[Minimally invasive cement augmentation of osteoporotic vertebral compression fractures with the new radiofrequency kyphoplasty].

PubMed

Mattyasovszky, S G; Kurth, A A; Drees, P; Gemidji, J; Thomczyk, S; Kafchitsas, K

2014-10-01

Minimally invasive cement augmentation of painful osteoporotic vertebral compression fractures in elderly patients. Painful osteoporotic vertebral compression fractures in elderly patients (> 65 years of age) after conservative therapy failure. Painful aggressive primary tumors of the spine or osteolytic metastases to the spine with high risk of vertebral fracture in the palliative care setting. General contraindications for surgical interventions. Local soft-tissue infection. Osteomyelitis, discitis or systemic infection. Coagulopathy refractory to treatment or bleeding diathesis. Asymptomatic vertebral compression fractures. Burst of the posterior vertebral column with high degree of spinal canal stenosis. Primary or metastatic spinal tumors with epidural growth. Prone position on a radiolucent operating table. Fluoroscopic localization of the fractured vertebra using two conventional C-arm devices (anteroposterior and lateral views). Fluoroscopic localization of the fractured vertebra using two conventional C-arm devices (anteroposterior and lateral views). An introducer is inserted through a small skin incision into the pedicle under fluoroscopic guidance. To create a site- and size-specific three-dimensional cavity in the center of the fractured vertebra, the navigational VertecoR™ MidLine Osteotome was inserted through the correctly sited introducer and guided fluoroscopically. As the MidLine Osteotome allows angulation of the tip up to 90° by rotating the handle, a cavity over the midline of the vertebral body can mainly be created through one pedicle. The radiofrequency activated cohesive ultrahigh viscosity PMMA cement (ER(2) bone cement) is injected stepwise on demand by remote control under continuous pressure from the hydraulic assembly into the vertebral body. Bed rest for 6 h postoperatively in supine position. Early mobilization without a corset on the day of surgery. Specific back and abdominal exercises that strengthen the back and abdominal muscles. Pain dependent increase of weight bearing. Continue osteoporosis therapy and start specific drug therapy according to the local guidlines if necessary. In all, 44 patients (29 women, 15 men) with a mean age of 73.5 years with a total of 62 painful osteoporotic vertebral fractures were treated with RF kyphoplasty from May 2009 until July 2010, and followed over a period of 12 months. The mean operating time per patient was 36.2 min, the operating time per vertebra was 25.7 min. All the patients studied experienced an early and persistent significant pain relief even 12 months after therapy (8 ± 1.4 vs. 2.7 ± 1.9) according to the visual analogue pain scale. According to the Oswestry Disability Index (ODI) as a disease-specific disability measure all the patients improved significantly (p < 0.001) in the level of disability after operative treatment (56.2 ± 18.8 vs. 34.5 ± 16.6). Cement leakage was detected in 17 out of 62 (27.4 %) augmented vertebrae, whereas all the patients with cement leakage remained asymptomatic. One patient had subsequent vertebral fractures after a period of 6 months.

[Correlation analysis of cement leakage with volume ratio of intravertebral bone cement to vertebral body and vertebral body wall incompetence in percutaneous vertebroplasty for osteoporotic vertebral compression fractures].

PubMed

Liang, De; Ye, Linqiang; Jiang, Xiaobing; Huang, Weiquan; Yao, Zhensong; Tang, Yongchao; Zhang, Shuncong; Jin, Daxiang

2014-11-01

To investigate the risk factors of cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF). Between March 2011 and March 2012, 98 patients with single level OVCF were treated by PVP, and the clinical data were analyzed retrospectively. There were 13 males and 85 females, with a mean age of 77.2 years (range, 54-95 years). The mean disease duration was 43 days (range, 15-120 days), and the mean T score of bone mineral density (BMD) was -3.8 (range, -6.7- -2.5). Bilateral transpedicular approach was used in all the patients. The patients were divided into cement leakage group and no cement leakage group by occurrence of cement leakage based on postoperative CT. Single factor analysis was used to analyze the difference between 2 groups in T score of BMD, operative level, preoperative anterior compression degree of operative vertebrae, preoperative middle compression degree of operative vertebrae, preoperative sagittal Cobb angle of operative vertebrae, preoperative vertebral body wall incompetence, cement volume, and volume ratio of intravertebral bone cement to vertebral body. All relevant factors were introduced to logistic regression analysis to analyze the risk factors of cement leakage. All procedures were performed successfully. The mean operation time was 40 minutes (range, 30-50 minutes), and the mean volume ratio of intravertebral bone cement to vertebral body was 24.88% (range, 7.84%-38.99%). Back pain was alleviated significantly in all the patients postoperatively. All patients were followed up with a mean time of 8 months (range, 6-12 months). Cement leakage occurred in 49 patients. Single factor analysis showed that there were significant differences in the volume ratio of intravertebral bone cement to vertebral body and preoperative vertebral body wall incompetence between 2 groups (P < 0.05), while no significant difference in T score of BMD, operative level, preoperative anterior compression degree of operative vertebrae, preoperative middle compression degree of operative vertebrae, preoperative sagittal Cobb angle of operative vertebrae, and cement volume (P > 0.05). The logistic regression analysis showed that the volume ratio of intravertebral bone cement to vertebral body (P < 0.05) and vertebral body wall incompetence (P < 0.05) were the risk factors for occurrence of cement leakage. The volume ratio of intravertebral bone cement to vertebral body and vertebral body wall incompetence are risk factors of cement leakage in PVP for OVCF. Cement leakage is easy to occur in operative level with vertebral body wall incompetence and high volume ratio of intravertebral bone cement to vertebral body.

Multilevel thoracic hemangioma with spinal cord compression in a pediatric patient: case report and review of the literature.

PubMed

Cherian, Jacob; Sayama, Christina M; Adesina, Adekunle M; Lam, Sandi K; Luerssen, Thomas G; Jea, Andrew

2014-09-01

Vertebral hemangiomas are common benign vascular tumors of the spine. It is very rare for these lesions to symptomatically compress neural elements. If spinal cord compression does occur, it usually involves only a single level. Multilevel vertebral hemangiomas causing symptomatic spinal cord compression have never been reported in the pediatric population to the best of our knowledge. We report the case of a 15-year-old boy presenting with progressive paraparesis due to thoracic spinal cord compression from a multilevel thoracic hemangioma (T5-T10) with epidural extension. Because of his progressive neurological deficit, he was initially treated with urgent multilevel decompressive laminectomies from T4 to T11. This was to be followed by radiotherapy for residual tumor, but the patient was unfortunately lost to follow-up. He re-presented 3 years later with recurrent paraparesis and progressive disease. This was treated with urgent radiotherapy with good response. As of 6 months follow-up, he has made an excellent neurological recovery. In this report, we present the first case of a child with multilevel vertebral hemangiomas causing symptomatic spinal cord compression and review the literature to detail the pathophysiology, management, and treatment of other cases of spinal cord compression by vertebral hemangiomas.

Vertebral Augmentation Involving Vertebroplasty or Kyphoplasty for Cancer-Related Vertebral Compression Fractures: An Economic Analysis.

PubMed

2016-01-01

Untreated vertebral compression fractures can have serious clinical consequences and impose a considerable impact on patients' quality of life and on caregivers. Since non-surgical management of these fractures has limited effectiveness, vertebral augmentation procedures are gaining acceptance in clinical practice for pain control and fracture stabilization. The objective of this analysis was to determine the cost-effectiveness and budgetary impact of kyphoplasty or vertebroplasty compared with non-surgical management for the treatment of vertebral compression fractures in patients with cancer. We performed a systematic review of health economic studies to identify relevant studies that compare the cost-effectiveness of kyphoplasty or vertebroplasty with non-surgical management for the treatment of vertebral compression fractures in adults with cancer. We also performed a primary cost-effectiveness analysis to assess the clinical benefits and costs of kyphoplasty or vertebroplasty compared with non-surgical management in the same population. We developed a Markov model to forecast benefits and harms of treatments, and corresponding quality-adjusted life years and costs. Clinical data and utility data were derived from published sources, while costing data were derived using Ontario administrative sources. We performed sensitivity analyses to examine the robustness of the results. In addition, a 1-year budget impact analysis was performed using data from Ontario administrative sources. Two scenarios were explored: (a) an increase in the total number of vertebral augmentation procedures performed among patients with cancer in Ontario, maintaining the current proportion of kyphoplasty versus vertebroplasty; and (b) no increase in the total number of vertebral augmentation procedures performed among patients with cancer in Ontario but an increase in the proportion of kyphoplasties versus vertebroplasties. The base case considered each of kyphoplasty and vertebroplasty versus non-surgical management. Kyphoplasty and vertebroplasty were associated with an incremental cost-effectiveness ratio of $33,471 and $17,870, respectively, per quality-adjusted life-year gained. The budgetary impact of funding vertebral augmentation procedures for the treatment of vertebral compression fractures in adults with cancer in Ontario was estimated at about $2.5 million in fiscal year 2014/15. More widespread use of vertebral augmentation procedures raised total expenditures under a number of scenarios, with costs increasing by $67,302 to $913,386. Our findings suggest that the use of kyphoplasty or vertebroplasty in the management of vertebral compression fractures in patients with cancer may be a cost-effective strategy at commonly accepted willingness-to-pay thresholds. Nonetheless, more widespread use of kyphoplasty (and vertebroplasty to a lesser extent) would likely be associated with net increases in health care costs.

One-stage posterior instrumentation surgery for the treatment of osteoporotic vertebral collapse with neurological deficits

PubMed Central

Ito, Manabu; Abumi, Kuniyoshi; Kotani, Yoshihisa; Takahata, Masahiko; Hojo, Yoshihiro; Minami, Akio

2010-01-01

The number of reports describing osteoporotic vertebral fracture has increased as the number of elderly people has grown. Anterior decompression and fusion alone for the treatment of vertebral collapse is not easy for patients with comorbid medical problems and severe bone fragility. The purpose of the present study was to evaluate the efficacy of one-stage posterior instrumentation surgery for the treatment of osteoporotic vertebral collapse with neurological deficits. A consecutive series of 21 patients who sustained osteoporotic vertebral collapse with neurological deficits were managed with posterior decompression and short-segmental pedicle screw instrumentation augmented with ultra-high molecular weight polyethylene (UHMWP) cables with or without vertebroplasty using calcium phosphate cement. The mean follow-up was 42 months. All patients showed neurologic recovery. Segmental kyphotic angle at the instrumented level was significantly improved from an average preoperative kyphosis of 22.8–14.7 at a final follow-up. Spinal canal occupation was significantly reduced from an average before surgery of 40.4–19.1% at the final follow-up. Two patients experienced loosening of pedicle screws and three patients developed subsequent vertebral compression fractures within adjacent segments. However, these patients were effectively treated in a conservative fashion without any additional surgery. Our results indicated that one-stage posterior instrumentation surgery augmented with UHMWP cables could provide significant neurological improvement in the treatment of osteoporotic vertebral collapse. PMID:20157741

One-stage posterior instrumentation surgery for the treatment of osteoporotic vertebral collapse with neurological deficits.

PubMed

Sudo, Hideki; Ito, Manabu; Abumi, Kuniyoshi; Kotani, Yoshihisa; Takahata, Masahiko; Hojo, Yoshihiro; Minami, Akio

2010-06-01

The number of reports describing osteoporotic vertebral fracture has increased as the number of elderly people has grown. Anterior decompression and fusion alone for the treatment of vertebral collapse is not easy for patients with comorbid medical problems and severe bone fragility. The purpose of the present study was to evaluate the efficacy of one-stage posterior instrumentation surgery for the treatment of osteoporotic vertebral collapse with neurological deficits. A consecutive series of 21 patients who sustained osteoporotic vertebral collapse with neurological deficits were managed with posterior decompression and short-segmental pedicle screw instrumentation augmented with ultra-high molecular weight polyethylene (UHMWP) cables with or without vertebroplasty using calcium phosphate cement. The mean follow-up was 42 months. All patients showed neurologic recovery. Segmental kyphotic angle at the instrumented level was significantly improved from an average preoperative kyphosis of 22.8-14.7 at a final follow-up. Spinal canal occupation was significantly reduced from an average before surgery of 40.4-19.1% at the final follow-up. Two patients experienced loosening of pedicle screws and three patients developed subsequent vertebral compression fractures within adjacent segments. However, these patients were effectively treated in a conservative fashion without any additional surgery. Our results indicated that one-stage posterior instrumentation surgery augmented with UHMWP cables could provide significant neurological improvement in the treatment of osteoporotic vertebral collapse.

Fatal fat embolism in isolated vertebral compression fracture

PubMed Central

Saldanha, Vilas; Balasubramanian, Manjula; Handal, John

2010-01-01

Fat embolism after long bone and pelvic fractures as well as orthopedic interventions is a well-documented phenomenon, but it is highly unusual after isolated vertebral fractures. We report a case of fatal fat embolism in a 78-year-old man after an isolated vertebral compression fracture with no related orthopedic intervention. A high index of suspicion is necessary for early diagnosis and successfully treating this unusual complication. PMID:20229119

Fatal fat embolism in isolated vertebral compression fracture.

PubMed

Lastra, Ricardo R; Saldanha, Vilas; Balasubramanian, Manjula; Handal, John

2010-07-01

Fat embolism after long bone and pelvic fractures as well as orthopedic interventions is a well-documented phenomenon, but it is highly unusual after isolated vertebral fractures. We report a case of fatal fat embolism in a 78-year-old man after an isolated vertebral compression fracture with no related orthopedic intervention. A high index of suspicion is necessary for early diagnosis and successfully treating this unusual complication.

Lumbar hemangioma masking a plasma cell tumor--case report and review of the literature.

PubMed

Haque, Maahir U; Wilson, Adam N; Blecher, Haim D; Reich, Steven M

2013-08-01

Vertebral hemangiomata are ubiquitous bone tumors. Often multiple, they are generally benign in nature and slow growing. They typically have a predictable radiographic appearance. Occasionally, hemangiomata may behave in a more aggressive manner, causing pathologic fracture or even symptoms/signs of nerve compression. In such cases, one must be careful not to assume that an atypical hemangioma is responsible. Coexisting, more malignant processes may be present and sometimes may be radiographically undetectable in the setting of acute fracture. This was the case in our patient. Case report/university spine surgery center. The patient underwent a corpectomy of her affected vertebra with conversion to a total spondylectomy when intraoperative frozen section was consistent with plasma cell neoplasm. A reconstruction with vertebral body replacement and fusion through anterior and posterior approaches was completed. Subsequently, the literature was reviewed for other cases of atypical hemangiomata to investigate the incidence of coexistent lesions. This patient presented with pain secondary to an unstable pathologic vertebral body fracture. Surgery to stabilize her spine was elected. Intraoperative recognition of abnormal-appearing tissue led to the diagnosis of a plasma cell neoplasm that was not seen on imaging. Coexistent in the same vertebra was hemangiomatous tissue that was visible on preoperative imaging. There are rare reports of aggressively behaving hemangiomata that mainly have occurred in the thoracic spine. There have been no reports of the coexistence of a hemangioma and a plasma cell tumor in the same vertebral level in the setting of acute compression fracture. Copyright © 2013 Elsevier Inc. All rights reserved.

Vertebral Augmentation Involving Vertebroplasty or Kyphoplasty for Cancer-Related Vertebral Compression Fractures: A Systematic Review

PubMed Central

Pron, Gaylene; Holubowich, Corinne; Kaulback, Kellee

2016-01-01

Background Cancers that metastasize to the spine and primary cancers such as multiple myeloma can result in vertebral compression fractures or instability. Conservative strategies, including bed rest, bracing, and analgesic use, can be ineffective, resulting in continued pain and progressive functional disability limiting mobility and self-care. Surgery is not usually an option for cancer patients in advanced disease states because of their poor medical health or functional status and limited life expectancy. The objectives of this review were to evaluate the effectiveness and safety of percutaneous image-guided vertebral augmentation techniques, vertebroplasty and kyphoplasty, for palliation of cancer-related vertebral compression fractures. Methods We performed a systematic literature search for studies on vertebral augmentation of cancer-related vertebral compression fractures published from January 1, 2000, to October 2014; abstracts were screened by a single reviewer. For those studies meeting the eligibility criteria, full-text articles were obtained. Owing to the heterogeneity of the clinical reports, we performed a narrative synthesis based on an analytical framework constructed for the type of cancer-related vertebral fractures and the diversity of the vertebral augmentation interventions. Results The evidence review identified 3,391 citations, of which 111 clinical reports (4,235 patients) evaluated the effectiveness of vertebroplasty (78 reports, 2,545 patients) or kyphoplasty (33 reports, 1,690 patients) for patients with mixed primary spinal metastatic cancers, multiple myeloma, or hemangiomas. Overall the mean pain intensity scores often reported within 48 hours of vertebral augmentation (kyphoplasty or vertebroplasty), were significantly reduced. Analgesic use, although variably reported, usually involved parallel decreases, particularly in opioids, and mean pain-related disability scores were also significantly improved. In a randomized controlled trial comparing kyphoplasty with usual care, improvements in pain scores, pain-related disability, and health-related quality of life were significantly better in the kyphoplasty group than in the usual care group. Bone cement leakage, mostly asymptomatic, was commonly reported after vertebroplasty and kyphoplasty. Major adverse events, however, were uncommon. Conclusions Both vertebroplasty and kyphoplasty significantly and rapidly reduced pain intensity in cancer patients with vertebral compression fractures. The procedures also significantly decreased the need for opioid pain medication, and functional disabilities related to back and neck pain. Pain palliative improvements and low complication rates were consistent across the various cancer populations and vertebral fractures that were investigated. PMID:27298655

Vertebral Augmentation Involving Vertebroplasty or Kyphoplasty for Cancer-Related Vertebral Compression Fractures: A Systematic Review.

PubMed

2016-01-01

Cancers that metastasize to the spine and primary cancers such as multiple myeloma can result in vertebral compression fractures or instability. Conservative strategies, including bed rest, bracing, and analgesic use, can be ineffective, resulting in continued pain and progressive functional disability limiting mobility and self-care. Surgery is not usually an option for cancer patients in advanced disease states because of their poor medical health or functional status and limited life expectancy. The objectives of this review were to evaluate the effectiveness and safety of percutaneous image-guided vertebral augmentation techniques, vertebroplasty and kyphoplasty, for palliation of cancer-related vertebral compression fractures. We performed a systematic literature search for studies on vertebral augmentation of cancer-related vertebral compression fractures published from January 1, 2000, to October 2014; abstracts were screened by a single reviewer. For those studies meeting the eligibility criteria, full-text articles were obtained. Owing to the heterogeneity of the clinical reports, we performed a narrative synthesis based on an analytical framework constructed for the type of cancer-related vertebral fractures and the diversity of the vertebral augmentation interventions. The evidence review identified 3,391 citations, of which 111 clinical reports (4,235 patients) evaluated the effectiveness of vertebroplasty (78 reports, 2,545 patients) or kyphoplasty (33 reports, 1,690 patients) for patients with mixed primary spinal metastatic cancers, multiple myeloma, or hemangiomas. Overall the mean pain intensity scores often reported within 48 hours of vertebral augmentation (kyphoplasty or vertebroplasty), were significantly reduced. Analgesic use, although variably reported, usually involved parallel decreases, particularly in opioids, and mean pain-related disability scores were also significantly improved. In a randomized controlled trial comparing kyphoplasty with usual care, improvements in pain scores, pain-related disability, and health-related quality of life were significantly better in the kyphoplasty group than in the usual care group. Bone cement leakage, mostly asymptomatic, was commonly reported after vertebroplasty and kyphoplasty. Major adverse events, however, were uncommon. Both vertebroplasty and kyphoplasty significantly and rapidly reduced pain intensity in cancer patients with vertebral compression fractures. The procedures also significantly decreased the need for opioid pain medication, and functional disabilities related to back and neck pain. Pain palliative improvements and low complication rates were consistent across the various cancer populations and vertebral fractures that were investigated.

Vertebral osteomyelitis and epidural abscess caused by gas gangrene presenting with complete paraplegia: a case report.

PubMed

Akagawa, Manabu; Kobayashi, Takashi; Miyakoshi, Naohisa; Abe, Eiji; Abe, Toshiki; Kikuchi, Kazuma; Shimada, Yoichi

2015-04-11

Gas gangrene is most often caused by Clostridium perfringens infection. Gas gangrene is a medical emergency that develops suddenly. The mortality rate is higher with trunk involvement than with involvement of the extremities, which carries a better prognosis. With respect to vertebral involvement, there are few reports in the literature. The purpose of this paper is to report a very rare case of vertebral osteomyelitis caused by gas gangrene. A 78-year-old Japanese woman with diabetes mellitus was admitted to our hospital with the chief complaints of back pain, dysuria, and complete paralysis of both legs. A computed tomography scan showed soft tissue swelling anterolaterally at intervertebral disc level T11/12 and a gas-containing epidural abscess that compressed her spinal cord. Cultures later grew Clostridium perfringens and Escherichia coli. Hemilaminectomy was done from T10 to T12, and an epidural abscess was removed. She went on to have fusion surgery 6 weeks after the initial operation and subsequently experienced complete pain relief. She was discharged 2 months later, at which time she was able to walk with a cane. Examination 18 months after surgery showed normal gait without a cane. Discitis caused by gas gangrene infection was successfully treated by immediate debridement and subsequent fusion surgery.

Lumbar vertebral haemangioma causing pathological fracture, epidural haemorrhage, and cord compression: a case report and review of literature.

PubMed

Vinay, S; Khan, S K; Braybrooke, J R

2011-01-01

Vertebral haemangiomas are recognized to be one of the commonest benign tumours of the vertebral column, occurring mostly in the thoracic spine. The vast majority of these are asymptomatic. Infrequently, these can turn symptomatic and cause neurological deficit (cord compression) through any of four reported mechanisms: (1) epidural extension; (2) expansion of the involved vertebra(e) causing spinal canal stenosis; (3) spontaneous epidural haemorrhage; (4) pathological burst fracture. Thoracic haemangiomas have been reported to be more likely to produce cord compression than lumbar haemangiomas. A forty-nine year old male with acute onset spinal cord compression from a pathological fracture in a first lumbar vertebral haemangioma. An MRI delineated the haemangioma and extent of bleeding that caused the cord compression. These were confirmed during surgery and the haematoma was evacuated. The spine was instrumented from T12 to L2, and a cement vertebroplasty was performed intra-operatively. Written consent for publication was obtained from the patient. The junctional location of the first lumbar vertebra, and the structural weakness from normal bone being replaced by the haemangioma, probably caused it to fracture under axial loading. This pathological fracture caused bleeding from the vascularized bone, resulting in cord compression.

Lumbar vertebral haemangioma causing pathological fracture, epidural haemorrhage, and cord compression: a case report and review of literature

PubMed Central

Vinay, S; Khan, SK; Braybrooke, JR

2011-01-01

Context Vertebral haemangiomas are recognized to be one of the commonest benign tumours of the vertebral column, occurring mostly in the thoracic spine. The vast majority of these are asymptomatic. Infrequently, these can turn symptomatic and cause neurological deficit (cord compression) through any of four reported mechanisms: (1) epidural extension; (2) expansion of the involved vertebra(e) causing spinal canal stenosis; (3) spontaneous epidural haemorrhage; (4) pathological burst fracture. Thoracic haemangiomas have been reported to be more likely to produce cord compression than lumbar haemangiomas. Findings A forty-nine year old male with acute onset spinal cord compression from a pathological fracture in a first lumbar vertebral haemangioma. An MRI delineated the haemangioma and extent of bleeding that caused the cord compression. These were confirmed during surgery and the haematoma was evacuated. The spine was instrumented from T12 to L2, and a cement vertebroplasty was performed intra-operatively. Written consent for publication was obtained from the patient. Clinical Relevance The junctional location of the first lumbar vertebra, and the structural weakness from normal bone being replaced by the haemangioma, probably caused it to fracture under axial loading. This pathological fracture caused bleeding from the vascularized bone, resulting in cord compression. PMID:21756575

Vertebral Augmentation Involving Vertebroplasty or Kyphoplasty for Cancer-Related Vertebral Compression Fractures: An Economic Analysis

PubMed Central

2016-01-01

Background Untreated vertebral compression fractures can have serious clinical consequences and impose a considerable impact on patients' quality of life and on caregivers. Since non-surgical management of these fractures has limited effectiveness, vertebral augmentation procedures are gaining acceptance in clinical practice for pain control and fracture stabilization. The objective of this analysis was to determine the cost-effectiveness and budgetary impact of kyphoplasty or vertebroplasty compared with non-surgical management for the treatment of vertebral compression fractures in patients with cancer. Methods We performed a systematic review of health economic studies to identify relevant studies that compare the cost-effectiveness of kyphoplasty or vertebroplasty with non-surgical management for the treatment of vertebral compression fractures in adults with cancer. We also performed a primary cost-effectiveness analysis to assess the clinical benefits and costs of kyphoplasty or vertebroplasty compared with non-surgical management in the same population. We developed a Markov model to forecast benefits and harms of treatments, and corresponding quality-adjusted life years and costs. Clinical data and utility data were derived from published sources, while costing data were derived using Ontario administrative sources. We performed sensitivity analyses to examine the robustness of the results. In addition, a 1-year budget impact analysis was performed using data from Ontario administrative sources. Two scenarios were explored: (a) an increase in the total number of vertebral augmentation procedures performed among patients with cancer in Ontario, maintaining the current proportion of kyphoplasty versus vertebroplasty; and (b) no increase in the total number of vertebral augmentation procedures performed among patients with cancer in Ontario but an increase in the proportion of kyphoplasties versus vertebroplasties. Results The base case considered each of kyphoplasty and vertebroplasty versus non-surgical management. Kyphoplasty and vertebroplasty were associated with an incremental cost-effectiveness ratio of $33,471 and $17,870, respectively, per quality-adjusted life-year gained. The budgetary impact of funding vertebral augmentation procedures for the treatment of vertebral compression fractures in adults with cancer in Ontario was estimated at about $2.5 million in fiscal year 2014/15. More widespread use of vertebral augmentation procedures raised total expenditures under a number of scenarios, with costs increasing by $67,302 to $913,386. Conclusions Our findings suggest that the use of kyphoplasty or vertebroplasty in the management of vertebral compression fractures in patients with cancer may be a cost-effective strategy at commonly accepted willingness-to-pay thresholds. Nonetheless, more widespread use of kyphoplasty (and vertebroplasty to a lesser extent) would likely be associated with net increases in health care costs. PMID:27293494

The impact of posture and prolonged cyclic compressive loading on vertebral joint mechanics.

PubMed

Gooyers, Chad E; McMillan, Robert D; Howarth, Samuel J; Callaghan, Jack P

2012-08-01

An in vitro biomechanics investigation exposing porcine functional spinal units (FSUs) to submaximal cyclic or static compressive forces while in a flexed, neutral, or extended posture. To investigate the combined effect of cyclically applied compressive force (e.g., vibration) and postural deviation on intervertebral joint mechanics. Independently, prolonged vibration exposure and non-neutral postures are known risk factors for development of low back pain and injury. However, there is limited basic scientific evidence to explain how the risk of low back injury from vibration exposure is modified by other mechanical factors. This work examined the influence of static postural deviation on vertebral joint height loss and compressive stiffness under cyclically applied compressive force. Forty-eight FSUs, consisting of 2 adjacent vertebrae, ligaments, and the intervening intervertebral disc were included in the study. Each specimen was randomized to 1 of 3 experimental posture conditions (neutral, flexed, or extended) and assigned to 1 of 2 loading protocols, consisting of (1) cyclic (1500 ± 1200 N applied at 5 Hz using a sinusoidal waveform, resulting in 0.2 g rms acceleration) or (2) 1500 N of static compressive force. RESULTS.: As expected, FSU height loss followed a typical first-order response in both the static and cyclic loading protocols, with the majority (~50%) of the loss occurring in the first 20 minutes of testing. A significant interaction between posture and loading protocol (P < 0.001) was noted in the magnitude of FSU height loss. Subsequent analysis of simple effects revealed significant differences between cyclic and static loading protocols in both a neutral (P = 0.016) and a flexed posture (P < 0.0001). No significant differences (P = 0.320) were noted between pre/postmeasurements of FSU compressive stiffness. Posture is an important mechanical factor to consider when assessing the risk of injury from cyclic loading to the lumbar spine.

An aggressive vertebral hemangioma in pregnancy: a case report.

PubMed

Slimani, Ouafae; Jayi, Sofia; Fdili Alaoui, Fatimazahra; Bouguern, Hakima; Chaara, Hekmat; Fikri, Ghizlane; Alaoui Rachidi, Siham; Sqalli Houssaini, Nadia; Himmich, Mariam; Abdelilah Melhouf, Moulay

2014-06-18

Pregnancy-related compressive myelopathy secondary to vertebral hemangioma is a rare occurrence and its treatment antepartum is rare. A 19-year-old North African woman in her 38th week of pregnancy presented with paraplegia that progressed within 2 days after a rapidly progressive weakness of her lower limbs. Magnetic resonance imaging studies showed compression of her spinal cord in front of the fourth thoracic vertebra for suspected tuberculous spondylitis. A Caesarean section was done followed by corpectomy with a bone graft because we intraoperatively discovered a vertebral hemangioma. Pathology showed an aggressive hemangioma. At any term of pregnancy, extensive neurological involvement which is rapidly progressive due to compression should be considered for immediate decompression.

Compression fractures of the back

MedlinePlus

... treatments. Surgery can include: Balloon kyphoplasty Vertebroplasty Spinal fusion Other surgery may be done to remove bone ... Alternative Names Vertebral compression fractures; Osteoporosis - compression fracture Images Compression fracture References Cosman F, de Beur SJ, ...

Morphological changes of the caudal cervical intervertebral foramina due to flexion-extension and compression-traction movements in the canine cervical vertebral column.

