved in fatal accidents and to ascertain which deaths might have been prevented and by what means. The records from a convenience sample of four coroners (jurisdictions of Inner North London, Birmingham, Bedfordshire, and Ipswich) of inquests opened in 1984-8 on children aged under 15 killed in accidents were reviewed for information on the deceased, the accident, and the injuries sustained. Altogether 225 records (150 boys, 75 girls) were examined. Accidents to pedestrians were the commonest cause of death (81 cases), and road safety engineering measures were the most likely means by which most fatalities might have been prevented. The records frequently omitted information on social circumstances, family structure, ethnic group, or the use of safety equipment. Cooperative coroners can contribute to child safety as their records are rich in information about accidents. This could be made available to parties interested in accident prevention, including community paediatricians. PMID:1953011

  11. Does Tibial Slope Affect Perception of Coronal Alignment on a Standing Anteroposterior Radiograph?

    PubMed

    Schwartz, Adam J; Ravi, Bheeshma; Kransdorf, Mark J; Clarke, Henry D

    2017-07-01

    A standing anteroposterior (AP) radiograph is commonly used to evaluate coronal alignment following total knee arthroplasty (TKA). The impact of coronal alignment on TKA outcomes is controversial, perhaps due to variability in imaging and/or measurement technique. We sought to quantify the effect of image rotation and tibial slope on coronal alignment. Using a standard extramedullary tibial alignment guide, 3 cadaver legs were cut to accept a tibial tray at 0°, 3°, and 7° of slope. A computed tomography scan of the entire tibia was obtained for each specimen to confirm neutral coronal alignment. Images were then obtained at progressive 10° intervals of internal and external rotation up to 40° maximum in each direction. Images were then randomized and 5 blinded TKA surgeons were asked to determine coronal alignment. Continuous data values were transformed to categorical data (neutral [0], valgus [L], and varus [R]). Each 10° interval of external rotation of a 7° sloped tibial cut (or relative internal rotation of a tibial component viewed in the AP plane) resulted in perception of an additional 0.75° of varus. The slope of the proximal tibia bone cut should be taken into account when measuring coronal alignment on a standing AP radiograph. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Interceptive orthopedics for the correction of maxillary transverse and sagittal deficiency in the early mixed dentition period

    PubMed Central

    Talapaneni, Ashok Kumar; Kumar, Karnati Praveen; Kommi, Pradeep Babu; Nuvvula, Sivakumar

    2011-01-01

    Dentofacial Orthopedics directed to a hypoplastic maxilla in the prepubertal period redirects growth of the maxilla in the vertical, transverse and sagittal planes of space. The orthopedic correction of maxillary hypoplasia in the early mixed dentition period thus intercepts the establishment of permanent structural asymmetry in the mandible and helps in the achievement of optimal dentofacial esthetics. This paper presents the growth redirection in a hypoplastic maxilla of an 8-year-old girl with simultaneous rapid maxillary expansion and protraction headgear therapy for a period of 11 months which corrected the posterior unilateral cross-bite, the positional asymmetry of the mandible and established an orthognathic profile in the individual. PMID:22346162

  13. Significance of Coronal Proset Magnetic Resonance Imaging to Detect Hidden Zone of the Mid-Zone Stenosis in the Lumbar Spine and Morphometric Analysis of the Mid-Zone Stenosis

    PubMed Central

    Ahn, Hyo-Sae; Son, Whee Sung; Shin, Ji-Hoon; Ahn, Myun-Whan

    2016-01-01

    Study Design Retrospective exploratory imaging study. Purpose To investigate the significance of the coronal magnetic resonance imaging (MRI) using Proset technique to detect the hidden zone in patients with mid-zone stenosis by comparing with conventional axial and sagittal MRI and to explore the morphologic characteristic patterns of the mid-zone stenosis. Overview of Literature Despite advancements in diagnostic modalities such as computed tomography and MRI, stenotic lesions under the pedicle and pars interarticularis, also called the mid-zone, are still difficult to definitely detect with the conventional axial and sagittal MRI due to its inherited anatomical peculiarity. Methods Of 180 patients scheduled to undergo selective nerve root block, 20 patients with mid-zone stenosis were analyzed using MRI. Characteristic group patterns were also explored morphologically by comparing MRI views of each group after verifying statistical differences between them. Hierarchical cluster analysis was performed to classify morphological characteristic groups based on three-dimensional radiologic grade for stenosis at all three zones. Results At the mid-zone, the stenosis of grade 2 or more was found in 14 cases in the coronal image,13 cases in the sagittal image, and 9 cases in the axial image (p<0.05). Especially, mid-zone stenosis was not detected in six of 20 cases at the axial images. At the entrance and exit-zone, coronal image was also associated with more accurate detection of hidden zone compared to other views such as axial and sagittal images. After repeated statistical verification, the morphological patterns of hidden zone were classified into 5 groups: 6 cases in group I; 1 case in group II; 4 cases in group III; 7 cases in group IV; and 2 cases in group V. Conclusions Coronal MRI using the Proset technique more accurately detected hidden zone of the mid-zone stenosis compared to conventional axial and sagittal images. PMID:27559443

  14. Radio Studies of Coronal Holes.

    DTIC Science & Technology

    1981-03-01

    Maps Solar Wind Streams Radio Spectra Interplanetary Scintillation 20. A9 RACY (Continue an reveree side If necesary end Identify by block number...summarizes our efforts to identify individual high latitudecoronal holes with high speed solar wind streams far above or below the ecliptic,/The coronal...holes were identified from the Kitt Peak 10830 1 synoptic maps, while the high speed solar wind streams were identified from the interplanetary

  15. Three-dimensional kinetic analysis of running: significance of secondary planes of motion.

    PubMed

    McClay, I; Manal, K

    1999-11-01

    The study of angular kinetic data provides important information regarding muscle function and may lend insight into the etiology of overuse injuries common to runners. These injuries are often due to deviations in the secondary planes of motion. However, little is known about the angular kinetics in these planes leaving no reference for comparison. Therefore, three-dimensional kinematic and ground reaction force data were collected on 20 recreational runners with normal rearfoot mechanics. Findings suggest that sagittal plane kinetic data were similar to the two-dimensional studies reported in the literature. Sagittal plane data were least variable (CV: 9.3-11.0%) and comprised the largest percentage of positive or negative work done (80.2-88.8%) at both the rearfoot and knee joints. Transverse plane kinetics were most variable (CV: 68.5-151.9%) and constituted the smallest percentage of work done at both joints (0.7-7.4%). Although relatively smaller than the sagittal plane component, a substantial amount of positive work was done in the frontal plane at both joints (16.1-18.9%), suggesting that this component should not be ignored.

  16. Impulsively generated fast coronal pulsations

    NASA Technical Reports Server (NTRS)

    Edwin, P. M.; Roberts, B.

    1986-01-01

    Rapid oscillations in the corona are discussed from a theoretical standpoint, developing some previous work on ducted, fast magnetoacoustic waves in an inhomogeneous medium. In the theory, impulsively (e.g., flare) generated mhd (magnetohydrodynamic) waves are ducted by regions of low Alfven speed (high density) such as coronal loops. Wave propagation in such ducts is strongly dispersive and closely akin to the behavior of Love waves in seismology, Pekeris waves in oceanography and guided waves in fiber optics. Such flare-generated magnetoacoustic waves possess distinctive temporal signatures consisting of periodic, quasi-periodic and decay phases. The quasi-periodic phase possesses the strongest amplitudes and the shortest time scales. Time scales are typically of the order of a second for inhomogeneities (coronal loop width) of 1000 km and Alfven speeds of 1000/kms, and pulse duration times are of tens of seconds. Quasi-periodic signatures have been observed in radio wavelengths for over a decade and more recently by SMM. It is hoped that the theoretical ideas outlined may be successfully related to these observations and thus aid the interpretation of oscillatory signatures recorded by SMM. Such signatures may also provide a diagnostic of coronal conditions. New aspects of the ducted mhd waves, for example their behavior in smoothly varying as opposed to tube-like inhomogeneities, are currently under investigation. The theory is not restricted to loops but applied equally to open field regions.

  17. Polarization of Coronal Forbidden Lines

    NASA Astrophysics Data System (ADS)

    Li, Hao; Landi Degl'Innocenti, Egidio; Qu, Zhongquan

    2017-03-01

    Since the magnetic field is responsible for most manifestations of solar activity, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields, particularly in the outer atmosphere. To this end, it is important to develop rigorous diagnostic tools to interpret polarimetric observations in suitable spectral lines. This paper is devoted to analyzing the diagnostic content of linear polarization imaging observations in coronal forbidden lines. Although this technique is restricted to off-limb observations, it represents a significant tool to diagnose the magnetic field structure in the solar corona, where the magnetic field is intrinsically weak and still poorly known. We adopt the quantum theory of polarized line formation developed in the framework of the density matrix formalism, and synthesize images of the emergent linear polarization signal in coronal forbidden lines using potential-field source-surface magnetic field models. The influence of electronic collisions, active regions, and Thomson scattering on the linear polarization of coronal forbidden lines is also examined. It is found that active regions and Thomson scattering are capable of conspicuously influencing the orientation of the linear polarization. These effects have to be carefully taken into account to increase the accuracy of the field diagnostics. We also found that linear polarization observation in suitable lines can give valuable information on the long-term evolution of the magnetic field in the solar corona.

  18. THE CORONAL LOOP INVENTORY PROJECT

    SciTech Connect

    Schmelz, J. T.; Pathak, S.; Christian, G. M.; Dhaliwal, R. S. S.; Paul, K. S.

    2015-11-01

    Most coronal physicists now seem to agree that loops are composed of tangled magnetic strands and have both isothermal and multithermal cross-field temperature distributions. As yet, however, there is no information on the relative importance of each of these categories, and we do not know how common one is with respect to the other. In this paper, we investigate these temperature properties for all loop segments visible in the 171-Å image of AR 11294, which was observed by the Atmospheric Imaging Assembly (AIA) on 2011 September 15. Our analysis revealed 19 loop segments, but only 2 of these were clearly isothermal. Six additional segments were effectively isothermal, that is, the plasma emission to which AIA is sensitive could not be distinguished from isothermal emission, within measurement uncertainties. One loop had both isothermal transition region and multithermal coronal solutions. Another five loop segments require multithermal plasma to reproduce the AIA observations. The five remaining loop segments could not be separated reliably from the background in the crucial non-171-Å AIA images required for temperature analysis. We hope that the direction of coronal heating models and the efforts modelers spend on various heating scenarios will be influenced by these results.

  19. Coronal Loops: Isothermal or Multithermal?

    NASA Astrophysics Data System (ADS)

    Kimble, Jason; Schmelz, J. T.; Nasraoui, K.; Cirtain, J. W.; Del Zanna, G.; DeLuca, E. E.; Mason, H. E.

    2007-05-01

    The coronal loop data used for this analysis were taken on 2003 January 17 at 14:24:45 UT by the Coronal Diagnostic Spectrometer (CDS) aboard the Solar and Heliospheric Observatory. We use the Chianti atomic physics data base and the hybrid coronal abundances to determine temperatures and densities for positions along several loops. The traditional method used to create our differential emission measure (DEM) curves has been forward folding, but we are now using both emission measure loci plots and DEM automatic inversion to support and confirm the original conclusions. In this poster, we will look specifically at the emission measure loci analysis of three loops visible in the CDS data set. We find different results for each of these loops. One of the loops seems to be composed of isothermal plasma with Log T = 5.8 MK. The temperature does not appear to change with position, from the footpoint to the loop leg. Unfortunately, the loop top is outside the CDS field of view. Each pixel examined in the second loop seems to require a multithermal DEM distribution. For the third loop, the temperature increases and the density appears to decrease with loop height, reminiscent of traditional hydrostatic loop models. Solar physics research at the University of Memphis is supported by NSF ATM-0402729 and NASA NNG05GE68G.

  20. The Structure of Coronal Loops

    NASA Technical Reports Server (NTRS)

    Antiochos, Spiro K.

    2009-01-01

    It is widely believed that the simple coronal loops observed by XUV imagers, such as EIT, TRACE, or XRT, actually have a complex internal structure consisting of many (perhaps hundreds) of unresolved, interwoven "strands". According to the nanoflare model, photospheric motions tangle the strands, causing them to reconnect and release the energy required to produce the observed loop plasma. Although the strands, themselves, are unresolved by present-generation imagers, there is compelling evidence for their existence and for the nanoflare model from analysis of loop intensities and temporal evolution. A problem with this scenario is that, although reconnection can eliminate some of the strand tangles, it cannot destroy helicity, which should eventually build up to observable scales. we consider, therefore, the injection and evolution of helicity by the nanoflare process and its implications for the observed structure of loops and the large-scale corona. we argue that helicity does survive and build up to observable levels, but on spatial and temporal scales larger than those of coronal loops. we discuss the implications of these results for coronal loops and the corona, in general .

  1. Speeds and accelerations of coronal mass ejections

    NASA Technical Reports Server (NTRS)

    St.cyr, O. Chris; Hundhausen, A. J.; Burkepile, J. T.

    1992-01-01

    More than 1300 coronal mass ejections have been detected in observations made by the coronagraph aboard SMM during 1980 and 1984-1989. The speed (projected onto the plane of the sky) for at least one morphoplogical feature in about half of these mass ejections could be measured. The average speed of all mass ejection features was about 350 km/s, but speeds range from a few 10s of km/s to more than 2000 km/s. There also appear to be significant variations between the speed distributions for different years. When a mass ejection feature appeared in three or more sequential images, its acceleration could also be calculated. But, because of the limited time a mass ejection remained in the SMM field of view, the ability to detect any given acceleration diminished with increasing mass ejection speed. In fact, the SMM observations do not reveal a discernable acceleration for most mass ejections. A modest yet credible acceleration was detected in 136 cases, while a deceleration was detected in only 7 cases. The LASCO coronagraph will have a more extensive field of view than the SMM instrument; hence, with these new SOHO (Solar and Heliospheric Observatory) observations, some of the challenging questions concerning mass ejection dynamics can be addressed. How far away from the Sun does the material in a mass ejection continue being accelerated? At what radial distance is the motion of the mass ejection dominated by deceleration as it interacts with the ambient interplanetary material?

  2. Two-plane symmetry in the structural organization of man.

    PubMed

    Ermolenko, A E

    2005-01-01

    Manifestations of symmetry in the human structural organization in ontogenesis and phylogenetic development are analysed. A concept of macrobiocrystalloid with inherent complex symmetry is proposed for the description of the human organism in its integrity. The symmetry can be characterized as two-plane radial (quadrilateral), where the planar symmetry is predominant while the layout of organs of radial symmetry is subordinated to it. Out of the two planes of symmetry (sagittal and horizontal), the sagittal plane is predominant: (a) the location of the organs is governed by two principles: in compliance with the symmetry planes and in compliance with the radial symmetry around cavities; (b) the location of the radial symmetry organs is also governed by the principle of two-plane symmetry; (c) out of the four antimeres of two-plane symmetry, two are paired while the other two have merged into one organ; (d) some organs which are antimeres relative to the horizontal plane are located at the cranial end of the organism (sensory organs, cerebrum-cerebellum, heart-spleen and others). The two-plane symmetry is formed by two mechanisms--(a) the impact of morphogenetic fields of the whole crystalloid organism during embriogenesis and (b) genetic mechanisms of the development of chromosomes having two-plane symmetry. When comparing mineral and biological entities we should consider not the whole immobile crystal but only the active superficial part of a growing or dissolving crystal, the interface between the crystal surface and the crystal-forming environment which directly controls crystal growth and adapts itself to it, as well as crystal feed stock expressed in the structure of concentration flows. The symmetry of the chromosome, of the embrion at the early stages of cell cleavage as well as of some organs and systems in their phylogenetic development is described.

  3. On the nature of transverse coronal waves revealed by wavefront dislocations

    NASA Astrophysics Data System (ADS)

    López Ariste, A.; Luna, M.; Arregui, I.; Khomenko, E.; Collados, M.

    2015-07-01

    Context. Coronal waves are an important aspect of the dynamics of the plasma in the corona. Wavefront dislocations are topological features of most waves in nature and also of magnetohydrodynamic waves. Are there dislocations in coronal waves? Aims: The finding and explanation of dislocations may shed light on the nature and characteristics of the propagating waves, their interaction in the corona, and in general on the plasma dynamics. Methods: We positively identify dislocations in coronal waves observed by the Coronal Multi-channel Polarimeter (CoMP) as singularities in the Doppler shifts of emission coronal lines. We study the possible singularities that can be expected in coronal waves and try to reproduce the observed dislocations in terms of localization and frequency of appearance. Results: The observed dislocations can only be explained by the interference of a kink and sausage wave modes propagating with different frequencies along the coronal magnetic field. In the plane transverse to the propagation, the cross-section of the oscillating plasma must be smaller than the spatial resolution, and the two waves result in net longitudinal and transverse velocity components that are mixed through projection onto the line of sight. Alfvén waves can be responsible for the kink mode, but a magnetoacoustic sausage mode is necessary in all cases. Higher (flute) modes are excluded. The kink mode has a pressure amplitude that is less than the pressure amplitude of the sausage mode, though its observed velocity is higher. This concentrates dislocations on the top of the loop. Conclusions: To explain dislocations, any model of coronal waves must include the simultaneous propagation and interference of kink and sausage wave modes of comparable but different frequencies with a sausage wave amplitude much smaller than the kink one. Appendix A is available in electronic form at http://www.aanda.org

  4. Gravitational forces and sagittal shape of the spine

    PubMed Central

    Duval-Beaupere, G.

    2007-01-01

    The sagittal morphology of the pelvis determines the amount of lordosis needed for each individual. The proper harmony of the sagittal spinal curves allows a stable balance, economical in terms of mechanical effects and muscular energy. A previous barycentremetrical laboratory study allowed us to demonstrate that the axis of gravity of the upper body segment was located behind the lumbar vertebrae and the femoral heads, thus ensuring economy and stability. The determination of the anatomical connection of the individual gravity is thus of primary importance for the evaluation of sagittal balance. Data for 42 patients without spinal pathology, previously evaluated by barycentremetry, were used to establish a predictive equation for the application point of the gravity at the level of the third lumbar vertebra (L3). This equation, using anthropometric and radiographic pelvic and spinal parameters, was integrated into a software program called Similibary. It was applied to the same 42 subjects. These results were compared in order to validate the method. No significant difference was observed between the two techniques. This easy-to-use tool allows a personalised evaluation of the sagittal balance of the spine, both through the evaluation of the harmonious relationship between the spinal curves and the pelvis, and through the location of gravity supported by the vertebral structures in L3. PMID:17653545

  5. The effect of growing rod lengthening technique on the sagittal spinal and the spinopelvic parameters.

    PubMed

    Atici, Yunus; Akman, Yunus Emre; Erdogan, Sinan; Sari, Seçkin; Yavuz, Umut; Carkci, Engin; Kaygusuz, Mehmet Akif

    2015-06-01

    The aim of this retrospective clinical study is to evaluate the effect of growing rod lengthening technique on sagittal balance in relationship with the spinopelvic parameters, in early onset scoliosis (EOS). Twenty-three patients (18 female, 5 male), with a mean age of 8.3 years during the operation (range 3.2-12.2), with EOS due to various etiologies were operated using growing rod (8 single, 15 dual) technique, between the years 2007 and 2011. The patients were operated in two different institutions and were evaluated retrospectively via the parameters on the radiographic charts including the mean curve angle, T1-S1 distance, cervical lordosis, thoracic kyphosis, lumbar lordosis, sagittal and coronal balance, pelvic tilt, sacral slope and pelvic incidence. The parameters were measured in the preoperative and the early postoperative periods and during the last follow-up. The data obtained from the measurements were evaluated statistically. Complications were also noted. The mean follow-up period was 34.2 months (range 24-57.6). The mean thoracic kyphosis angle was 53.6° (range 25°-119°) preoperatively, 39.6° (range 20°-61°) early postoperatively (p < 0.05) and 39.9° (range 21°-65°) during the last follow-up (p < 0.05). The mean lumbar lordosis angle was -46.1° (range -67° to -13°) preoperatively, -41° (range -64° to -11°) early postoperatively (p > 0.05) and -39.7° (range -62° to -16°) during the last follow-up (p > 0.05). Average sagittal balance was measured as 0.2 cm (range -7 to 24.7 cm) preoperatively, -0.1 cm (range -6.6 to 8.5 cm) initial postoperatively (p > 0.05) and -0.2 cm (range -7.3 to 13.5 cm) during the last follow-up (p > 0.05). The average pelvic incidence was found as 46.4° (range 27°-83°) preoperatively, 45.2° (range 28°-78°) (p > 0.05) early postoperatively and 45.7° (range 28°-82°) during the last follow-up (p > 0.05). We have encountered complications in 14 patients. These consisted of eight rod fractures, seven

  6. Sagittal parameters of global cervical balance using EOS imaging: normative values from a prospective cohort of asymptomatic volunteers.

    PubMed

    Le Huec, J C; Demezon, H; Aunoble, S

    2015-01-01

    To define reference parameters for analyzing sagittal balance of the cervical spine in asymptomatic volunteers. Prospective study after Bioethics Committee approval. Imaging performed using a low-dose radiographic system (EOS Imaging, Paris, France). The absence of pain was assessed using the Oswestry Questionnaire and VAS. 106 subjects were included of whom 55.66 % were men. The parameters measured were: pelvic incidence, pelvic tilt, sacral slope, thoracic and lumbar curvature, C7 plumb line position and the spino-sacral angle. The C7 slope and new parameters were measured: cranial incidence, defined in relation to the McGregor line and the sella turcica allowing to define cranial slope and tilt, and the spino-cranial angle (SCA). This study demonstrated a close correlation between the C7 slope and the cranio-cervical system. Economic sagittal balance in the asymptomatic population was defined by a constant SCA angle of 83° ± 9°. To maintain this balance, a spine with a marked C7 slope will present lordosis and vice versa. Cranial incidence is an anatomical parameter characteristic of the cranio-cervical system which makes it possible to analyze the spatial positioning of the head and to predict the desired value of cervical lordosis which is closely correlated to cranial slope. The C7 slope has a predictive value of the shape of the cervical spine in the sagittal plane. One-third of the asymptomatic population had cervical kyphosis. Our results could be used to study sagittal balance before and after arthrodesis, or cervical prosthesis.

  7. Finite element analysis of head-neck kinematics during motor vehicle accidents: analysis in multiple planes.

    PubMed

    Teo, Ee Chon; Zhang, Qing Hang; Huang, Russel C

    2007-01-01

    In this study, a detailed three-dimensional head-neck (C0-C7) finite element (FE) model developed previously based on the actual geometry of a human cadaver specimen was used. Five simulation analyses were performed to investigate the kinematic responses of the head-neck complex under rear-end, front, side, rear- and front-side impacts. Under rear-end and front impacts, it was predicted that the global and intervertebral rotations of the head-neck in the sagittal plane displayed nearly symmetric curvatures about the frontal plane. The primary sagittal rotational angles of the neck under direct front and rear-end impact conditions were higher than the primary frontal rotational angles under other side impact conditions. The analysis predicted early S-shaped and subsequent C-shaped curvatures of the head-neck complex in the sagittal plane under front and rear-end impact, and in the frontal plane under side impact. The head-neck complex flexed laterally in one direction with peak magnitude of larger than 22 degrees and a duration of about 130 ms before flexing in the opposite direction under both side and rear-side impact, compared to the corresponding values of about 15 degrees and 105 ms under front-side impact. The C0-C7 FE model has reasonably predicted the effects of impact direction in the primary sagittal and frontal segmental motion and curvatures of the head-neck complex under various impact conditions.

  8. Coronal abundances determined from energetic particles

    NASA Technical Reports Server (NTRS)

    Reames, D. V.

    1995-01-01

    Solar energetic particles (SEPs) provide a measurement of coronal element abundances that is highly independent of the ionization states and temperature of the ions in the source plasma. The most complete measurements come from large 'gradual' events where ambient coronal plasma is swept up by the expanding shock wave from a coronal mass ejection. Particles from 'impulsive' flares have a pattern of acceleration-induced enhancements superimposed on the coronal abundances. Particles accelerated from high-speed solar wind streams at corotating shocks show a different abundance pattern corresponding to material from coronal holes. Large variations in He/O in coronal material are seen for both gradual and impulsive-flare events but other abundance ratios, such as Mg/Ne, are remarkably constant. SEP measurements now include hundreds of events spanning 15 years of high-quality measurement.

  9. Some Considerations about Inferring Coronal Magnetic Fields and Other Coronal Properties from Coronal Emission Line Polarization

    NASA Astrophysics Data System (ADS)

    Arnaud, J.; Habbal, S. R.; Arndt, M.; Woo, R.

    2003-12-01

    Ground based studies of Coronal Emission Lines (CEL) linear polarization had been carried out for the 530.3 nm FeXIV line at Pic du Midi and for the 1074.7 nm Fe XIII line at Sac Peak in the 1977-1980 period. The large scale organization of the polarization has clearly revealed the existence of a large scale structure of the coronal magnetic field. More recently, the first successful eclipse CEL polarimetric measurements were made in the 1074.7 nm line during the total solar eclipse of 21 June 2001, confirming earlier results of the predominance of a radial direction of the coronal magnetic field. A first measurement of the circular polarization in the 1074.7 nm line has also recently been performed. Circular polarization gives access to the strength of the LOS magnetic field while the linear polarization maps the transverse magnetic field direction. We will use ground based and eclipse 1074.7 nm line polarimetric data to provide examples of the properties (e.g., magnetic field, abundances, inhomogeneities) such observations can help to infer in this 3-D and optically thin medium.

  10. A SOLAR CORONAL JET EVENT TRIGGERS A CORONAL MASS EJECTION

    SciTech Connect

    Liu, Jiajia; Wang, Yuming; Shen, Chenglong; Liu, Kai; Pan, Zonghao; Wang, S.