PubMed

Ramos, Renato M; da Costa, Ronaldo C; Oliveira, Andre L A; Kodigudla, Manoj K; Goel, Vijay K

2015-08-06

Previous studies in humans have reported that the dimensions of the intervertebral foramina change significantly with movement of the spine. Cervical spondylomyelopathy (CSM) in dogs is characterized by dynamic and static compressions of the neural components, leading to variable degrees of neurologic deficits and neck pain. Studies suggest that intervertebral foraminal stenosis has implications in the pathogenesis of CSM. The dimensions of the cervical intervertebral foramina may significantly change during neck movements. This could have implication in the pathogenesis of CSM and other diseases associated with radiculopathy such as intervertebral disc disease. The purpose of this study was to quantify the morphological changes in the intervertebral foramina of dogs during flexion, extension, traction, and compression of the canine cervical vertebral column. All vertebral columns were examined with magnetic resonance imaging prior to biomechanic testing. Eight normal vertebral columns were placed in Group 1 and eight vertebral columns with intervertebral disc degeneration or/and protrusion were assigned to Group 2. Molds of the left and right intervertebral foramina from C4-5, C5-6 and C6-7 were taken during all positions and loading modes. Molds were frozen and vertical (height) and horizontal (width) dimensions of the foramina were measured. Comparisons were made between neutral to flexion and extension, flexion to extension, and traction to compression in neutral position. Extension decreased all the foraminal dimensions significantly, whereas flexion increased all the foraminal dimensions significantly. Compression decreased all the foraminal dimensions significantly, and traction increased the foraminal height, but did not significantly change the foraminal width. No differences in measurements were seen between groups. Our results show movement-related changes in the dimensions of the intervertebral foramina, with significant foraminal narrowing in extension and compression.

An aggressive vertebral hemangioma in pregnancy: a case report

PubMed Central

2014-01-01

Introduction Pregnancy-related compressive myelopathy secondary to vertebral hemangioma is a rare occurrence and its treatment antepartum is rare. Case presentation A 19-year-old North African woman in her 38th week of pregnancy presented with paraplegia that progressed within 2 days after a rapidly progressive weakness of her lower limbs. Magnetic resonance imaging studies showed compression of her spinal cord in front of the fourth thoracic vertebra for suspected tuberculous spondylitis. A Caesarean section was done followed by corpectomy with a bone graft because we intraoperatively discovered a vertebral hemangioma. Pathology showed an aggressive hemangioma. Conclusion At any term of pregnancy, extensive neurological involvement which is rapidly progressive due to compression should be considered for immediate decompression. PMID:24943121

Rapid onset aggressive vertebral haemangioma.

PubMed

Cheung, Nicholas K; Doorenbosch, Xenia; Christie, John G

2011-03-01

Vertebral haemangiomas are generally benign asymptomatic vascular tumours seen commonly in the adult population. Presentations in paediatric populations are extremely rare, which can result in rapid onset of neurological symptoms. We present a highly unusual case of an aggressive paediatric vertebral haemangioma causing significant cord compression. A 13-year-old boy presented with only 2 weeks duration of progressive gait disturbance, truncal ataxia and loss of bladder control. Magnetic resonance imaging (MRI) of the spine revealed a large vascular epidural mass extending between T6 and T8 vertebral bodies. Associated displacement and compression of the spinal cord was present. A highly vascular bony lesion was found during surgery. Histopathology identified this tumour to be a vertebral haemangioma. We present an extremely unusual acute presentation of a paediatric vertebral haemangioma. This study highlights the need for early diagnosis, MRI for investigation and urgent surgical management. © Springer-Verlag 2011

Cement Leakage in Percutaneous Vertebral Augmentation for Osteoporotic Vertebral Compression Fractures: Analysis of Risk Factors.

PubMed

Xie, Weixing; Jin, Daxiang; Ma, Hui; Ding, Jinyong; Xu, Jixi; Zhang, Shuncong; Liang, De

2016-05-01

The risk factors for cement leakage were retrospectively reviewed in 192 patients who underwent percutaneous vertebral augmentation (PVA). To discuss the factors related to the cement leakage in PVA procedure for the treatment of osteoporotic vertebral compression fractures. PVA is widely applied for the treatment of osteoporotic vertebral fractures. Cement leakage is a major complication of this procedure. The risk factors for cement leakage were controversial. A retrospective review of 192 patients who underwent PVA was conducted. The following data were recorded: age, sex, bone density, number of fractured vertebrae before surgery, number of treated vertebrae, severity of the treated vertebrae, operative approach, volume of injected bone cement, preoperative vertebral compression ratio, preoperative local kyphosis angle, intraosseous clefts, preoperative vertebral cortical bone defect, and ratio and type of cement leakage. To study the correlation between each factor and cement leakage ratio, bivariate regression analysis was employed to perform univariate analysis, whereas multivariate linear regression analysis was employed to perform multivariate analysis. The study included 192 patients (282 treated vertebrae), and cement leakage occurred in 100 vertebrae (35.46%). The vertebrae with preoperative cortical bone defects generally exhibited higher cement leakage ratio, and the leakage is typically type C. Vertebrae with intact cortical bones before the procedure tend to experience type S leakage. Univariate analysis showed that patient age, bone density, number of fractured vertebrae before surgery, and vertebral cortical bone were associated with cement leakage ratio (P<0.05). Multivariate analysis showed that the main factors influencing bone cement leakage are bone density and vertebral cortical bone defect, with standardized partial regression coefficients of -0.085 and 0.144, respectively. High bone density and vertebral cortical bone defect are independent risk factors associated with bone cement leakage.

Polymethylmethacrylate distribution is associated with recompression after vertebroplasty or kyphoplasty for osteoporotic vertebral compression fractures: A retrospective study.

PubMed

Hou, Yu; Yao, Qi; Zhang, Genai; Ding, Lixiang; Huang, Hui

2018-01-01

Osteoporotic vertebral compression fracture, always accompanied with pain and height loss of vertebral body, has a significant negative impact on life quality of patients. Vertebroplasty or kyphoplasty is minimal invasive techniques to reconstruct the vertebral height and prevent further collapse of the fractured vertebrae by injecting polymethylmethacrylate into vertebral body. However, recompression of polymethylmethacrylate augmented vertebrae with significant vertebral height loss and aggressive local kyphotic was observed frequently after VP or KP. The purpose of this study was to investigate the effect of polymethylmethacrylate distribution on recompression of the vertebral body after vertebroplasty or kyphoplasty surgery for osteoporotic vertebral compression fracture. A total of 281 patients who were diagnosed with vertebral compression fracture (T5-L5) from June 2014 to June 2016 and underwent vertebroplasty or kyphoplasty by polymethylmethacrylate were retrospectively analyzed. The X-ray films at 1 day and 12 months after surgery were compared to evaluate the recompression of operated vertebral body. Patients were divided into those without recompression (non-recompression group) and those with recompression (recompression group). Polymethylmethacrylate distribution pattern, including location and relationship to endplates, was compared between the two groups by lateral X-ray film. Multivariate logistic regression analysis was performed to assess the potential risk factors associated with polymethylmethacrylate distribution for recompression. One hundred and six (37.7%) patients experienced recompression after surgery during the follow-up period. The polymethylmethacrylate distributed in the middle of vertebral body showed significant differences between two groups. In non-recompression group, the polymethylmethacrylate in the middle portion of vertebral body were closer to endplates than that in the recompression group (upper: t = 31.41, p<0.001; lower: t = 12.19, p<0.001). The higher percentage of the height of polymethylmethacrylate in the middle portion of vertebral body indicates the lower risk of recompression (odds ratio [OR]<0.01, p<0.001). The recompression group and non-recompression group showed significant difference in "contacted" polymethylmethacrylate distribution pattern (polymethylmethacrylate contacted to the both upper/lower endplates) (χ2 = 66.23, p<0.001). The vertebra with a "contacted" polymethylmethacrylate distribution pattern has lower risk of recompression (OR = 0.09, p<0.001). Either more polymethylmethacrylate in the middle portion of vertebral body or "contacted" polymethylmethacrylate distribution pattern had a significantly less incidence of recompression. The findings indicated that the control of polymethylmethacrylate distribution during surgery may reduce the risks of recompression after vertebroplasty or kyphoplasty.

Polymethylmethacrylate distribution is associated with recompression after vertebroplasty or kyphoplasty for osteoporotic vertebral compression fractures: A retrospective study

PubMed Central

Yao, Qi; Zhang, Genai; Ding, Lixiang; Huang, Hui

2018-01-01

Background Osteoporotic vertebral compression fracture, always accompanied with pain and height loss of vertebral body, has a significant negative impact on life quality of patients. Vertebroplasty or kyphoplasty is minimal invasive techniques to reconstruct the vertebral height and prevent further collapse of the fractured vertebrae by injecting polymethylmethacrylate into vertebral body. However, recompression of polymethylmethacrylate augmented vertebrae with significant vertebral height loss and aggressive local kyphotic was observed frequently after VP or KP. The purpose of this study was to investigate the effect of polymethylmethacrylate distribution on recompression of the vertebral body after vertebroplasty or kyphoplasty surgery for osteoporotic vertebral compression fracture. Methods A total of 281 patients who were diagnosed with vertebral compression fracture (T5-L5) from June 2014 to June 2016 and underwent vertebroplasty or kyphoplasty by polymethylmethacrylate were retrospectively analyzed. The X-ray films at 1 day and 12 months after surgery were compared to evaluate the recompression of operated vertebral body. Patients were divided into those without recompression (non-recompression group) and those with recompression (recompression group). Polymethylmethacrylate distribution pattern, including location and relationship to endplates, was compared between the two groups by lateral X-ray film. Multivariate logistic regression analysis was performed to assess the potential risk factors associated with polymethylmethacrylate distribution for recompression. Results One hundred and six (37.7%) patients experienced recompression after surgery during the follow-up period. The polymethylmethacrylate distributed in the middle of vertebral body showed significant differences between two groups. In non-recompression group, the polymethylmethacrylate in the middle portion of vertebral body were closer to endplates than that in the recompression group (upper: t = 31.41, p<0.001; lower: t = 12.19, p<0.001). The higher percentage of the height of polymethylmethacrylate in the middle portion of vertebral body indicates the lower risk of recompression (odds ratio [OR]<0.01, p<0.001). The recompression group and non-recompression group showed significant difference in “contacted” polymethylmethacrylate distribution pattern (polymethylmethacrylate contacted to the both upper/lower endplates) (χ2 = 66.23, p<0.001). The vertebra with a “contacted” polymethylmethacrylate distribution pattern has lower risk of recompression (OR = 0.09, p<0.001). Conclusions Either more polymethylmethacrylate in the middle portion of vertebral body or “contacted” polymethylmethacrylate distribution pattern had a significantly less incidence of recompression. The findings indicated that the control of polymethylmethacrylate distribution during surgery may reduce the risks of recompression after vertebroplasty or kyphoplasty. PMID:29856859

Successful Treatment with Microvascular Decompression Surgery of a Patient with Hemiparesis Caused by Vertebral Artery Compression of the Medulla Oblongata: Case Report and Review of the Literature.

PubMed

Ren, Jibin; Sun, Hongtao; Diao, Yunfeng; Niu, Xuegang; Wang, Hang; Wei, Zhengjun; Yuan, Fei

2017-12-01

There are few reports on hemiparesis caused by vascular medullary compression, which can occur because of dolichoectasia of the vertebrobasilar arterial system. In this article, we report a case of vertebral artery compression of the medulla oblongata in a 67-year-old woman. The patient was hypertensive, and she developed hemiparesis and intermittent spasms over 5 years. These spasms had worsened during the last year. Cranial nerve magnetic resonance imaging showed compression of the medulla oblongata by the left vertebral artery. A motor evoked potential (MEP) examination showed abnormal conduction of MEPs of bilateral toe abductors. The patient underwent microvascular decompression surgery under general anesthesia through a retrosigmoid keyhole approach. This operation led to relief of vascular compression and symptomatic improvement. Our case suggests that detailed history, imaging studies, and electrophysiologic studies help lead to a correct and early diagnosis of hemiparesis caused by vascular compression of the rostral ventrolateral medulla. Microvascular decompression surgery improves patient symptoms, and intraoperative electrophysiologic monitoring helps to avoid injury to important adjacent nerves. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnosis and Treatment of Bone Disease in Multiple Myeloma: Spotlight on Spinal Involvement

PubMed Central

Tosi, Patrizia

2013-01-01

Bone disease is observed in almost 80% of newly diagnosed symptomatic multiple myeloma patients, and spine is the bone site that is more frequently affected by myeloma-induced osteoporosis, osteolyses, or compression fractures. In almost 20% of the cases, spinal cord compression may occur; diagnosis and treatment must be carried out rapidly in order to avoid a permanent sensitive or motor defect. Although whole body skeletal X-ray is considered mandatory for multiple myeloma staging, magnetic resonance imaging is presently considered the most appropriate diagnostic technique for the evaluation of vertebral alterations, as it allows to detect not only the exact morphology of the lesions, but also the pattern of bone marrow infiltration by the disease. Multiple treatment modalities can be used to manage multiple myeloma-related vertebral lesions. Surgery or radiotherapy is mainly employed in case of spinal cord compression, impending fractures, or intractable pain. Percutaneous vertebroplasty or balloon kyphoplasty can reduce local pain in a significant fraction of treated patients, without interfering with subsequent therapeutic programs. Systemic antimyeloma therapy with conventional chemotherapy or, more appropriately, with combinations of conventional chemotherapy and compounds acting on both neoplastic plasma cells and bone marrow microenvironment must be soon initiated in order to reduce bone resorption and, possibly, promote bone formation. Bisphosphonates should also be used in combination with antimyeloma therapy as they reduce bone resorption and prolong patients survival. A multidisciplinary approach is thus needed in order to properly manage spinal involvement in multiple myeloma. PMID:24381787

Vertebral stabilization using positively threaded profile pins and polymethylmethacrylate, with or without laminectomy, for spinal canal stenosis and vertebral instability caused by congenital thoracic vertebral anomalies.

PubMed

Aikawa, Takeshi; Kanazono, Shinichi; Yoshigae, Yuki; Sharp, Nicholas J H; Muñana, Karen R

2007-07-01

To describe diagnostic findings, surgical technique, and outcome in dogs with thoracic spinal canal stenosis and vertebral instability secondary to congenital vertebral anomalies. Retrospective clinical study. Dogs (n=9) with thoracic spinal canal stenosis. Medical records (1995-1996; 2000-2006) of 9 dogs with a myelographic diagnosis of spinal canal stenosis and/or vertebral instability secondary to congenital vertebral anomaly that were surgically managed by vertebral stabilization with or without laminectomy were reviewed. Data on pre- and postoperative neurologic status, diagnostic findings, surgical techniques, and outcomes were retrieved. Follow-up evaluations were performed at 1, 2, and 6 months. Long-term outcome was assessed by means of clinical examination or owner telephone interviews. Spinal cord compression was confirmed by myelography, and in 2 dogs, dynamic compression by stress myelography. Eight dogs regained the ability to ambulate postoperatively. One dog with a partial recovery regained voluntary movement but did not become ambulatory. Spinal cord injury secondary to congenital vertebral anomaly may have a good outcome when treated by vertebral stabilization with or without laminectomy. Adequate stabilization of the vertebrae and improved neurologic outcome were achieved in most dogs. Vertebral stabilization using positively threaded profile pins and polymethylmethacrylate with or without laminectomy is an effective treatment for spinal canal stenosis and vertebral instability secondary to congenital thoracic vertebral anomalies.

Using side-opening injection cannulas to prevent cement leakage in percutaneous vertebroplasty for osteoporotic vertebral compression fractures, does it really work?

PubMed

Li, Jigang; Li, Tao; Ma, Qiuhong; Li, Jianmin

2017-09-01

Percutaneous vertebroplasty has been widely applied in the treatment of osteoporotic vertebral compression fractures over the past two decades. However as one of the major complications, the rate of cement leakage seems not to be decreased significantly. In this study, the rate of cement leakage was compared between two groups using two different cement injection cannulas. The purpose was to determine the efficacy of side-opening cannula on preventing cement leakage in vertebroplasty for the treatment of osteoporotic vertebral compression fractures. A retrospective study was conducted from January 2013 to December 2015. Totally 225 patients who received bilateral vertebroplasty due to osteoporotic vertebral compression fractures were included in the study. The patients were divided into test group who received vertebroplasty with side-opening cannulas and control group who received vertebroplasty with front-opening cannulas. The patients' medical records were reviewed to determine the bone marrow density, preoperative vertebral compression ratio, preoperative and postoperative VAS, operation time, volume of injected bone cement, rate of cement leakage. Post-operative X-rays and CT scans were utilized to assess the degree of Cement leakage. Comparisons between groups and clinical results on VAS in each group were analyzed with appropriate test. All the patients were performed successfully without symptomatic complications. The back pain was significantly relieved after operation in both groups (P < 0.05). At 6 days and 6 months follow-up, there was no significant difference in the mean VAS score between the two groups (P > 0.05). The rate of cement leakage in the test group was significantly lower than that in the control group (P < 0.05). Percutaneous vertebroplasty with side-opening cannula is a safe and effective minimally invasive method in the treatment of osteoporotic vertebral compression fractures, the rate of cement leakage can be significantly reduced by redirecting the cement flow. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Repeated vertebral augmentation for new vertebral compression fractures of postvertebral augmentation patients: a nationwide cohort study

PubMed Central

Liang, Cheng-Loong; Wang, Hao-Kwan; Syu, Fei-Kai; Wang, Kuo-Wei; Lu, Kang; Liliang, Po-Chou

2015-01-01

Purpose Postvertebral augmentation vertebral compression fractures are common; repeated vertebral augmentation is usually performed for prompt pain relief. This study aimed to evaluate the incidence and risk factors of repeat vertebral augmentation. Methods We performed a retrospective, nationwide, population-based longitudinal observation study, using the National Health Insurance Research Database (NHIRD) of Taiwan. All patients who received vertebral augmentation for vertebral compression fractures were evaluated. The collected data included patient characteristics (demographics, comorbidities, and medication exposure) and repeat vertebral augmentation. Kaplan–Meier and stratified Cox proportional hazard regressions were performed for analyses. Results The overall incidence of repeat vertebral augmentation was 11.3% during the follow-up until 2010. Patients with the following characteristics were at greater risk for repeat vertebral augmentation: female sex (AOR=1.24; 95% confidence interval [CI]: 1.10–2.36), advanced age (AOR=1.60; 95% CI: 1.32–2.08), diabetes mellitus (AOR=4.31; 95% CI: 4.05–5.88), cerebrovascular disease (AOR=4.09; 95% CI: 3.44–5.76), dementia (AOR=1.97; 95% CI: 1.69–2.33), blindness or low vision (AOR=3.72; 95% CI: 2.32–3.95), hypertension (AOR=2.58; 95% CI: 2.35–3.47), and hyperlipidemia (AOR=2.09; 95% CI: 1.67–2.22). Patients taking calcium/vitamin D (AOR=2.98; 95% CI: 1.83–3.93), bisphosphonates (AOR=2.11; 95% CI: 1.26–2.61), or calcitonin (AOR=4.59; 95% CI: 3.40–5.77) were less likely to undergo repeat vertebral augmentation; however, those taking steroids (AOR=7.28; 95% CI: 6.32–8.08), acetaminophen (AOR=3.54; 95% CI: 2.75–4.83), or nonsteroidal anti-inflammatory drugs (NSAIDs) (AOR=6.14; 95% CI: 5.08–7.41) were more likely to undergo repeat vertebral augmentation. Conclusion We conclude that the incidence of repeat vertebral augmentation is rather high. An understanding of risk factors predicting repeat vertebral augmentation provides valuable basis to improve health care for geriatric populations. PMID:25848240

Surgical management of symptomatic T8 vertebral hemangioma: case report and review of the literature.

PubMed

Tucer, Bulent; Ekici, Mehmet Ali; Menku, Ahmet; Koc, Rahmi Kemal; Guclu, Bulent

2013-01-01

Vertebral hemangiomas are benign vascular lesions of the vertebral column; only 0.9-1.2% of all vertebral hemangiomas cause spinal cord compression. We report a 34-year-old female who was admitted to the neurosurgery clinic with a history of back pain, poor quality of life and easy fatigability for 1.5 years. Her medical history revealed a fall from a height of 2 meters 1.5 years ago. Neurology examination revealed bilateral hypoesthesia below the T8 level and hyperactive deep tendon reflexes in her left leg. Computed tomography scan of the thoracic spine showed T8 vertebral hemangioma, and magnetic resonance imaging showed a T8 hemangioma compressing the spinal cord. Surgical intervention was planned and T8 total laminectomy was performed. The tumor extending into the anterior spinal cord was resected, and T8 vertebroplasty with short segment posterior stabilization and fusion was performed. We aimed to present a new treatment approach for symptomatic vertebral hemangiomas and reviewed the relevant literature.

Bone mineral density loss in thoracic and lumbar vertebrae following radiation for abdominal cancers.

PubMed

Wei, Randy L; Jung, Brian C; Manzano, Wilfred; Sehgal, Varun; Klempner, Samuel J; Lee, Steve P; Ramsinghani, Nilam S; Lall, Chandana

2016-03-01

To investigate the relationship between abdominal chemoradiation (CRT) for locally advanced cancers and bone mineral density (BMD) reduction in the vertebral spine. Data from 272 patients who underwent abdominal radiation therapy from January 1997 to May 2015 were retrospectively reviewed. Forty-two patients received computed tomography (CT) scans of the abdomen prior to initiation and at least twice after radiation therapy. Bone attenuation (in Hounsfield unit) (HU) measurements were collected for each vertebral level from T7 to L5 using sagittal CT images. Radiation point dose was obtained at each mid-vertebral body from the radiation treatment plan. Percent change in bone attenuation (Δ%HU) between baseline and post-radiation therapy were computed for each vertebral body. The Δ%HU was compared against radiation dose using Pearson's linear correlation. Abdominal radiotherapy caused significant reduction in vertebral BMD as measured by HU. Patients who received only chemotherapy did not show changes in their BMD in this study. The Δ%HU was significantly correlated with the radiation point dose to the vertebral body (R=-0.472, P<0.001) within 4-8 months following RT. The same relationship persisted in subsequent follow up scans 9 months following RT (R=-0.578, P<0.001). Based on the result of linear regression, 5 Gy, 15 Gy, 25 Gy, 35 Gy, and 45 Gy caused 21.7%, 31.1%, 40.5%, 49.9%, and 59.3% decrease in HU following RT, respectively. Our generalized linear model showed that pre-RT HU had a positive effect (β=0.830) on determining post-RT HU, while number of months post RT (β=-0.213) and radiation point dose (β=-1.475) had a negative effect. A comparison of the predicted versus actual HU showed significant correlation (R=0.883, P<0.001) with the slope of the best linear fit=0.81. Our model's predicted HU were within ±20 HU of the actual value in 53% of cases, 70% of the predictions were within ±30 HU, 81% were within ±40 HU, and 90% were within ±50 HU of the actual post-RT HU. Four of 42 patients were found to have vertebral body compression fractures in the field of radiation. Patients who receive abdominal chemoradiation develop significant BMD loss in the thoracic and lumbar vertebrae. Treatment-related BMD loss may contribute to the development of vertebral compression fractures. A predictive model for post-CRT BMD changes may inform bone protective strategies in patients planned for abdominal CRT. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

[Effectiveness of long segment fixation combined with vertebroplasty for severe osteoporotic thoracolumbar compressive fractures].

PubMed

Xu, Zixing; Xu, Weihong; Wang, Changsheng; Luo, Hongbin; Li, Guishuang; Chen, Rongsheng

2013-11-01

To study the effectiveness of long segment fixation combined with vertebroplasty (LSF-VP) for severe osteoporotic thoracolumbar compressive fractures with kyphosis deformity. Between March 2006 and May 2012, a retrospective analysis was made on the clinical data of 48 cases of severe osteoporotic thoracolumbar compressive fractures with more than 50% collapse of the anterior vertebral body or more than 400 of sagittal angulation, which were treated by LSF-VP in 27 cases (LSF-VP group) or percutaneous kyphoplasty (PKP) in 21 cases (PKP group). All patients suffered from single thoracolumbar vertebral compressive fracture at T11 to L2. There was no significant difference in gender, age, spinal segment, and T values of bone mineral density between 2 groups (P > 0.05). The effectiveness of the treatment was appraised by visual analogue scale (VAS), Cobb angle of thoracolumbar kyphosis, height of anterior/posterior vertebral body, and compressive ratio of vertebrae before and after operations. The LSF-VP group had longer operation time, hospitalization days, and more bone cement injection volume than the PKP group, showing significant differences (P < 0.05). Intraoperative blood loss in LSF-VP group ranged from 220 to 1,050 mL (mean, 517 mL). No pulmonaryor cerebral embolism or cerebrospinal fluid leakage was found in both groups. Asymptomatic bone cement leakage was found in 3 cases of LSF-VP group and 2 cases of PKP group. The patients were followed up for 16-78 months (mean, 41.1 months) in LSF-VP group, and 12-71 months (mean, 42.1 months) in PKP group. No fixation failure such as loosened or broken pedicle screw was found in LSF-VP group during the follow-up, and no re-fracture or adjacent vertebral body fracture was found. Two cases in PKP group at 39 and 56 months after operation respectively were found to have poor maintenance of vertebral height and loss of rectification (Cobb angle was more than 40 degrees) with recurrence of pain, which were treated by second surgery of LSF-VP; another case had compressive fracture of the adjacent segment and thoracolumbar kyphosis at 16 months after operation, which was treated by second surgery of LSF-VP. There were significant differences in the other indexes between each pair of the three time points (P < 0.05), except the Cobb angle of thoracolumbar kyphosis, and the height of posterior vertebral body between discharge and last follow-up in LSF-VP group, and except the Cobb angle of thoracolumbar kyphosis and compressive ratio of bertebrae between discharge and last follow-up in PKP group (P > 0.05). After operation, the other indexes of LSF-VP group were significantly better than those of PKP group at each time point (P < 0.05), except the VAS score and the height of posterior vertebral body at discharge (P > 0.05). The effectiveness of LSF-VP is satisfactory in treating severe osteoporotic thoracolumbar compressive fractures with kyphosis deformity. LSF-VP can acquire better rectification of kyphosis and recovery of vertebral body height than PKP.

[Mathematical calculation of strength of the vertebral column in surgical treatment of unstable fractures of the spine].

PubMed

Orlov, S V; Kanykin, A Iu; Moskalev, V P; Shchedrenok, V V; Sedov, R L

2009-01-01

A mathematical model of a three-vertebra complex was developed in order to make an exact calculation of loss of supporting ability of the vertebral column in trauma. Mathematical description of the dynamic processes was based on Lagrange differential equation of the second order. The degree of compression and instability of the three-vertebra complex, established using mathematical modeling, determines the decision on the surgical treatment and might be considered as a prognostic criterion of the course of the compression trauma of the spine. The method of mathematical modeling of supporting ability of the vertebral column was used in 72 patients.

Rotational vertebral artery occlusion: mechanisms and long-term outcome.

PubMed

Choi, Kwang-Dong; Choi, Jae-Hwan; Kim, Ji-Soo; Kim, Hyo Jung; Kim, Min-Ji; Lee, Tae-Hong; Lee, Hyung; Moon, In Soo; Oh, Hui Jong; Kim, Jae-Il

2013-07-01

To elucidate the mechanisms and prognosis of rotational vertebral artery occlusion (RVAO). We analyzed clinical and radiological characteristics, patterns of induced nystagmus, and outcome in 21 patients (13 men, aged 29-77 years) with RVAO documented by dynamic cerebral angiography during an 8-year period at 3 University Hospitals in Korea. The follow-up periods ranged from 5 to 91 months (median, 37.5 months). Most patients (n=19; 90.5%) received conservative treatments. All the patients developed vertigo accompanied by tinnitus (38%), fainting (24%), or blurred vision (19%). Only 12 (57.1%) patients showed the typical pattern of RVAO during dynamic cerebral angiography, a compression of the dominant vertebral artery at the C1-2 level during contralateral head rotation. The induced nystagmus was mostly downbeat with horizontal and torsional components beating toward the compressed vertebral artery side. None of the patients with conservative treatments developed posterior circulation stroke, and 4 of them (21.1%) showed resolution of symptoms during the follow-ups. RVAO has various patterns of vertebral artery compression, and favorable long-term outcome with conservative treatments. In most patients with RVAO, the symptoms may be ascribed to asymmetrical excitation of the bilateral labyrinth induced by transient ischemia or by disinhibition from inferior cerebellar hypoperfusion. Conservative management might be considered as the first-line treatment of RVAO.

CIRSE Guidelines on Percutaneous Vertebral Augmentation

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

Tsoumakidou, Georgia, E-mail: gtsoumakidou@yahoo.com; Too, Chow Wei, E-mail: spyder55@gmail.com; Koch, Guillaume, E-mail: guillaume.koch@gmail.com

Vertebral compression fracture (VCF) is an important cause of severe debilitating back pain, adversely affecting quality of life, physical function, psychosocial performance, mental health and survival. Different vertebral augmentation procedures (VAPs) are used in order to consolidate the VCFs, relief pain,and whenever posible achieve vertebral body height restoration. In the present review we give the indications, contraindications, safety profile and outcomes of the existing percutaneous VAPs.

Magnetic resonance imaging features of Great Danes with and without clinical signs of cervical spondylomyelopathy

PubMed Central

Martin-Vaquero, Paula; da Costa, Ronaldo C.