    2015-11-10

    In this paper, we present multi-point, multi-wavelength observations and analysis of a solar coronal jet and coronal mass ejection (CME) event. Employing the GCS model, we obtained the real (three-dimensional) heliocentric distance and direction of the CME and found it to propagate at a high speed of over 1000 km s{sup −1}. The jet erupted before the CME and shared the same source region. The temporal and spacial relationship between these two events lead us to the possibility that the jet triggered the CME and became its core. This scenario hold the promise of enriching our understanding of the triggering mechanism of CMEs and their relations to coronal large-scale jets. On the other hand, the magnetic field configuration of the source region observed by the Solar Dynamics Observatory (SDO)/HMI instrument along with the off-limb inverse Y-shaped configuration observed by SDO/AIA in the 171 Å passband provide the first detailed observation of the three-dimensional reconnection process of a large-scale jet as simulated in Pariat et al. The eruption process of the jet highlights the importance of filament-like material during the eruption of not only small-scale X-ray jets, but likely also of large-scale EUV jets. Based on our observations and analysis, we propose the most probable mechanism for the whole event, with a blob structure overlaying the three-dimensional structure of the jet, to describe the interaction between the jet and the CME.

  11. EUV Coronal Dimming and its Relationship to Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Mason, James

    2016-05-01

    As a coronal mass ejection (CME) departs from the inner solar atmosphere, it leaves behind a void. This region of depleted plasma results in a corresponding decrease in coronal emissions that can be observed by instruments tuned to measure the extreme ultraviolet (EUV) part of the electromagnetic spectrum. These coronal dimmings can be observed with EUV imagers and EUV spectral irradiance instruments. Onboard the Solar Dynamics Observatory (SDO), the EUV Variability Experiment (EVE) and Atmospheric Imaging Assembly (AIA) provide complementary observations; together they can be used to obtain high spatial and spectral resolution. AIA provides information about the location, extent, and spatial evolution of the dimming while EVE data are important to understand plasma temperature evolution. Concurrent processes with similar timescales to mass-loss dimming also impact the observations, which makes a deconvolution method necessary for the irradiance time series in order to have a “clean” mass-loss dimming light curve that can be parameterized and compared with CME kinematics. This presentation will first provide background on these various physical processes and the deconvolution method developed. Two case studies will then be presented, followed by a semi-statistical study (~30 events) to establish a correlation between dimming and CME parameters. In particular, the slope of the deconvolved irradiance dimming light curve is representative of the CME speed, and the irradiance dimming depth can serve as a proxy for CME mass. Finally, plans and early results from a more complete statistical study of all dimmings in the SDO era, based on an automated detection routine using EVE data, will be described and compared with independently derived dimmings automatically detected with AIA data.

  12. Influence of metopic suture fusion associated with sagittal synostosis.

    PubMed

    Domeshek, Leahthan F; Das, Rajesh R; Van Aalst, John A; Mukundan, Srinivasan; Marcus, Jeffrey R

    2011-01-01

    Some patients with sagittal synostosis present with a fused metopic suture. We hypothesize that premature metopic suture fusion consistently and identifiably alters form associated with sagittal synostosis. We previously validated three-dimensional vector analysis as a tool for the study of cranial morphology and used it herein to distinguish between dysmorphologies of isolated sagittal synostosis (ISS) and combined sagittal-metopic synostosis (CSM). Preoperative computed tomographic scans for patients with ISS and CSM were compared with matched normative counterparts. Premature metopic suture fusion was defined by established radiographic criteria. Color-coded point clouds were created for each scan, with color gradient based on patient deviation from normal across the dysmorphic skull. Standard deviation data were evaluated in 7 cranial regions and compared between ISS and CSM. Mean ISS and CSM point clouds were evaluated. Using three-dimensional vector analysis, standard anthropometric data/indices were determined and compared between the 2 groups. Differences in ISS and CSM regional deviations and index measurements were not statistically significant. Mean ISS and CSM representations depicted similar overall morphology. Using accepted criteria for identification of metopic synostosis in CSM, only subtle differences appear between the 2 populations on average. Expected morphologic changes associated with metopic synostosis are present in only a small number of patients with CSM, arguing against our hypothesis, and calling into question the criteria used to identify premature metopic suture fusion. Normal metopic suture fusion occurs for a continuum of time. Our findings suggest that the normal continuum may begin earlier than the literature suggests. In the setting of sagittal synostosis, the influence of metopic suture fusion and treatment is best determined by individual morphologic analysis.

  13. The relationship between coronal streamers and CMEs.

    NASA Astrophysics Data System (ADS)

    Du, Jinsheng; Tong, Yi; Yang, Jing; Eselevich, V. G.

    1999-06-01

    The variation of the polarization brightness of coronal streamer in Carrington Rotations 1591 - 1592 is investigated. The distribution of the polarization brightness along streamer belts is inhomogeneous; the degree of the inhomogeneity is 10% - 50%. In the absence of coronal mass ejection (CME) influence, the distribution of coronal streamers along the streamer belts can persist stable during nearly two Carrington Rotations. The rise velocity of the top of the cusp region in a coronal streamer may be more than 2 km/s, if the longitude angular size is more than 27° associated with a CME occurrence.

  14. Retrograde lag screw placement in anterior acetabular column with regard to the anterior pelvic plane and midsagittal plane -- virtual mapping of 260 three-dimensional hemipelvises for quantitative anatomic analysis.

    PubMed

    Ochs, Bjoern Gunnar; Stuby, Fabian Maria; Ateschrang, Atesch; Stoeckle, Ulrich; Gonser, Christoph Emanuel

    2014-10-01

    Percutaneous screw placement can be used for minimally invasive treatment of none or minimally displaced fractures of the anterior column. The complex pelvic geometry can pose a major challenge even for experienced surgeons. The present study examined the preformed bone stock of the anterior column in 260 hemipelvises (130 male and 130 female). Screws were virtually implanted using iPlan(®) CMF (BrainLAB AG, Feldkirchen, Germany); the maximal implant length and the maximal implant diameter were assessed. The study showed, that 6.5mm can generally be used in men; in women however individual planning is essential in regard to the maximal implant diameter since we found that in 15.4% of women, screws with a diameter less than 6.5mm were necessary. The virtual analysis of the preformed bone stock corridor of the anterior column showed two constrictions of crucial clinical importance. These can be found after 18% and 55% (men) respectively 16% and 55% (women) measured from the entry point along the axis of the implant. The entry point of the retrograde anterior column screw in our collective was located lateral of tuberculum pubicum at the level of the superior-medial margin of foramen obturatum. In female patients, the entry point was located significantly more lateral of symphysis and closer to the cranial margin of ramus superior ossis pubis. The mean angle between the screw trajectory and the anterior pelvic plane in sagittal section was 31.6 ± 5.5°, the mean angle between the screw trajectory and the midsagittal plane in axial section was 55.9 ± 4.6° and the mean angle between the screw trajectory and the midsagittal plane in coronal section was 42.1 ± 3.9° with no significant deviation between both sexes. The individual angles formed by the screw trajectory and the anterior pelvic and midsagittal plane are independent from anthropometric parameters sex, age, body length and weight. Therefore, they can be used for orientation in lag screw placement keeping

  15. Super-resolution reconstruction in frequency, image, and wavelet domains to reduce through-plane partial voluming in MRI

    SciTech Connect

    Gholipour, Ali Afacan, Onur; Scherrer, Benoit; Prabhu, Sanjay P.; Warfield, Simon K.; Aganj, Iman; Sahin, Mustafa

    2015-12-15

    Purpose: To compare and evaluate the use of super-resolution reconstruction (SRR), in frequency, image, and wavelet domains, to reduce through-plane partial voluming effects in magnetic resonance imaging. Methods: The reconstruction of an isotropic high-resolution image from multiple thick-slice scans has been investigated through techniques in frequency, image, and wavelet domains. Experiments were carried out with thick-slice T2-weighted fast spin echo sequence on the Academic College of Radiology MRI phantom, where the reconstructed images were compared to a reference high-resolution scan using peak signal-to-noise ratio (PSNR), structural similarity image metric (SSIM), mutual information (MI), and the mean absolute error (MAE) of image intensity profiles. The application of super-resolution reconstruction was then examined in retrospective processing of clinical neuroimages of ten pediatric patients with tuberous sclerosis complex (TSC) to reduce through-plane partial voluming for improved 3D delineation and visualization of thin radial bands of white matter abnormalities. Results: Quantitative evaluation results show improvements in all evaluation metrics through super-resolution reconstruction in the frequency, image, and wavelet domains, with the highest values obtained from SRR in the image domain. The metric values for image-domain SRR versus the original axial, coronal, and sagittal images were PSNR = 32.26 vs 32.22, 32.16, 30.65; SSIM = 0.931 vs 0.922, 0.924, 0.918; MI = 0.871 vs 0.842, 0.844, 0.831; and MAE = 5.38 vs 7.34, 7.06, 6.19. All similarity metrics showed high correlations with expert ranking of image resolution with MI showing the highest correlation at 0.943. Qualitative assessment of the neuroimages of ten TSC patients through in-plane and out-of-plane visualization of structures showed the extent of partial voluming effect in a real clinical scenario and its reduction using SRR. Blinded expert evaluation of image resolution in

  16. Super-resolution reconstruction in frequency, image, and wavelet domains to reduce through-plane partial voluming in MRI

    PubMed Central

    Gholipour, Ali; Afacan, Onur; Aganj, Iman; Scherrer, Benoit; Prabhu, Sanjay P.; Sahin, Mustafa; Warfield, Simon K.

    2015-01-01

    Purpose: To compare and evaluate the use of super-resolution reconstruction (SRR), in frequency, image, and wavelet domains, to reduce through-plane partial voluming effects in magnetic resonance imaging. Methods: The reconstruction of an isotropic high-resolution image from multiple thick-slice scans has been investigated through techniques in frequency, image, and wavelet domains. Experiments were carried out with thick-slice T2-weighted fast spin echo sequence on the Academic College of Radiology MRI phantom, where the reconstructed images were compared to a reference high-resolution scan using peak signal-to-noise ratio (PSNR), structural similarity image metric (SSIM), mutual information (MI), and the mean absolute error (MAE) of image intensity profiles. The application of super-resolution reconstruction was then examined in retrospective processing of clinical neuroimages of ten pediatric patients with tuberous sclerosis complex (TSC) to reduce through-plane partial voluming for improved 3D delineation and visualization of thin radial bands of white matter abnormalities. Results: Quantitative evaluation results show improvements in all evaluation metrics through super-resolution reconstruction in the frequency, image, and wavelet domains, with the highest values obtained from SRR in the image domain. The metric values for image-domain SRR versus the original axial, coronal, and sagittal images were PSNR = 32.26 vs 32.22, 32.16, 30.65; SSIM = 0.931 vs 0.922, 0.924, 0.918; MI = 0.871 vs 0.842, 0.844, 0.831; and MAE = 5.38 vs 7.34, 7.06, 6.19. All similarity metrics showed high correlations with expert ranking of image resolution with MI showing the highest correlation at 0.943. Qualitative assessment of the neuroimages of ten TSC patients through in-plane and out-of-plane visualization of structures showed the extent of partial voluming effect in a real clinical scenario and its reduction using SRR. Blinded expert evaluation of image resolution in

  17. Stability of solar coronal loops

    NASA Astrophysics Data System (ADS)

    Goedbloed, J. P.

    1990-05-01

    The equations of magnetohydrodynamics do not contain an intrinsic length scale determining the size of phenomena. Hence, size only enters through the external geometrical properties of the configurations considered. This is one of the reasons why tokamaks and solar coronal loops may be considered as similar objects. The equations of MHD do not distinguish between the two. It is only the geometry and, hence, the boundary conditions that discriminate between them. Whereas for tokamaks toroidal periodicity and normal confinement provide the appropriate boundary conditions, for coronal loops line-tying at the photosphere and some prescription for the behavior across the ``edge'' of the loop determine the solutions. The latter is a more complicated problem and gives rise to even more complex dynamics than encountered in tokamaks. Here, we consider the influence of the two mentioned groups of boundary conditions for the problem of the stability and disruption of a solar coronal loop. We consider the stability properties of a single loop with twisted magnetic field lines under the simultaneous influence of photospheric line-tying and constraining by neighboring flux loops. The loops would be violently unstable without these two ingredients (i.e. for the corresponding tokamak problem). It is shown that line-tying alone in not sufficient for stability, but the neighboring flux tubes provide a normal boundary condition similar to a conducting shell in tokamaks. This stabilization gets lost on the time scale associated with reconnection of the tangetial magnetic field discontinuities present in the many-loop system. On this time scale the magnetic energy, which has been built up during the twisting of the field lines, gets released, resulting in a disruption of the loop. This process may be considered as the single loop variant of Parker's solar flare model.

  18. On Recurrent/Homologous Coronal Jets Emission: Coronal Geyser Structures

    NASA Astrophysics Data System (ADS)

    Razvan Paraschiv, Alin; Donea, Alina

    2016-05-01

    Active region 11302 has shown a vast display of solar jets during its lifetime. We examine the emission mechanism responsible for multiple coronal jet events occurring at the center-east side of the active region. Identified jet events were detected in extreme-ultraviolet (EUV), hard X-ray (HXR) and radio emissions, observed by dedicated instruments such as SDO's AIA and HMI, STEREO's EUVI and WAVES, and RHESSI, respectively. We report the detection of a base-arch structure in the lower atmosphere. The site was labelled "Coronal Geyser". The structure had emitted jets quasi-periodically for the entire time the AR was visible in SDO'S field of view. The jets expand into the corona with an apparent line of sight velocity of ~200-300$ km/s. To our knowledge the long time-scale behaviour of jet recurrence and base geyser structure was not previously discussed and data analysis of this phenomena will provide new information for theoretical modelling and data interpretation of jets.