2014-01-01

Objective To characterize and compare the MRI morphological features of the cervical vertebral column of Great Danes with and without clinical signs of cervical spondylomyelopathy (CSM). Design Prospective cohort study. Animals 30 Great Danes (15 clinically normal and 15 CSM-affected). Procedures All dogs underwent MRI of the cervical vertebral column (C2–3 through T1–2). Features evaluated included sites of subarachnoid space compression, spinal cord compression, or both; degree, cause, and direction of compression; MRI signal changes of the spinal cord; articular process (facet) joint characteristics; internal vertebral venous plexus visibility; and presence of extradural synovial cysts as well as presence and degree of intervertebral disk degeneration and foraminal stenosis. Results Clinically normal and CSM-affected dogs had 11 and 61 compressive sites, respectively, detected with MRI. All CSM-affected dogs had ≥ 1 site of spinal cord compression. No signal changes were observed in spinal cords of normal dogs, whereas 14 sites of hyperintensity were found in 9 CSM-affected dogs. Foraminal stenosis was present in 11 clinically normal and all CSM-affected dogs. The number of stenotic foraminal sites was significantly greater in the CSM-affected group, and severe stenosis appeared to be more common in this group than in the clinically normal group. Significant differences were identified between clinically normal and CSM-affected dogs with regard to amount of synovial fluid evident, regularity of articular surfaces, degree of articular process joint proliferation, and internal vertebral venous plexus visibility. Conclusions and Clinical Relevance Abnormalities were detected with MRI in several clinically normal Great Danes. Severe spinal cord compression, number of stenotic foraminal sites, and signal changes within the spinal cord distinguished CSM-affected from clinically normal Great Danes. PMID:25075822

Magnetic resonance imaging features of Great Danes with and without clinical signs of cervical spondylomyelopathy.

PubMed

Martin-Vaquero, Paula; da Costa, Ronaldo C

2014-08-15

To characterize and compare the MRI morphological features of the cervical vertebral column of Great Danes with and without clinical signs of cervical spondylomyelopathy (CSM). Prospective cohort study. 30 Great Danes (15 clinically normal and 15 CSM-affected). All dogs underwent MRI of the cervical vertebral column (C2-3 through T1-2). Features evaluated included sites of subarachnoid space compression, spinal cord compression, or both; degree, cause, and direction of compression; MRI signal changes of the spinal cord; articular process (facet) joint characteristics; internal vertebral venous plexus visibility; and presence of extradural synovial cysts as well as presence and degree of intervertebral disk degeneration and foraminal stenosis. Clinically normal and CSM-affected dogs had 11 and 61 compressive sites, respectively, detected with MRI. All CSM-affected dogs had ≥ 1 site of spinal cord compression. No signal changes were observed in spinal cords of normal dogs, whereas 14 sites of hyperintensity were found in 9 CSM-affected dogs. Foraminal stenosis was present in 11 clinically normal and all CSM-affected dogs. The number of stenotic foraminal sites was significantly greater in the CSM-affected group, and severe stenosis appeared to be more common in this group than in the clinically normal group. Significant differences were identified between clinically normal and CSM-affected dogs with regard to amount of synovial fluid evident, regularity of articular surfaces, degree of articular process joint proliferation, and internal vertebral venous plexus visibility. Abnormalities were detected with MRI in several clinically normal Great Danes. Severe spinal cord compression, number of stenotic foraminal sites, and signal changes within the spinal cord distinguished CSM-affected from clinically normal Great Danes.

[Complications of percutaneous kyphoplasty non-related with bone leakage in treating osteoporotic thoracolumbar vertebral compression fractures].

PubMed

Ru, Xuan-liong; Jiang, Zeng-hui; Gui, Xian-ge; Sun, Qi-cai; Song, Bo-Shan; Lin, Hang; He, Jian

2015-08-01

To analyze the complications of percutaneous kyphoplasty except bone leakge for the treatment of osteoporotic thoracolumbar vertebral compression fractures. From October 2008 to October 2012,178 patients with 224 osteoporotic vertebral compression fractures were treated with percutaneous kyphoplasty under local anethsia. There were 72 males and 106 females,ranging in age from 58 to 92 years old,with an average of 75.3 years,including 93 thoracic vertebrae and 131 lumbar vertebrae. The complications except bone cement leakage were analyzed during operation and after operation. All operations were successful and all patients were followed up from 12 to 60 months with an average of 26.2 months. No death was found. Bone cement leakage occurred in 27 cases, about 15.1% in 178 cases; and complications except bone cement leakage occurred in 15 cases. There was 1 case with cardiac arrest,was completely recovery by cardiopulmonary resuscitation (CPR) immediately; and 1 case with temporary absence of breathing,was recovery after treatment. There were 3 cases with fall of blood pressure and slower of heart rate; 1 case with intestinal obstruction; 2 cases with local hematoma and 1 case with intercostal neuralgia. Vertebral body fractures of 2 cases were split by bone cement and the fractures of adjacent body occurred in 4 cases. It's uncommon complication except bone cement leakge in treatment of osteoporotic thoracolumbar vertebral compression fractures with percutaneous kyphoplasty. The complication of cardiopulmonary system is a high risk in surgery; and cytotoxicity of bone cement,nervous reflex,fat embolism and alteration of intravertebral pressure may be main reasons.

[Vertebroplasty: state of the art].

PubMed

Chiras, J; Barragán-Campos, H M; Cormier, E; Jean, B; Rose, M; LeJean, L

2007-09-01

Over the last 10 years, there has been much development in the management of metastatic and osteoporotic vertebral compression fractures using vertebroplasty. This percutaneous image-guided interventional radiology procedure allows stabilization of a vertebral body by injection of an acrylic cement and frequently results in significant symptomatic relief. During cement polymerisation, an exothermic reaction may destroy adjacent tumor cells. Advances have been made to reduce complications from extravasation of cement in veins or surrounding soft tissues. Safety relates to experience but also to technical parameters: optimal cement radio-density, adequate digital fluoroscopy unit (single or bi-plane digital angiography unit), development of cements other than PMMA to avoid the risk of adjacent vertebral compression fractures. The rate of symptomatic relief from vertebroplasty performed for its principal indications (vertebral hemangioma, metastases, osteoporotic fractures) reaches 90-95%. The rate of complications is about 2% for metastases and less than 0.5% for osteoporotic fractures. Vertebroplasty plays a major role in the management of specific bone weakening vertebral lesions causing, obviating the need for kyphoplasty.

Development and validation of a subject-specific finite element model of the functional spinal unit to predict vertebral strength.

PubMed

Lee, Chu-Hee; Landham, Priyan R; Eastell, Richard; Adams, Michael A; Dolan, Patricia; Yang, Lang

2017-09-01

Finite element models of an isolated vertebral body cannot accurately predict compressive strength of the spinal column because, in life, compressive load is variably distributed across the vertebral body and neural arch. The purpose of this study was to develop and validate a patient-specific finite element model of a functional spinal unit, and then use the model to predict vertebral strength from medical images. A total of 16 cadaveric functional spinal units were scanned and then tested mechanically in bending and compression to generate a vertebral wedge fracture. Before testing, an image processing and finite element analysis framework (SpineVox-Pro), developed previously in MATLAB using ANSYS APDL, was used to generate a subject-specific finite element model with eight-node hexahedral elements. Transversely isotropic linear-elastic material properties were assigned to vertebrae, and simple homogeneous linear-elastic properties were assigned to the intervertebral disc. Forward bending loading conditions were applied to simulate manual handling. Results showed that vertebral strengths measured by experiment were positively correlated with strengths predicted by the functional spinal unit finite element model with von Mises or Drucker-Prager failure criteria ( R 2  = 0.80-0.87), with areal bone mineral density measured by dual-energy X-ray absorptiometry ( R 2  = 0.54) and with volumetric bone mineral density from quantitative computed tomography ( R 2  = 0.79). Large-displacement non-linear analyses on all specimens did not improve predictions. We conclude that subject-specific finite element models of a functional spinal unit have potential to estimate the vertebral strength better than bone mineral density alone.

[Effect of different bone cement dispersion types in the treatment of osteoporotic vertebral compression fracture].

PubMed

Zhao, Yong-Sheng; Li, Qiang; Li, Qiang; Zheng, Yan-Ping

2017-05-25

To observe different bone cement dispersion types of PVP, PKP and manipulative reduction PVP and their effects in the treatment of senile osteoporotic vertebral compression fractures and the bone cement leakage rate. The clinical data of patients with osteoporotic vertebral compression fractures who underwent unilateral vertebroplasty from January 2012 to January 2015 was retrospectively analyzed. Of them, 56 cases including 22 males and 34 females aged from 60 to 78 years old were treated by PVP operation; Fouty-eight cases including 17 males and 31 females aged from 61 to 79 years old were treated by PKP operation; Forty-three cases including 15 males and 28 females aged from 60 to 76 years old were treated by manipulative reduction PVP operation. AP and lateral DR films were taken after the operation; the vertebral bone cement diffusion district area and mass district area were calculated with AutoCAD graphics processing software by AP and lateral DR picture, then ratio(K) of average diffusion area and mass area were calculated, defining K<50% as mass type, 50%<=K<=100% as mixed type and K>100% as diffusion type. Different bone cement dispersion types of PVP, PKP and manipulative reduction PVP operation were analyzed. According to bone cement dispersion types, patients were divided into diffusion type, mixed type and mass type groups.Visual analogue scale (VAS), vertebral body compression rate, JOA score and bone cement leakage rate were observed. All patients were followed up for 12-24 months with an average of 17.2 months. There was significant difference in bone cement dispersion type among three groups ( P <0.05). The constituent ratio of diffusion type, mixed type and mass type in PVP operation was 46.43%, 35.71%, 17.86%, in PKP was 16.67%, 37.50% , 45.83%, and in manipulative reduction PVP was 37.21%, 44.19% and 18.60%, respectively. PVP operation and manipulative reduction PVP were mainly composed of diffusion type and mixed type, while PKP was mainly composed of mass type and mixed type. There was no significant difference in VAS score, JOA score and bone cement leakage rate among three groups. There was statistically significant difference in postoperative vertebral body compression rate among three bone cement dispersion types( P <0.05), postoperative vertebral body compression rate in diffusion type group at 24 h postoperatively and final follow-up was (17.31±5.06)% and(18.58±4.91)%, respectively. In mixed type group, it was(14.21±5.15)% and(14.59±5.07)%, respectively. In mass type group, it was(13.89±5.02)% and(14.28±4.94)%, respectively. Bone cement dispersion type is different in PVP, PKP and manipulative reduction PVP operation. The bone cement dispersion of mass type and mixed type to recovery of compressed vertebral body is better than diffusion type, and there is no obvious difference in clinical effect in different bone cement dispersion type early and middle term.

Risk Prediction of New Adjacent Vertebral Fractures After PVP for Patients with Vertebral Compression Fractures: Development of a Prediction Model

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

Zhong, Bin-Yan; He, Shi-Cheng; Zhu, Hai-Dong

PurposeWe aim to determine the predictors of new adjacent vertebral fractures (AVCFs) after percutaneous vertebroplasty (PVP) in patients with osteoporotic vertebral compression fractures (OVCFs) and to construct a risk prediction score to estimate a 2-year new AVCF risk-by-risk factor condition.Materials and MethodsPatients with OVCFs who underwent their first PVP between December 2006 and December 2013 at Hospital A (training cohort) and Hospital B (validation cohort) were included in this study. In training cohort, we assessed the independent risk predictors and developed the probability of new adjacent OVCFs (PNAV) score system using the Cox proportional hazard regression analysis. The accuracy ofmore » this system was then validated in both training and validation cohorts by concordance (c) statistic.Results421 patients (training cohort: n = 256; validation cohort: n = 165) were included in this study. In training cohort, new AVCFs after the first PVP treatment occurred in 33 (12.9%) patients. The independent risk factors were intradiscal cement leakage and preexisting old vertebral compression fracture(s). The estimated 2-year absolute risk of new AVCFs ranged from less than 4% in patients with neither independent risk factors to more than 45% in individuals with both factors.ConclusionsThe PNAV score is an objective and easy approach to predict the risk of new AVCFs.« less

Vertebral Augmentation with Nitinol Endoprosthesis: Clinical Experience in 40 Patients with 1-Year Follow-up

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

Anselmetti, Giovanni Carlo, E-mail: gc.anselmetti@fastwebnet.it; Manca, Antonio, E-mail: anto.manca@gmail.com; Marcia, Stefano, E-mail: stemarcia@gmail.com

PurposeThis study was designed to assess the clinical outcomes of patients treated by vertebral augmentation with nitinol endoprosthesis (VNE) to treat painful vertebral compression fractures.MethodsForty patients with one or more painful osteoporotic VCF, confirmed by MRI and accompanied by back-pain unresponsive to a minimum 2 months of conservative medical treatment, underwent VNE at 42 levels. Preoperative and postoperative pain measured with Visual Analog Scale (VAS), disability measured by Oswestry Disability Index (ODI), and vertebral height restoration (measured with 2-dimensional reconstruction CT) were compared at last follow-up (average follow-up 15 months). Cement extravasation, subsequent fractures, and implant migration were recorded.ResultsLong-term follow-up was obtainedmore » in 38 of 40 patients. Both VAS and ODI significantly improved from a median of 8.0 (range 5–10) and 66 % (range 44–88 %) to 0.5 (range 0–8) and 6 % (range 6–66 %), respectively, at 1 year (p < 0.0001). Vertebral height measurements comparing time points increased in a statistically significant manner (ANOVA, p < 0.001). Overall cement extravasation rate was 9.5 %. Discal and venous leakage rates were 7.1 and 0 % respectively. No symptomatic extravasations occurred. Five of 38 (13.1 %) patients experienced new spontaneous, osteoporotic fractures. No device change or migration was observed.ConclusionsVNE is a safe and effective procedure that is able to provide long-lasting pain relief and durable vertebral height gain with a low rate of new fractures and cement leakages.« less

Computerized detection of vertebral compression fractures on lateral chest radiographs: Preliminary results with a tool for early detection of osteoporosis

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

Kasai, Satoshi; Li Feng; Shiraishi, Junji

Vertebral fracture (or vertebral deformity) is a very common outcome of osteoporosis, which is one of the major public health concerns in the world. Early detection of vertebral fractures is important because timely pharmacologic intervention can reduce the risk of subsequent additional fractures. Chest radiographs are used routinely for detection of lung and heart diseases, and vertebral fractures can be visible on lateral chest radiographs. However, investigators noted that about 50% of vertebral fractures visible on lateral chest radiographs were underdiagnosed or under-reported, even when the fractures were severe. Therefore, our goal was to develop a computerized method for detectionmore » of vertebral fractures on lateral chest radiographs in order to assist radiologists' image interpretation and thus allow the early diagnosis of osteoporosis. The cases used in this study were 20 patients with severe vertebral fractures and 118 patients without fractures, as confirmed by the consensus of two radiologists. Radiologists identified the locations of fractured vertebrae, and they provided morphometric data on the vertebral shape for evaluation of the accuracy of detecting vertebral end plates by computer. In our computerized method, a curved search area, which included a number of vertebral end plates, was first extracted automatically, and was straightened so that vertebral end plates became oriented horizontally. Edge candidates were enhanced by use of a horizontal line-enhancement filter in the straightened image, and a multiple thresholding technique, followed by feature analysis, was used for identification of the vertebral end plates. The height of each vertebra was determined from locations of identified vertebral end plates, and fractured vertebrae were detected by comparison of the measured vertebral height with the expected height. The sensitivity of our computerized method for detection of fracture cases was 95% (19/20), with 1.03 (139/135) false-positive fractures per image. The accuracy of identifying vertebral end plates, marked by radiologists in a morphometric study, was 76.6% (400/522) and 70.9% (420/592) for cases used for training and those for testing, respectively. We prepared 32 additional fracture cases for a validation test, and we examined the detection accuracy of our computerized method. The sensitivity for these cases was 75% (24/32) at 1.03 (33/32) false-positive fractures per image. Our preliminary results show that the automated computerized scheme for detecting vertebral fractures on lateral chest radiographs has the potential to assist radiologists in detecting vertebral fractures.« less

A finite element evaluation of the moment arm hypothesis for altered vertebral shear failure force.

PubMed

Howarth, Samuel J; Karakolis, Thomas; Callaghan, Jack P

2015-01-01

The mechanism of vertebral shear failure is likely a bending moment generated about the pars interarticularis by facet contact, and the moment arm length (MAL) between the centroid of facet contact and the location of pars interarticularis failure has been hypothesised to be an influential modulator of shear failure force. To quantitatively evaluate this hypothesis, anterior shear of C3 over C4 was simulated in a finite element model of the porcine C3-C4 vertebral joint with each combination of five compressive force magnitudes (0-60% of estimated compressive failure force) and three postures (flexed, neutral and extended). Bilateral locations of peak stress within C3's pars interarticularis were identified along with the centroids of contact force on the inferior facets. These measurements were used to calculate the MAL of facet contact force. Changes in MAL were also related to shear failure forces measured from similar in vitro tests. Flexed and extended vertebral postures respectively increased and decreased the MAL by 6.6% and 4.8%. The MAL decreased by only 2.6% from the smallest to the largest compressive force. Furthermore, altered MAL explained 70% of the variance in measured shear failure force from comparable in vitro testing with larger MALs being associated with lower shear failure forces. Our results confirmed that the MAL is indeed a significant modulator of vertebral shear failure force. Considering spine flexion is necessary when assessing low-back shear injury potential because of the association between altered facet articulation and lower vertebral shear failure tolerance.

Height restoration of osteoporotic vertebral compression fractures using different intravertebral reduction devices: a cadaveric study.

PubMed

Krüger, Antonio; Oberkircher, Ludwig; Figiel, Jens; Floßdorf, Felix; Bolzinger, Florent; Noriega, David C; Ruchholtz, Steffen

2015-05-01

The treatment of osteoporotic vertebral compression fractures using transpedicular cement augmentation has grown significantly during the past two decades. Balloon kyphoplasty was developed to restore vertebral height and improve sagittal alignment. Several studies have shown these theoretical improvements cannot be transferred universally to the clinical setting. The aim of the current study is to evaluate two different procedures used for percutaneous augmentation of vertebral compression fractures with respect to height restoration: balloon kyphoplasty and SpineJack. Twenty-four vertebral bodies of two intact, fresh human cadaveric spines (T6-L5; donor age, 70 years and 60 years; T-score -6.8 points and -6.3 points) were scanned using computed tomography (CT) and dissected into single vertebral bodies. Vertebral wedge compression fractures were created by a material testing machine (Universal testing machine, Instron 5566, Darmstadt, Germany). The axial load was increased continuously until the height of the anterior edge of the vertebral body was reduced by 40% of the initial measured values. After 15 minutes, the load was decreased manually to 100 N. After postfracture CT, the clamped vertebral bodies were placed in a custom-made loading frame with a preload of 100 N. Twelve vertebral bodies were treated using SpineJack (SJ; Vexim, Balma, France), the 12 remaining vertebral bodies were treated with balloon kyphoplasty (BKP; Kyphon, Medtronic, Sunnyvale, CA, USA). The load was maintained during the procedure until the cement set completely. Posttreatment CT was performed. Anterior, central, and posterior height as well as the Beck index were measured prefracture and postfracture as well as after treatment. For anterior height restoration (BKP, 0.14±1.48 mm; SJ, 3.34±1.19 mm), central height restoration (BKP, 0.91±1.04 mm; SJ, 3.24±1.22 mm), and posterior restoration (BKP, 0.37±0.57 mm; SJ, 1.26±1.05), as well as the Beck index (BKP, 0.00±0.06 mm; SJ, 0.10±0.06), the values for the SpineJack group were significantly higher (p<.05) CONCLUSION: The protocols for creating wedge fractures and using the instrumentation under a constant preload of 100 N led to reproducible results and effects. The study showed that height restoration was significantly better in the SpineJack group compared with the balloon kyphoplasty group. The clinical implications include a better restoration of the sagittal balance of the spine and a reduction of the kyphotic deformity, which may relate to clinical outcome and the biological healing process. Copyright © 2015 Elsevier Inc. All rights reserved.

Prospective Single-Site Experience with Radiofrequency-Targeted Vertebral Augmentation for Osteoporotic Vertebral Compression Fracture

PubMed Central

Moser, Franklin G.; Maya, Marcel M.; Blaszkiewicz, Laura; Scicli, Andrea; Miller, Larry E.; Block, Jon E.

2013-01-01

Vertebral augmentation procedures are widely used to treat osteoporotic vertebral compression fractures (VCFs). We report our initial experience with radiofrequency-targeted vertebral augmentation (RF-TVA) in 20 patients aged 50 to 90 years with single-level, symptomatic osteoporotic VCF between T10 and L5, back pain severity > 4 on a 0 to 10 scale, Oswestry Disability Index ≥ 21%, 20% to 90% vertebral height loss compared to adjacent vertebral body, and fracture age < 6 months. After treatment, patients were followed through hospital discharge and returned for visits after 1 week, 1 month, and 3 months. Back pain severity improved 66% (P < 0.001), from 7.9 (95% CI: 7.1 to 8.6) at pretreatment to 2.7 (95% CI: 1.5 to 4.0) at 3 months. Back function improved 46% (P < 0.001), from 74 (95% CI: 69% to 79%) at pretreatment to 40 (95% CI: 33% to 47%) at 3 months. The percentage of patients regularly consuming pain medication was 70% at pretreatment and only 21% at 3 months. No adverse events related to the device or procedure were reported. RF-TVA reduces back pain severity, improves back function, and reduces pain medication requirements with no observed complications in patients with osteoporotic VCF. PMID:24228187

Comparison of Radiofrequency-targeted Vertebral Augmentation With Balloon Kyphoplasty for the Treatment of Vertebral Compression Fractures: 2-Year Results.

PubMed

Bornemann, Rahel; Jansen, Tom R; Kabir, Koroush; Pennekamp, Peter H; Stüwe, Brit; Wirtz, Dieter C; Pflugmacher, Robert

2017-04-01

A retrospective study. The aim of this study was the evaluation of the safety and effectiveness of radiofrequency-targeted vertebral augmentation (RF-TVA) in comparison with balloon kyphoplasty (BK) for the treatment of acute painful vertebral compression fractures (VCFs) on the basis of matched pairs. Vertebroplasty and BK are the common surgical interventions for the treatment of VCF. Both are effective and safe but pose some risks such as adjacent fractures and cement leakage. In 2009, RF-TVA was introduced as an innovative augmentation procedure for the treatment of VCF. A total of 192 patients (116 female; 51-90 y) with VCF (n=303) at 1 to 3 levels were treated with RF-TVA or BK. Functionality (Oswestry Disability Index), pain (visual analogue scale), vertebral height (anterior, middle), and kyphotic angle were evaluated over a 2-year period (postoperatively, 3-4 d, 3, 6, 12, and 24 mo). In addition, operating time and occurrence of cement leakage were recorded. Pain and functionality were significantly improved after both treatments. In both groups, there was an increase in the vertebral height and a decrease in the kyphotic angle, which remained relatively consistent during 24 months. The incidence of cement leakage was 9.4% (n=9) in the RF-TVA group and 24.0% (n=25) in the BK group. The mean operating time with radiofrequency kyphoplasty was 25.9±9.9 minutes, and with balloon kyphoplasty 48.0±18.4 minutes. RF-TVA is a safe and effective procedure for the treatment of vertebral compression fractures when compared with BK. Improvement in pain and functional scores after RF-TVA are durable through 24 months postprocedure and remained better than those after BK at long-term follow-up. Operating time for RF-TVA is shorter and the risk of cement leakage is lower. Both procedures provided similar results in vertebral height restoration and reduction in the kyphotic angle.

Thoracic Vertebral Hemangioma with Spinal Cord Compression: Multidisciplinary Surgical Treatment and Follow-up of Six Patients.

PubMed

Zhang, Hui-Lin; Hu, Yong-Cheng; Aryal, Rajendra; He, Xin; Lun, Deng-Xing; Zhao, Li-Ming

2016-11-01

To provide useful insights of multidisciplinary surgical treatment for vertebral hemangioma with spinal cord compression. From 2009 to 2014, data on six patients who were diagnosed with cord compression vertebral hemangioma were reviewed and analyzed retrospectively. There were five women and one man with a mean age of 48.6 years (range, 26-68 years). All the patients were treated by multidisciplinary approach, including use of gelfoam, pedicle screw instrumentation, vertebroplasty, and decompression laminectomy. Neurological status and Frankel grades were documented, CT scan and MRI were performed after surgery. The follow-up period ranged from 8 to 54 months. Mean blood loss was around 367 mL, and the mean surgical time was 2.30 h. All patients had uneventful intraoperative and postoperative courses and reported symptomatic and neurological relief to varying degrees, at an average follow-up period of 23 months. Bone cement distribution was disseminated homogeneously over the affected vertebra and no leakage was observed. All the patients had a complete restoration to Frankel grade E. The postoperative and follow-up imaging showed that the implant was in perfect position, and no recurrence occurred in all patients. The vertebral hemangioma with cord compression is a challenge to surgeons for therapeutic improvement, and an active involvement of several disciplines as well as performance of multidisciplinary surgical treatment can be crucial in achieving favorable results. © 2016 Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.

Biomechanical Comparison of Robotically Applied Pure Moment, Ideal Follower Load, and Novel Trunk Weight Loading Protocols on L4-L5 Cadaveric Segments during Flexion-Extension.

PubMed

Bennett, Charles R; DiAngelo, Denis J; Kelly, Brian P

2015-01-01

Extremely few in-vitro biomechanical studies have incorporated shear loads leaving a gap for investigation, especially when applied in combination with compression and bending under dynamic conditions. The objective of this study was to biomechanically compare sagittal plane application of two standard protocols, pure moment (PM) and follower load (FL), with a novel trunk weight (TW) loading protocol designed to induce shear in combination with compression and dynamic bending in a neutrally potted human cadaveric L4-L5 motion segment unit (MSU) model. A secondary objective and novelty of the current study was the application of all three protocols within the same testing system serving to reduce artifacts due to testing system variability. Six L4-L5 segments were tested in a Cartesian load controlled system in flexion-extension to 8Nm under PM, simulated ideal 400N FL, and vertically oriented 400N TW loading protocols. Comparison metrics used were rotational range of motion (RROM), flexibility, neutral zone (NZ) range of motion, and L4 vertebral body displacements. Significant differences in vertebral body translations were observed with different initial force applications but not with subsequent bending moment application. Significant reductions were observed in combined flexion-extension RROM, in flexibility during extension, and in NZ region flexibility with the TW loading protocol as compared to PM loading. Neutral zone ranges of motion were not different between all protocols. The combined compression and shear forces applied across the spinal joint in the trunk weight protocol may have a small but significantly increased stabilizing effect on segment flexibility and kinematics during sagittal plane flexion and extension.

Biomechanical Comparison of Robotically Applied Pure Moment, Ideal Follower Load, and Novel Trunk Weight Loading Protocols on L4-L5 Cadaveric Segments during Flexion-Extension

PubMed Central

Bennett, Charles R.; DiAngelo, Denis J.

2015-01-01

Background Extremely few in-vitro biomechanical studies have incorporated shear loads leaving a gap for investigation, especially when applied in combination with compression and bending under dynamic conditions. The objective of this study was to biomechanically compare sagittal plane application of two standard protocols, pure moment (PM) and follower load (FL), with a novel trunk weight (TW) loading protocol designed to induce shear in combination with compression and dynamic bending in a neutrally potted human cadaveric L4-L5 motion segment unit (MSU) model. A secondary objective and novelty of the current study was the application of all three protocols within the same testing system serving to reduce artifacts due to testing system variability. Methods Six L4-L5 segments were tested in a Cartesian load controlled system in flexion-extension to 8Nm under PM, simulated ideal 400N FL, and vertically oriented 400N TW loading protocols. Comparison metrics used were rotational range of motion (RROM), flexibility, neutral zone (NZ) range of motion, and L4 vertebral body displacements. Results Significant differences in vertebral body translations were observed with different initial force applications but not with subsequent bending moment application. Significant reductions were observed in combined flexion-extension RROM, in flexibility during extension, and in NZ region flexibility with the TW loading protocol as compared to PM loading. Neutral zone ranges of motion were not different between all protocols. Conclusions The combined compression and shear forces applied across the spinal joint in the trunk weight protocol may have a small but significantly increased stabilizing effect on segment flexibility and kinematics during sagittal plane flexion and extension. PMID:26273551

Augmentation of failed human vertebrae with critical un-contained lytic defect restores their structural competence under functional loading: An experimental study.

PubMed

Alkalay, Ron N; von Stechow, Dietrich; Hackney, David B

2015-07-01

Lytic spinal lesions reduce vertebral strength and may result in their fracture. Vertebral augmentation is employed clinically to provide mechanical stability and pain relief for vertebrae with lytic lesions. However, little is known about its efficacy in strengthening fractured vertebrae containing lytic metastasis. Eighteen unembalmed human lumbar vertebrae, having simulated uncontained lytic defects and tested to failure in a prior study, were augmented using a transpedicular approach and re-tested to failure using a wedge fracture model. Axial and moment based strength and stiffness parameters were used to quantify the effect of augmentation on the structural response of the failed vertebrae. Effects of cement volume, bone mineral density and vertebral geometry on the change in structural response were investigated. Augmentation increased the failed lytic vertebral strength [compression: 85% (P<0.001), flexion: 80% (P<0.001), anterior-posterior shear: 95%, P<0.001)] and stiffness [(40% (P<0.05), 53% (P<0.05), 45% (P<0.05)]. Cement volume correlated with the compressive strength (r(2)=0.47, P<0.05) and anterior-posterior shear strength (r(2)=0.52, P<0.05) and stiffness (r(2)=0.45, P<0.05). Neither the geometry of the failed vertebrae nor its pre-fracture bone mineral density correlated with the volume of cement. Vertebral augmentation is effective in bolstering the failed lytic vertebrae compressive and axial structural competence, showing strength estimates up to 50-90% of historical values of osteoporotic vertebrae without lytic defects. This modest increase suggests that lytic vertebrae undergo a high degree of structural damage at failure, with strength only partially restored by vertebral augmentation. The positive effect of cement volume is self-limiting due to extravasation. Copyright © 2015. Published by Elsevier Ltd.