  19. Using Strong Solar Coronal Emission Lines as Coronal Flux Proxies

    NASA Technical Reports Server (NTRS)

    Falconer, David A.; Jordan, Studart D.; Davila, Joseph M.; Thomas, Roger J.; Andretta, Vincenzo; Brosius, Jeffrey W.; Hara, Hirosha

    1997-01-01

    A comparison of Skylab results with observations of the strong EUV lines of Fe XVI at 335 A and 361 A from the Goddard Solar EUV Rocket Telescope and Spectrograph (SERTS) flight of 1989 suggests that these lines, and perhaps others observed with SERTS, might offer good proxies for estimating the total coronal flux over important wavelength ranges. In this paper, we compare SERTS observations from a later, 1993 flight with simultaneous cospatial Yohkoh soft X-ray observations to test this suggestion over the energy range of the Soft X-ray Telescope (SXT) on Yohkoh. Both polynomial and power-law fits are obtained, and errors are estimated, for the SERTS lines of Fe XVI 335 A and 361 A, Fe XV 284 A and 417 A, and Mg IX 368 A. It is found that the power-law fits best cover the full range of solar conditions from quiet Sun through active region, though not surprisingly the 'cooler' Mg IX 368 A line proves to be a poor proxy. The quadratic polynomial fits yield fair agreement over a large range for all but the Mg IX line, but the linear fits fail conspicuously when extrapolated into the quiet Sun regime. The implications of this work for the He 11 304 A line formation problem are briefly considered. The paper concludes with a discussion of the value of these iron lines observed with SERTS for estimating stellar coronal fluxes, as observed for example with the EUVE satellite.

  20. Using Strong Solar Coronal Emission Lines as Coronal Flux Proxies

    NASA Technical Reports Server (NTRS)

    Falconer, David A.; Jordan, Studart D.; Davila, Joseph M.; Thomas, Roger J.; Andretta, Vincenzo; Brosius, Jeffrey W.; Hara, Hirosha

    1997-01-01

    A comparison of Skylab results with observations of the strong EUV lines of Fe XVI at 335 A and 361 A from the Goddard Solar EUV Rocket Telescope and Spectrograph (SERTS) flight of 1989 suggests that these lines, and perhaps others observed with SERTS, might offer good proxies for estimating the total coronal flux over important wavelength ranges. In this paper, we compare SERTS observations from a later, 1993 flight with simultaneous cospatial Yohkoh soft X-ray observations to test this suggestion over the energy range of the Soft X-ray Telescope (SXT) on Yohkoh. Both polynomial and power-law fits are obtained, and errors are estimated, for the SERTS lines of Fe XVI 335 A and 361 A, Fe XV 284 A and 417 A, and Mg IX 368 A. It is found that the power-law fits best cover the full range of solar conditions from quiet Sun through active region, though not surprisingly the 'cooler' Mg IX 368 A line proves to be a poor proxy. The quadratic polynomial fits yield fair agreement over a large range for all but the Mg IX line, but the linear fits fail conspicuously when extrapolated into the quiet Sun regime. The implications of this work for the He 11 304 A line formation problem are briefly considered. The paper concludes with a discussion of the value of these iron lines observed with SERTS for estimating stellar coronal fluxes, as observed for example with the EUVE satellite.

  1. Understanding Coronal Dimming and its Relation to Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Mason, J. P.; Woods, T. N.; Caspi, A.; Hock, R. A.

    2013-12-01

    When extreme ultraviolet (EUV) emitting material in the corona is lost during a coronal mass ejection (CME), the solar spectral irradiance is impacted and these effects are observed in data from the Solar Dynamics Observatory (SDO) EUV Variability Experiment (EVE) and Atmospheric Imaging Assembly (AIA). This process is one of the physical mechanisms that can lead to the observation of 'coronal dimming,' a phenomenon lasting eight hours on average and rarely persisting longer than one day. Other mechanisms that can cause observed dimming include obscuration of bright material (e.g., flare arcade) by dark material (e.g., filament), temperature evolution (e.g., cool plasma being heated causing transient decreases in characteristic emission lines), and propagation of global waves. Each of these processes has a unique spectral signature, which will be explained and exemplified. In particular, the 7 August 2010 M1.0 flare with associated ~870 km/s CME will be analyzed in detail using both AIA and EVE to demonstrate new techniques for isolating dimming due to the CME ('core dimming'). Further analysis will estimate CME mass and velocity using only parameterization of core dimming and compare these estimates to traditionally calculated CME kinetics.

  2. From Forbidden Coronal Lines to Meaningful Coronal Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Judge, P. G.; Habbal, S.; Landi, E.

    2013-12-01

    We review methods to measure magnetic fields within the corona using the polarized light in magnetic-dipole (M1) lines. We are particularly interested in both the global magnetic-field evolution over a solar cycle, and the local storage of magnetic free energy within coronal plasmas. We address commonly held skepticisms concerning angular ambiguities and line-of-sight confusion. We argue that ambiguities are, in principle, no worse than more familiar remotely sensed photospheric vector fields, and that the diagnosis of M1 line data would benefit from simultaneous observations of EUV lines. Based on calculations and data from eclipses, we discuss the most promising lines and different approaches that might be used. We point to the S-like [Fe xi] line ( J=2 to J=1) at 789.2 nm as a prime target line (for the Advanced Technology Solar Telescope (ATST) for example) to augment the hotter 1074.7 and 1079.8 nm Si-like lines of [Fe xiii] currently observed by the Coronal Multi-channel Polarimeter (CoMP). Significant breakthroughs will be made possible with the new generation of coronagraphs, in three distinct ways: i) through single-point inversions (which encompasses also the analysis of MHD wave modes), ii) using direct comparisons of synthetic MHD or force-free models with polarization data, and iii) using tomographic techniques.

  3. Mid-callosal plane determination using preferred directions from diffusion tensor images

    NASA Astrophysics Data System (ADS)

    Costa, André L.; Rittner, Letícia; Lotufo, Roberto A.; Appenzeller, Simone

    2015-03-01

    The corpus callosum is the major brain structure responsible for inter{hemispheric communication between neurons. Many studies seek to relate corpus callosum attributes to patient characteristics, cerebral diseases and psychological disorders. Most of those studies rely on 2D analysis of the corpus callosum in the mid-sagittal plane. However, it is common to find conflicting results among studies, once many ignore methodological issues and define the mid-sagittal plane based on precary or invalid criteria with respect to the corpus callosum. In this work we propose a novel method to determine the mid-callosal plane using the corpus callosum internal preferred diffusion directions obtained from diffusion tensor images. This plane is analogous to the mid-sagittal plane, but intended to serve exclusively as the corpus callosum reference. Our method elucidates the great potential the directional information of the corpus callosum fibers have to indicate its own referential. Results from experiments with five image pairs from distinct subjects, obtained under the same conditions, demonstrate the method effectiveness to find the corpus callosum symmetric axis relative to the axial plane.

  4. Coronal Structures in Cool Stars

    NASA Technical Reports Server (NTRS)

    Oliversen, Ronald (Technical Monitor); Dupree, Andrea K.

    2005-01-01

    We have extended our study of the structure of coronas in cool stars to very young stars still accreting from their surrounding disks. In addition we are pursing the connection between coronal X-rays and a powerful diagnostic line in the infrared, the He I 10830Angstrom transition of helium. Highlights of these are summarized below including publications during this reporting period and presentations. Spectroscopy of the infrared He I (lambda10830) line with KECK/NIRSPEC and IRTF/CSHELL and of the ultraviolet C III (lambda977) and O VI (lambda1032) emission with FUSE reveals that the classical T Tauri star TW Hydrae exhibits P Cygni profiles, line asymmetries, and absorption indicative of a continuous, fast (approximately 400 kilometers per second), hot (approximately 300,000 K) accelerating outflow with a mass loss rate approximately 10(exp -11)-10(exp -12) solar mass yr(sup -1) or larger. Spectra of T Tauri N appear consistent with such a wind. The source of the emission and outflow seems restricted to the stars themselves. Although the mass accretion rate is an order of magnitude less for TW Hya than for T Tau, the outflow reaches higher velocities at chromospheric temperatures in TW Hya. Winds from young stellar objects may be substantially hotter and faster than previously thought. The ultraviolet emission lines, when corrected for absorption are broad. Emission associated with the accretion flow and shock is likely to show turbulent broadening. We note that the UV line widths are significantly larger than the X-ray line widths. If the X-rays from TW Hya are generated at the accretion shock, the UV lines may not be directly associated with the shock. On the other hand, studies of X-ray emission in young star clusters, suggest that the strength of the X-ray emission is correlated with stellar rotation, thus casting doubt on an accretion origin for the X-rays. We are beginning to access the infrared spectral region where the He I 108308Angstroms transition

  5. Photospheric and coronal magnetic fields

    SciTech Connect

    Sheeley, N.R., Jr. )

    1991-01-01

    Research on small-scale and large-scale photospheric and coronal magnetic fields during 1987-1990 is reviewed, focusing on observational studies. Particular attention is given to the new techniques, which include the correlation tracking of granules, the use of highly Zeeman-sensitive infrared spectral lines and multiple lines to deduce small-scale field strength, the application of long integration times coupled with good seeing conditions to study weak fields, and the use of high-resolution CCD detectors together with computer image-processing techniques to obtain images with unsurpassed spatial resolution. Synoptic observations of large-scale fields during the sunspot cycle are also discussed. 101 refs.

  6. Sagittal Balance in Adolescent Idiopathic Scoliosis: A Radiographic Study of Spinopelvic Compensation After Selective Posterior Fusion of Thoracolumbar/Lumbar (Lenke 5C) Curves.

    PubMed

    Xu, Xi-Ming; Wang, Fei; Zhou, Xiao-Yi; Liu, Zi-Xuan; Wei, Xian-Zhao; Bai, Yu-Shu; Li, Ming

    2015-11-01

    The relationship between spinal sagittal alignment and pelvic parameters is well known in adolescent idiopathic scoliosis. However, few studies have reported the sagittal spinopelvic relationship after selective posterior fusion of thoracolumbar/lumbar (TL/L) curves. We evaluated the relationship between spinal sagittal alignment and the pelvis, and analyzed how the pelvic sagittal state is adjusted in Lenke type 5C patients. We conducted a retrospective study of 36 patients with Lenke type 5C curves who received selective posterior TL/L curve fusion. Coronal and spinopelvic sagittal parameters were pre and postoperatively compared. Pearson coefficients were used to analyze the correlation between all spinopelvic sagittal parameters before and after surgery. We also evaluated 3 pelvic morphologies (anteverted, normal, and retroverted) before and after surgery. Preoperatively, the mean pelvic incidence was 46.0°, with a pelvic tilt and sacral slope (SS) of 8.2° and 37.8°, respectively, and 25% (9/36) of patients had an anteverted pelvis, whereas the other 75% had a normal pelvis. Postoperatively, 42% (15/36) of patients had a retroverted pelvis, 53% (19/36) had a normal pelvis, and 2 patients had an anteverted pelvis. Logistic regression analyses yielded 2 factors that were significantly associated with the risk for a postoperative unrecovered anteverted pelvis, including increased lumbar lordosis (LL) (odds ratio [OR] 4.8, P = 0.029) and increased SS (OR 5.6, P = 0.018). Four factors were significantly associated with the risk of a postoperative newly anteverted pelvis, including LL at the final follow-up (OR 6.9, P = 0.009), increased LL (OR 8.9, P = 0.003), LL below fusion (OR 9.4, P = 0.002), and increased SS (OR 11.5, P = 0.001). The pelvic state may be adjusted after selective posterior TL/L curve fusion in Lenke 5C adolescent idiopathic scoliosis patients. It is difficult to improve an anteverted pelvis in patients who have an LL

  7. Magnetic shuffling of coronal downdrafts

    NASA Astrophysics Data System (ADS)

    Petralia, A.; Reale, F.; Orlando, S.

    2017-02-01

    Context. Channelled fragmented downflows are ubiquitous in magnetized atmospheres, and have recently been addressed based on an observation after a solar eruption. Aims: We study the possible back-effect of the magnetic field on the propagation of confined flows. Methods: We compared two 3D magnetohydrodynamic simulations of dense supersonic plasma blobs that fall down along a coronal magnetic flux tube. In one, the blobs move strictly along the field lines; in the other, the initial velocity of the blobs is not perfectly aligned with the magnetic field and the field is weaker. Results: The aligned blobs remain compact while flowing along the tube, with the generated shocks. The misaligned blobs are disrupted and merge through the chaotic shuffling of the field lines. They are structured into thinner filaments. Alfvén wave fronts are generated together with shocks ahead of the dense moving front. Conclusions: Downflowing plasma fragments can be chaotically and efficiently mixed if their motion is misaligned with field lines, with broad implications for disk accretion in protostars, coronal eruptions, and rain, for example. Movies associated to Figs. 2 and 3 are available at http://www.aanda.org

  8. Initiation of Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Moore, Ronald L.; Sterling, Alphonse C.

    2005-01-01

    This paper is a synopsis of the initiation of the strong-field magnetic explosions that produce large, fast coronal mass ejections. Cartoons based on observations are used to describe the inferred basic physical processes and sequences that trigger and drive the explosion. The magnetic field that explodes is a sheared-core bipole that may or may not be embedded in surrounding strong magnetic field, and may or may not contain a flux rope before it starts to explode. We describe three different mechanisms that singly or in combination trigger the explosion: (1) runaway internal tether-cutting reconnection, (2) runaway external tether-cutting reconnection, and (3) ideal MHD instability or loss or equilibrium. For most eruptions, high-resolution, high-cadence magnetograms and chromospheric and coronal movies (such as from TRACE and/or Solar-B) of the pre-eruption region and of the onset of the eruption and flare are needed to tell which one or which combination of these mechanisms is the trigger. Whatever the trigger, it leads to the production of an erupting flux rope. Using a simple model flux rope, we demonstrate that the explosion can be driven by the magnetic pressure of the expanding flux rope, provided the shape of the expansion is "fat" enough.

  9. Coronal Modeling and Synchronic Maps

    NASA Astrophysics Data System (ADS)

    Linker, Jon A.; Lionello, R.; Mikic, Z.; Riley, P.; Downs, C.; Henney, C. J.; Arge, C.

    2013-07-01

    MHD simulations of the solar corona rely on maps of the solar magnetic field (typically measured at the photosphere) for input as boundary conditions. These "synoptic" maps (available from a number of ground-based and space-based solar observatories), which are perhaps better described as "diachronic," are built up over a solar rotation. A well-known problem with this approach is that the maps contain data that is as much as 27 days old. The Sun's magnetic flux is always evolving, and these changes in the flux affect coronal and heliospheric structure. Flux evolution models can in principle provide a more accurate specification, by estimating the likely state of the photospheric magnetic field on unobserved portions of the Sun. The Air Force Data Assimilative Photospheric flux Transport (ADAPT) model (Arge et al. 2010), which incorporates data assimilation techniques into the Worden and Harvey (2000) flux evolution model, is especially well-suited for this purpose. In this presentation we describe the use of such "synchronic" maps with coronal models. We compare results using synchronic maps versus the traditional synoptic maps. Research supported by AFOSR, NASA, and NSF.

  10. Initiation of Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Moore, Ronald L.; Sterling, Alphonse C.

    2005-01-01

    This paper is a synopsis of the initiation of the strong-field magnetic explosions that produce large, fast coronal mass ejections. Cartoons based on observations are used to describe the inferred basic physical processes and sequences that trigger and drive the explosion. The magnetic field that explodes is a sheared-core bipole that may or may not be embedded in surrounding strong magnetic field, and may or may not contain a flux rope before it starts to explode. We describe three different mechanisms that singly or in combination trigger the explosion: (1) runaway internal tether-cutting reconnection, (2) runaway external tether-cutting reconnection, and (3) ideal MHD instability or loss or equilibrium. For most eruptions, high-resolution, high-cadence magnetograms and chromospheric and coronal movies (such as from TRACE and/or Solar-B) of the pre-eruption region and of the onset of the eruption and flare are needed to tell which one or which combination of these mechanisms is the trigger. Whatever the trigger, it leads to the production of an erupting flux rope. Using a simple model flux rope, we demonstrate that the explosion can be driven by the magnetic pressure of the expanding flux rope, provided the shape of the expansion is "fat" enough.

  11. Observational Signatures of Coronal Heating

    NASA Astrophysics Data System (ADS)

    Dahlburg, R. B.; Einaudi, G.; Ugarte-Urra, I.; Warren, H. P.; Rappazzo, A. F.; Velli, M.; Taylor, B.

    2016-12-01

    Recent research on observational signatures of turbulent heating of a coronal loop will be discussed. The evolution of the loop is is studied by means of numericalsimulations of the fully compressible three-dimensionalmagnetohydrodynamic equations using the HYPERION code. HYPERION calculates the full energy cycle involving footpoint convection, magnetic reconnection,nonlinear thermal conduction and optically thin radiation.The footpoints of the loop magnetic field are convected by random photospheric motions. As a consequence the magnetic field in the loop is energized and develops turbulent nonlinear dynamics characterized by the continuous formation and dissipation of field-aligned current sheets: energy is deposited at small scales where heating occurs. Dissipation is non-uniformly distributed so that only a fraction of thecoronal mass and volume gets heated at any time. Temperature and density are highly structured at scales which, in the solar corona, remain observationally unresolved: the plasma of the simulated loop is multi-thermal, where highly dynamical hotter and cooler plasma strands arescattered throughout the loop at sub-observational scales. Typical simulated coronal loops are 50000 km length and have axial magnetic field intensities ranging from 0.01 to 0.04 Tesla.To connect these simulations to observations the computed numberdensities and temperatures are used to synthesize the intensities expected inemission lines typically observed with the Extreme ultraviolet Imaging Spectrometer(EIS) on Hinode. These intensities are then employed to compute differentialemission measure distributions, which are found to be very similar to those derivedfrom observations of solar active regions.

  12. Coronal manifestations of preflare activity

    NASA Technical Reports Server (NTRS)

    Schmahl, E. J.; Webb, D. F.; Woodgate, B.; Waggett, P.; Bentley, R.; Hurford, G.; Schadee, A.; Schrijver, J.; Harrison, R.; Martens, P.

    1986-01-01

    A variety of coronal manifestations of precursors or preheating for flares are discussed. Researchers found that almost everyone with a telescope sees something before flares. Whether an all-encompassing scenario will ever be developed is not at all clear at present. The clearest example of preflare activity appears to be activated filaments and their manifestations, which presumably are signatures of a changing magnetic field. But researchers have seen two similar eruptions, one without any evidence of emerging flux (Kundu et al., 1985) and the other with colliding poles (Simon et al., 1984). While the reconnection of flux is generally agreed to be required to energize a flare, the emergence of flux from below (at least on short timescales and in compact regions) does not appear to be a necessary condition. In some cases the cancelling of magnetic flux (Martin, 1984) by horizontal motions instead may provide the trigger (Priest, 1985) Researchers found similarities and some differences between these and previous observations. The similarities, besides the frequent involvement of filaments, include compact, multiple precursors which can occur both at and near (not at) the flare site, and the association between coronal sources and activity lower in the atmosphere (i.e., transition zone and chromosphere).

  13. Normative segment-specific axial and coronal angulation corridors of subaxial cervical column in axial rotation.

    PubMed

    Yoganandan, Narayan; Stemper, Brian D; Pintar, Frank A; Baisden, Jamie L; Shender, Barry S; Paskoff, Glenn

    2008-03-01

    In contrast to clinical studies wherein loading magnitudes are indeterminate, experiments permit controlled and quantifiable moment applications, record kinematics in multiple planes, and allow derivation of moment-angulation corridors. Axial and coronal moment-angulation corridors were determined at every level of the subaxial cervical spine, expressed as logarithmic functions, and level-specificity of range of motion and neutral zones were evaluated. segmental primary axial and coupled coronal motions do not vary by level. Although it is known that cervical spine responses are coupled, segment-specific corridors of axial and coronal kinematics under axial twisting moments from healthy normal spines are not reported. Ten human cadaver columns (23-44 years, mean: 34 +/- 6.8) were fixed at the ends and targets were inserted to each vertebra to obtain kinematics in axial and coronal planes. The columns were subjected to pure axial twisting moments. Range of motion and neutral zone for primary-axial and coupled-coronal rotation components were determined at each spinal level. Data were analyzed using factorial analysis of variance. Moment-rotation angulations were expressed using logarithmic functions, and mean +/-1 standard deviation corridors were derived at each level for both components. Moment-angulations responses were nonlinear. Each segmental curve for both components was well represented by a logarithmic function (r2 > 0.95). Factorial analysis of variance indicated that the biomechanical metrics are spinal level-specific (P < 0.05). Axial and coronal angulations of cervical spinal columns show statistically different level-specific responses. The presentation of moment-angulation corridors for both metrics forms a dataset for the normal population. These segment-specific nonlinear corridors may help clinicians assess dysfunction or instability. These data will assist mathematical models of the spine in improved validation and lead to efficacious design of

  14. Professionalism in practice: the Coroner's Court.

    PubMed

    Griffith, Richard

    2017-01-02

    A coroner recently declared a district nursing service as unfit for purpose following the death of a patient and held the care given by district nurses was unprofessional and contributed to the patient's decline and death. In this article Richard Griffith considers the coroners concerns in relation to the professional standards imposed on district nurses.

  15. Deep coronal hole associated with quiescent filament

    NASA Astrophysics Data System (ADS)

    Kesumaningrum, Rasdewita; Herdiwidjaya, Dhani

    2014-03-01

    We present a study of the morphology of quiescent filament observed by H-alpha Solar Telescope at Bosscha Observatory in association with coronal hole observed by Atmospheric Imaging Assembly (AIA) instrument in 193 Å from Solar Dynamics Observatory. H-alpha images were processed by imaging softwares, namely Iris 5.59 and ImageJ, to enhance the signal to noise ratio and to identify the filament features associated with coronal hole. For images observed on October 12, 2011, November 14, 2011 and January 2, 2012, we identified distinct features of coronal holes above the quiescent filaments. This associated coronal holes have filament-like morphology with a thick long thread as it's `spine', defined as Deep Coronal Hole. Because of strong magnetic field of sunspot, these filaments and coronal holes emerged far from active region and lasted for several days. It is interesting as for segmented filament, deep coronal holes above the filaments lasted for a quite long period of time and merged. This association between filament and deep coronal hole can be explained by filament magnetic loop.

  16. Small-scale coronal structure, part 3

    NASA Technical Reports Server (NTRS)

    Webb, David F.

    1986-01-01

    Recent observations and models pertaining specifically to solar coronal bright points (BPs) and generally to small-scale coronal structure are reviewed. Two questions were addressed: What is the degree of correspondence among various alleged signatures of BPs at different levels of atmosphere and what can PBs tell about the emerging flux spectrum of the sun?

  17. Temporomandibular joint computed tomography: development of a direct sagittal technique

    SciTech Connect

    van der Kuijl, B.; Vencken, L.M.; de Bont, L.G.; Boering, G. )

    1990-12-01

    Radiology plays an important role in the diagnosis of temporomandibular disorders. Different techniques are used with computed tomography offering simultaneous imaging of bone and soft tissues. It is therefore suited for visualization of the articular disk and may be used in patients with suspected internal derangements and other disorders of the temporomandibular joint. Previous research suggests advantages to direct sagittal scanning, which requires special positioning of the patient and a sophisticated scanning technique. This study describes the development of a new technique of direct sagittal computed tomographic imaging of the temporomandibular joint using a specially designed patient table and internal light visor positioning. No structures other than the patient's head are involved in the imaging process, and misleading artifacts from the arm or the shoulder are eliminated. The use of the scanogram allows precise correction of the condylar axis and selection of exact slice level.

  18. Spinal pedicle subtraction osteotomy for fixed sagittal imbalance patients

    PubMed Central

    Hyun, Seung-Jae; Kim, Yongjung J; Rhim, Seung-Chul

    2013-01-01

    In addressing spinal sagittal imbalance through a posterior approach, the surgeon now may choose from among a variety of osteotomy techniques. Posterior column osteotomies such as the facetectomy or Ponte or Smith-Petersen osteotomy provide the least correction, but can be used at multiple levels with minimal blood loss and a lower operative risk. Pedicle subtraction osteotomies provide nearly 3 times the per-level correction of Ponte/Smith-Petersen osteotomies; however, they carry increased technical demands, longer operative time, and greater blood loss and associated significant morbidity, including neurological injury. The literature focusing on pedicle subtraction osteotomy for fixed sagittal imbalance patients is reviewed. The long-term overall outcomes, surgical tips to reduce the complications and suggestions for their proper application are also provided. PMID:24340276

  19. Sagittal evaluation of usual standing and sitting spinal posture.

    PubMed

    Claeys, Kurt; Brumagne, Simon; Deklerck, Jan; Vanderhaeghen, Jacques; Dankaerts, Wim

    2016-04-01

    Postural rehabilitation often plays an important role in the management of non-specific low back pain. While cervical and lumbar correlations have been demonstrated previously, the different role of the pelvis and the thoracic spine for postural control in sitting and standing remains unclear. The aim of this study was to investigate postural correlations between all spinal regions in standing and sitting. Based on digital photographs eight postural angles were analyzed in 99 young healthy persons. Pearson correlations between different postural angles were calculated. In sitting pelvic tilt demonstrated mostly medium correlations with five out of seven other postural angles, compared to three in standing. In standing trunk angle showed five out of seven mostly medium correlations with other regions compared to four out of seven in usual sitting. The low and different correlations suggest a large between-subject variability in sagittal spinal posture, without the existence of any optimal sagittal posture. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. An articulatory view of Kinyarwanda coronal harmony.