Whole-body low-dose computed tomography in multiple myeloma staging: Superior diagnostic performance in the detection of bone lesions, vertebral compression fractures, rib fractures and extraskeletal findings compared to radiography with similar radiation exposure.

PubMed

Lambert, Lukas; Ourednicek, Petr; Meckova, Zuzana; Gavelli, Giampaolo; Straub, Jan; Spicka, Ivan

2017-04-01

The primary objective of the present prospective study was to compare the diagnostic performance of conventional radiography (CR) and whole-body low-dose computed tomography (WBLDCT) with a comparable radiation dose reconstructed using hybrid iterative reconstruction technique, in terms of the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings. The secondary objective was to evaluate lesion attenuation in relation to its size. A total of 74 patients underwent same-day skeletal survey by CR and WBLDCT. In CR and WBLDCT, two readers assessed the number of osteolytic lesions at each region and stage according to the International Myeloma Working Group (IMWG) criteria. A single reader additionally assessed extraskeletal findings and their significance, the number of vertebral compressions and bone fractures. The radiation exposure was 2.7±0.9 mSv for WBLDCT and 2.5±0.9 mSv for CR (P=0.054). CR detected bone involvement in 127 out of 486 regions (26%; P<0.0001), confirmed by WBLDCT. CR underestimated the disease stage in 16% and overestimated it in 8% of the patients (P=0.0077). WBLDCT detected more rib fractures compared with CR (188 vs. 47; P<0.0001), vertebral compressions (93 vs. 67; P=0.010) and extraskeletal findings (194 vs. 52; P<0.0001). There was no correlation observed between lesion size (≥5 mm) and its attenuation (r=-0.006; P=0.93). The inter-observer agreement for the presence of osteolytic lesions was κ=0.76 for WBLDCT, and κ=0.55 for CR. The present study concluded that WBLDCT with hybrid iterative reconstruction technique demonstrates superiority to CR with an identical radiation dose in the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings, which results in up- or downstaging in 24% patients according to the IMWG criteria. The attenuation of osteolytic lesions can be measured with the avoidance of the partial volume effect.

Surgical treatment of hematogenous vertebral Aspergillus osteomyelitis.

PubMed

Bridwell, K H; Campbell, J W; Barenkamp, S J

1990-04-01

Three cases of Aspergillus fumigatas vertebral osteomyelitis failed courses of medical treatment. Each was subsequently treated with anterior vertebral debridement and posterior segmental spinal instrumentation. Despite poor nutritional and immune systems, resolution of the infection and subsequent anterior ankylosis occurred in each patient, with follow-up ranging from 1 to 3 years. If patients with aspergillus vertebral osteomyelitis do not respond to medical treatment, early surgical debridement and stabilization in combination with intravenous amphotericin B can lead to resolution and bony ankylosis.

Effects of Neonatal Enzyme Replacement Therapy and Simvastatin Treatment on Cervical Spine Disease in Mucopolysaccharidosis I Dogs

PubMed Central

Chiaro, Joseph A; O’Donnell, Patricia; Shore, Eileen M; Malhotra, Neil R; Ponder, Katherine P; Haskins, Mark E; Smith, Lachlan J

2014-01-01

Mucopolysaccharidosis I (MPS I) is a lysosomal storage disease characterized by deficient α-L-iduronidase activity, leading to the accumulation of poorly degraded glycosaminoglycans (GAGs). Children with MPS I exhibit high incidence of spine disease, including accelerated disc degeneration and vertebral dysplasia, which in turn lead to spinal cord compression and kypho-scoliosis. In this study we investigated the efficacy of neonatal enzyme replacement therapy (ERT), alone or in combination with oral simvastatin (ERT+SIM) for attenuating cervical spine disease progression in MPS I, using a canine model. Four groups were studied: normal controls; MPS I untreated; MPS I ERT treated; and MPS I ERT+SIM treated. Animals were euthanized at one year-of-age. Intervertebral disc condition and spinal cord compression were evaluated from MRIs and plain radiographs, vertebral bone condition and odontoid hypoplasia were evaluated using microcomputed tomography, and epiphyseal cartilage to bone conversion was evaluated histologically. Untreated MPS I animals exhibited more advanced disc degeneration and more severe spinal cord compression than normal animals. Both treatment groups resulted in partial preservation of disc condition and cord compression, with ERT+SIM not significantly better than ERT alone. Untreated MPS I animals had significantly lower vertebral trabecular bone volume and mineral density, while ERT treatment resulted in partial preservation of these properties. ERT+SIM treatment demonstrated similar, but not greater, efficacy. Both treatment groups partially normalized endochondral ossification in the vertebral epiphyses (as indicated by absence of persistent growth plate cartilage), and odontoid process size and morphology. These results indicate that ERT begun from a very early age attenuates the severity of cervical spine disease in MPS I, particularly for the vertebral bone and odontoid process, and that additional treatment with simvastatin does not provide a significant additional benefit over ERT alone. PMID:24898323

Risk of Vertebral Fracture in Patients Diagnosed with a Depressive Disorder: A Nationwide Population-Based Cohort Study

PubMed Central

Lee, Shyh-Chyang; Hu, Li-Yu; Huang, Min-Wei; Shen, Cheng-Che; Huang, Wei-Lun; Lu, Ti; Hsu, Chiao-Lin; Pan, Chih-Chuan

2017-01-01

OBJECTIVE: Previous studies have reported that depression may play a crucial role in the occurrence of vertebral fractures. However, a clear correlation between depressive disorders and osteoporotic fractures has not been established. We explored the association between depressive disorders and subsequent new-onset vertebral fractures. Additionally, we aimed to identify the potential risk factors for vertebral fracture in patients with a depressive disorder. METHODS: We studied patients listed in the Taiwan National Health Insurance Research Database who were diagnosed with a depressive disorder by a psychiatrist. The comparison cohort consisted of age- and sex-matched patients without a depressive disorder. The incidence rate and hazard ratios of subsequent vertebral fracture were evaluated. We used Cox regression analysis to evaluate the risk of vertebral fracture among patients with a depressive disorder. RESULTS: The total number of patients with and without a depressive disorder was 44,812. The incidence risk ratio (IRR) between these 2 cohorts indicated that depressive disorder patients had a higher risk of developing a subsequent vertebral fracture (IRR=1.41, 95% confidence interval [CI]=1.26–1.57, p<0.001). In the multivariate analysis, the depressive disorder cohort showed a higher risk of vertebral fracture than the comparison cohort (adjusted hazard ratio=1.24, 95% CI=1.11–1.38, p<0.001). Being older than 50 years, having a lower monthly income, and having hypertension, diabetes mellitus, cerebrovascular disease, chronic obstructive pulmonary disease, autoimmune disease, or osteoporosis were considered predictive factors for vertebral fracture in patients with depressive disorders. CONCLUSIONS: Depressive disorders may increase the risk of a subsequent new-onset vertebral fracture. PMID:28226032

Risk of Vertebral Fracture in Patients Diagnosed with a Depressive Disorder: A Nationwide Population-Based Cohort Study.

PubMed

Lee, Shyh-Chyang; Hu, Li-Yu; Huang, Min-Wei; Shen, Cheng-Che; Huang, Wei-Lun; Lu, Ti; Hsu, Chiao-Lin; Pan, Chih-Chuan

2017-01-01

Previous studies have reported that depression may play a crucial role in the occurrence of vertebral fractures. However, a clear correlation between depressive disorders and osteoporotic fractures has not been established. We explored the association between depressive disorders and subsequent new-onset vertebral fractures. Additionally, we aimed to identify the potential risk factors for vertebral fracture in patients with a depressive disorder. We studied patients listed in the Taiwan National Health Insurance Research Database who were diagnosed with a depressive disorder by a psychiatrist. The comparison cohort consisted of age- and sex-matched patients without a depressive disorder. The incidence rate and hazard ratios of subsequent vertebral fracture were evaluated. We used Cox regression analysis to evaluate the risk of vertebral fracture among patients with a depressive disorder. The total number of patients with and without a depressive disorder was 44,812. The incidence risk ratio (IRR) between these 2 cohorts indicated that depressive disorder patients had a higher risk of developing a subsequent vertebral fracture (IRR=1.41, 95% confidence interval [CI]=1.26-1.57, p<0.001). In the multivariate analysis, the depressive disorder cohort showed a higher risk of vertebral fracture than the comparison cohort (adjusted hazard ratio=1.24, 95% CI=1.11-1.38, p<0.001). Being older than 50 years, having a lower monthly income, and having hypertension, diabetes mellitus, cerebrovascular disease, chronic obstructive pulmonary disease, autoimmune disease, or osteoporosis were considered predictive factors for vertebral fracture in patients with depressive disorders. Depressive disorders may increase the risk of a subsequent new-onset vertebral fracture.

Diagnosis and Management of Vertebral Compression Fractures.

PubMed

McCarthy, Jason; Davis, Amy

2016-07-01

Vertebral compression fractures (VCFs) are the most common complication of osteoporosis, affecting more than 700,000 Americans annually. Fracture risk increases with age, with four in 10 white women older than 50 years experiencing a hip, spine, or vertebral fracture in their lifetime. VCFs can lead to chronic pain, disfigurement, height loss, impaired activities of daily living, increased risk of pressure sores, pneumonia, and psychological distress. Patients with an acute VCF may report abrupt onset of back pain with position changes, coughing, sneezing, or lifting. Physical examination findings are often normal, but can demonstrate kyphosis and midline spine tenderness. More than two-thirds of patients are asymptomatic and diagnosed incidentally on plain radiography. Acute VCFs may be treated with analgesics such as acetaminophen, nonsteroidal anti-inflammatory drugs, narcotics, and calcitonin. Physicians must be mindful of medication adverse effects in older patients. Other conservative therapeutic options include limited bed rest, bracing, physical therapy, nerve root blocks, and epidural injections. Percutaneous vertebral augmentation, including vertebroplasty and kyphoplasty, is controversial, but can be considered in patients with inadequate pain relief with nonsurgical care or when persistent pain substantially affects quality of life. Family physicians can help prevent vertebral fractures through management of risk factors and the treatment of osteoporosis.

Epithelioid hemangioendothelioma of the spine: case report and review of the literature

PubMed Central

Albakr, Abdulrahman; Schell, Miranda; Drew, Brian

2017-01-01

Epithelioid hemangioendothelioma (EHE) has been described as a rare vascular bone lesion with histological features between hemangioma and high-grade angiosarcoma. Spinal EHE is a quite rare disease with few case reports and series reported in the literature. The tumor cells are positive for vimentin, CD31and CD34, factor VIII related antigen, ERG, and FLI1. Radiological features are not specific; it may appear as an osteolytic lesion. It can present as a multifocal disease in 40% of cases. No clear correlation with age and sex; however, it is slightly more common in males. Focal neck or back pain is the most common presenting symptom. The natural history of spinal EHE is unpredictable, and currently, there is no standard of care for treatment. Treatment options include preoperative embolization, and surgical resection followed by radiotherapy and/or chemotherapy. A 34-year-old previously healthy male presented with mid-thoracic back pain. Magnetic resonance imaging (MRI) of the spine revealed a decrease in vertebral body height at T5 with an enhancing mass. He underwent T5 balloon kyphoplasty and needle vertebral body biopsy. Results of the biopsy samples were non-diagnostic. Approximately 3 months after surgery, the patient presented with unsteady gait. A subsequent MRI revealed progression of the T5 compression fracture with cord compression. The patient subsequently underwent T4–T6 bilateral posterior decompression for epidural tumor and T3–T7 posterior instrumentation with pedicle screws. Pathology of the lesion revealed EHE. The patient was started on local radiation therapy (RT). On follow-up, 3 months after the second surgery, the thoracic spinal pain had improved dramatically. Our review highlights the diagnosis, clinical presentation, and treatment of spinal EHE. Complete resection is associated with good outcome. Radiotherapy has been used in partially resected lesions. However, the role of radiotherapy as primary treatment is not yet defined. Further studies should develop a treatment algorithm for this rare tumour. PMID:28744509

Cranial thoracic vertebral canal stenosis in three juvenile large-breed brachycephalic dogs treated by unilateral hemilaminectomy.

PubMed

Miller, Amanda; Marchevsky, Andrew

2017-05-22

To describe the surgical treatment and outcome for juvenile dogs with cranial thoracic vertebral canal stenosis treated by unilateral hemilaminectomy. Case series. Three large-breed brachycephalic dogs of various breeds (Dogue de Bordeaux, Australian Bulldog, Boerboel) with neurological signs consistent with a myelopathy of the third thoracic (T) to third lumbar (L) spinal cord segment. Information on clinical presentation, diagnostic imaging, surgical procedures, postoperative complications, recovery and outcome is described. Neurological signs were present and progressive for two to four weeks prior to surgery and ranged from mild ataxia to paralysis. Cranial thoracic vertebral canal stenosis was diagnosed with computed tomography imaging. Lateral and dorsolateral spinal cord compression was present at multiple sites between T2 and T6. Alternating left and right-sided compressions were common. Surgical treatment was by unilateral, continuous hemilaminectomy over three to six vertebral spaces. Postoperative morbidity was minimal and return of independent ambulation was rapid (median: 13.5 days, range: 2-29 days). Neurological status in one dog worsened four months after surgery due to reoccurrence of osseous compression; unilateral hemilaminectomy was repeated in this dog. Long-term follow-up ranged from six to 10 months; neurological signs had completely resolved in one dog and substantially improved in the other two dogs. Unilateral hemilaminectomy was associated with rapid return of independent ambulation and substantial improvement in neurological scores.

How should clinicians manage osteoporosis in ankylosing spondylitis?

PubMed

Bessant, Rupa; Keat, Andrew

2002-07-01

Osteoporosis is a common complication of AS, with an incidence between 18.7% and 62%. The prevalence of osteoporosis is greater in males, and increases with increasing patient age and disease duration. Osteoporosis is also more common in patients with syndesmophytes, cervical fusion, and peripheral joint involvement. These variables are not all independent, as they may be indicators of disease duration. Osteoporosis in patients with AS is largely confined to the axial skeleton, in contrast to the pattern of osteoporosis seen in rheumatoid arthritis. BMD at the lumbar spine and femoral neck may be severely reduced, while most studies indicate that carpal and radial BMD remain within normal limits. The development of syndesmophytes in late AS can lead to difficulties in the use of DEXA scanning to determine lumbar BMD, as the extraspinal bone may obscure osteoporotic vertebrae. Under these circumstances more accurate assessment of lumbar BMD, and one that correlates better with femoral neck BMD, may be obtained by quantitative CT scanning or DEXA scanning of the lateral aspect of the L3 vertebra. Osteoporosis in AS significantly increases the risk of vertebral compression fractures within 5 years of the diagnosis of AS. The risk of a vertebral compression fracture occurring over a 30 year period following the diagnosis of AS is 14%, compared to 3.4% for population controls. In patients with vertebral osteoporosis relatively minor trauma, such as slipping, can lead to spinal fracture and dislocatior with subsequent damage to the spinal cord. There is a higher incidence of spinal cord injury following spinal fracture dislocations in patients with AS, and the resulting neurological deficit can range from mild sensory loss to complete paraplegia. Cytokines such as TNF-alpha and IL-6 may play an important part in the pathogenesis of osteoporosis in early AS, and IL-6 levels have been correlated with markers of disease activity and severity. In late AS, mechanical factors such as decreased mobility and the support provided by extraspinal bone may play a role in vertebral osteoporosis. Screening patients with AS for the presence of osteoporosis is an important, but contentious subject. This and subsequent monitoring needs to be considered in all patients, but longterm studies are needed to determine with confidence which patients should undergo screening, by which methods, and how often. The treatment of osteoporosis in AS is at present similar to that used for primary osteoporosis, except that due to the male predominance and a relatively young age of patients, there is a limited role for hormone replacement therapy. Exercise regimens and bisphosphonates are widely used, but a study of the relative efficacy of different bisphosphonate agents in patients with AS is required.

MRI features of cervical articular process degenerative joint disease in Great Dane dogs with cervical spondylomyelopathy.

PubMed

Gutierrez-Quintana, Rodrigo; Penderis, Jacques

2012-01-01

Cervical spondylomyelopathy or Wobbler syndrome commonly affects the cervical vertebral column of Great Dane dogs. Degenerative changes affecting the articular process joints are a frequent finding in these patients; however, the correlation between these changes and other features of cervical spondylomyelopathy are uncertain. We described and graded the degenerative changes evident in the cervical articular process joints from 13 Great Danes dogs with cervical spondylomyelopathy using MR imaging, and evaluated the relationship between individual features of cervical articular process joint degeneration and the presence of spinal cord compression, vertebral foraminal stenosis, intramedullary spinal cord changes, and intervertebral disc degenerative changes. Degenerative changes affecting the articular process joints were common, with only 13 of 94 (14%) having no degenerative changes. The most severe changes were evident between C4-C5 and C7-T1 intervertebral spaces. Reduction or loss of the hyperintense synovial fluid signal on T2-weighted MR images was the most frequent feature associated with articular process joint degenerative changes. Degenerative changes of the articular process joints affecting the synovial fluid or articular surface, or causing lateral hypertrophic tissue, were positively correlated with lateral spinal cord compression and vertebral foraminal stenosis. Dorsal hypertrophic tissue was positively correlated with dorsal spinal cord compression. Disc-associated spinal cord compression was recognized less frequently. © 2011 Veterinary Radiology & Ultrasound.

Unipedicular versus bipedicular percutaneous vertebroplasty for osteoporotic vertebral compression fractures: a prospective randomized study.

PubMed

Zhang, Liang; Liu, Zhongjun; Wang, Jingcheng; Feng, Xinmin; Yang, Jiandong; Tao, Yuping; Zhang, Shengfei

2015-06-14

Percutaneous vertebroplasty (PVP) typically involves conventional lower-viscosity cement injection via bipedicular approach. Limited evidence is available comparing the clinical outcomes and complications in treating osteoporotic vertebral compression fractures (OVCFs) with PVP using high-viscosity cement through unipedicular or bipedicular approach. Fifty patients with OVCFs were randomly allocated into two groups adopting unipedicular or bipedicular PVP. The efficacy of unipedicular and bipedicular PVP was assessed by comparing operation time, X-ray exposure time, incidence of complications, vertebral height restoration, and improvement of the visual analogue scale (VAS), Oswestry disability index (ODI) and Short Form-36 (SF-36) General Health Survey scores. The mean operative and exposure time to X-rays in the unipedicular PVP group was less than that of the bipedicular group (p < 0.05). No statistically significant differences were observed in the VAS score, ODI score, SF-36 score, cement leakage rate or vertebral height restoration between the two groups (p > 0.05). Unipedicular and bipedicular PVP are safe and effective treatments for OVCF. Compared with bipedicular PVP, unipedicular PVP entails a shorter surgical time and lower X-ray irradiation.

Frequency of Magnetic Resonance Imaging patterns of tuberculous spondylitis in a public sector hospital.

PubMed

Tabassum, Sumera; Haider, Shahbaz

2016-01-01

To determine frequencies of different MRI patterns of tuberculous spondylitisin a public sector hospital in Karachi. This descriptive multidisciplinary case series study was done from October 25, 2011 to May 28, 2012 in Radiology Department and Department of Medicine in the Jinnah Postgraduate Medical Center Karachi. MRI scans (dorsal / lumbosacral spine) of the Patients presenting with backache in Medical OPD, were performed in Radiology Department. Axial and sagittal images of T1 weighted, T2 weighted and STIR sequences of the affected region were taken. A total of 140 patients who were diagnosed as having tuberculous spondylitis were further evaluated and analyzed for having different patterns of involvement of the spine and compared with similar studies. Among frequencies of different MRI pattern of tuberculous spondylitis, contiguous vertebral involvement was 100%, discal involvement 98.6%, paravertebral abscess 92.1% cases, epidural abscess 91.4%, spinal cord / thecal sac compression 89.3%, vertebral collapse 72.9%, gibbus deformity 42.9% and psoas abscess 36.4%. Contiguous vertebral involvement was commonest MRI pattern, followed by disk involvement, paravertebral & epidural abscesses, thecal sac compression and vertebral collapse.

Acute compressive myelopathy due to vertebral haemangioma.

PubMed

Macki, Mohamed; Bydon, Mohamad; Kaloostian, Paul; Bydon, Ali

2014-04-28

A 47-year-old woman with a history of anaemia presented to the emergency room with an acute onset of leg weakness. Physical examination of the bilateral lower extremities was significant for 0/5 muscle strength in all muscle groups with decreased pinprick and temperature sensation. A sensory level at the umbilicus was appreciated. Fine touch and proprioception were preserved. Bowel and bladder function were intact. CT revealed several thoracic, vertebral haemangiomatas. An MRI was suggestive of an epidural clot at the T8-T10-weighted posterior epidural space. At the level of the lesion, the cerebrospinal fluid space was completely effaced, and the flattened spinal cord exhibited signs of oedema and compressive myelopathy. The patient immediately underwent surgical decompression of the spinal cord. An epidural clot and vessel conglomeration were identified. A postoperative spinal angiogram confirmed the diagnosis of vertebral haemangioma. At 1-month follow-up, the patient regained strength and sensation.

Acute compressive myelopathy due to vertebral haemangioma

PubMed Central

Macki, Mohamed; Bydon, Mohamad; Kaloostian, Paul; Bydon, Ali

2014-01-01

A 47-year-old woman with a history of anaemia presented to the emergency room with an acute onset of leg weakness. Physical examination of the bilateral lower extremities was significant for 0/5 muscle strength in all muscle groups with decreased pinprick and temperature sensation. A sensory level at the umbilicus was appreciated. Fine touch and proprioception were preserved. Bowel and bladder function were intact. CT revealed several thoracic, vertebral haemangiomatas. An MRI was suggestive of an epidural clot at the T8–T10-weighted posterior epidural space. At the level of the lesion, the cerebrospinal fluid space was completely effaced, and the flattened spinal cord exhibited signs of oedema and compressive myelopathy. The patient immediately underwent surgical decompression of the spinal cord. An epidural clot and vessel conglomeration were identified. A postoperative spinal angiogram confirmed the diagnosis of vertebral haemangioma. At 1-month follow-up, the patient regained strength and sensation. PMID:24777075

Coblation vertebroplasty for complex vertebral insufficiency fractures.

PubMed

Wilson, David J; Owen, Sara; Corkill, Rufus A

2013-07-01

Coblation to create a cavity in the affected vertebral body was performed for complex fractures and/or when there was a posterior wall defect. This permitted a low-pressure injection and potentially reduces the risk of extravasation of cement into the spinal canal. Prospective audit for outcome measures and complications allowed retrospective review of cases treated by coblation. A commercial wand inserted via a wide-bore vertebroplasty needle created a cavity before inserting cement. A visual analogue scale assessed pain and Roland Morris scoring assessed mobility. Thirty-two coblation procedures were performed. Primary diagnoses were myeloma, metastases, osteoporosis and trauma. Outcome measures were recorded with a 56 % success rate, 6 % no change and 32 % with mixed but mainly positive results; 6 % died before follow-up. No complications were observed; in particular no patient suffered neurological damage and none have developed subsequent fractures at the treated levels. This technique makes possible cementation of patients who would otherwise be unsuitable for vertebroplasty. The modest pain and disability improvement is partly due to our stringent criteria as well as fracture complexity. Further work will assess the efficacy of the method compared with conservative measures. • Treatment of vertebral compression fractures with possible posterior wall defects is controversial. • Coblation before vertebroplasty allows a low-pressure injection into fractured vertebrae. • This technique reduces risk of extravasation of cement. • No serious complication of our coblation procedures was observed.

Pinhole collimator scintigraphy in differential diagnosis of metastasis, fracture, and infections of the spine

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

Bahk, Y.W.; Kim, O.H.; Chung, S.K.

1987-04-01

The informational gains obtained by the use of pinhole collimator scintigraphy (PCS) have been well documented. The present study has been undertaken to prospectively investigate its efficacy in diagnosing several commonly occurring spinal diseases. Patient material consisted of metastatic cancer (39 vertebrae), compression fractures (33 vertebrae), tuberculous spondylitis (17 vertebrae), and pyogenic spondylitis (six vertebrae). PCS findings were characterized in terms of localization, appearance, and homogeneity of abnormal radionuclide accumulation. Thus, metastatic cancer manifested as diffusely or focally homogeneous accumulation within the vertebral body or as a typical short-segmental accumulation along the end-plate, whereas compression fracture manifested as characteristic board-likemore » accumulation along the entire length of end-plates. Tuberculous spondylitis, on the other hand, revealed homogeneous accumulation throughout the vertebral body, and pyogenic spondylitis revealed accumulation at the end-zone of opposing vertebral bodies giving sandwich-like appearance. The disk space at the affected level was not narrowed in the former two diseases but it was narrowed in the latter two. It was concluded that PCS may be useful in differentiating metastatic cancer, compression fracture, tuberculous spondylitis, and pyogenic spondylitis.« less

Undiagnosed vertebral hemangioma causing a lumbar compression fracture and epidural hematoma in a parturient undergoing vaginal delivery under epidural analgesia: a case report.

PubMed

Staikou, Chryssoula; Stamelos, Matthaios; Boutas, Ioannis; Koutoulidis, Vassileios

2015-08-01

Vertebral hemangiomas are benign vascular tumours of the bony spine which are usually asymptomatic. Pregnancy-related anatomical and hormonal changes may lead to expansion of hemangiomas and development of neurological symptoms. We present an unusual case of vertebral fracture due to an undiagnosed hemangioma presenting as postpartum back pain following epidural analgesia. A multiparous female with an unremarkable history developed intense lumbar pain after vaginal delivery under epidural analgesia. The pain was attributed to tissue trauma associated with the epidural technique. The patient had no clinical improvement with analgesics, and her symptoms deteriorated over the following days. A magnetic resonance imaging scan revealed an acute fracture of the second lumbar vertebra (L2) with epidural extension and mild compression of the dural sac, suggesting hemangioma as the underlying cause. The patient underwent successful spinal surgery with pedicle screw fixation to stabilize the fracture. Vertebral fractures secondary to acute expansion of a vertebral hemangioma rarely occur during vaginal delivery. In such cases, the labour epidural technique and analgesia may challenge the physician in making the diagnosis. Postpartum severe back pain should be thoroughly investigated even in the absence of neurological deficits, and osseous spinal pathology should be considered in the differential diagnosis.

[Is height restoration possible with a comparatively smaller amount of cement in radiofrequency kyphoplasty using a monopedicle approach?].

PubMed

Röllinghoff, M; Hagel, A; Siewe, J; Gutteck, N; Delank, K-S; Steinmetz, A; Zarghooni, K

2013-04-01

Percutaneous cement augmentation systems have been proven to be an effective treatment for vertebral compression fractures in the last 10 years. A special form available since 2009 is the radiofrequency kyphoplasty (RF) in which the applied energy raises the viscosity of the cement. The aim of this study is to find out if a smaller cement amount in radiofrequency kyphoplasty can also restore vertebral body height in osteoporotic vertebral compression fractures. The treatment was minimally invasive using the StabiliT® vertebral augmentation system by DFine. In a retrospective study from 2011 to January 2012, 35 patients underwent RF kyphoplasty for 49 fresh osteoporotic vertebral compression fractures. From the clinical side the parameters, demographics and pain relief using a visual analogue scale (VAS: 0 to 100 mm) were collected. For the radiological outcome the vertebral body height (anterior, mean and posterior vertebral body height with kyphosis angle) after surgery and after three months was measured and compared to the cement volume. All patients still had permanent pain on the fractured level after conservative treatment. The time from initial painful fracture to treatment was 3.0 weeks ± 1.3. Average visual analogue scale results decreased significantly from 71 ± 9.2 preoperatively to 35 ± 6.2 postoperatively (p < 0.001) and to 30 ± 5.7 (p < 0.001) after three months. With a mean cement volume in the thoracic spine of 2.9 ± 0.7 ml (1.8-4.1) and lumbar spine of 3.0 ± 0.7 ml (2.0-5.0) we had a significant vertebral body height restoration. Anterior and mean vertebral body heights significantly increased by an average of 2.3 and 3.1 mm, kyphosis angle significantly decreased with an average of 2.1° at three-month follow-up (p < 0.05). In two vertebrae (4.1 %) a minimal asymptomatic cement leakage occurred into the upper disc. In two patients (5.7 %) we had new fractures in the directly adjacent segment that were also successfully treated with radiofrequency kyphoplasty. With a mean cement volume of 3.0 ml radiofrequency kyphoplasty achieves rapid and short-term improvements of clinical symptoms with a significant restoration of vertebral body height. There was no correlation between restoration of vertebral body height and pain relief. With a cement leakage of 4.1 % RF kyphoplasty is a safe and effective minimally invasive percutaneous cement augmentation procedure. Our data confirm the higher safety described in literature for kyphoplasty in contrast to vertebroplasty. Georg Thieme Verlag KG Stuttgart · New York.

Examination of a lumbar spine biomechanical model for assessing axial compression, shear, and bending moment using selected Olympic lifts.

PubMed

Eltoukhy, Moataz; Travascio, Francesco; Asfour, Shihab; Elmasry, Shady; Heredia-Vargas, Hector; Signorile, Joseph

2016-09-01

Loading during concurrent bending and compression associated with deadlift, hang clean and hang snatch lifts carries the potential for injury to the intervertebral discs, muscles and ligaments. This study examined the capacity of a newly developed spinal model to compute shear and compressive forces, and bending moments in lumbar spine for each lift. Five male subjects participated in the study. The spine was modeled as a chain of rigid bodies (vertebrae) connected via the intervertebral discs. Each vertebral reference frame was centered in the center of mass of the vertebral body, and its principal directions were axial, anterior-posterior, and medial-lateral. The results demonstrated the capacity of this spinal model to assess forces and bending moments at and about the lumbar vertebrae by showing the variations among these variables with different lifting techniques. These results show the model's potential as a diagnostic tool.

A rare case of multiple pituitary adenomas in an adolescent Cushing disease presenting as a vertebral compression fracture.

PubMed

Song, Ji-Yeon; Mun, Sue-Jean; Sung, Soon-Ki; Hwang, Jae-Yeon; Baik, Seung-Kug; Kim, Jee Yeon; Cheon, Chong-Kun; Kim, Su-Young; Kim, Yoo-Mi

2017-09-01

Cushing disease in children and adolescents, especially with multiple pituitary adenomas (MPAs), is very rare. We report 17-year-old boy with MPAs. He presented with a vertebral compression fracture, weight gain, short stature, headache, and hypertension. On magnetic resonance imaging (MRI), only a left pituitary microadenoma was found. After surgery, transient clinical improvement was observed but headache and hypertension were observed again after 3 months later. Follow-up MRI showed a newly developed right pituitary microadenoma 6 months after the surgery. The need for careful clinical and radiographic follow-up should be emphasized in the search for potential MPAs in patients with persistent Cushing disease.

Previous vertebral compression fractures add to the deterioration of the disability and quality of life after an acute compression fracture.

PubMed

Suzuki, Nobuyuki; Ogikubo, Osamu; Hansson, Tommy

2010-04-01

Prevalent vertebral compression fracture(s) have been reported as having a negative impact on pain, disability, and quality of life. But no study has evaluated the effect of previous fracture on the course of acute compression fractures. The aim of the present study was to compare the natural course of the acute compression fracture in patients with (n = 51) and without (n = 56) previous vertebral compression fracture(s). The study is a retrospective analysis of a prospective cohort followed with postal questionnaires during a 12-month period after an acute fracture event. Eligible patients were those over 40 years of age, who were admitted to the emergency unit because of back pain and had an X-ray confirmed acute vertebral body fracture. A total of 107 patients were included in the study. The pain, disability (von Korff pain and disability scores), ADL (Hannover ADL score), and quality of life (QoL) (EQ-5D) were measured after 3 weeks, and 3, 6, and 12 months. The X-rays from the first visit to the emergency unit were evaluated. The difference of the scores between the groups with and without previous fracture was statistically significant (P < 0.05) at 3 weeks, 6 and 12 months for von Korff disability score, at all occasions for EQ-5D and at 3-12 months for Hannover ADL score, but only at 12 months for the von Korff pain intensity score. In both the groups all scores had improved in a statistically significant way at 3 months. The number of previous fractures was related to all the outcome scores in a statistically significant way (P < 0.05) except von Korff pain intensity score at 3 weeks and 3 months and von Korff disability score at 3 months. In conclusion, disability, ADL, and QoL scores, but not pain intensity score, were significantly worse in the patients with previous fracture from the fracture episode through the first 12 months. However, the improvements during the follow-up year seen in both groups were of a similar magnitude. The presence or absence of a previous fracture in an acutely fractured patient will influence the prognosis and thus possibly also the indications for treatments.

Kyphoplasty increases vertebral height, decreases both pain score and opiate requirements while improving functional status.

PubMed

Tolba, Reda; Bolash, Robert B; Shroll, Joshua; Costandi, Shrif; Dalton, Jarrod E; Sanghvi, Chirag; Mekhail, Nagy

2014-03-01

Vertebral compression fractures can result from advanced osteoporosis, or less commonly from metastatic or traumatic insults to the vertebral column, and result in disabling pain and decreased functional capacity. Various vertebral augmentation options including kyphoplasty aim at preventing the sequelae of pain and immobility that can develop as the result of the vertebral fractures. The mechanism for pain relief following kyphoplasty is not entirely understood, and the restoration of a portion of the lost vertebral height is a subject of debate. We retrospectively reviewed radiographic imaging, pain relief, analgesic intake and functional outcomes in 67 consecutive patients who underwent single- or multilevel kyphoplasty with the primary goal of quantifying the restoration of lost vertebral height. We observed a mean of 45% of the lost vertebral height restored postprocedurally. Secondarily, kyphoplasty was associated with significant decreases in pain scores, daily morphine consumption and improvement in patient-reported functional measures. © 2013 World Institute of Pain.

Stiffness of the endplate boundary layer and endplate surface topography are associated with brittleness of human whole vertebral bodies

PubMed Central

Nekkanty, Srikant; Yerramshetty, Janardhan; Kim, Do-Gyoon; Zauel, Roger; Johnson, Evan; Cody, Dianna D.; Yeni, Yener N.

2013-01-01

Stress magnitude and variability as estimated from large scale finite element (FE) analyses have been associated with compressive strength of human vertebral cancellous cores but these relationships have not been explored for whole vertebral bodies. In this study, the objectives were to investigate the relationship of FE-calculated stress distribution parameters with experimentally determined strength, stiffness, and displacement based ductility measures in human whole vertebral bodies, investigate the effect of endplate loading conditions on vertebral stiffness, strength, and ductility and test the hypothesis that endplate topography affects vertebral ductility and stress distributions. Eighteen vertebral bodies (T6-L3 levels; 4 female and 5 male cadavers, aged 40-98 years) were scanned using a flat panel CT system and followed with axial compression testing with Wood’s metal as filler material to maintain flat boundaries between load plates and specimens. FE models were constructed using reconstructed CT images and filler material was added digitally. Two different FE models with different filler material modulus simulating Wood’s metal and intervertebral disc (W-layer and D-layer models) were used. Element material modulus to cancellous bone was based on image gray value. Average, standard deviation, and coefficient of variation of von Mises stress in vertebral bone for W-layer and D-layer models and also the ratios of FE parameters from the two models (W/D) were calculated. Inferior and superior endplate surface topographical distribution parameters were calculated. Experimental stiffness, maximum load and work to fracture had the highest correlation with FE-calculated stiffness while experimental ductility measures had highest correlations with FE-calculated average von Mises stress and W-layer to D-layer stiffness ratio. Endplate topography of the vertebra was also associated with its structural ductility and the distribution parameter that best explained this association was kurtosis of inferior endplate topography. Our results indicate that endplate topography variations may provide insight into the mechanisms responsible for vertebral fractures. PMID:20633709

Investigation of biomechanical behavior of lumbar vertebral segments with dynamic stabilization device using finite element approach

NASA Astrophysics Data System (ADS)

Deoghare, Ashish B.; Kashyap, Siddharth; Padole, Pramod M.

2013-03-01

Degenerative disc disease is a major source of lower back pain and significantly alters the biomechanics of the lumbar spine. Dynamic stabilization device is a remedial technique which uses flexible materials to stabilize the affected lumbar region while preserving the natural anatomy of the spine. The main objective of this research work is to investigate the stiffness variation of dynamic stabilization device under various loading conditions under compression, axial rotation and flexion. Three dimensional model of the two segment lumbar spine is developed using computed tomography (CT) scan images. The lumbar structure developed is analyzed in ANSYS workbench. Two types of dynamic stabilization are considered: one with stabilizing device as pedicle instrumentation and second with stabilization device inserted around the inter-vertebral disc. Analysis suggests that proper positioning of the dynamic stabilization device is of paramount significance prior to the surgery. Inserting the device in the posterior region indicates the adverse effects as it shows increase in the deformation of the inter-vertebral disc. Analysis executed by positioning stabilizing device around the inter-vertebral disc yields better result for various stiffness values under compression and other loadings. [Figure not available: see fulltext.

Vertebral osteomyelitis and epidural abscess due to Aspergillus nidulans resulting in spinal cord compression: case report and literature review.

PubMed

Jiang, Zheng; Wang, Yunyan; Jiang, Yuquan; Xu, Yonghao; Meng, Bin

2013-04-01

Vertebral osteomyelitis caused by Aspergillus nidulans is rare and usually affects immunocompromised patients. This report presents a case of thoracic vertebral osteomyelitis with epidural abscesses due to A. nidulans in a 40-year-old immunocompetent female who presented with back pain, numbness and weakness of both lower limbs. Magnetic resonance imaging demonstrated osteomyelitis involving the thoracic (T)1-T3 vertebral bodies with epidural abscesses, resulting in spinal compression. The patient underwent a decompression laminectomy of T1-T3 and debridement of the thoracic epidural inflammatory granuloma. Histopathology revealed fungal granulomatous inflammation. The patient received 6 mg/kg voriconazole every 12 h (loading dose on day 1) followed by 4 mg/kg voriconazole twice daily for 1 month, administered intravenously. The patient returned with recurrent back pain 16 months after initial presentation. A. nidulans was identified by fungal culture and polymerase chain reaction. The patient showed no evidence of recurrence 1 year after a 6-month course of oral voriconazole. The key to the effective treatment of Aspergillus osteomyelitis is not to excise the abscess, but to administer systemic antifungal drug therapy.

Treatment of spinal fractures with paraplegia.

PubMed

Riska, E B; Myllynen, P

1981-01-01

Of 206 patients with vertebral fractures in the thoraco-lumbar spine with spinal cord injuries, an antero-lateral decompression with stabilization of the injured segment of the vertebral column was undertaken in 56 cases. In all these cases there was a compression of the spinal cord from the front. 8 patients made a complete recovery, 31 a good recovery, and 6 were improved. In 8 patients no improvement was noted. 2 patients developed pressure sores later and 1 patient died one year after the operation of uraemia. 22 patients out of 55 got a normal function of the bladder and 25 patients out of 54 a normal function of the anal sphincter. 16 patients out of 17 made a complete or good recovery after removal of a displaced rotated vertebral bony fragment from the spinal canal, and 7 patients out of 9 with wedge shaped fractures. In our clinic today, in cases of vertebral fractures with neural involvement, reduction and internal fixation with Harrington rods and fusion of the injured segment is undertaken as soon as possible, also during the night. If narrowing of the neural canal and compression of the spinal cord are verified, a decompression operation with interbody fusion is undertaken during the next days.

Comparison the clinical outcomes and complications of high-viscosity versus low-viscosity in osteoporotic vertebral compression fractures.

PubMed

Guo, Zhao; Wang, Wei; Gao, Wen-Shan; Gao, Fei; Wang, Hui; Ding, Wen-Yuan

2017-12-01

To compare the clinical outcomes and complications of high viscosity and low viscosity bone cement percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCF).From September 2009 to September 2015, 100 patients with OVCF were randomly divided into 2 groups: group H, using high viscosity cement (n = 50) or group L, using low viscosity cement (n = 50). The clinical outcomes were assessed by the visual analog scale (VAS), Oswestry Disability Index (ODI), kyphosis Cobb angle, vertebral height, and complications.Significant improvements in the VAS, ODI, kyphosis Cobb angle, and vertebral height were noted in both groups, and the VAS score in the H group showed greater benefit than in the L group. Cement leakage was observed less in group H. Postoperative assessment using computed tomography identified cement leakage in 27 of 98 (27.6%) vertebrae in group H and in 63 of 86 (73.3%) vertebrae in group L (P = .025).Compared with PVP using low viscosity bone cement, PVP using high viscosity bone cement can provide the same clinical outcomes with fewer complications and is recommended for routine clinical use.

Comparison the clinical outcomes and complications of high-viscosity versus low-viscosity in osteoporotic vertebral compression fractures

PubMed Central

Guo, Zhao; Wang, Wei; Gao, Wen-shan; Gao, Fei; Wang, Hui; Ding, Wen-Yuan

2017-01-01

Abstract To compare the clinical outcomes and complications of high viscosity and low viscosity bone cement percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCF). From September 2009 to September 2015, 100 patients with OVCF were randomly divided into 2 groups: group H, using high viscosity cement (n = 50) or group L, using low viscosity cement (n = 50). The clinical outcomes were assessed by the visual analog scale (VAS), Oswestry Disability Index (ODI), kyphosis Cobb angle, vertebral height, and complications. Significant improvements in the VAS, ODI, kyphosis Cobb angle, and vertebral height were noted in both groups, and the VAS score in the H group showed greater benefit than in the L group. Cement leakage was observed less in group H. Postoperative assessment using computed tomography identified cement leakage in 27 of 98 (27.6%) vertebrae in group H and in 63 of 86 (73.3%) vertebrae in group L (P = .025). Compared with PVP using low viscosity bone cement, PVP using high viscosity bone cement can provide the same clinical outcomes with fewer complications and is recommended for routine clinical use. PMID:29310386

Frequency of Magnetic Resonance Imaging patterns of tuberculous spondylitis in a public sector hospital

PubMed Central

Tabassum, Sumera; Haider, Shahbaz

2016-01-01

Objective: To determine frequencies of different MRI patterns of tuberculous spondylitisin a public sector hospital in Karachi. Methods: This descriptive multidisciplinary case series study was done from October 25, 2011 to May 28, 2012 in Radiology Department and Department of Medicine in the Jinnah Postgraduate Medical Center Karachi. MRI scans (dorsal / lumbosacral spine) of the Patients presenting with backache in Medical OPD, were performed in Radiology Department. Axial and sagittal images of T1 weighted, T2 weighted and STIR sequences of the affected region were taken. A total of 140 patients who were diagnosed as having tuberculous spondylitis were further evaluated and analyzed for having different patterns of involvement of the spine and compared with similar studies. Results: Among frequencies of different MRI pattern of tuberculous spondylitis, contiguous vertebral involvement was 100%, discal involvement 98.6%, paravertebral abscess 92.1% cases, epidural abscess 91.4%, spinal cord / thecal sac compression 89.3%, vertebral collapse 72.9%, gibbus deformity 42.9% and psoas abscess 36.4%. Conclusion: Contiguous vertebral involvement was commonest MRI pattern, followed by disk involvement, paravertebral & epidural abscesses, thecal sac compression and vertebral collapse. PMID:27022369

ADC as a useful diagnostic tool for differentiating benign and malignant vertebral bone marrow lesions and compression fractures: a systematic review and meta-analysis.

PubMed

Suh, Chong Hyun; Yun, Seong Jong; Jin, Wook; Lee, Sun Hwa; Park, So Young; Ryu, Chang-Woo

2018-07-01

To assess the sensitivity and specificity of quantitative assessment of the apparent diffusion coefficient (ADC) for differentiating benign and malignant vertebral bone marrow lesions (BMLs) and compression fractures (CFs) METHODS: An electronic literature search of MEDLINE and EMBASE was conducted. Bivariate modelling and hierarchical summary receiver operating characteristic modelling were performed to evaluate the diagnostic performance of ADC for differentiating vertebral BMLs. Subgroup analysis was performed for differentiating benign and malignant vertebral CFs. Meta-regression analyses according to subject, study and diffusion-weighted imaging (DWI) characteristics were performed. Twelve eligible studies (748 lesions, 661 patients) were included. The ADC exhibited a pooled sensitivity of 0.89 (95% confidence interval [CI] 0.80-0.94) and a pooled specificity of 0.87 (95% CI 0.78-0.93) for differentiating benign and malignant vertebral BMLs. In addition, the pooled sensitivity and specificity for differentiating benign and malignant CFs were 0.92 (95% CI 0.82-0.97) and 0.91 (95% CI 0.87-0.94), respectively. In the meta-regression analysis, the DWI slice thickness was a significant factor affecting heterogeneity (p < 0.01); thinner slice thickness (< 5 mm) showed higher specificity (95%) than thicker slice thickness (81%). Quantitative assessment of ADC is a useful diagnostic tool for differentiating benign and malignant vertebral BMLs and CFs. • Quantitative assessment of ADC is useful in differentiating vertebral BMLs. • Quantitative ADC assessment for BMLs had sensitivity of 89%, specificity of 87%. • Quantitative ADC assessment for CFs had sensitivity of 92%, specificity of 91%. • The specificity is highest (95%) with thinner (< 5 mm) DWI slice thickness.

Mechanical Loading during Growth Is Associated with Plane-specific Differences in Vertebral Geometry: A Cross-sectional Analysis Comparing Artistic Gymnasts vs. Non-gymnasts

PubMed Central

Dowthwaite, Jodi N.; Rosenbaum, Paula F.; Scerpella, Tamara A.

2011-01-01

Lumbar spine geometry, density and indices of bone strength were assessed relative to menarche status, using artistic gymnastics exposure during growth as a model of mechanical loading. Paired posteroanterior (PA) and supine lateral (LAT) DXA scans of L3 for 114 females (60 ex/gymnasts and 54 non-gymnasts) yielded output for comparison of paired (PALAT) versus standard PA and LAT outcomes. BMC, areal BMD, vertebral body dimensions, bone mineral apparent density (BMAD), axial compressive strength (IBS) and a fracture risk index were evaluated, modeling vertebral body geometry as an ellipsoid cylinder. Two-factor ANCOVA tested statistical effects of gymnastic exposure, menarche status and their interaction, adjusting for age and height as appropriate. Compared to non-gymnasts, ex/gymnasts exhibited greater PABMD, PABMC, PAWIDTH, PA CROSS-SECTIONAL AREA (CSA), PAVOLUME, LATBMD, LATBMAD, PALATCSA and PALATIBS (p<0.05). Non-gymnasts exhibited greater LATDEPTH/PAWIDTH, LATBMC/PABMC, LATVHEIGHT, LATAREA and Fracture Risk Index. Using ellipsoid vertebral geometric models, no significant differences were detected for PA or PALAT BMAD. In contrast, cuboid model results (Carter 1992) suggested erroneous ex/gymnast PABMAD advantages, resulting from invalid assumptions of proportional variation in linear skeletal dimensions. Gymnastic exposure was associated with shorter, wider vertebral bodies, yielding greater axial compressive strength and lower fracture risk, despite no BMAD advantage. Our results suggest the importance of plane-specific vertebral geometric adaptation to mechanical loading during growth. Paired scan output provides a more accurate assessment of this adaptation than PA or LAT plane scans alone. PMID:21839871

Analysis of Vertebral Bone Strength, Fracture Pattern, and Fracture Location: A Validation Study Using a Computed Tomography-Based Nonlinear Finite Element Analysis

PubMed Central

Imai, Kazuhiro

2015-01-01

Finite element analysis (FEA) is an advanced computer technique of structural stress analysis developed in engineering mechanics. Because the compressive behavior of vertebral bone shows nonlinear behavior, a nonlinear FEA should be utilized to analyze the clinical vertebral fracture. In this article, a computed tomography-based nonlinear FEA (CT/FEA) to analyze the vertebral bone strength, fracture pattern, and fracture location is introduced. The accuracy of the CT/FEA was validated by performing experimental mechanical testing with human cadaveric specimens. Vertebral bone strength and the minimum principal strain at the vertebral surface were accurately analyzed using the CT/FEA. The experimental fracture pattern and fracture location were also accurately simulated. Optimization of the element size was performed by assessing the accuracy of the CT/FEA, and the optimum element size was assumed to be 2 mm. It is expected that the CT/FEA will be valuable in analyzing vertebral fracture risk and assessing therapeutic effects on osteoporosis. PMID:26029476

Development and evolution of the vertebrate primary mouth

PubMed Central

Soukup, Vladimír; Horácek, Ivan; Cerny, Robert

2013-01-01

The vertebrate oral region represents a key interface between outer and inner environments, and its structural and functional design is among the limiting factors for survival of its owners. Both formation of the respective oral opening (primary mouth) and establishment of the food-processing apparatus (secondary mouth) require interplay between several embryonic tissues and complex embryonic rearrangements. Although many aspects of the secondary mouth formation, including development of the jaws, teeth or taste buds, are known in considerable detail, general knowledge about primary mouth formation is regrettably low. In this paper, primary mouth formation is reviewed from a comparative point of view in order to reveal its underestimated morphogenetic diversity among, and also within, particular vertebrate clades. In general, three main developmental modes were identified. The most common is characterized by primary mouth formation via a deeply invaginated ectodermal stomodeum and subsequent rupture of the bilaminar oral membrane. However, in salamander, lungfish and also in some frog species, the mouth develops alternatively via stomodeal collar formation contributed both by the ecto- and endoderm. In ray-finned fishes, on the other hand, the mouth forms via an ectoderm wedge and later horizontal detachment of the initially compressed oral epithelia with probably a mixed germ-layer derivation. A very intriguing situation can be seen in agnathan fishes: whereas lampreys develop their primary mouth in a manner similar to the most common gnathostome pattern, hagfishes seem to undergo a unique oropharyngeal morphogenesis when compared with other vertebrates. In discussing the early formative embryonic correlates of primary mouth formation likely to be responsible for evolutionary–developmental modifications of this area, we stress an essential role of four factors: first, positioning and amount of yolk tissue; closely related to, second, endoderm formation during gastrulation, which initiates the process and constrains possible evolutionary changes within this area; third, incipient structure of the stomodeal primordium at the anterior neural plate border, where the ectoderm component of the prospective primary mouth is formed; and fourth, the prime role of Pitx genes for establishment and later morphogenesis of oral region both in vertebrates and non-vertebrate chordates. PMID:22804777

Characterization of synthetic foam structures used to manufacture artificial vertebral trabecular bone.

PubMed

Fürst, David; Senck, Sascha; Hollensteiner, Marianne; Esterer, Benjamin; Augat, Peter; Eckstein, Felix; Schrempf, Andreas

2017-07-01

Artificial materials reflecting the mechanical properties of human bone are essential for valid and reliable implant testing and design. They also are of great benefit for realistic simulation of surgical procedures. The objective of this study was therefore to characterize two groups of self-developed synthetic foam structures by static compressive testing and by microcomputed tomography. Two mineral fillers and varying amounts of a blowing agent were used to create different expansion behavior of the synthetic open-cell foams. The resulting compressive and morphometric properties thus differed within and also slightly between both groups. Apart from the structural anisotropy, the compressive and morphometric properties of the synthetic foam materials were shown to mirror the respective characteristics of human vertebral trabecular bone in good approximation. In conclusion, the artificial materials created can be used to manufacture valid synthetic bones for surgical training. Further, they provide novel possibilities for studying the relationship between trabecular bone microstructure and biomechanical properties. Copyright © 2017 Elsevier B.V. All rights reserved.

[Vertebral artery dissection due to the C6 transverse process and laryngeal cartilage associated with vertebral artery anomaly].

PubMed

Kusunoki Nakamoto, Fumiko; Hashimoto Maeda, Meiko; Mori, Kentaro; Hara, Takayuki; Uesaka, Yoshikazu

2014-01-01

A 52-year-old woman complained of the sudden onset of a left temporal headache, left neck stiffness and dizziness. Brain magnetic resonance imaging showed a high-intensity lesion in the right medial medulla. Dynamic cerebral angiography revealed vertebral artery dissection and compression at the C6 level due to a transverse process at the C6 level associated with rightward head rotation. Removal of bone and decompression of the vertebral artery were performed from the C5 to C6 levels. Intraoperasively, obstruction of blood flow due to a laryngeal cartilage that rotated with the passive rotation of the patient's head to the right was found. To the best of our knowledge this is the first reported case of vertebral artery occlusion due to a laryngeal cartilage associated with head rotation.

Symptomatic vertebral hemangioma in pregnancy treated antepartum. A case report with review of literature.

PubMed

Vijay, Kamath; Shetty, Ajoy P; Rajasekaran, S

2008-09-01

Pregnancy related compressive myelopathy secondary to vertebral hemangioma is a rare occurrence and its treatment antepartum is rare. We report a 22-year-old lady in her 26th-week of pregnancy who was treated in two stages--antepartum with a laminectomy and posterior stabilization. This resulted in complete recovery of the neurological deficits. She delivered a normal baby after 3 months, following which a corpectomy and fusion was performed. This two-staged approach appears safe and effective in treating symptomatic vertebral haemangiomas causing neurological deficits during pregnancy. A review of relevant literature has been done.

Whiplash syndrome: kinematic factors influencing pain patterns.

PubMed

Cusick, J F; Pintar, F A; Yoganandan, N

2001-06-01

The overall, local, and segmental kinematic responses of intact human cadaver head-neck complexes undergoing an inertia-type rear-end impact were quantified. High-speed, high-resolution digital video data of individual facet joint motions during the event were statistically evaluated. To deduce the potential for various vertebral column components to be exposed to adverse strains that could result in their participation as pain generators, and to evaluate the abnormal motions that occur during this traumatic event. The vertebral column is known to incur a nonphysiologic curvature during the application of an inertial-type rear-end impact. No previous studies, however, have quantified the local component motions (facet joint compression and sliding) that occur as a result of rear-impact loading. Intact human cadaver head-neck complexes underwent inertia-type rear-end impact with predominant moments in the sagittal plane. High-resolution digital video was used to track the motions of individual facet joints during the event. Localized angular motion changes at each vertebral segment were analyzed to quantify the abnormal curvature changes. Facet joint motions were analyzed statistically to obtain differences between anterior and posterior strains. The spine initially assumed an S-curve, with the upper spinal levels in flexion and the lower spinal levels in extension. The upper C-spine flexion occurred early in the event (approximately 60 ms) during the time the head maintained its static inertia. The lower cervical spine facet joints demonstrated statistically greater compressive motions in the dorsal aspect than in the ventral aspect, whereas the sliding anteroposterior motions were the same. The nonphysiologic kinematic responses during a whiplash impact may induce stresses in certain upper cervical neural structures or lower facet joints, resulting in possible compromise sufficient to elicit either neuropathic or nociceptive pain. These dynamic alterations of the upper level (occiput to C2) could impart potentially adverse forces to related neural structures, with subsequent development of a neuropathic pain process. The pinching of the lower facet joints may lead to potential for local tissue injury and nociceptive pain.

Computerized method for detection of vertebral fractures on lateral chest radiographs based on morphometric data

NASA Astrophysics Data System (ADS)

Kasai, Satoshi; Li, Feng; Shiraishi, Junji; Li, Qiang; Straus, Christopher; Vokes, Tamara; MacMahon, Heber; Doi, Kunio

2007-03-01

Vertebral fractures are the most common osteoporosis-related fractures. It is important to detect vertebral fractures, because they are associated with increased risk of subsequent fractures, and because pharmacologic therapy can reduce the risk of subsequent fractures. Although vertebral fractures are often not clinically recognized, they can be visualized on lateral chest radiographs taken for other purposes. However, only 15-60% of vertebral fractures found on lateral chest radiographs are mentioned in radiology reports. The purpose of this study was to develop a computerized method for detection of vertebral fractures on lateral chest radiographs in order to assist radiologists' image interpretation. Our computerized method is based on the automated identification of upper and lower vertebral edges. In order to develop the scheme, radiologists provided morphometric data for each identifiable vertebra, which consisted of six points for each vertebra, for 25 normals and 20 cases with severe fractures. Anatomical information was obtained from morphometric data of normal cases in terms of vertebral heights, heights of vertebral disk spaces, and vertebral centerline. Computerized detection of vertebral fractures was based on the reduction in the heights of fractured vertebrae compared to adjacent vertebrae and normal reference data. Vertebral heights from morphometric data on normal cases were used as reference. On 138 chest radiographs (20 with fractures) the sensitivity of our method for detection of fracture cases was 95% (19/20) with 0.93 (110/118) false-positives per image. In conclusion, the computerized method would be useful for detection of potentially overlooked vertebral fractures on lateral chest radiographs.

Practical use of bone scan in patients with an osteoporotic vertebral compression fracture.

PubMed

Jun, Deuk Soo; An, Byoung Keun; Yu, Chang Hun; Hwang, Kyung Hoon; Paik, Je Won

2015-02-01

Rib fractures are one of main causes of chest or flank pain when related to an osteoporotic vertebral compression fracture (OVCF). The authors investigated the incidence and risk factors of rib fracture in 284 patients with OVCF using bone scans and evaluated the feasibility as to whether bone scans could be utilized as a useful screening tool. Hot uptake lesions on ribs were found in 122 cases (43.0%). The factors analyzed were age, sex, number and locations of fractured vertebrae, BMD, and compression rates as determined using initial radiography. However, no statistical significances were found. In 16 cases (5.6%), there were concurrent multiple fractures of both the thoracic and lumbar spines not detected by single site MRI. Sixty cases (21.1%) of OVCF with the a compression rate of less than 15% could not be identified definitely by initial plain radiography, but were confirmed by bone scans. It is concluded that a bone scan has outstanding ability for the screening of rib fractures associated with OVCF. Non-adjacent multiple fractures in both thoracic and lumbar spines and fractures not identified definitely by plain radiography were detected on bone scans, which provided a means for determining management strategies and predicting prognosis.

Vertebral Artery Dissection Causing Stroke After Trampoline Use.

PubMed

Casserly, Courtney S; Lim, Rodrick K; Prasad, Asuri Narayan

2015-11-01

The aim of this study was to report a case of a 4-year-old boy who had been playing on the trampoline and presented to the emergency department (ED) with vomiting and ataxia, and had a vertebral artery dissection with subsequent posterior circulation infarcts. This study is a chart review. The patient presented to the emergency department with a 4-day history of vomiting and gait unsteadiness. A computed tomography scan of his head revealed multiple left cerebellar infarcts. Subsequent magnetic resonance imaging/magnetic resonance angiogram of his head and neck demonstrated multiple infarcts involving the left cerebellum, bilateral thalami, and left occipital lobe. A computed tomography angiogram confirmed the presence of a left vertebral artery dissection. Vertebral artery dissection is a relatively common cause of stroke in the pediatric age group. Trampoline use has been associated with significant risk of injury to the head and neck. Patients who are small and/or young are most at risk. In this case, minor trauma secondary to trampoline use could be a possible mechanism for vertebral artery dissection and subsequent strokes. The association in this case warrants careful consideration because trampoline use could pose a significant risk to pediatric users.

Vertebral Compression Fractures

MedlinePlus

... and monitored to avoid putting pressure on the ribs that can cause new fractures. Surgical Procedures • When there is severe incapacitating pain • When healing is delayed or when bone fragments ...

A comparative study of high-viscosity cement percutaneous vertebroplasty vs. low-viscosity cement percutaneous kyphoplasty for treatment of osteoporotic vertebral compression fractures.