    PubMed

    Walker, Rachel; Byrd, Dani; Mpiranya, Fidèle

    2008-12-01

    Coronal harmony in Kinyarwanda causes alveolar fricatives to become postalveolar preceding a postalveolar fricative within a stem. Alveolar and postalveolar stops, affricates and palatals block coronal harmony, but the flap and non-coronal consonants are reported to be transparent. Kinematic data on consonant production in Kinyarwanda were collected using electromagnetic articulography. The mean angle for the line defined by receivers placed on the tongue tip and blade was calculated over the consonant intervals. Mean angle reliably distinguished alveolar and postalveolar fricatives, with alveolars showing a lower tip relative to blade. Mean angle during transparent non-coronal consonants showed a higher tip relative to blade than in contexts without harmony, and the mean angle during transparent [m] was not significantly different than during postalveolar fricatives. This is consistent with a model where Kinyarwanda coronal harmony extends a continuous tip-blade gesture, causing it to be present during 'transparent' segments, but without perceptible effect.

  1. An articulatory view of Kinyarwanda coronal harmony⁕

    PubMed Central

    Walker, Rachel; Byrd, Dani; Mpiranya, Fidèle

    2009-01-01

    Coronal harmony in Kinyarwanda causes alveolar fricatives to become postalveolar preceding a postalveolar fricative within a stem. Alveolar and postalveolar stops, affricates and palatals block coronal harmony, but the flap and non-coronal consonants are reported to be transparent. Kinematic data on consonant production in Kinyarwanda were collected using electromagnetic articulography. The mean angle for the line defined by receivers placed on the tongue tip and blade was calculated over the consonant intervals. Mean angle reliably distinguished alveolar and postalveolar fricatives, with alveolars showing a lower tip relative to blade. Mean angle during transparent non-coronal consonants showed a higher tip relative to blade than in contexts without harmony, and the mean angle during transparent [m] was not significantly different than during postalveolar fricatives. This is consistent with a model where Kinyarwanda coronal harmony extends a continuous tip-blade gesture, causing it to be present during ‘transparent’ segments, but without perceptible effect. PMID:20027237

  2. Force-Induced Craniosynostosis in the Murine Sagittal Suture

    PubMed Central

    Oppenheimer, Adam J.; Rhee, Samuel T.; Goldstein, Steven A.; Buchman, Steven R.

    2010-01-01

    BACKGROUND The etiology of non-syndromic craniosynostosis remains elusive. While compressive forces have been implicated in premature suture fusion, conclusive evidence of force-induced craniosynostosis is lacking. The purpose of this study was to determine if cyclical loading of the murine calvarium could induce suture fusion. METHODS Calvarial coupons from post-natal day 21, B6CBA wild-type mice (n = 18) were harvested and cultured. A custom appliance capable of delivering controlled, cyclical, compressive loads was applied perpendicular to the sagittal suture within the coupon in vitro. Nine coupons were subjected to 0.3g of force for 30 minutes each day for a total of 14 days. A control group of nine coupons was clamped in the appliance without loading. Analysis of suture phenotype was performed using alkaline phosphatase and H&E staining techniques, as well as in situ hybridization analysis using Bone Sialoprotein (BSP). RESULTS Control group sagittal sutures—which normally remain patent in mice—showed their customary histological appearance. In contradistinction, sagittal sutures subjected to cyclic loading showed histological evidence of premature fusion (craniosynostosis). In addition, alkaline phosphatase activity and BSP expression was observed to be increased in the experimental group when compared to matched controls. CONCLUSIONS An in vitro model of forced-induced craniosynostosis has been devised. Premature fusion of the murine sagittal suture was induced with the application of controlled, cyclical, compressive loads. These results implicate abnormal forces in the development of non-syndromic craniosynostosis, which supports our global hypothesis that epigenetic phenomena have a crucial role in the pathogenesis of craniosynostosis. PMID:19952640

  3. Ability of sagittal kinematic variables to estimate ground reaction forces and joint kinetics in running.

    PubMed

    Wille, Christa M; Lenhart, Rachel L; Wang, Sijian; Thelen, Darryl G; Heiderscheit, Bryan C

    2014-10-01

    Controlled laboratory study, cross-sectional design. To determine if sagittal kinematic variables can be used to estimate select running kinetics. Excessive loading during running has been implicated in a variety of injuries, yet this information is typically not assessed during a standard clinical examination. Developing a clinically feasible strategy to estimate ground reaction forces and joint kinetics may improve the ability to identify those at an increased risk of injury. Three-dimensional kinematics and ground reaction forces of 45 participants were recorded during treadmill running at self-selected speed. Kinematic variables used to estimate specific kinetic metrics included vertical excursion of the center of mass, foot inclination angle at initial contact, horizontal distance between the center of mass and heel at initial contact, knee flexion angle at initial contact, and peak knee flexion angle during stance. Linear mixed-effects models were fitted to explore the association between the kinetic and kinematic measures, including step rate and sex, with final models created using backward variable selection. Models were developed to estimate peak knee extensor moment (R(2) = 0.43), energy absorbed at the knee during loading response (R(2) = 0.58), peak patellofemoral joint reaction force (R(2) = 0.55), peak vertical ground reaction force (R(2) = 0.48), braking impulse (R(2) = 0.50), and average vertical loading rate (R(2) = 0.04). Our findings suggest that insights into important running kinetics can be obtained from a subset of sagittal plane kinematics common to a clinical running analysis. Of note, the limb posture at initial contact influenced subsequent loading patterns in stance.

  4. Correlation between condylar position and different sagittal skeletal facial types.

    PubMed

    Paknahad, Maryam; Shahidi, Shoaleh; Abbaszade, Hajar

    2016-09-01

    Condylar position may play a key role in the stability of orthodontic treatment of patients presenting with different skeletal patterns. The aim of the present study was to assess via cone beam computed tomography (CBCT) correlations between condylar position and sagittal skeletal relationship. Condylar positions in CBCT images of 20 patients presenting with a Class I skeletal pattern, 20 with a Class II skeletal pattern, and 20 with a Class III skeletal pattern were evaluated retrospectively. The χ (2) test was used to assess the correlation between condylar position and sagittal skeletal relationships. The condyles were anteriorly positioned in patients with Class II skeletal pattern in comparison with those with Class I and III skeletal patterns. No significant differences in condylar position between Class I and Class III subjects were detected. A significant correlation between condylar position and sagittal skeletal patterns was observed in the present study. This relationship should be considered when planning and carrying out the appropriate orthodontic treatment for temporomandibular anomalies.

  5. Image-based reconstruction of the Newtonian dynamics of solar coronal ejecta

    NASA Astrophysics Data System (ADS)

    Uritsky, Vadim

    2016-10-01

    We present a new methodology for analyzing rising and falling dynamics of unstable coronal material as represented by high-cadence SDO AIA images. The technique involves an adaptive spatiotemporal tracking of propagating intensity gradients and their characterization in terms of time-evolving areas swept out by the position vector originated from the Sun disk center. The measured values of the areal velocity and acceleration are used to obtain quantitative information on the angular momentum and acceleration along the paths of the rising and falling coronal plasma. In the absence of other forces, solar gravitation results in purely ballistic motions consistent with the Kepler’s second law; non-central forces such as the Lorentz force introduce non-zero torques resulting in more complex motions. The developed algorithms enable direct evaluation of the line-of-sight component of the net torque applied to a unit mass of the ejected coronal material which is proportional to the image-plane projection of the observed areal acceleration. The current implementation of the method cannot reliably distinguish torque modulations caused by the coronal force field from those imposed by abrupt changes of plasma mass density and nontrivial projection effects. However, it can provide valid observational constraints on the evolution of large-scale unstable magnetic topologies driving major solar-coronal eruptions as demonstrated in the related talk by B. Thompson et al.

  6. [Usefulness of curved coronal MPR imaging for the diagnosis of cervical radiculopathy].

    PubMed

    Inukai, Chikage; Inukai, Takashi; Matsuo, Naoki; Shimizu, Ikuo; Goto, Hisaharu; Takagi, Teruhide; Takayasu, Masakazu

    2010-03-01

    In surgical treatment of cervical radiculopathy, localization of the responsible lesions by various imaging modalities is essential. Among them, MRI is non-invasive and plays a primary role in the assessment of spinal radicular symptoms. However, demonstration of nerve root compression is sometimes difficult by the conventional methods of MRI, such as T1 weighted (T1W) and T2 weighted (T2W) sagittal or axial images. We have applied a new technique of curved coronal multiplanar reconstruction (MPR) imaging for the diagnosis of cervical radiculopathy. Ten patients (4 male, 6 female) with ages between 31 and 79 year-old, who had clinical diagnosis of cervical radiculopathy, were included in this study. Seven patients underwent anterior key-hole foraminotomy to decompress the nerve root with successful results. All the patients had 3D MRI studies, such as true fast imaging with steady-state precession (FISP), 3DT2W sampling perfection with application optimized contrasts using different fillip angle evolution (SPACE), and 3D multi-echo data image combination (MEDIC) imagings in addition to the routine MRI (1.5 T Avanto, Siemens, Germany) with a phased array coil. The curved coronal MPR images were produced from these MRI data using a workstation. The nerve root compression was diagnosed by curved coronal MPR images in all the patients. The compression sites were compatible with those of the operative findings in 7 patients, who underwent surgical treatment. The MEDIC imagings were the most demonstrable to visualize the nerve root, while the 3D-space imagings were the next. The curved coronal MPR imaging is useful for the diagnosis of accurate localization of the compressing lesions in patients with cervical radiculopathy.

  7. Effect of Preoperative Sagittal Balance on Cervical Laminoplasty Outcomes.

    PubMed

    Oshima, Yasushi; Takeshita, Katsushi; Taniguchi, Yuki; Matsubayashi, Yoshitaka; Doi, Toru; Ohya, Junichi; Soma, Kazuhito; Kato, So; Oka, Hiroyuki; Chikuda, Hirotaka; Tanaka, Sakae

    2016-11-01

    Retrospective case series. To clarify how preoperative global sagittal imbalance influences outcomes in patients with cervical compression myelopathy undergoing cervical laminoplasty. The influence of sagittal balance on outcomes of cervical laminoplasty remains uncertain. The authors retrospectively reviewed data of 106 patients who underwent double-door cervical laminoplasty between 2004 and 2011 and investigated the influence of the C7 sagittal vertical axis (SVA) on outcome scores. Primary outcomes used were Japanese Orthopedic Association (JOA) scores, Numerical Rating Scale for neck or arm pain, the Short Form 36 Health Survey (physical and mental component summary scores ), and the Neck Disability Index (NDI). Ninety-two patients with complete data were eligible for inclusion. The preoperative C7 SVA was ≤5 cm in 64 patients (69.6%) and > 5 cm in 28 (30.4%). We compared each parameter by the magnitude of spinal sagittal balance (preoperative C7 SVA > 5 cm vs. C7 SVA ≤ 5 cm) after adjusting for age via the least square mean analysis because the average age was significantly higher in patients with C7 SVA > 5 cm. As for the radiographic parameters, both C2-7 SVA and C7 SVA were larger in patients when the C7 SVA was > 5 cm. Numerical Rating Scale for postoperative arm pain, postoperative JOA scores, and both pre- and postoperative physical component summary and NDI were worse in patients with C7 SVA > 5 cm; however, the JOA score recovery rate and changes in physical component summary and NDI were not significantly different. Postoperative functional outcome scores were significantly lower in patients with C7 SVA > 5 cm, although the improvement after cervical laminoplasty was not greatly affected. The involvement of global sagittal balance and cervical regional alignment should be considered in evaluating surgical outcomes for patients undergoing cervical laminoplasty. 4.

  8. Recent advances in coronal heating

    PubMed Central

    De Moortel, Ineke; Browning, Philippa

    2015-01-01

    The solar corona, the tenuous outer atmosphere of the Sun, is orders of magnitude hotter than the solar surface. This ‘coronal heating problem’ requires the identification of a heat source to balance losses due to thermal conduction, radiation and (in some locations) convection. The review papers in this Theo Murphy meeting issue present an overview of recent observational findings, large- and small-scale numerical modelling of physical processes occurring in the solar atmosphere and other aspects which may affect our understanding of the proposed heating mechanisms. At the same time, they also set out the directions and challenges which must be tackled by future research. In this brief introduction, we summarize some of the issues and themes which reoccur throughout this issue. PMID:25897095

  9. Coronal Loops Reveal Magnetic Dance

    NASA Image and Video Library

    2017-09-28

    Magnetic Dance: Solar material traces out giant magnetic fields soaring through the sun to create what's called coronal loops. Here they can be seen as white lines in a sharpened AIA image from Oct. 24, 2014, laid over data from SDO's Helioseismic Magnetic Imager, which shows magnetic fields on the sun's surface in false color. Credit: NASA/SDO/HMI/AIA/LMSAL Read more: www.nasa.gov/content/goddard/sdo-telescope-collects-its-1... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  10. Coronal Structure: Legacy of EUVE

    NASA Technical Reports Server (NTRS)

    Dupree, Andrea K,

    1999-01-01

    During this past school year, the Smithsonian Predoctoral student, Jorge Sanz-Forcada, began work on this Ph.D. thesis research which will focus on the coronal structure of active cool binary stars. He developed a semi-automatic algorithm to derive the emission measure distribution from EUVE spectra using the latest atomic parameters. To date, he has modeled our long EUVE pointing on lambda And that occurred in the fall of 1998, and has reduced and modeled spectra from EUVE pointings on AR Lac and UX Ari. Some of these observations were made simultaneous with the Advanced Satellite for Cosmology and Physics (ASCA) satellite, and the results reported at the HEAD meeting in Spring 1999.

  11. Coronal Mass Ejections travel time

    NASA Astrophysics Data System (ADS)

    Braga, Carlos Roberto; Souza de Mendonça, Rafael Rodrigues; Dal Lago, Alisson; Echer, Ezequiel

    2017-10-01

    Coronal mass ejections (CMEs) are the main source of intense geomagnetic storms when they are earthward directed. Studying their travel time is a key-point to understand when the disturbance will be observed at Earth. In this work, we study the CME that originated the interplanetary disturbance observed on 2013/10/02. According to the observations, the CME that caused the interplanetary disturbance was ejected on 2013/09/29. We obtained the CME speed and estimate of the time of arrival at the Lagrangian Point L1 using the concept of expansion speed. We found that observed and estimated times of arrival of the shock differ between 2 and 23 hours depending on method used to estimate the radial speed.

  12. Simulations of coronal disconnection events

    SciTech Connect

    Linker, J.A.; Van Hoven, G. ); McComas, D.J. )

    1992-09-01

    The lack of evidence for magnetic disconnection of coronal mass ejection (CMEs) from the Sun has long been a puzzle, as it implies a buildup of the interplanetary magnetic field (IMF) magnitude over time. Such a buildup is ruled out by observations. Magnetic reconnection above helmet streamer configurations could provide a mechanism for maintaining the observed relative constancy of the (IMF) [McComas et al., 1989]; McComas et al. [1991] showed observational evidence of reconnection above a streamer. The authors investigate this interpretation using time-dependent MHD simulations. They model the opening of new magnetic flux on the Sun (as might occur in a CME or other transient event) as an increase in magnetic flux at the poles of a simulated corona. They find that this perturbation can in fact cause reconnection above an equatorial helmet streamer, and the resultant density signature is similar to the observations of McComas et al. [1991].

  13. Recent advances in coronal heating.

    PubMed

    De Moortel, Ineke; Browning, Philippa

    2015-05-28

    The solar corona, the tenuous outer atmosphere of the Sun, is orders of magnitude hotter than the solar surface. This 'coronal heating problem' requires the identification of a heat source to balance losses due to thermal conduction, radiation and (in some locations) convection. The review papers in this Theo Murphy meeting issue present an overview of recent observational findings, large- and small-scale numerical modelling of physical processes occurring in the solar atmosphere and other aspects which may affect our understanding of the proposed heating mechanisms. At the same time, they also set out the directions and challenges which must be tackled by future research. In this brief introduction, we summarize some of the issues and themes which reoccur throughout this issue.

  14. Modeling Interplanetary Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Riley, Pete

    2004-01-01

    Heliospheric models of Coronal Mass Ejection (CME) propagation and evolution provide an important insight into the dynamics of CMEa and are a valuable tool for interpreting interplanetary in situ observations. Moreover, they represent a virtual laboratory for exploring conditions and regions of space that are not conveniently or currently accessible by spacecraft. In this review I summarize recent advances in modeling the properties and evolution of CMEs in the solar wind. In particular, I will focus on: (1) the types of ICME models; (2) the boundary conditions that are imposed, (3) the role of the ambient solar wind; (4) predicting new phenomena; and (5) distinguishing between competing CME initiation mechanisms. I will conclude by discussing what topics will likely be important for models to address in the future.

  15. Initiation of a coronal transient

    SciTech Connect

    Low, B.C.; Munro, R.H.; Fisher, R.R.

    1982-03-01

    This paper analyzes the coronal transient/eruptive prominence event of 1980 August 5 observed by the Mauna Loa experiment system. This event yielded data on the early development of the transient in the low corona between 1.2 R/sub sun/ and 2.2 R/sub sun/, information which was not available when earlier attempts were made to explain transient phenomena. The transient's initial appearance in the form of a rising density-depleted structure, prior to the eruption of the associated prominence, can be explained as an effect of magnetic buoyancy. The data indicate that this transient has a density depletion of 17% to 33% relative to an undisturbed corona which is approximately isothermal with a temperature of 1.5 x 10/sup 6/ K and a coronal density of 1.0 x 10/sup 9/ cm/sup -3/ at the base of the corona. The height versus base length relationship of the evolving transient resembles, remarkably well, the theoretical predictions obtained from a quasi-static model of a margnetically buoyant loop system. By matching this relationship with the theoretical model, we estimate the magnetic field at the base of the transient to be between 2 and 3 gauss. It is also shown that the initial, nearly constant speed of the top of the transient, 80 +- 20 km s/sup -1/, is consistent with a theoretical estimate calculated from the quasi-static model. These results suggest that some transients are not initiated impulsively, the initial stage of the development being driven by a quasi-static response to a slow change in magnetic field conditions at the base of the corona.

  16. FORWARD: A Toolset for Multiwavelength Coronal Magnetometry

    NASA Technical Reports Server (NTRS)

    Gibson, Sarah E.; Kucera, Therese A.; White, Stephen M.; Dove, James B.; Fan, Yuhong; Forland, Blake C.; Rachmeler, Laurel A.; Downs, Cooper; Reeves, Katharine K.

    2016-01-01

    Determining the 3D coronal magnetic field is a critical, but extremely difficult problem to solve. Since different types of multiwavelength coronal data probe different aspects of the coronal magnetic field, ideally these data should be used together to validate and constrain specifications of that field. Such a task requires the ability to create observable quantities at a range of wavelengths from a distribution of magnetic field and associated plasma i.e., to perform forward calculations. In this paper we describe the capabilities of the FORWARD SolarSoft IDL package, a uniquely comprehensive toolset for coronal magnetometry. FORWARD is a community resource that may be used both to synthesize a broad range of coronal observables, and to access and compare synthetic observables to existing data. It enables forward fitting of specific observations, and helps to build intuition into how the physical properties of coronal magnetic structures translate to observable properties. FORWARD can also be used to generate synthetic test beds from MHD simulations in order to facilitate the development of coronal magnetometric inversion methods, and to prepare for the analysis of future large solar telescope data.

  17. FORWARD: A Toolset for Multiwavelength Coronal Magnetometry

    NASA Technical Reports Server (NTRS)

    Gibson, Sarah E.; Kucera, Therese A.; White, Stephen M.; Dove, James B.; Fan, Yuhong; Forland, Blake C.; Rachmeler, Laurel A.; Downs, Cooper; Reeves, Katharine K.

    2016-01-01

    Determining the 3D coronal magnetic field is a critical, but extremely difficult problem to solve. Since different types of multiwavelength coronal data probe different aspects of the coronal magnetic field, ideally these data should be used together to validate and constrain specifications of that field. Such a task requires the ability to create observable quantities at a range of wavelengths from a distribution of magnetic field and associated plasma i.e., to perform forward calculations. In this paper we describe the capabilities of the FORWARD SolarSoft IDL package, a uniquely comprehensive toolset for coronal magnetometry. FORWARD is a community resource that may be used both to synthesize a broad range of coronal observables, and to access and compare synthetic observables to existing data. It enables forward fitting of specific observations, and helps to build intuition into how the physical properties of coronal magnetic structures translate to observable properties. FORWARD can also be used to generate synthetic test beds from MHD simulations in order to facilitate the development of coronal magnetometric inversion methods, and to prepare for the analysis of future large solar telescope data.

  18. FORWARD: A toolset for multiwavelength coronal magnetometry

    NASA Astrophysics Data System (ADS)

    Gibson, Sarah; Kucera, Therese; White, Stephen; Dove, James; Fan, Yuhong; Forland, Blake; Rachmeler, Laurel; Downs, Cooper; Reeves, Katharine

    2016-03-01

    Determining the 3D coronal magnetic field is a critical, but extremely difficult problem to solve. Since different types of multiwavelength coronal data probe different aspects of the coronal magnetic field, ideally these data should be used together to validate and constrain specifications of that field. Such a task requires the ability to create observable quantities at a range of wavelengths from a distribution of magnetic field and associated plasma -- i.e., to perform forward calculations. In this paper we describe the capabilities of the FORWARD SolarSoft IDL package, a uniquely comprehensive toolset for coronal magnetometry. FORWARD is a community resource that may be used both to synthesize a broad range of coronal observables, and to access and compare synthetic observables to existing data. It enables forward fitting of specific observations, and helps to build intuition into how the physical properties of coronal magnetic structures translate to observable properties. FORWARD can also be used to generate synthetic test beds from MHD simulations in order to facilitate the development of coronal magnetometric inversion methods, and to prepare for the analysis of future large solar telescope data.

  19. An Evaluation of Benchmarks for Esthetic Orientation of the Occlusal Plane.

    PubMed

    Priest, George; Wilson, Michael G

    2017-04-01

    This patient study was designed to measure the validity of both the horizontal and Camper's planes, which are used as benchmarks to reestablish the sagittal orientation of the occlusal plane angles in dental rehabilitation. Profile digital photographs were made of the first 100 consenting dentate patients as they closed on an occlusal plane analyzer while maintaining natural head posture. Using a digital screen protractor, three angles were measured: the occlusal plane angle relative to the horizontal plane, and the angle between the occlusal plane and Camper's plane from both the superior and inferior borders of the tragus of the ear. The angle between the occlusal plane and the horizontal reference plane for the 100 patients ranged from -8.72° to +18.08° (mean +3.25°); the angle between the occlusal plane and Camper's plane, from the superior border of the tragus to the ala of the nose demonstrated a range from -8.49° to +15.16° (mean +3.03°); and the angle between Camper's plane, from the inferior border of the tragus to the ala of the nose and the occlusal plane demonstrated a range from -15.57° to +9.15° (mean -4.09°). Occlusal plane angles measured in this patient population with natural dentitions demonstrated a relatively small mean deviation from both the horizontal plane and Camper's plane when using the superior border of the tragus as the distal reference point, but the range was quite broad and could result in unacceptable occlusal plane angles in many patients undergoing dental rehabilitation. Both Camper's plane and the horizontal reference plane may be acceptable initial reference planes for oral rehabilitation, but additional anatomic and esthetic parameters are required for verification of an esthetically pleasing occlusal plane angle. © 2016 by the American College of Prosthodontists.

  20. Sagittal standing posture and its association with spinal pain: a school-based epidemiological study of 1196 Flemish adolescents before age at peak height velocity.

    PubMed

    Dolphens, Mieke; Cagnie, Barbara; Coorevits, Pascal; Vanderstraeten, Guy; Cardon, Greet; Dʼhooge, Roseline; Danneels, Lieven

    2012-09-01

    Cross-sectional baseline data set on the sagittal standing posture of 1196 adolescents. To describe and quantify common variations in the sagittal standing alignment in boys and girls who are in the same phase of growth and to explore the association between habitual standing posture and measures for spinal pain. Data on postural characteristics and spinal pain measures in adolescence are sparse, especially when somatic and biological maturity status is to be considered. Our understanding of the relationship between standing posture in the sagittal plane and spinal pain is also deficient. A total of 639 boys (age [mean ± SD], 12.6 ± 0.54 yr) and 557 girls (10.6 ± 0.47 yr), with predicted years from peak height velocity (PHV) being 1.2 ± 0.71 and 1.2 ± 0.59 pre-PHV, respectively, were studied. Postural examination included the assessment of global alignment and local spinopelvic characteristics, using post hoc analyses of digital images and direct body measurements (palpation, digital inclinometry, and wheeled accelerometry). Spinal pain experience was assessed by questionnaire. A wide interindividual variation in sagittal posture characteristics was observed. Logistic regression analyses yielded global alignment parameters to be associated with low back pain (lifetime prevalence), neck pain (lifetime prevalence, 1-mo prevalence, and doctor visit), and thoracic spine pain (doctor visit) outcome measures. None of the included local spinopelvic parameters could be identified as an associated factor with measures of spinal pain. The orientation of gross body segments with respect to the gravity line seems superior to local spinopelvic features in terms of clinical importance, at least in the current pre-PHV cohort. Opportunities may exist for postural subgrouping strategies to begin with global alignment parameters in order to gain further insight into the relationship between sagittal alignment and the relative risk of developing spinal pain/seeking medical

  1. Comparing viewer and array mental rotations in different planes

    NASA Technical Reports Server (NTRS)

    Carpenter, M.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

    2001-01-01

    Participants imagined rotating either themselves or an array of objects that surrounded them. Their task was to report on the egocentric position of an item in the array following the imagined rotation. The dependent measures were response latency and number of errors committed. Past research has shown that self-rotation is easier than array rotation. However, we found that imagined egocentric rotations were as difficult to imagine as rotations of the environment when people performed imagined rotations in the midsagittal or coronal plane. The advantages of imagined self-rotations are specific to mental rotations performed in the transverse plane.