PubMed

Sun, Kai; Liu, Yang; Peng, Hao; Tan, Jun-Feng; Zhang, Mi; Zheng, Xian-Nian; Chen, Fang-Zhou; Li, Ming-Hui

2016-06-01

The clinical effects of two different methods-high-viscosity cement percutaneous vertebroplasty (PVP) and low-viscosity cement percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral compression fractures (OVCFs) were investigated. From June 2010 to August 2013, 98 cases of OVCFs were included in our study. Forty-six patients underwent high-viscosity PVP and 52 patients underwent low-viscosity PKP. The occurrence of cement leakage was observed. Pain relief and functional activity were evaluated using the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI), respectively. Restoration of the vertebral body height and angle of kyphosis were assessed by comparing preoperative and postoperative measurements of the anterior heights, middle heights and the kyphotic angle of the fractured vertebra. Nine out of the 54 vertebra bodies and 11 out of the 60 vertebra bodies were observed to have cement leakage in the high-viscosity PVP and low-viscosity PKP groups, respectively. The rate of cement leakage, correction of anterior vertebral height and kyphotic angles showed no significant differences between the two groups (P>0.05). Low-viscosity PKP had significant advantage in terms of the restoration of middle vertebral height as compared with the high-viscosity PVP (P<0.05). Both groups showed significant improvements in pain relief and functional capacity status after surgery (P<0.05). It was concluded that high-viscosity PVP and low-viscosity PKP have similar clinical effects in terms of the rate of cement leakage, restoration of the anterior vertebral body height, changes of kyphotic angles, functional activity, and pain relief. Low-viscosity PKP is better than high-viscosity PVP in restoring the height of the middle vertebra.

Vertebral Compression Fractures after Lumbar Instrumentation.

PubMed

Granville, Michelle; Berti, Aldo; Jacobson, Robert E

2017-09-29

Lumbar spinal stenosis (LSS) is primarily found in an older population. This is a similar demographic group that develops both osteoporosis and vertebral compression fractures (VCF). This report reviewed a series of patients treated for VCF that had previous lumbar surgery for symptomatic spinal stenosis. Patients that only underwent laminectomy or fusion without instrumentation had a similar distribution of VCF as the non-surgical population in the mid-thoracic, or lower thoracic and upper lumbar spine. However, in the patients that had previous short-segment spinal instrumentation, fractures were found to be located more commonly in the mid-lumbar spine or sacrum adjacent to or within one or two spinal segments of the spinal instrumentation. Adjacent-level fractures that occur due to vertebral osteoporosis after long spinal segment instrumentation has been discussed in the literature. The purpose of this report is to highlight the previously unreported finding of frequent lumbar and sacral osteoporotic fractures in post-lumbar instrumentation surgery patients. Important additional factors found were lack of preventative medical treatment for osteoporosis, and secondary effects related to inactivity, especially during the first year after surgery.

Fat embolism syndrome following percutaneous vertebroplasty: a case report.

PubMed

Ahmadzai, Hasib; Campbell, Scott; Archis, Constantine; Clark, William A

2014-04-01

Vertebroplasty is commonly performed for management of pain associated with vertebral compression fractures. There have been two previous reports of fatal fat embolism following vertebroplasty. Here we describe a case of fat embolism syndrome following this procedure, and also provide fluoroscopic video evidence consistent with this occurrence. The purpose of this study was to review the literature and report a case of fat embolism syndrome in a patient who underwent percutaneous vertebroplasty for compression fracture. The study design for this manuscript was of a clinical case report. A 68-year-old woman who developed sudden back pain with minimal trauma was found to have a T6 vertebral compression fracture on radiographs and bone scans. Percutaneous vertebroplasty of T5 and T6 was performed. Fluoroscopic imaging during the procedure demonstrated compression and rarefaction of the fractured vertebra associated with changes in intrathoracic pressure. Immediately after the procedure, the patient's back pain resolved and she was discharged home. Two days later, she developed increasing respiratory distress, confusion, and chest pain. A petechial rash on her upper arms also appeared. No evidence of bone cement leakage or pulmonary filling defects were seen on computed tomography-pulmonary angiography. Brain magnetic resonance imaging demonstrated hyperintensities in the periventricular and subcortical white matter on T2/fluid-attenuated inversion recovery sequences. A diagnosis of fat embolism syndrome was made, and the patient recovered with conservative management. Percutaneous vertebroplasty is a relatively safe and simple procedure, reducing pain and improving functional limitations in patients with vertebral fractures. This case demonstrates an uncommon yet serious complication of fat embolism syndrome. Clinicians must be aware of this complication when explaining the procedure to patients and provide prompt supportive care when it does occur. Copyright © 2014 Elsevier Inc. All rights reserved.

Symptomatic vertebral hemangioma in pregnancy treated antepartum. A case report with review of literature

PubMed Central

Vijay, Kamath; Shetty, Ajoy P.

2008-01-01

Pregnancy related compressive myelopathy secondary to vertebral hemangioma is a rare occurrence and its treatment antepartum is rare. We report a 22-year-old lady in her 26th-week of pregnancy who was treated in two stages––antepartum with a laminectomy and posterior stabilization. This resulted in complete recovery of the neurological deficits. She delivered a normal baby after 3 months, following which a corpectomy and fusion was performed. This two-staged approach appears safe and effective in treating symptomatic vertebral haemangiomas causing neurological deficits during pregnancy. A review of relevant literature has been done. PMID:18224354

The role of physical activity in bone health: a new hypothesis to reduce risk of vertebral fracture.

PubMed

Sinaki, Mehrsheed

2007-08-01

Locomotion has always been a major criterion for human survival. Thus, it is no surprise that science supports the dependence of bone health on weight-bearing physical activities. The effect of physical activity on bone is site-specific. Determining how to perform osteogenic exercises, especially in individuals who have osteopenia or osteoporosis, without exceeding the biomechanical competence of bone always poses a dilemma and must occur under medical advice. This article presents the hypothesis that back exercises performed in a prone position, rather than a vertical position, may have a greater effect on decreasing the risk for vertebral fractures without resulting in compression fracture. The risk for vertebral fractures can be reduced through improvement in the horizontal trabecular connection of vertebral bodies.

Preventive effects of conservative treatment with short-term teriparatide on the progression of vertebral body collapse after osteoporotic vertebral compression fracture.

PubMed

Park, J-H; Kang, K-C; Shin, D-E; Koh, Y-G; Son, J-S; Kim, B-H

2014-02-01

The progression of fractured vertebral collapse is not rare after a conservative treatment of vertebral compression fracture (VCF). Teriparatide has been shown to directly stimulate bone formation and improve bone density, but there is a lack of evidence regarding its use in fracture management. Conservative treatment with short-term teriparatide is effective for decreasing the progression of fractured vertebral body collapse. Few studies have reported on the prevention of collapsed vertebral body progression after osteoporotic VCF. Teriparatide rapidly enhances bone formation and increases bone strength. This study evaluated preventive effects of short-term teriparatide on the progression of vertebral body collapse after osteoporotic VCF. Radiographs of 68 women with single-level osteoporotic VCF at thoracolumbar junction (T11-L2) were reviewed. Among them, 32 patients were treated conservatively with teriparatide (minimum 3 months) (group I), and 36 were treated with antiresorptive (group II). We measured kyphosis and wedge angle of the fractured vertebral body, and ratios of anterior, middle, and posterior heights of the collapsed body to posterior height of a normal upper vertebra were determined. The degree of collapse progression was compared between two groups. The progression of fractured vertebral body collapse was shown in both groups, but the degree of progression was significantly lower in group I than in group II. At the last follow-up, mean increments of kyphosis and wedge angle were significantly lower in group I (4.0° ± 4.2° and 3.6° ± 3.6°) than in group II (6.8° ± 4.1° and 5.8° ± 3.5°) (p = 0.032 and p = 0.037). Decrement percentages of anterior and middle border height were significantly lower in group I (9.6 ± 10.3 and 7.4 ± 7.5 %) than in group II (18.1 ± 9.7 and 13.8 ± 12.2 %) (p = 0.001 and p = 0.025), but not in posterior height (p = 0.086). In female patients with single-level osteoporotic VCF at the thoracolumbar junction, short-term teriparatide treatment did not prevent but did decrease the progression of fractured vertebral body collapse.

Vertebral fracture after aircraft ejection during Operation Desert Storm.

PubMed

Osborne, R G; Cook, A A

1997-04-01

During Operation Desert Storm, 21 United States and 2 Italian military personnel were held in Iraq as prisoners of war. Of these, 18 had ejected from fixed-wing, ejection seat-equipped, combat aircraft prior to their capture. Of the 18, 6 (33%) had sustained vertebral fractures; 4 of these were compression fractures. This fracture rate is comparable to that of previously studied groups. Fractures were noted to be at several different vertebral sites and after ejecting from a variety of aircraft. Apart from contusions and abrasions, vertebral fractures were the most common injuries discovered in this repatriated population. None of the vertebral fractures produced recognizable neurological disability. The development of vertebral fractures was neither associated with the use of any particular ejection system or aircraft nor did the development of vertebral fractures appear dependent on the age, height or length of service of the affected personnel. Ejected aircrew with low altitude mission profiles seemed more predisposed to vertebral fracture than those at high altitudes, but with a small sample population, this relationship was not statistically significant (p > 0.25). Reliable data were unavailable on aircrew positioning and preparation time for ejection.

Mortality in the Vertebroplasty Population

PubMed Central

McDonald, Robert J.; Achenbach, Sara; Atkinson, Elizabeth; Gray, Leigh A.; Cloft, Harry J.; Melton, L. Joseph; Kallmes, David F.

2011-01-01

Purpose Vertebroplasty is an effective treatment for painful compression fractures refractory to conservative management. Since there are limited data regarding the survival characteristics of this patient population, we compared the survival of a treated to an untreated vertebral fracture cohort to determine if vertebroplasty affects mortality rates. Materials and Methods The survival of a treated cohort, comprising 524 vertebroplasty recipients with refractory osteoporotic vertebral compression fractures, was compared to a separate, historical cohort of 589 subjects with fractures not treated by vertebroplasty who were identified from the Rochester Epidemiology Project. Mortality was compared between cohorts using Cox proportional hazard models adjusting for age, gender, and Charlson indices of co-morbidity. Mortality was also correlated with pre-, peri-, and post-procedural clinical metrics (e.g., cement volume utilization, Roland-Morris Disability Questionnaire score, analog pain scales, frequency of narcotic use, and improvements in mobility) within the treated cohort. Results Vertebroplasty recipients demonstrated 77% of the survival expected for individuals of similar age, ethnicity, and gender within the US population. When compared to individuals with both symptomatic and asymptomatic untreated vertebral fractures, vertebroplasty recipients retained a 17% greater mortality risk. However, when compared to symptomatic untreated vertebral fractures, vertebroplasty recipients had no increased mortality following adjustment for differences in age, sex and co-morbidity (HR 1.02; CI 0.82–1.25). In addition, no clinical metrics used to assess the efficacy of vertebroplasty were predictive of survival. Conclusion Vertebroplasty recipients have mortality rates similar to individuals with untreated symptomatic fractures but worse mortality compared to those with asymptomatic vertebral fractures. PMID:21998109

Analysis of Long Bone and Vertebral Failure Patterns.

DTIC Science & Technology

1982-03-01

Roberts, B., 1976. Pathology of degenerative spondylosis in The Lumbar Spine and Back Pain (ed. M. Jayson), New York, Grune & Stratton, Inc., pp. 55-75...compressive loading failed by end plate or vertebral body fracture (Percy, 1957). The fractures were most common in the upper lumbar level, and the fracture...and upper lumbar regions which is supported Iby Perey’s findings (1957). The debris in the hematopoietic spaces appears Ito be bone fragments, but it

Percutaneous balloon kyphoplasty for the treatment of vertebral compression fractures

PubMed Central

2014-01-01

Background Vertebral compression fractures (VCFs) constitute a major health care problem, not only because of their high incidence but also because of their direct and indirect negative impacts on both patients’ health-related quality of life and costs to the health care system. Two minimally invasive surgical approaches were developed for the management of symptomatic VCFs: balloon kyphoplasty and vertebroplasty. The purpose of this study was to evaluate the effectiveness and safety of balloon kyphoplasty in the treatment of symptomatic VCFs. Methods Between July 2011 and June 2012, one hundred and eighty-seven patients with two hundred and fifty-one vertebras received balloon kyphoplasty in our hospital. There were sixty-five male and one hundred and twenty-two female patients with an average age of 74.5 (range, 61 to 95 years). The pain symptoms and quality of life, were measured before operation and at one day, three months, six months and one year following kyphoplasty. Radiographic data including restoration of kyphotic angle, anterior vertebral height, and any leakage of cement were defined. Results The mean visual analog pain scale decreased from a preoperative value of 7.7 to 2.2 at one day (p < .05) following operation and the Oswestry Disability Index improved from 56.8 to 18.3 (p < .05). The kyphotic angle improved from a mean of 14.4° before surgery to 6.7° at one day after surgery (p < .05). The mean anterior vertebral height increased significantly from 52% before surgery to 74.5% at one day after surgery (p < .05) and 70.2% at one year follow-up. Minor cement extravasations were observed in twenty-nine out of two hundred and fifty-one procedures, including six leakage via basivertebral vein, three leakage via segmental vein and twenty leakage through a cortical defect. None of the leakages were associated with any clinical consequences. Conclusions Balloon kyphoplasty not only rapidly reduced pain and disability but also restored sagittal alignment in our patients at one-year follow-up. The treatment of osteoporotic vertebral compression fractures with balloon kyphoplasty is a safe, effective, and minimally invasive procedure that provides satisfactory clinical results. PMID:24423182

A new hero emerges: another exceptional mammalian spine and its potential adaptive significance.

PubMed

Stanley, William T; Robbins, Lynn W; Malekani, Jean M; Mbalitini, Sylvestre Gambalemoke; Migurimu, Dudu Akaibe; Mukinzi, Jean Claude; Hulselmans, Jan; Prévot, Vanya; Verheyen, Erik; Hutterer, Rainer; Doty, Jeffrey B; Monroe, Benjamin P; Nakazawa, Yoshinori J; Braden, Zachary; Carroll, Darin; Peterhans, Julian C Kerbis; Bates, John M; Esselstyn, Jacob A

2013-10-23

The hero shrew's (Scutisorex somereni) massive interlocking lumbar vertebrae represent the most extreme modification of the vertebral column known in mammals. No intermediate form of this remarkable morphology is known, nor is there any convincing theory to explain its functional significance. We document a new species in the heretofore monotypic genus Scutisorex; the new species possesses cranial and vertebral features representing intermediate character states between S. somereni and other shrews. Phylogenetic analyses of DNA sequences support a sister relationship between the new species and S. somereni. While the function of the unusual spine in Scutisorex is unknown, it gives these small animals incredible vertebral strength. Based on field observations, we hypothesize that the unique vertebral column is an adaptation allowing these shrews to lever heavy or compressive objects to access concentrated food resources inaccessible to other animals.

Thoracolumbar vertebral osteochondroma in a young dog.

PubMed

Santen, D R; Payne, J T; Pace, L W; Kroll, R A; Johnson, G C

1991-10-15

Osteosarcoma was diagnosed in a 7-month-old female German Shepherd Dog with hind limb paresis. Radiography revealed a circumscribed calcified mass in the dorsal vertebral lamina at T13-L1 resulting in extradural compression of the spinal cord. Surgical excision of the mass resulted in gradual return to normal neurologic function. Four weeks after surgery, the dog became severely atactic after rolling onto its back. A chip fracture of T13 was identified, and the dog was euthanatized at the owners' request.

Left hemibody myoclonus due to anomalous right vertebral artery.

PubMed

Coelho, Miguel; Marti, Maria J; Valls-Solé, Josep; Pujol, Teresa; Tolosa, Eduardo

2005-01-01

A 43-year-old man presented with sporadic, sudden, brief, and involuntary jerks of his left limbs and trunk muscles. The electromyographic recordings showed short-lasting highly synchronized bursts, compatible with myoclonus limited to the left hemibody. Blink reflex, masseter silent period, cortical and spinal magnetic stimulation, somatosensory cortical evoked potentials, and electroencephalogram (EEG) were normal; the EEG back-averaging showed no spikes preceding the myoclonus. Magnetic resonance imaging and magnetic resonance angiography showed the presence of an anomalous nonectasic right vertebral artery compressing the right side of ventral medulla oblongata. We hypothesize that the aberrant right vertebral artery induced abnormal activation of descending motor tracts responsible for the myoclonus. (c) 2004 Movement Disorder Society.

Comparative review of vertebroplasty and kyphoplasty

PubMed Central

Ruiz Santiago, Fernando; Santiago Chinchilla, Alicia; Guzmán Álvarez, Luis; Pérez Abela, Antonio Luis; Castellano García, Maria del Mar; Pajares López, Miguel

2014-01-01

The aim of this review is to compare the effectiveness of percutaneous vertebroplasty and kyphoplasty to treat pain and improve functional outcome from vertebral fractures secondary to osteoporosis and tumor conditions. In 2009, two open randomized controlled trials published in the New England Journal of Medicine questioned the value of vertebroplasty in treating vertebral compression fractures. Nevertheless, the practice of physicians treating these conditions has barely changed. The objective of this review is to try to clarify the most important issues, based on our own experience and the reported evidence about both techniques, and to guide towards the most appropriate choice of treatment of vertebral fractures, although many questions still remain unanswered. PMID:24976934

Isolated unilateral vertebral pedicle fracture caused by a back massage in an elderly patient: a case report and literature review.

PubMed

Guo, Zhiping; Chen, Wei; Su, Yanling; Yuan, Junhui; Zhang, Yingze

2013-11-01

The vertebral pedicle injuries are clinically common. However, the isolated vertebral pedicle fracture with intact vertebral bodies is a rare lesion. We reported a case of a 66-year-old man who experienced a pedicle fracture after a back massage. The patient sustained osteoporosis, long-existing low back pain and nerve compression symptoms without antecedent major trauma. Imaging findings demonstrated an isolated unilateral L5 vertebral pedicle fracture with intact vertebral bodies, spinal canal stenosis at the L4-5 levels, bulging annulus fibrosus at the L4-S1 levels, bilateral spondylolysis and an L5/S1 spondylolisthesis. The patient underwent L4-S1 decompressive laminectomy, L5/S1 discectomy and neurolysis, and reduction and fixation of the L5 vertebral pedicle fracture and L5/S1 spondylolisthesis using the pedicle nail system. At follow-ups, the patient showed good recovery without pain or numbness in the low back and bilateral lower extremities. This study raises the awareness of a complication of alternative medicine and the possibility of a pedicle fracture caused by a low-energy trauma.

Osteosynthesis system for vertebra arthrodesis

DOEpatents

Ameil, Marc; Huppert, Jean; Jermann, Jean-Louis; Marnay, Thierry

2000-01-01

An osteosynthesis system for vertebral arthrodesis, having at least one vertebral compression or distraction bar capable of extending over a portion at least of the rachis; at least one vertebral anchoring member having an end head with a spherical surface, an intermediate shank and a vertebral anchoring portion; and, associated with each anchoring member, a common support for receiving, coupling and immobilizing the vertebral anchoring member and the bar, the common support including a first concave housing for receiving the bar, a second concave housing, for receiving the spherical head, and a screwthreaded member, for immobilization of the bar and the anchoring member on the support, the immobilization member having at least one nut which is screwed onto a screwthreaded portion of the support. The first housing is disposed to the exterior of the screwthreaded portion of the support and is open laterally and upwardly, in opposite relationship to the rachis, so that the bar is immobilized by a peripheral portion of the nut.

Effects of glucocorticoids on skeletal growth in rabbits evaluated by dual-photon absorptiometry, microscopic connectivity and vertebral compressive strength.

PubMed

Grardel, B; Sutter, B; Flautre, B; Viguier, E; Lavaste, F; Hardouin, P

1994-07-01

The effects of corticosteroid on bone were examined in female growing rabbits treated with 0.7 mg/kg per day prednisolone for 5 months. The evolution of whole-body total bone mineral measured by dual-photon absorptiometry showed a significant difference between the prednisolone-treated group and the control group from the first to the fifth month. The histomorphometric profile of corticosteroid-induced osteoporosis was observed, in particular the lower bone volume and thinner and fewer trabecular plates. Mechanical tests are possible on rabbit vertebrae and showed a very significant difference in bone strength between the prednisolone-treated and control groups, and a good correlation between mechanical tests and histomorphometric or densitometric results. This bone corticosteroid model shows that vertebral compression tests are possible on rabbit lumbar vertebrae. It may contribute to a better evaluation of corticosteroid treatments.

Total spondylectomy of a symptomatic hemangioma of the lumbar spine.

PubMed

Inoue, Toshiyuki; Miyamoto, Kei; Kodama, Hirotaka; Hosoe, Hideo; Shimizu, Katsuji

2007-08-01

A vertebral hemangioma with dural compression and neurological deficit is rare. We report a symptomatic lumbar vertebral hemangioma which was successfully managed with total spondylectomy. The patient was a 31-year-old man whose chief complaint was low back pain. He had a slight sensory disturbance in the right thigh. Plain radiography and magnetic resonance imaging (MRI) revealed a tumor in the second lumbar vertebra, which extended into the spinal canal, compressing the dura. A percutaneous needle biopsy did not provide a pathological diagnosis. Before surgery, the arteries feeding the tumor were embolized using coils. We performed a total spondylectomy of the second lumbar vertebra with anterior reconstruction with a glass ceramic spacer and posterior instrumentation. The intraoperative pathological examination revealed a hemangioma of the lumbar spine. At the 4-year follow-up examination, the patient is completely asymptomatic without evidence of tumor recurrence.

A review of complications associated with vertebroplasty and kyphoplasty as reported to the Food and Drug Administration medical device related web site.

PubMed

Nussbaum, David A; Gailloud, Philippe; Murphy, Kieran

2004-11-01

In 2002, approximately 38,000 vertebroplasties and 16,000 kyphoplasties were performed in the United States. As the use of both modalities for the treatment of vertebral compression fractures has increased, so have questions regarding safety and efficacy. The authors addressed this by reviewing both the current literature and complications data reported to the Food and Drug Administration (FDA) Center for Devices and Radiological Health through the on-line database (http://www.fda.gov/cdrh/maude.html) and through the Office of the Freedom of Information Act at the FDA. Although both procedures are largely safe, the FDA data highlight two main concerns: reactions to the use of acrylic (polymethylmethacrylate) bone cement, including hypotension and, in some cases, death, especially when multiple vertebral levels are treated in one setting; and a possible increased risk with kyphoplasty of pedicle fracture and cord compression.

[Initial clinical experience with radiofrequency-guided percutaneous vertebral augmentation in the treatment of vertebral compression fractures].

PubMed

Marosfoi, Miklós; Kulcsár, Zsolt; Berentei, Zsolt; Gubucz, István; Szikora, István

2011-07-30

Percutaenous Vertebroplasty (PVP) is effective in alleviating pain and facilitating early mobilization following vertebral compression fractures. The relatively high risk of extravertebral leakage due to uncontrolled delivery of low viscosity bone cement is an inherent limitation of the technique. The aim of this research is to investigate the ability of controlled cement delivery in decreasing the rate of such complications by applying radiofrequency heating to regulate cement viscosity. Thirty two vetebrae were treated in 28 patients as part of an Ethics Committee approved multicenter clinical trial using RadioFreqency assisted Percutaenous Vertebral Augmentation (RF-PVA) technique. This technique is injecting low viscosity polymethylmethacrylate (PMMA) bone cement using a pressure controlled hydraulic pump and applying radiofrequency heating to increase cement viscosity prior to entering the vertebral body. All patients were screened for any cement leakage by X-ray and CT scan. The intensity of pain was recorded on a Visual Analog Scale (VAS) and the level of physical activity on the Oswestry Disability Index (ODI) prior to, one day, one month and three months following procedure. All procedures were technically successful. There were no clinical complication, intraspinal or intraforaminal cement leakage. In nine cases (29%) a small amount of PMMA entered the intervertebral space through the broken end plate. Intensity of pain by VAS was reduced from a mean of 7.0 to 2.5 and physical inactivity dropped on the ODI from 52% to 23% three months following treatment. In this small series controlled cement injection using RF-PVA was capable of preventing clinically hazardous extravertebral cement leakage while achieving outcomes similar to that of conventional vertebroplasty.

Biomechanical Comparison of Locking Compression Plate versus Positive Profile Pins and Polymethylmethacrylate for Stabilization of the Canine Lumbar Vertebrae.

PubMed

Sturges, Beverly K; Kapatkin, Amy S; Garcia, Tanya C; Anwer, Cona; Fukuda, Shimpei; Hitchens, Peta L; Wisner, Tristan; Hayashi, Kei; Stover, Susan M

2016-04-01

To compare the stiffness, angular deformation, and mode of failure of lumbar vertebral column constructs stabilized with bilateral pins and polymethylmethacrylate (Pin-PMMA) or with a unilateral (left) locking compression plate (LCP) with monocortical screws. Ex vivo biomechanical, non-randomized. Cadaveric canine thoracolumbar specimens (n=16). Thoracolumbar (T13-L3) vertebral specimens had the L1-L2 vertebral motion unit stabilized with either Pin-PMMA or LCP. Stiffness in flexion, extension, and right and left lateral bending after nondestructive testing were compared between intact (pretreated) specimens and Pin-PMMA, and LCP constructs. The Pin-PMMA and LCP constructs were then tested to failure in flexion and left lateral bending. Both the Pin-PMMA and LCP constructs had reduced range of motion at the stabilized L1-L2 vertebral motion unit compared to intact specimens. The Pin-PMMA constructs had less range of motion for the flexion elastic zone than LCP constructs. The Pin-PMMA constructs were stiffer than intact specimens in flexion, extension, and lateral bending, and stiffer than LCP constructs in flexion and left lateral bending. The Pin-PMMA constructs had less angular deformation at construct yield and lower residual deformation at L1-L2 than LCP constructs after destructive testing to failure in flexion. The Pin-PMMA constructs were stiffer, stronger, and had less deformation at yield than LCP constructs after destructive testing to failure in lateral bending. Most constructs failed distant to the implant and fixation site. Pin-PMMA constructs had greater lumbar vertebral stiffness and reduced ROM than LCP constructs; however, both Pin-PMMA and LCP constructs were stronger than intact specimens. © Copyright 2016 by The American College of Veterinary Surgeons.

Stronger back muscles reduce the incidence of vertebral fractures: a prospective 10 year follow-up of postmenopausal women.

PubMed

Sinaki, M; Itoi, E; Wahner, H W; Wollan, P; Gelzcer, R; Mullan, B P; Collins, D A; Hodgson, S F

2002-06-01

The long-term protective effect of stronger back muscles on the spine was determined in 50 healthy white postmenopausal women, aged 58-75 years, 8 years after they had completed a 2 year randomized, controlled trial. Twenty-seven subjects had performed progressive, resistive back-strengthening exercises for 2 years and 23 had served as controls. Bone mineral density, spine radiographs, back extensor strength, biochemical marker values, and level of physical activity were obtained for all subjects at baseline, 2 years, and 10 years. Mean back extensor strength (BES) in the back-exercise (BE) group was 39.4 kg at baseline, 66.8 kg at 2 years (after 2 years of prescribed exercises), and 32.9 kg at 10 years (8 years after cessation of the prescribed exercises). Mean BES in the control (C) group was 36.9 kg at baseline, 49.0 kg at 2 years, and 26.9 kg at 10 years. The difference between the two groups was still statistically significant at 10 year follow-up (p = 0.001). The difference in bone mineral density, which was not significant between the two groups at baseline and 2 year follow-up, was significant at 10 year follow-up (p = 0.0004). The incidence of vertebral compression fracture was 14 fractures in 322 vertebral bodies examined (4.3%) in the C group and 6 fractures in 378 vertebral bodies examined (1.6%) in the BE group (chi-square test, p = 0.0290). The relative risk for compression fracture was 2.7 times greater in the C group than in the BE group. To our knowledge, this is the first study reported in the literature demonstrating the long-term effect of strong back muscles on the reduction of vertebral fractures in estrogen-deficient women.

Collagen type XI alpha1 may be involved in the structural plasticity of the vertebral column in Atlantic salmon (Salmo salar L.).

PubMed

Wargelius, A; Fjelldal, P G; Nordgarden, U; Grini, A; Krossøy, C; Grotmol, S; Totland, G K; Hansen, T

2010-04-01

Atlantic salmon (Salmo salar L.) vertebral bone displays plasticity in structure, osteoid secretion and mineralization in response to photoperiod. Other properties of the vertebral bone, such as mineral content and mechanical strength, are also associated with common malformations in farmed Atlantic salmon. The biological mechanisms that underlie these changes in bone physiology are unknown, and in order to elucidate which factors might be involved in this process, microarray assays were performed on vertebral bone of Atlantic salmon reared under natural or continuous light. Eight genes were upregulated in response to continuous light treatment, whereas only one of them was upregulated in a duplicate experiment. The transcriptionally regulated gene was predicted to code for collagen type XI alpha1, a protein known to be involved in controlling the diameter of fibrillar collagens in mammals. Furthermore, the gene was highly expressed in the vertebrae, where spatial expression was found in trabecular and compact bone osteoblasts and in the chordoblasts of the notochordal sheath. When we measured the expression level of the gene in the tissue compartments of the vertebrae, the collagen turned out to be 150 and 25 times more highly expressed in the notochord and compact bone respectively, relative to the expression in the trabecular bone. Gene expression was induced in response to continuous light, and reduced in compressed vertebrae. The downregulation in compressed vertebrae was due to reduced expression in the compact bone, while expression in the trabecular bone and the notochord was unaffected. These data support the hypothesis that this gene codes for a presumptive collagen type XI alpha1, which may be involved in the regulatory pathway leading to structural adaptation of the vertebral architecture.

Quantitative computed tomography-based predictions of vertebral strength in anterior bending.