  2. The identification of coordination constraints across planes of motion.

    PubMed

    Serrien, D J; Bogaerts, H; Suy, E; Swinnen, S P

    1999-09-01

    Two dominant coordination constraints have been identified during isofrequency conditions in previous work: the egocentric constraint, i.e., simultaneous activation of homologous muscle groups, and the allocentric constraint, i.e., moving the segments in the same direction in extrinsic space. To verify their generalization, bimanual drawing movements were performed in different planes of motion (transverse, frontal, sagittal, frontal-transverse) according to the in-phase and anti-phase mode along the X- and Y-axes. Convergent findings were obtained across the transverse, frontal, and frontal-transverse planes. The in-phase mode along both axes was performed most accurately/consistently, whereas the anti-phase mode resulted in a deterioration of the coordination pattern and this effect was most pronounced when the latter mode was introduced with respect to both dimensions. For sagittal plane motions, the in-phase mode was again superior but the second most optimal configuration was the anti-phase mode along both axes. This finding was hypothesized to result from the familiarity with the pattern since it resembles cycling behavior. It illustrates how cognitive mapping is superimposed onto the dynamics of interlimb coordination. Overall, these results support the presence of both the egocentric and allocentric constraint during bimanual movement production.

  3. Sagittal balance in adolescent idiopathic scoliosis: radiographic study of spino-pelvic compensation after surgery.

    PubMed

    La Maida, Giovanni Andrea; Zottarelli, Leonardo; Mineo, Giuseppe Vincenzo; Misaggi, Bernardo

    2013-11-01

    Radiographic retrospective study of a consecutive series of 76 patients with adolescent idiopathic scoliosis (AIS) undergoing posterior only surgical correction and fusion. To evaluate the sagittal profile changes in a population of adolescent idiopathic scoliosis after posterior only surgical correction. Although the relationship between pelvic indexes and sagittal profile is well known, little has been published about the sagittal profile changes after posterior surgery in adolescent idiopathic scoliosis. Radiological data of 76 AIS patients were analyzed by an independent observer to compare pelvic indexes and spino-pelvic parameters before and at the last follow-up after surgical posterior correction. All patients underwent a posterior only surgical correction by using different anchor techniques (all screws or hybrid construct), but the same derotation correction maneuver (C-D technique). The collected data were analyzed, on AP and LL radiographic views of the entire spine in the upright position, from the same independent observer and using the same Impax software analysis. We collected for each patient on latero-lateral X-rays the following data: pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), C7 plumb line (C7PL) and spino-sacral angle (SSA). All data were analyzed using a D'Agostino-Pearson normality test and the comparison between the groups was performed with a student's t test. The mean pelvic incidence (PI) of the cohort was 48.89° (± 11.24), with a mean Cobb angle for the main curve of 60.13° (± 13.6). The mean value of residual scoliosis after surgery was 28.18° (± 13.22) with an average improvement of the curve in the frontal plane of 53.2 %. The amount of curve correction of the primary scoliosis curve was statistically significant (p < 0.0001). In the evaluation of the whole group after surgery, we observed an increasing amount of PT (average delta value 2.38°) with a statistical

  4. Standing sagittal alignment of the whole axial skeleton with reference to the gravity line in humans.

    PubMed

    Hasegawa, Kazuhiro; Okamoto, Masashi; Hatsushikano, Shun; Shimoda, Haruka; Ono, Masatoshi; Homma, Takao; Watanabe, Kei

    2017-05-01

    between offset of C7 vertebra from the sagittal vertical axis (a vertical line drawn through the posterior superior corner of the sacrum in the sagittal plane) and age, but no correlation was detected between the centre of the acoustic meati-GL offset and age. Cervical lordosis (CL), pelvic tilt (PT), pelvic incidence, hip extension, knee flexion and ankle dorsiflexion increased significantly with age. Our results revealed that aging induces trunk stooping, but the global alignment is compensated for by an increase in the CL, PT and knee flexion, with the main function of CL and PT to maintain a horizontal gaze in a healthy population. © 2017 The Authors Journal of Anatomy published by John Wiley & Sons Ltd on behalf of Anatomical Society.

  5. Skeletal Stability after Large Mandibular Advancement (> 10 mm) with Bilateral Sagittal Split Osteotomy and Skeletal Elastic Intermaxillary Fixation

    PubMed Central

    Rodrigo-Domingo, Maria; Jensen, Thomas

    2016-01-01

    ABSTRACT Objectives The aim of the present study was to assess the skeletal stability after large mandibular advancement (> 10 mm) with bilateral sagittal split osteotomy and skeletal elastic intermaxillary fixation and to correlate the skeletal stability with the vertical facial type. Material and Methods A total of 33 consecutive patients underwent bimaxillary surgery to correct skeletal Class II malocclusion with a mandibular advancement (> 10 mm) measured at B-point and postoperative skeletal elastic intermaxillary fixation for 16 weeks. Skeletal stability was evaluated using lateral cephalometric radiographs obtained preoperative (T1), 8 weeks postoperatively (T2), and 18 month postoperatively (T3). B-point and pogonion (Pog) was used to measure the skeletal relapse and the mandibular plane angle (MP-angle) was used to determine the vertical facial type. Results The mean advancement from T1 to T2 were 11.6 mm and 13.5 mm at B-point and Pog, respectively. The mean skeletal relapse from T2 to T3 was -1.3 mm at B-point and -1.6 mm at Pog. The nineteen patients characterized as long facial types, showed the highest amount of skeletal relapse (-1.5 mm at B-point and -1.9 mm at Pog). Conclusions The present study showed a limited amount of skeletal relapse in large mandibular advancement (> 10 mm) with bilateral sagittal split osteotomy and skeletal elastic intermaxillary fixation. Bilateral sagittal split osteotomy in combination with skeletal intermaxillary fixation can therefore be an alternative to distraction osteogenesis in large mandibular advancements. PMID:27489609

  6. En bloc control of deep and superficial thoracic muscles in sagittal loading and unloading of the trunk.

    PubMed

    Lee, Linda-Joy; Coppieters, Michel W; Hodges, Paul W

    2011-04-01

    External perturbation of the trunk via sudden loading and unloading is an established method to study control of spinal stability and postural equilibrium. As differential control of the deep and superficial lumbar multifidus occurs during predictable sagittal loading, we hypothesized that the deep and superficial components of the thoracic paraspinal muscles would also be differentially active during loading and unloading of the trunk. Variation in sagittal mobility between regions of the thorax and previous data of differences in control of the thoracic paraspinal muscles between regions in other tasks supported a hypothesis that there would be region-specific differences in responses to loading and unloading. This study used fine-wire electrodes to record electromyographic (EMG) activity from the right deep (multifidus/rotatores) and superficial (longissimus) muscles at T5, T8, and T11 in ten healthy subjects during predictable and unpredictable sudden loading and unloading of the trunk. EMG amplitude was calculated during 10 ms epochs for 50 ms before the onset of trunk perturbation and 150 ms after the perturbation. Contrary to our hypotheses, deep and superficial thoracic paraspinal muscles were similarly active (loading: p=0.470; unloading: p=0.137) and similarly affected by the degree of predictability at all levels. Thus, deep and superficial thoracic paraspinal muscles are recruited en bloc during sagittal plane trunk perturbations. This contrasts previous findings of differential control between the deep and superficial thoracic paraspinal muscles during rotational tasks, and provides evidence that discrete control of thoracic paraspinal muscle fascicles is specific to the direction of forces applied to the trunk. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. LOW-LATITUDE CORONAL HOLES, DECAYING ACTIVE REGIONS, AND GLOBAL CORONAL MAGNETIC STRUCTURE

    SciTech Connect

    Petrie, G. J. D.; Haislmaier, K. J.

    2013-10-01

    We study the relationship between decaying active-region magnetic fields, coronal holes, and the global coronal magnetic structure using Global Oscillations Network Group synoptic magnetograms, Solar TErrestrial RElations Observatory extreme-ultraviolet synoptic maps, and coronal potential-field source-surface models. We analyze 14 decaying regions and associated coronal holes occurring between early 2007 and late 2010, 4 from cycle 23 and 10 from cycle 24. We investigate the relationship between asymmetries in active regions' positive and negative magnetic intensities, asymmetric magnetic decay rates, flux imbalances, global field structure, and coronal hole formation. Whereas new emerging active regions caused changes in the large-scale coronal field, the coronal fields of the 14 decaying active regions only opened under the condition that the global coronal structure remained almost unchanged. This was because the dominant slowly varying, low-order multipoles prevented opposing-polarity fields from opening and the remnant active-region flux preserved the regions' low-order multipole moments long after the regions had decayed. Thus, the polarity of each coronal hole necessarily matched the polar field on the side of the streamer belt where the corresponding active region decayed. For magnetically isolated active regions initially located within the streamer belt, the more intense polarity generally survived to form the hole. For non-isolated regions, flux imbalance and topological asymmetry prompted the opposite to occur in some cases.

  8. Lumbosacral Sagittal Alignment in Association to Intervertebral Disc Diseases

    PubMed Central

    Maleki, Farid; Meybodi, Ali Tayebi; Mahdavi, Ali; Saberi, Hooshang

    2014-01-01

    Study Design A cross-sectional case-control study was designed to compare the sagittal alignment of lumbosacral regions in two groups of patients suffering from low back pain, one with intervertebral disc pathologies and one without. Purpose To evaluate the correlation between lumbosacral sagittal alignment and disc degeneration. Overview of Literature Changes in lumbar lordosis and pelvic parameters in degenerative disc lesions have been assessed in few studies. Overall, patients with discopathy were shown to have lower lumbar lordosis and more vertical sacral profiles. Methods From patients with intractable low back pain undergoing lumbosacral magnetic resonance imaging, 50 subjects with disc degeneration and 50 controls with normal scans were consecutively enrolled. A method was defined with anterior tangent-lines going through anterior bodies of L1 and S1 to measure global lumbosacral angle, incorporating both lumbar lordosis and sacral slope. Global lumbosacral angle using the proposed method and lumbar lordosis using Cobb's method were measured in both groups. Results Lumbar lordosis based on Cobb's method was lower in group with discopathy (20°-67°; mean, 40.48°±9.89°) than control group (30°-62°; mean, 44.96°±7.68°), although it was not statistically significant. The proposed global lumbosacral angle in subject group (53°-103°; mean, 76.5°±11.018°) was less than control group (52°-101°; mean, 80.18°±9.95°), with the difference being statistically significant (p=0.002). Conclusions Patients with intervertebral disc lesions seem to have more straightened lumbosacral profiles, but it has not been proven which comes first: disc degeneration or changes in sagittal alignment. Finding an answer to this dilemma demands more comprehensive long-term prospective studies. PMID:25558325

  9. Comparative Assessment of Sagittal Skeletal Discrepancy: A Cephalometric Study

    PubMed Central

    N., Dilip Kumar; Prasad, Mandav; Shamnur, Naveen; G., Arun Kumar; K.R., Sridhar; B.R., Gopal Krishna; Gupta, Neeraj

    2015-01-01

    Background and Objectives Evaluating the sagittal apical base relationship during orthodontic diagnosis and treatment planning is an important step. This study was aimed at comparison of Beta angle, ANB angle and Wit’s appraisal for assessment of sagittal skeletal discrepancy. Materials and Methods Eighty six young adults (43 female and 43 male) were selected from the patient’s reporting to Department of Orthodontics, College of Dental Sciences, Davangere, India. Family lineage was studied to know the nativity of Davangere. The standardized pre-treatment lateral cephalogram of the chosen sample was traced. The sample was divided into three skeletal pattern groups: Class I, Class II and Class III, based on the ANB angle and profile, Beta angle was assessed in each group. Statistical Analysis The data was subjected to statistical analysis student’s t-test, ANOVA test and correlation and regression analysis, using the software namely SPSS Software version 13. Microsoft word and Excel were used to generate graphs and tables. Results In the local Davangere population, Class I skeletal pattern group exhibited Beta angle between 26°–34°, Beta angle less than 27° was found in Class II skeletal pattern, and Beta angle greater than 32° was seen Class III skeletal pattern. The coefficient of variation of Beta angle in all the three groups was significantly homogenous compared to ANB angle and Wits appraisal. The correlation and regression analysis of the total sample indicated a highly significant correlation between Beta angle and ANB angle (p<.001), and between Beta angle and Wits appraisal (p<.01). Conclusion Beta angle can be used to classify subjects into different skeletal patterns. The Correlation and regression analysis for the total sample suggests a highly significant relation between Beta angle and ANB angle and, between Beta angle and Wits appraisal. It can be more reliably used to assess sagittal jaw discrepancies than ANB angle and Wits appraisal

  10. Comparative assessment of sagittal skeletal discrepancy: a cephalometric study.

    PubMed

    Aparna, P; Kumar, Dilip N; Prasad, Mandav; Shamnur, Naveen; G, Arun Kumar; K R, Sridhar; B R, Gopal Krishna; Gupta, Neeraj

    2015-04-01

    Evaluating the sagittal apical base relationship during orthodontic diagnosis and treatment planning is an important step. This study was aimed at comparison of Beta angle, ANB angle and Wit's appraisal for assessment of sagittal skeletal discrepancy. Eighty six young adults (43 female and 43 male) were selected from the patient's reporting to Departm