PubMed

Buckley, Jenni M; Cheng, Liu; Loo, Kenneth; Slyfield, Craig; Xu, Zheng

2007-04-20

This study examined the ability of QCT-based structural assessment techniques to predict vertebral strength in anterior bending. The purpose of this study was to compare the abilities of QCT-based bone mineral density (BMD), mechanics of solids models (MOS), e.g., bending rigidity, and finite element analyses (FE) to predict the strength of isolated vertebral bodies under anterior bending boundary conditions. Although the relative performance of QCT-based structural measures is well established for uniform compression, the ability of these techniques to predict vertebral strength under nonuniform loading conditions has not yet been established. Thirty human thoracic vertebrae from 30 donors (T9-T10, 20 female, 10 male; 87 +/- 5 years of age) were QCT scanned and destructively tested in anterior bending using an industrial robot arm. The QCT scans were processed to generate specimen-specific FE models as well as trabecular bone mineral density (tBMD), integral bone mineral density (iBMD), and MOS measures, such as axial and bending rigidities. Vertebral strength in anterior bending was poorly to moderately predicted by QCT-based BMD and MOS measures (R2 = 0.14-0.22). QCT-based FE models were better strength predictors (R2 = 0.34-0.40); however, their predictive performance was not statistically different from MOS bending rigidity (P > 0.05). Our results suggest that the poor clinical performance of noninvasive structural measures may be due to their inability to predict vertebral strength under bending loads. While their performance was not statistically better than MOS bending rigidities, QCT-based FE models were moderate predictors of both compressive and bending loads at failure, suggesting that this technique has the potential for strength prediction under nonuniform loads. The current FE modeling strategy is insufficient, however, and significant modifications must be made to better mimic whole bone elastic and inelastic material behavior.

Adjacent vertebral body fracture following vertebroplasty with polymethylmethacrylate or calcium phosphate cement: biomechanical evaluation of the cadaveric spine.

PubMed

Nouda, Shinya; Tomita, Seiji; Kin, Akihiro; Kawahara, Kunihiko; Kinoshita, Mitsuo

2009-11-15

A biomechanical study using human cadaveric thoracolumbar spinal columns. To compare the effect of treatment by vertebroplasty (VP) with polymethylmethacrylate cement and VP with calcium phosphate cement on the creation of adjacent vertebral body fracture following VP. Adjacent vertebral body fractures have been reported as a complication following VP. Twenty-four spinal columns (T10-L2) from human cadavers were subjected to dual energy radiograph absorptiometry to assess bone mineral density. They were divided into the P group and C group, and experimental vertebral compression fractures were created at T12 vertebrae. T12 vertebrae were augmented with polymethylmethacrylate and calcium phosphate cement in the P group and C group, respectively. Each spinal column was compressed until a new fracture occurred at any vertebra, and the location of newly fractured vertebra and failure load was investigated. There was no significant difference in bone mineral density at each level within each group. In the P group, a new fracture occurred at T10 in 2 specimens, T11 in 8, and L1 in 2. In the C group, it occurred at T10 in 1 specimen, T11 in 2, L1 in 1, and T12 (treated vertebra) in 8. The failure loads of the spinal column were 1774.8+/-672.3 N and 1501.2+/-556.5 N in the P group and C group, respectively. There was no significant difference in the failure load of the spinal column between each group. New vertebral fractures occurred at the vertebra adjacent to augmented vertebrae in the P group and in the augmented vertebrae in the C group. The difference in the fractured site may be because of the difference in strength between the 2 bone filler materials. Therefore, the strength of bone filler materials is considered a risk factor in developing adjacent vertebral body fractures after VP.

The evolutionary history of vertebrate cranial placodes II. Evolution of ectodermal patterning.

PubMed

Schlosser, Gerhard; Patthey, Cedric; Shimeld, Sebastian M

2014-05-01

Cranial placodes are evolutionary innovations of vertebrates. However, they most likely evolved by redeployment, rewiring and diversification of preexisting cell types and patterning mechanisms. In the second part of this review we compare vertebrates with other animal groups to elucidate the evolutionary history of ectodermal patterning. We show that several transcription factors have ancient bilaterian roles in dorsoventral and anteroposterior regionalisation of the ectoderm. Evidence from amphioxus suggests that ancestral chordates then concentrated neurosecretory cells in the anteriormost non-neural ectoderm. This anterior proto-placodal domain subsequently gave rise to the oral siphon primordia in tunicates (with neurosecretory cells being lost) and anterior (adenohypophyseal, olfactory, and lens) placodes of vertebrates. Likewise, tunicate atrial siphon primordia and posterior (otic, lateral line, and epibranchial) placodes of vertebrates probably evolved from a posterior proto-placodal region in the tunicate-vertebrate ancestor. Since both siphon primordia in tunicates give rise to sparse populations of sensory cells, both proto-placodal domains probably also gave rise to some sensory receptors in the tunicate-vertebrate ancestor. However, proper cranial placodes, which give rise to high density arrays of specialised sensory receptors and neurons, evolved from these domains only in the vertebrate lineage. We propose that this may have involved rewiring of the regulatory network upstream and downstream of Six1/2 and Six4/5 transcription factors and their Eya family cofactors. These proteins, which play ancient roles in neuronal differentiation were first recruited to the dorsal non-neural ectoderm in the tunicate-vertebrate ancestor but subsequently probably acquired new target genes in the vertebrate lineage, allowing them to adopt new functions in regulating proliferation and patterning of neuronal progenitors. Copyright © 2014 Elsevier Inc. All rights reserved.

Paraplegia in a Bornean orangutan (Pongo pygmaeus pygmaeus) due to multiple myeloma.

PubMed

Mauel, Susanne; Fritsch, Guido; Ochs, Andreas; Koch, Martin; Kershaw, Olivia; Gruber, Achim D

2009-10-01

A 38-year-old male Bornean orangutan (Pongo pygmaeus pygmaeus) developed progressive hind leg paresis. A computed tomography scan of the vertebral column revealed soft tissue type densities within vertebral bones. At necropsy infiltrating tumor masses were found in the vertebral bodies, protruding into the spinal canal and compressing the spinal cord. Microscopically neoplastic plasma cells infiltrated the vertebral bodies and adjacent soft tissues. Immunohistochemically, tumor cells tested positive for B cell markers (CD38, CD79alpha), kappa, and lambda light chains, while vimentin, GFAP, S100, and CD138 were not expressed. The tumor was classified as multiple myeloma on the basis of radiographic, pathological, and immunohistochemical findings. This first systematic case description on multiple myeloma in a non-human primate revealed many similarities with the disease in humans and the immunohistochemical tools proved suitable for their use in the orangutan.

Anomalous vertebral artery origins: the first and second reports of two variants.

PubMed

Hsu, Daniel P; Alexander, Ashley D; Gilkeson, Robert C

2010-06-01

We present two cases of aberrant origins of vertebral arteries. Case 1 is of a patient undergoing evaluation of an infrarenal aortic aneurysm stent graft. Computed tomography (CT) angiogram revealed an aberrant right vertebral artery that subsequently joined a second right vertebral artery that had the typical origin off the right subclavian artery. This represents an unusual anatomic variation not previously reported in the literature. Case 2 is of a patient being evaluated for thoracic aorta injury. CT angiogram of the chest revealed a five-vessel aortic arch with aberrant origin of the bilateral vertebral arteries distal to the left subclavian artery.

The effect of screw tunnels on the biomechanical stability of vertebral body after pedicle screws removal: a finite element analysis.

PubMed

Liu, Jia-Ming; Zhang, Yu; Zhou, Yang; Chen, Xuan-Yin; Huang, Shan-Hu; Hua, Zi-Kai; Liu, Zhi-Li

2017-06-01

Posterior reduction and pedicle screw fixation is a widely used procedure for thoracic and lumbar vertebrae fractures. Usually, the pedicle screws would be removed after the fracture healing and screw tunnels would be left. The aim of this study is to evaluate the effect of screw tunnels on the biomechanical stability of the lumbar vertebral body after pedicle screws removal by finite element analysis (FEA). First, the CT values of the screw tunnels wall in the fractured vertebral bodies were measured in patients whose pedicle screws were removed, and they were then compared with the values of vertebral cortical bone. Second, an adult patient was included and the CT images of the lumbar spine were harvested. Three dimensional finite element models of the L1 vertebra with unilateral or bilateral screw tunnels were created based on the CT images. Different compressive loads were vertically acted on the models. The maximum loads which the models sustained and the distribution of the force in the different parts of the models were recorded and compared with each other. The CT values of the tunnels wall and vertebral cortical bone were 387.126±62.342 and 399.204±53.612, which were not statistically different (P=0.149). The models of three dimensional tetrahedral mesh finite element of normal lumbar 1 vertebra were established with good geometric similarity and realistic appearance. After given the compressive loads, the cortical bone was the first one to reach its ultimate stress. The maximum loads which the bilateral screw tunnels model, unilateral screw tunnel model, and normal vertebral model can sustain were 3.97 Mpa, 3.83 Mpa, and 3.78 Mpa, respectively. For the diameter of the screw tunnels, the model with a diameter of 6.5 mm could sustain the largest load. In addition, the stress distributing on the outside of the cortical bone gradually decreased as the thickness of the tunnel wall increased. Based on the FEA, pedicle screw tunnels would not decrease the biomechanical stability and strength of the vertebral body. A large diameter of screw tunnel and thick tunnel wall were helpful for the biomechanical stability of the vertebral body.

Spinal bone marrow necrosis with vertebral compression fracture: differentiation of BMN from AVN.

PubMed

Nix, J S; Fitzgerald, R T; Samant, R S; Harrison, M; Angtuaco, E J

2014-09-01

Bone marrow necrosis (BMN) is a rare malignancy-associated hematologic disorder characterized by necrosis of myeloid and stromal marrow elements with preservation of cortical bone. Overlap between the imaging appearances of BMN and avascular necrosis (AVN) raises the potential for diagnostic confusion. We report a case of BMN presenting with a traumatic multi-level vertebral body collapse, and finding that may potentially confound distinction between the two entities. We discuss important pathophysiologic, clinical, and radiologic differences between BMN and AVN with emphasis on features important in the differential diagnosis.

Macrovascular Decompression of Facial Nerve With Anteromedial Transposition of a Dolichoectatic Vertebral Artery: 3-Dimensional Operative Video.

PubMed

Tabani, Halima; Yousef, Sonia; Burkhardt, Jan-Karl; Gandhi, Sirin; Benet, Arnau; Lawton, Michael T

2018-05-21

Most cranial nerve compression syndromes (ie, trigeminal neuralgia and hemifacial spasm) are caused by small arteries impinging on a nerve and are relieved by microvascular decompression. Rarely, cranial nerve compression syndromes can be caused by large artery impingement and can be relieved by macrovascular decompression. When present, this compression often occurs in association with degenerative atherosclerosis in the vertebral arteries (VA) and basilar artery. Conservative treatment is recommended for mild forms, but surgical transposition of the VA away from the root entry zone (REZ) can be considered. This video demonstrates macrovascular decompression of a dolichoectatic VA in a 74-yr-old female with refractory left hemifacial spasm. After obtaining IRB approval, patient consent was sought for the procedure. With the patient in three-quarter-prone position, a far-lateral craniotomy was performed. The dentate ligament was cut to free the VA, and the suprahypoglossal portion of the vagoaccessory triangle was widened. VA compressed the REZ of the facial nerve, but was mobilized anteromedially off the REZ. A muslin sling was wrapped around the VA and its tail brought down to the clival dura, which was punctured with a 19-gauge needle and enlarged with a dissector. The sling was pulled anteromedially to this puncture site and secured to the dura with an aneurysm clip, relieving the REZ of all compression. The patient tolerated the procedure with mild, transient hoarseness and her hemifacial spasm resolved completely. This case demonstrates the macrovascular decompression technique with anteromedial transposition of the vertebrobasilar artery, which can also be used for trigeminal neuralgia.

The Role of Unilateral Balloon Kyphoplasty for the Treatment of Patients with OVCFS: A Systematic Review and Meta-Analysis.

PubMed

Xiang, Guang-Heng; Tong, Min-Ji; Lou, Chao; Zhu, Si-Pin; Guo, Wei Jun; Ke, Chen Rong

2018-05-01

An increasing number of studies have been conducted to apply unilateral balloon kyphoplasty in the treatment of ostroporotic vertebral compression fractures (OVCFs). However, the efficacy and safety of unilateral kyphoplasty and whether a unilateral or a bilateral approach is superior is controversial. The purpose of this study was to evaluate the role of unilateral balloon kyphoplasty and use meta-analysis to compare the efficacy and safety of unilateral and bilateral kyphoplasty in patients with OVCFs. A systematic literature search was conducted from 1970 to April 2017 using Medline database and the Cochrane Central Register of Controlled Trials. Articles were limited to those published in English. Randomized controlled trials and nonrandomized comparative studies were also included. The following search terms were used: "osteoporotic vertebral compression fractures," or "OVCF," and "unilateral kyphoplasty," or "unipedicular approach," or "single balloon kyphoplasty," or "one balloon kyphoplasty." A comprehensive search of reference lists of retrieved articles and previous published reviews was also performed to ensure inclusion of all possible studies. All potential articles were independently reviewed by 2 investigators for inclusion into the final analysis. MINORS score was used for nonrandomized studies, and Detsky quality index was applied for prospective randomized controlled trials. Systematic review and meta-analysis was performed for the included studies. After unilateral balloon kyphoplasty the mean postoperative visual analog score (VAS) was from 1.74 to 4.77, mean postoperative kyphotic angle was from 5.9º to 11.22º, and complications involving cement leaks was from 6.8 to 21.9% or adjacent level fractures was from 0 to 5.6%). Unilateral kyphoplasty had significantly lower operative time, and less bone cement volume; however, the postoperative VAS, Oswestry Disability Index (ODI), vertebral height restoration rate, and cement leakage and adjacent vertebral fracture rate, were similar to bilateral kyphoplasty. Only 6 randomized controlled trials and 3 retrospective comparative studies were selected for analysis. Heterogeneity was detected among the studies when we pooled the outcomes. Based on the available evidence, the clinical and radiological results of unilateral balloon kyphoplasty were as good as those of bilateral balloon kyphoplasty for the treatment of OVCFs. And unilateral kyphoplasty had advantages in terms of operation time, radiation exposure, and cost. Unilateral balloon kyphoplasty, bilateral balloon kyphoplasty, osteoporotic vertebral compression fractures, complications of balloon kyphoplasty, meta-analysis.

The incidence of secondary vertebral fracture of vertebral augmentation techniques versus conservative treatment for painful osteoporotic vertebral fractures: a systematic review and meta-analysis.

PubMed

Song, Dawei; Meng, Bin; Gan, Minfeng; Niu, Junjie; Li, Shiyan; Chen, Hao; Yuan, Chenxi; Yang, Huilin

2015-08-01

Percutaneous vertebroplasty (PVP) and balloon kyphoplasty (BKP) are minimally invasive and effective vertebral augmentation techniques for managing osteoporotic vertebral compression fractures (OVCFs). Recent meta-analyses have compared the incidence of secondary vertebral fractures between patients treated with vertebral augmentation techniques or conservative treatment; however, the inclusions were not thorough and rigorous enough, and the effects of each technique on the incidence of secondary vertebral fractures remain unclear. To perform an updated systematic review and meta-analysis of the studies with more rigorous inclusion criteria on the effects of vertebral augmentation techniques and conservative treatment for OVCF on the incidence of secondary vertebral fractures. PubMed, MEDLINE, EMBASE, SpringerLink, Web of Science, and the Cochrane Library database were searched for relevant original articles comparing the incidence of secondary vertebral fractures between vertebral augmentation techniques and conservative treatment for patients with OVCFs. Randomized controlled trials (RCTs) and prospective non-randomized controlled trials (NRCTs) were identified. The methodological qualities of the studies were evaluated, relevant data were extracted and recorded, and an appropriate meta-analysis was conducted. A total of 13 articles were included. The pooled results from included studies showed no statistically significant differences in the incidence of secondary vertebral fractures between patients treated with vertebral augmentation techniques and conservative treatment. Subgroup analysis comparing different study designs, durations of symptoms, follow-up times, races of patients, and techniques were conducted, and no significant differences in the incidence of secondary fractures were identified (P > 0.05). No obvious publication bias was detected by either Begg's test (P = 0.360 > 0.05) or Egger's test (P = 0.373 > 0.05). Despite current thinking in the field that vertebral augmentation procedures may increase the incidence of secondary fractures, we found no differences in the incidence of secondary fractures between vertebral augmentation techniques and conservative treatment for patients with OVCFs. © The Foundation Acta Radiologica 2014.

Cervical vertebral erosion caused by bilateral vertebral artery tortuosity, predisposing to spinal, sprain: A medieval case study.

PubMed

Darton, Yves

2014-03-01

Bone resorption within the cervical spine due to vertebral arterial tortuosities is rarely observed in medical practice because the condition often lacks clinical symptoms. Traumatic complications involving the vertebral arteries are relatively common and occasionally very serious, but very few affect bone, appearing only when survival has been sufficiently long for a pseudoaneurysm to form. CT scans and MRI screening, practised increasingly today following traffic and sports accidents, incidentally show that arterial tortuosities that had stimulated bone resorption are relatively frequent. Only rarely do such tortuosities cause nerve compression or trigger orthopaedic problems, while large pseudoaneurysms and congenital absence of a vertebral pedicle may require surgery to stabilize the spine. There are few publications by palaeopathologists reporting such conditions of the cervical vertebrae. This contribution reports a case of a tiered bilateral tortuosity of the vertebral artery dating from the Early Middle Ages; it provides a basis by which to recognize this type of lesion in osteoarchaeology, and it attests to the fact that multiple tortuosities may lead to spinal instability in the form of spine sprain. Copyright © 2013 Elsevier Inc. All rights reserved.

Vertebral body clinico-morphological features following percutaneous vertebroplasty versus the conservatory approach.

PubMed

Constantin, Cristian; Albulescu, Dana Maria; Diţă, Daniel Răzvan; Georgescu, Claudia Valentina; Deaconu, Andrei Constantin

2018-01-01

Most percutaneous vertebroplasty procedures are being performed in order to relieve pain in patients with severe osteoporosis and associated stable fractures of one or more vertebral bodies. In addition, vertebroplasty is also recommended for patients suffering from post-traumatic symptoms associated with vertebral fractures, patients with large angiomas positioned inside the vertebral body, with an increased risk for collapse fracture and also patients presenting with pain associated with vertebral body metastatic disease. On another aspect, it is possible that in isolated cases, an orthopedic surgeon confronted with a vertebra plana presentation will recommend bone cement injection into the vertebral bodies adjacent to the fractured one, in order to have a better and more robust substrate for placement of screws or other fixation devices. The aim of our study is to compare results attained by the Department of Interventional Radiology, in performing this procedure, with results attained by following the classical orthopedic treatment procedure, involving non-operative treatment, using medication and bracing varying from simple extension orthoses in order to limit spinal flexion, light bracing for contiguous fractures, presenting either angulation or compression, and for severe cases standard thoracolumbosacral orthoses (TLSOs).

Strength of the cervical spine in compression and bending.

PubMed

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

2007-07-01

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

Osteoporosis of the slender smoker. Vertebral compression fractures and loss of metacarpal cortex in relation to postmenopausal cigarette smoking and lack of obesity.

PubMed

Daniell, H W

1976-03-01

A group of thirty-eight women under age 70 who sustained vertebral compression fractures during minor trauma included more postmenopausal smokers than a group of 34 similar women with fractures resulting from major trauma and more than a group of 572 other women. Advanced idiopathic osteoporosis occurring before age 65 was found rarely among nonsmokers. The percent cortical area at the second metacarpal midpoint was measured in 103 white women aged 40 to 49 years, and 208 white women aged 60 to 69 years. In the younger group, no quantitative differences were demonstrated between bones of the obese and the nonobese or between smokers and nonsmokers. In contrast, among the older group, postmenopausal smokers exhibited much more bone loss than did nonsmokers (P less than .001), and nonobese women demonstrated much more bone loss than did obese women, this difference being most striking among smokers.

Evaluation of an injectable hydrogel and polymethyl methacrylate in restoring mechanics to compressively fractured spine motion segments.

PubMed

Balkovec, Christian; Vernengo, Andrea J; Stevenson, Peter; McGill, Stuart M

2016-11-01

Compressive fracture can produce profound changes to the mechanical profile of a spine segment. Minimally invasive repair has the potential to restore both function and structural integrity to an injured spine. Use of both hydrogels to address changes to the disc, combined with polymethyl methacrylate (PMMA) to address changes to the vertebral body, has the potential to facilitate repair. The purpose of this investigation was to determine if the combined use of hydrogel injection and PMMA could restore the mechanical profile of an axially injured spinal motion segment. This is a basic science study evaluating a combination of hydrogel injection and vertebroplasty on restoring mechanics to compressively injured porcine spine motion segments. Fourteen porcine spine motion segments were subject to axial compression until fracture using a dynamic servohydraulic testing apparatus. Rotational and compressive stiffness was measured for each specimen under the following conditions: initial undamaged, fractured, fatigue loading under compression, hydrogel injection, PMMA injection, and fatigue loading under compression. Group 1 received hydrogel injection followed by PMMA injection, whereas Group 2 received PMMA injection followed by hydrogel injection. This study was funded under a Natural Sciences and Engineering Research Council of Canada discovery grant. PMMA injection was found to alter the compressive stiffness properties of axially injured spine motion segments, restoring values from Groups 1 and 2 to 89.3%±29.3% and 81%±27.9% of initial values respectively. Hydrogel injection was found to alter the rotational stiffness properties, restoring specimens in Groups 1 and 2 to 151.5%±81% and 177.2%±54.9% of initial values respectively. Prolonged restoration of function was not possible, however, after further fatigue loading. Using this repair technique, replication of the mechanism of injury appears to cause a rapid deterioration in function of the motion segments. Containment of the hydrogel appears to be an issue with large breaches in the end plate, as it is posited to migrate into the cancellous bone of the vertebral body. Future work should attempt to evaluate methods in fully sealing the disc space. Copyright © 2016 Elsevier Inc. All rights reserved.

Vertebral body bone strength: the contribution of individual trabecular element morphology.

PubMed

Parkinson, I H; Badiei, A; Stauber, M; Codrington, J; Müller, R; Fazzalari, N L

2012-07-01

Although the amount of bone explains the largest amount of variability in bone strength, there is still a significant proportion unaccounted for. The morphology of individual bone trabeculae explains a further proportion of the variability in bone strength and bone elements that contribute to bone strength depending on the direction of loading. Micro-CT imaging enables measurement of bone microarchitecture and subsequently mechanical strength of the same sample. It is possible using micro-CT data to perform morphometric analysis on individual rod and plate bone trabeculae using a volumetric spatial decomposition algorithm and hence determine their contribution to bone strength. Twelve pairs of vertebral bodies (T12/L1 or L4/L5) were harvested from human cadavers, and bone cubes (10 × 10 × 10 mm) were obtained. After micro-CT imaging, a volumetric spatial decomposition algorithm was applied, and measures of individual trabecular elements were obtained. Bone strength was measured in compression, where one bone specimen from each vertebral segment was tested supero-inferiorly (SI) and the paired specimen was tested antero-posteriorly (AP). Bone volume fraction was the strongest individual determinant of SI strength (r(2) = 0.77, p < 0.0001) and AP (r(2) = 0.54, p < 0.0001). The determination of SI strength was improved to r(2) = 0.87 with the addition of mean rod length and relative plate bone volume fraction. The determination of AP strength was improved to r(2) = 0.85 with the addition of mean rod volume and relative rod bone volume fraction. Microarchitectural measures of individual trabeculae that contribute to bone strength have been identified. In addition to the contribution of BV/TV, trabecular rod morphology increased the determination of AP strength by 57%, whereas measures of trabecular plate and rod morphology increased determination of SI strength by 13%. Decomposing vertebral body bone architecture into its constituent morphological elements shows that trabecular element morphology has specific functional roles to assist in maintaining skeletal integrity.

Carcasses of invasive species are predominantly utilized by invasive scavengers in an island ecosystem

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

Abernethy, Erin F.; Turner, Kelsey L.; Beasley, James C.

Invasive species have significantly affected ecosystems, particularly islands, and species invasions continue with increasing globalization. Largely unstudied, the influence of invasive species on island ecosystem functions, especially scavenging and decomposition, could be substantive. Quantifying carcass utilization by different scavengers and shifts in community dynamics in the presence of invasive animals is of particular interest for understanding impacts on nutrient recycling. Invasive species could benefit greatly from carcass resources within highly invaded island ecosystems, through increased invasion success and population growth, subsequently exacerbating their impacts on native species. Here, we quantified how experimentally placed invasive amphibian, reptile, small mammal, and birdmore » carcasses were utilized by vertebrate and invertebrate scavengers on the Big Island of Hawai’i in three island habitats: a barren lava field, a vegetated lava field, and a rainforest. We used camera traps to record vertebrate scavengers removing carcasses and elapsed time until removal. We evaluated differences in cavenging between vertebrates and invertebrates and within the vertebrate community across different habitats and carcass types. Despite the small carcass sizes (<1 kg) used in this study, 55% of carcasses were removed by vertebrate scavengers, all invasive: mongoose, rodents, cats, pigs, and a common myna. Our data indicate that invasive vertebrate scavengers in this island ecosystem are highly efficient at assimilating a range of carrion resources across a variety of habitats. Carcasses of invasive animals could contribute substantially to energy budgets of other invasive vertebrate species. Finally, this may be a critical component contributing to successful invasions especially on islands and subsequent impacts on ecosystem function.« less

Carcasses of invasive species are predominantly utilized by invasive scavengers in an island ecosystem

DOE PAGES

Abernethy, Erin F.; Turner, Kelsey L.; Beasley, James C.; ...

2016-10-01

Invasive species have significantly affected ecosystems, particularly islands, and species invasions continue with increasing globalization. Largely unstudied, the influence of invasive species on island ecosystem functions, especially scavenging and decomposition, could be substantive. Quantifying carcass utilization by different scavengers and shifts in community dynamics in the presence of invasive animals is of particular interest for understanding impacts on nutrient recycling. Invasive species could benefit greatly from carcass resources within highly invaded island ecosystems, through increased invasion success and population growth, subsequently exacerbating their impacts on native species. Here, we quantified how experimentally placed invasive amphibian, reptile, small mammal, and birdmore » carcasses were utilized by vertebrate and invertebrate scavengers on the Big Island of Hawai’i in three island habitats: a barren lava field, a vegetated lava field, and a rainforest. We used camera traps to record vertebrate scavengers removing carcasses and elapsed time until removal. We evaluated differences in cavenging between vertebrates and invertebrates and within the vertebrate community across different habitats and carcass types. Despite the small carcass sizes (<1 kg) used in this study, 55% of carcasses were removed by vertebrate scavengers, all invasive: mongoose, rodents, cats, pigs, and a common myna. Our data indicate that invasive vertebrate scavengers in this island ecosystem are highly efficient at assimilating a range of carrion resources across a variety of habitats. Carcasses of invasive animals could contribute substantially to energy budgets of other invasive vertebrate species. Finally, this may be a critical component contributing to successful invasions especially on islands and subsequent impacts on ecosystem function.« less

Vertebroplasty versus sham procedure for painful acute osteoporotic vertebral compression fractures (VERTOS IV): randomised sham controlled clinical trial.

PubMed

Firanescu, Cristina E; de Vries, Jolanda; Lodder, Paul; Venmans, Alexander; Schoemaker, Marinus C; Smeet, Albert J; Donga, Esther; Juttmann, Job R; Klazen, Caroline A H; Elgersma, Otto E H; Jansen, Frits H; Tielbeek, Alexander V; Boukrab, Issam; Schonenberg, Karen; van Rooij, Willem Jan J; Hirsch, Joshua A; Lohle, Paul N M

2018-05-09

To assess whether percutaneous vertebroplasty results in more pain relief than a sham procedure in patients with acute osteoporotic compression fractures of the vertebral body. Randomised, double blind, sham controlled clinical trial. Four community hospitals in the Netherlands, 2011-15. 180 participants requiring treatment for acute osteoporotic vertebral compression fractures were randomised to either vertebroplasty (n=91) or a sham procedure (n=89). Participants received local subcutaneous lidocaine (lignocaine) and bupivacaine at each pedicle. The vertebroplasty group also received cementation, which was simulated in the sham procedure group. Main outcome measure was mean reduction in visual analogue scale (VAS) scores at one day, one week, and one, three, six, and 12 months. Clinically significant pain relief was defined as a decrease of 1.5 points in VAS scores from baseline. Secondary outcome measures were the differences between groups for changes in the quality of life for osteoporosis and Roland-Morris disability questionnaire scores during 12 months' follow-up. The mean reduction in VAS score was statistically significant in the vertebroplasty and sham procedure groups at all follow-up points after the procedure compared with baseline. The mean difference in VAS scores between groups was 0.20 (95% confidence interval -0.53 to 0.94) at baseline, -0.43 (-1.17 to 0.31) at one day, -0.11 (-0.85 to 0.63) at one week, 0.41 (-0.33 to 1.15) at one month, 0.21 (-0.54 to 0.96) at three months, 0.39 (-0.37 to 1.15) at six months, and 0.45 (-0.37 to 1.24) at 12 months. These changes in VAS scores did not, however, differ statistically significantly between the groups during 12 months' follow-up. The results for secondary outcomes were not statistically significant. Use of analgesics (non-opioids, weak opioids, strong opioids) decreased statistically significantly in both groups at all time points, with no statistically significant differences between groups. Two adverse events occurred in the vertebroplasty group: one respiratory insufficiency and one vasovagal reaction. Percutaneous vertebroplasty did not result in statistically significantly greater pain relief than a sham procedure during 12 months' follow-up among patients with acute osteoporotic vertebral compression fractures. ClinicalTrials.gov NCT01200277. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Digital data registration and differencing compression system

NASA Technical Reports Server (NTRS)

Ransford, Gary A. (Inventor); Cambridge, Vivien J. (Inventor)

1990-01-01

A process is disclosed for x ray registration and differencing which results in more efficient compression. Differencing of registered modeled subject image with a modeled reference image forms a differenced image for compression with conventional compression algorithms. Obtention of a modeled reference image includes modeling a relatively unrelated standard reference image upon a three-dimensional model, which three-dimensional model is also used to model the subject image for obtaining the modeled subject image. The registration process of the modeled subject image and modeled reference image translationally correlates such modeled images for resulting correlation thereof in spatial and spectral dimensions. Prior to compression, a portion of the image falling outside a designated area of interest may be eliminated, for subsequent replenishment with a standard reference image. The compressed differenced image may be subsequently transmitted and/or stored, for subsequent decompression and addition to a standard reference image so as to form a reconstituted or approximated subject image at either a remote location and/or at a later moment in time. Overall effective compression ratios of 100:1 are possible for thoracic x ray digital images.

Digital Data Registration and Differencing Compression System

NASA Technical Reports Server (NTRS)

Ransford, Gary A. (Inventor); Cambridge, Vivien J. (Inventor)

1996-01-01

A process for X-ray registration and differencing results in more efficient compression. Differencing of registered modeled subject image with a modeled reference image forms a differenced image for compression with conventional compression algorithms. Obtention of a modeled reference image includes modeling a relatively unrelated standard reference image upon a three-dimensional model, which three-dimensional model is also used to model the subject image for obtaining the modeled subject image. The registration process of the modeled subject image and modeled reference image translationally correlates such modeled images for resulting correlation thereof in spatial and spectral dimensions. Prior to compression, a portion of the image falling outside a designated area of interest may be eliminated, for subsequent replenishment with a standard reference image. The compressed differenced image may be subsequently transmitted and/or stored, for subsequent decompression and addition to a standard reference image so as to form a reconstituted or approximated subject image at either a remote location and/or at a later moment in time. Overall effective compression ratios of 100:1 are possible for thoracic X-ray digital images.

Digital data registration and differencing compression system

NASA Technical Reports Server (NTRS)

Ransford, Gary A. (Inventor); Cambridge, Vivien J. (Inventor)

1992-01-01

A process for x ray registration and differencing results in more efficient compression is discussed. Differencing of registered modeled subject image with a modeled reference image forms a differential image for compression with conventional compression algorithms. Obtention of a modeled reference image includes modeling a relatively unrelated standard reference image upon a three dimensional model, which three dimensional model is also used to model the subject image for obtaining the modeled subject image. The registration process of the modeled subject image and modeled reference image translationally correlates such modeled images for resulting correlation thereof in spatial and spectral dimensions. Prior to compression, a portion of the image falling outside a designated area of interest may be eliminated, for subsequent replenishment with a standard reference image. The compressed differenced image may be subsequently transmitted and/or stored, for subsequent decompression and addition to a standard reference image so as to form a reconstituted or approximated subject image at either remote location and/or at a later moment in time. Overall effective compression ratios of 100:1 are possible for thoracic x ray digital images.

Vertebral Uptake of Tc-99m Macroaggregated Albumin (MAA) with SPECT/CT Occurring in Superior Vena Cava Obstruction.

PubMed

Karls, Shawn; Hassoun, Hani; Derbekyan, Vilma

2016-09-01

A 67-year-old male presented with dyspnea for which lung scintigraphy was ordered to rule out pulmonary embolus. Planar images demonstrated abnormal midline uptake of Tc-99m macroaggregated albumin, which SPECT/CT localized to several thoracic vertebrae. Thoracic vertebral uptake on perfusion lung scintigraphy was previously described on planar imaging. Radionuclide venography and contrast-enhanced CT subsequently demonstrated superior vena cava (SVC) obstruction with collateralization through the azygous/hemiazygous system and vertebral venous plexus. SPECT/CT differentiated residual esophageal/tracheal ventilation activity, a clinically insignificant finding, from vertebral uptake indicative of SVC obstruction, a potentially life-threatening condition.

A Mass Tracking Formulation for Bubbles in Incompressible Flow

DTIC Science & Technology

2012-10-14

incompressible flow to fully nonlinear compressible flow including the effects of shocks and rarefactions , and then subsequently making a number of...using the ideas from [19] to couple together incompressible flow with fully nonlinear compressible flow including shocks and rarefactions . The results...compressible flow including the effects of shocks and rarefactions , and then subsequently making a number of simplifying assumptions on the air flow

Chordoma of the thoracic vertebrae in a Bengal tiger (Panthera tigris tigris)

PubMed Central

KURAMOCHI, Mizuki; IZAWA, Takeshi; HORI, Mayuka; KUSUDA, Kayo; SHIMIZU, Junichiro; ISERI, Toshie; AKIYOSHI, Hideo; OHASHI, Fumihito; KUWAMURA, Mitsuru; YAMATE, Jyoji

2015-01-01

A 19-year-old female Bengal tiger (Panthera tigris tigris) was presented with hind limb weakness, ataxia and respiratory distress. Computed tomography revealed a mass between the left side of the T7 vertebra and the base of the left 7th rib. The tiger then died, and necropsy was performed. Grossly, the vertebral mass was 6 × 5.7 × 3 cm, and invaded the adjacent vertebral bone and compressed the T7 spinal cord. Histologically, the mass was composed of large, clear, vacuolated and polygonal cells with osteochondral matrix. Cellular and nuclear atypia were moderate. The vacuolated cells stained positively for cytokeratin and vimentin and negatively for S-100. Based on these findings, the present case was diagnosed as a vertebral chordoma; the first report in a tiger. PMID:25766770

AORTIC INJURY DUE TO PARAGLIDING: A CASE REPORT

PubMed Central

Omori, Kazuhiko; Jitsuiki, Kei; Majima, Takashi; Takeuchi, Ikuto; Yoshizaw, Toshihiko; Ishikawa, Kouhei; Ohsaka, Hiromichi; Tambara, Keiichi

2017-01-01

A 64-year-old male fell from an altitude of 10 m while paragliding after stalling due to the wind. The purpose of this case report is to describe the outcomes after multiple injuries sustained during a paragliding accident, including a potentially life-threating injury to the thoracic aorta. The subject sustained a bite wound on his tongue, injuries to his chest (left side) and back, and a right forearm deformity. Enhanced whole body computed tomography (CT) revealed fractures of the bilateral laminae of the second and third cervical bones, right first rib, the tenth thoracic vertebral body (compression type), second lumbar vertebral body (burst type) and the right radius, Other injuries included an injury to the thoracic aortic arch and the presence of intraabdominal fluid collection without perforation of the digestive tract. Endovascular treatment was selected for the aortic injury because of multiple injuries. Immediate management included hypotensive rate control therapy using calcium and a beta blocker. On the fourth hospital day, the subject underwent deployment of a stent-graft to the aorta and subsequent surgical immobilization for the lumbar burst fracture. He also underwent surgical immobilization of the radial fracture and was discharged on the 28th hospital day. First responders or physicians should consider the possibility of aortic injury when treating patients who suffer falls while paragliding and provide appropriate management. Failure to provide appropriate management of an aortic injury could result in death. Level of Evidence 4 PMID:28593092

Effective treatment of severe pregnancy and lactation-related osteoporosis with teriparatide: case report and review of the literature.

PubMed

Polat, Sefika Burcak; Evranos, Berna; Aydin, Cevdet; Cuhaci, Neslihan; Ersoy, Reyhan; Cakir, Bekir

2015-07-01

Pregnancy or lactation-related osteoporosis (PLO) is a very rare and debilitating condition which is usually diagnosed during the last trimester of the pregnancy or early postpartum period. Herein, we report a case with severe PLO and multiple vertebral compression fractures that were successfully treated with teriparatide. Twenty-three-year-old female patient was admitted to our clinic two months after her first spontaneous vaginal delivery with the complaint of severe back pain. Bone mineral density was measured using dual energy X-ray absorptiometry (DEXA), and low T- and Z-scores were observed in lumbar vertebrae. In vertebral MRI, severe height loss was detected in thoracic (T) 5,7,10,11,12 vertebrae. After exclusion of the other possible causes of OP, she was diagnosed to have PLO and the lactation was stopped. She was treated with calcium 1000 mg/day, cholecalciferol 800 mg/day and teriparatide 20 µg/day. At the 12th and 18th month of therapy, BMD was increased by 8% and 27%, respectively, at the lumbar spine and pain was completely relieved in few months. There are pharmacological therapy modalities that can be used in PLO. Bisphosphonates are effective, but there are some concerns that they accumulate in bone and may expose fetus in subsequent pregnancies. Teriparatide is a strong candidate to be the optimal medical therapy in severe cases since it is effective and safe.

Which is best for osteoporotic vertebral compression fractures: balloon kyphoplasty, percutaneous vertebroplasty or non-surgical treatment? A study protocol for a Bayesian network meta-analysis

PubMed Central

Kan, Shun-Li; Yuan, Zhi-Fang; Chen, Ling-Xiao; Sun, Jing-Cheng; Ning, Guang-Zhi; Feng, Shi-Qing

2017-01-01

Introduction Osteoporotic vertebral compression fractures (OVCFs) commonly cause both acute and chronic back pain, substantial spinal deformity, functional disability and decreased quality of life and increase the risk of future vertebral fractures and mortality. Percutaneous vertebroplasty (PVP), balloon kyphoplasty (BK) and non-surgical treatment (NST) are mostly used for the treatment of OVCFs. However, which treatment is preferred is unknown. The purpose of this study is to comprehensively review the literature and ascertain the relative efficacy and safety of BK, PVP and NST for patients with OVCFs using a Bayesian network meta-analysis. Methods and analysis We will comprehensively search PubMed, EMBASE and the Cochrane Central Register of Controlled Trials, to include randomided controlled trials that compare BK, PVP or NST for treating OVCFs. The risk of bias for individual studies will be assessed according to the Cochrane Handbook. Bayesian network meta-analysis will be performed to compare the efficacy and safety of BK, PVP and NST. The quality of evidence will be evaluated by GRADE. Ethics and dissemination Ethical approval and patient consent are not required since this study is a meta-analysis based on published studies. The results of this network meta-analysis will be submitted to a peer-reviewed journal for publication. PROSPERO registration number CRD42016039452; Pre-results. PMID:28093431

MRI Evaluation of Spinal Length and Vertebral Body Angle During Loading with a Spinal Compression Harness

NASA Technical Reports Server (NTRS)

Campbell, James A.; Hargens, Alan R.; Murthy, G.; Ballard, R. E.; Watenpaugh, D. E.; Hargens, Alan, R.; Sanchez, E.; Yang, C.; Mitsui, I.; Schwandt, D.;

Bacterial diskospondylitis in juvenile mink from 2 Ontario mink farms

PubMed Central

Martínez, Jorge; Vidaña, Beatriz; Cruz-Arambulo, Robert; Slavic, Durda; Tapscott, Brian; Brash, Marina L.

2013-01-01

Nine juvenile mink with hind-limb paresis/paralysis from 2 Ontario farms were submitted for necropsy. Diagnostic tests revealed spinal compression and severe thoracic diskospondylitis with intralesional Gram-positive coccoid bacterial colonies. Streptococcus canis, Streptococcus dysgalactiae subsp. equisimilis, and hemolytic Staphylococcus spp. were isolated from vertebral lesions. PMID:24155490

Bacterial diskospondylitis in juvenile mink from 2 Ontario mink farms.

PubMed

Martínez, Jorge; Vidaña, Beatriz; Cruz-Arambulo, Robert; Slavic, Durda; Tapscott, Brian; Brash, Marina L

2013-09-01

Nine juvenile mink with hind-limb paresis/paralysis from 2 Ontario farms were submitted for necropsy. Diagnostic tests revealed spinal compression and severe thoracic diskospondylitis with intralesional Gram-positive coccoid bacterial colonies. Streptococcus canis, Streptococcus dysgalactiae subsp. equisimilis, and hemolytic Staphylococcus spp. were isolated from vertebral lesions.

Case studies of spinal deformities in ornamental koi, Cyprinus carpio L.

PubMed

Chin, H N; Loh, R; Hong, Y C; Gibson-Kueh, S

2017-01-01

This is a study of vertebral deformities in ornamental koi based on computed radiography and skeletons cleaned by dermestid beetles (Dermestes maculatus). All koi developed gradual onset of swimming abnormalities as adults. Extensive intervertebral osteophyte formation correlated with age of fish and was associated with hindquarter paresis in one koi. Vertebral compression and fusion were the most common spinal deformities occurring at multiple sites, similar to findings in other farmed fish. Site-specific spinal deformities were thought to develop due to differences in swimming behaviour and rates of vertebral growth. One koi had offspring with spinal deformities. Spinal deformities are significant problems in both European and Australian food fish hatcheries. The heritability of vertebral deformities in farmed fish is reportedly low unless there is concurrent poor husbandry or nutritional deficiencies. The specific aetiologies for vertebral deformities in koi in this study could not be ascertained. Current knowledge on spinal deformities in the better studied European food fish species suggests multifactorial aetiologies. Future research should include prospective longitudinal studies of larger numbers of koi from hatch and consideration of all potential risk factors such as husbandry, nutrition, temperature, photoperiod and genetics. © 2016 John Wiley & Sons Ltd.

A proposed radiographic classification scheme for congenital thoracic vertebral malformations in brachycephalic "screw-tailed" dog breeds.

PubMed

Gutierrez-Quintana, Rodrigo; Guevar, Julien; Stalin, Catherine; Faller, Kiterie; Yeamans, Carmen; Penderis, Jacques

2014-01-01

Congenital vertebral malformations are common in brachycephalic "screw-tailed" dog breeds such as French bulldogs, English bulldogs, Boston terriers, and pugs. The aim of this retrospective study was to determine whether a radiographic classification scheme developed for use in humans would be feasible for use in these dog breeds. Inclusion criteria were hospital admission between September 2009 and April 2013, neurologic examination findings available, diagnostic quality lateral and ventro-dorsal digital radiographs of the thoracic vertebral column, and at least one congenital vertebral malformation. Radiographs were retrieved and interpreted by two observers who were unaware of neurologic status. Vertebral malformations were classified based on a classification scheme modified from a previous human study and a consensus of both observers. Twenty-eight dogs met inclusion criteria (12 with neurologic deficits, 16 with no neurologic deficits). Congenital vertebral malformations affected 85/362 (23.5%) of thoracic vertebrae. Vertebral body formation defects were the most common (butterfly vertebrae 6.6%, ventral wedge-shaped vertebrae 5.5%, dorsal hemivertebrae 0.8%, and dorso-lateral hemivertebrae 0.5%). No lateral hemivertebrae or lateral wedge-shaped vertebrae were identified. The T7 vertebra was the most commonly affected (11/28 dogs), followed by T8 (8/28 dogs) and T12 (8/28 dogs). The number and type of vertebral malformations differed between groups (P = 0.01). Based on MRI, dorsal, and dorso-lateral hemivertebrae were the cause of spinal cord compression in 5/12 (41.6%) of dogs with neurologic deficits. Findings indicated that a modified human radiographic classification system of vertebral malformations is feasible for use in future studies of brachycephalic "screw-tailed" dogs. © 2014 American College of Veterinary Radiology.

Destructive discovertebral degenerative disease of the lumbar spine.

PubMed

Charran, A K; Tony, G; Lalam, R; Tyrrell, P N M; Tins, B; Singh, J; Eisenstein, S M; Balain, B; Trivedi, J M; Cassar-Pullicino, V N

2012-09-01

The uncommon variant of degenerative hip joint disease, termed rapidly progressive osteoarthritis, and highlighted by severe joint space loss and osteochondral disintegration, is well established. We present a similar unusual subset in the lumbar spine termed destructive discovertebral degenerative disease (DDDD) with radiological features of vertebral malalignment, severe disc resorption, and "bone sand" formation secondary to vertebral fragmentation. Co-existing metabolic bone disease is likely to promote the development of DDDD of the lumbar spine, which presents with back pain and sciatica due to nerve root compression by the "bone sand" in the epidural space. MRI and CT play a complimentary role in making the diagnosis.

Development and Validation of a Musculoskeletal Model of the Fully Articulated Thoracolumbar Spine and Rib Cage

PubMed Central

Bruno, Alexander G.; Bouxsein, Mary L.; Anderson, Dennis E.

2015-01-01

We developed and validated a fully articulated model of the thoracolumbar spine in opensim that includes the individual vertebrae, ribs, and sternum. To ensure trunk muscles in the model accurately represent muscles in vivo, we used a novel approach to adjust muscle cross-sectional area (CSA) and position using computed tomography (CT) scans of the trunk sampled from a community-based cohort. Model predictions of vertebral compressive loading and trunk muscle tension were highly correlated to previous in vivo measures of intradiscal pressure (IDP), vertebral loading from telemeterized implants and trunk muscle myoelectric activity recorded by electromyography (EMG). PMID:25901907

Two-Stage Surgical Management of Multilevel Symptomatic Thoracic Haemangioma Using Ethanol and Iliac Crest Bone Graft

PubMed Central

Brahmajoshyula, Venkatramana; Mayi, Shivanand; Teegala, Suman

2014-01-01

This article presents a 56-year-old obese female who presented with back pain and progressive weakness in her lower limbs for three months. She was bed-ridden for one week before reporting to our hospital. Plain radiographs showed vertical striations in multiple vertebrae classical of haemangioma. Magnetic resonance imaging (MRI) spine revealed multiple thoracic and lumbar vertebral haemangiomas. Extra osseous extension of haemangioma at T12 was causing spinal cord compression. Two-stage surgery was performed with absolute alcohol (ethanol) injection followed by pedicle screw fixation and decompression with tricortical iliac crest bone graft into the vertebral body. Postoperatively rapid neurological improvement was seen. After three weeks, she could walk independently. One year later, computed tomography showed complete incorporation of bone graft and maintained vertebral body height. MRI showed complete resolution of the cord edema at T12. These findings indicated diminished vascularity of the tumor. PMID:25187869

[Low back pain vs. leg dominant pain].

PubMed

Kovac, Ida

2011-01-01

There are two patterns of back pain: 1) back-dominant pain and 2) leg pain dominant, greater than back pain. The causes of back pain are very different and numerous, but mostly are due to vertebral, mechanical etiology, and rarely because of non vertebral, visceral etiology. Leg pain greater than back pain is mostly disease of spinal nerve root, generally presented by radicular pain in a dermatomal distribution. Mechanical compression of spinal roots, caused by disc herniation or by spinal stenosis, results in radicular symptoms. Rarely, in about 1% of patients, there are some other reasons except vertebral mechanical cause, like infection, tumor or fracture. There are several causes of pseudoradicular pain like periferal neuropathy, myifascial syndromes, vascular diseases, osteoarthritis. Spondylarthropathies should be taken in cosideration as well. A complete history and physical examination is important to determine further diagnostic evaluation and to provide eficient therapy.

Arterial relationships to the nerves and some rigid structures in the posterior cranial fossa.

PubMed

Surchev, N

2008-09-01

The close relationships between the cranial nerves and the arterial vessels in the posterior cranial fossa are one of the predisposing factors for artery-nerve compression. The aim of this study was to examine the relationships of the vertebral and basilar arteries to some skull and dural structures and the nerves in the posterior cranial fossa. For this purpose, the skull bases and brains of 70 cadavers were studied. The topographic relationships of the vertebral and basilar arteries to the cranial nerves in the posterior cranial fossa were studied and the distances between the arteries and some osseous formations were measured. The most significant variations in arterial position were registered in the lower half of the basilar artery. Direct contact with an artery was established for the hypoglossal canal, jugular tubercle, and jugular foramen. The results reveal additional information about the relationships of the nerves and arteries to the skull and dural formations in the posterior cranial fossa. New quantitative information is given to illustrate them. The conditions for possible artery-nerve compression due to arterial dislocation are discussed and two groups (lines) of compression points are suggested. The medial line comprises of the brain stem points, usually the nerve root entry/exit zone. The lateral line includes the skull eminences, on which the nerves lie, or skull and dural foramina through which they exit the cranial cavity. (c) 2008 Wiley-Liss, Inc.

Metastatic anal sac adenocarcinoma in a dog presenting for acute paralysis

PubMed Central

2004-01-01

Abstract A 4-year old, female spayed terrier was referred for hind end paresis that rapidly progressed to paralysis. Spinal radiographs revealed vertebral collapse and bony lysis. Myelography confirmed spinal cord compression and surgical exploration found an extradural soft tissue mass. Metastatic anal sac adenocarcinoma was diagnosed at postmortem examination. PMID:15368742

Metastatic anal sac adenocarcinoma in a dog presenting for acute paralysis.

PubMed

Brisson, Brigitte A; Whiteside, Douglas P; Holmberg, David L

2004-08-01

A 4-year old, female spayed terrier was referred for hind end paresis that rapidly progressed to paralysis. Spinal radiographs revealed vertebral collapse and bony lysis. Myelography confirmed spinal cord compression and surgical exploration found an extradural soft tissue mass. Metastatic anal sac adenocarcinoma was diagnosed at postmortem examination.

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

McGraw, J. Kevin; Strnad, Bradley T.; Patzik, Shayle B.

Percutaneous vertebroplasty with polymethylmethacrylate (PMMA) is an effective procedure for relieving pain due to vertebral body compression fractures. The technique employs iodinated contrast venography to exclude needle placement directly within the basivertebral complex. We present two cases in which carbon dioxide (CO{sub 2}) and gadopentetate dimeglumine venography was used to guide percutaneous vertebroplasty in patients with a contraindication to iodinated contrast.

Spinal osteosarcoma in a hedgehog with pedal self-mutilation.

PubMed

Rhody, Jeffrey L; Schiller, Chris A

2006-09-01

An African pygmy hedgehog (Atelerix albiventris) was diagnosed with osteosarcoma of vertebral origin with compression of the spinal cord and spinal nerves. The only presenting sign was a self-mutilation of rear feet. Additional diagnoses included a well-differentiated splenic hemangiosarcoma, an undifferentiated sarcoma of the ascending colon, and membranoproliferative glomerulonephritis.

Cement pulmonary embolism after vertebroplasty.

PubMed

Sifuentes Giraldo, Walter Alberto; Lamúa Riazuelo, José Ramón; Gallego Rivera, José Ignacio; Vázquez Díaz, Mónica

2013-01-01

In recent years, the use of vertebral cementing techniques for vertebroplasty and kyphoplasty has spread for the treatment of pain associated with osteoporotic vertebral compression fractures. This is also associated with the increased incidence of complications related with these procedures, the most frequent being originated by leakage of cementation material. Cement can escape into the vertebral venous system and reach the pulmonary circulation through the azygous system and cava vein, producing a cement embolism. This is a frequent complication, occurring in up to 26% of patients undergoing vertebroplasty but, since most patients have no clinical or hemodynamical repercussion, this event usually goes unnoticed. However, some serious, and even fatal cases, have been reported. We report the case of a 74-year-old male patient who underwent vertebroplasty for persistent pain associated with osteoporotic L3 vertebral fracture and who developed a cement leak into the cava vein and right pulmonary artery during the procedure. Although he developed a pulmonary cement embolism, the patient remained asymptomatic and did not present complications during follow-up. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Total En Bloc Spondylectomy for Locally Aggressive Vertebral Hemangioma Causing Neurological Deficits

PubMed Central

Ogawa, Ryo; Hikata, Tomohiro; Fujita, Nobuyuki; Iwanami, Akio; Watanabe, Kota; Ishii, Ken; Nakamura, Masaya; Toyama, Yoshiaki; Matsumoto, Morio

2015-01-01

Vertebral hemangiomas are common; however, aggressive vertebral hemangiomas with extraosseous extensions causing neurological deficits are rare. The treatment for this subtype of hemangioma remains controversial, since there are few reports on long-term clinical outcomes or tumor recurrence rates. We describe a case of aggressive vertebral hemangioma treated by total en bloc spondylectomy, with a literature review focusing on long-term recurrence. A 52-year-old male with a two-month history of numbness in the bilateral lower extremities was referred to our hospital. Imaging studies showed a tumor originating in the T9 vertebra and extending to the T8 and T10 vertebrae, with extraosseous extension causing spinal-cord compression. Ten months after onset, the patient presented with progressive paraparesis and hypalgesia. Total en bloc spondylectomy was performed, and pathology was consistent with cavernous hemangioma. Motor and sensory deficits improved significantly, and no signs of recurrence are seen at 2.5 years after operation. A review of literature revealed a recurrence rate of 12.7% (10/79 cases). The available evidence indicates satisfactory long-term outcomes for total tumor resection without adjuvant radiotherapy. PMID:25918662

Data compression of discrete sequence: A tree based approach using dynamic programming

NASA Technical Reports Server (NTRS)

Shivaram, Gurusrasad; Seetharaman, Guna; Rao, T. R. N.

1994-01-01

A dynamic programming based approach for data compression of a ID sequence is presented. The compression of an input sequence of size N to that of a smaller size k is achieved by dividing the input sequence into k subsequences and replacing the subsequences by their respective average values. The partitioning of the input sequence is carried with the intention of reducing the mean squared error in the reconstructed sequence. The complexity involved in finding the partitions which would result in such an optimal compressed sequence is reduced by using the dynamic programming approach, which is presented.

Aspergillus terreus infection of pseudoaneurysm of aortofemoral vascular graft with contiguous vertebral osteomyelitis.

PubMed

Glotzbach, R E

1982-02-01

This is a case report of a patient who developed several unusual complications of an aortofemoral vascular graft. These were thrombosis, pseudoaneurysm, and infection. There was an Aspergillus terreus infection of the pseudoaneurysm of the vascular prosthesis. A contiguous vertebral osteomyelitis due to A. terreus subsequently developed. This represented a localized, invasive form of aspergillosis.

Height restoration and maintenance after treating unstable osteoporotic vertebral compression fractures by cement augmentation is dependent on the cement volume used.

PubMed

Krüger, Antonio; Baroud, Gamal; Noriega, David; Figiel, Jens; Dorschel, Christine; Ruchholtz, Steffen; Oberkircher, Ludwig

2013-08-01

Two different procedures, used for percutaneous augmentation of vertebral compression fractures were compared, with respect to height restoration and maintenance after cyclic loading. Additionally the impact of the cement volume used was investigated. Wedge compression fractures were created in 36 human cadavaric vertebrae (T10-L3). Twenty-seven vertebrae were treated with the SpineJack® with different cement volumes (maximum, intermediate, and no cement), and 9 vertebrae were treated with Balloon Kyphoplasty. Vertebral heights were measured pre- and postfracture as well as after treatment and loading. Cyclic loading was performed with 10,000cycles (1Hz, 100-600N). The average anterior height after restoration was 85.56% for Kyphoplasty; 96.20% for SpineJack® no cement; 93.44% for SpineJack® maximum and 96% for the SpineJack® intermediate group. The average central height after restoration was 93.89% for Kyphoplasty; 100.20% for SpineJack® no cement; 99.56% for SpineJack® maximum and 101.13% for the SpineJack® intermediate group. The average anterior height after cyclic loading was 85.33 % for Kyphoplasty; 87.30% in the SpineJack® no cement, 92% in the SpineJack® maximum and 87% in the SpineJack® intermediate group. The average central height after cyclic loading was 92% for Kyphoplasty; 93.80% in the SpineJack® no cement; 98.56% in the SpineJack® maximum and 94.25% in the SpineJack® intermediate group. Height restoration was significantly better for the SpineJack® group compared to Kyphoplasty. Height maintenance was dependent on the cement volume used. The group with the SpineJack® without cement nevertheless showed better results in height maintenance, yet the statistical significance could not be demonstrated. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessment of Mechanical Performance of Bone Architecture Using Rapid Prototyping Models

NASA Astrophysics Data System (ADS)

Saparin, Peter; Woesz, Alexander; Thomsen, Jasper S.; Fratzl, Peter

2008-06-01

The aim of this on-going research project is to assess the influence of bone microarchitecture on the mechanical performance of trabecular bone. A testing chain consist-ing of three steps was established: 1) micro computed tomography (μCT) imaging of human trabecular bone; 2) building of models of the bone from a light-sensitive polymer using Rapid Prototyping (RP); 3) mechanical testing of the models in a material testing machine. A direct resampling procedure was developed to convert μCT data into the format of the RP machine. Standardized parameters for production and testing of the plastic models were established by use of regular cellular structures. Next, normal, osteoporotic, and extreme osteoporotic vertebral trabecular bone architectures were re-produced by RP and compression tested. We found that normal architecture of vertebral trabecular bone exhibit behaviour characteristic of a cellular structure. In normal bone the fracture occurs at much higher strain values that in osteoporotic bone. After the fracture a normal trabecular architecture is able to carry much higher loads than an osteoporotic architecture. However, no statistically significant differences were found in maximal stress during uniaxial compression of the central part of normal, osteoporotic, and extreme osteoporotic vertebral trabecular bone. This supports the hypothesis that osteoporotic trabecular bone can compensate for a loss of trabeculae by thickening the remaining trabeculae in the loading direction (compensatory hypertrophy). The developed approach could be used for mechanical evaluation of structural data acquired non-invasively and assessment of changes in performance of bone architecture.

Percutaneous Vertebroplasty in Multiple Myeloma: Prospective Long-Term Follow-Up in 106 Consecutive Patients

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

Anselmetti, Giovanni Carlo, E-mail: giovanni.anselmetti@ircc.it; Manca, Antonio, E-mail: anto.manca@gmail.com; Montemurro, Filippo, E-mail: filippo.montemurro@ircc.it

Purpose: Percutaneous vertebroplasty (PV) is a minimally invasive procedure involving the injection of bone cement within a collapsed vertebral body. Although this procedure was demonstrated to be effective in osteoporosis and metastases, few studies have been reported in cases of multiple myeloma (MM). We prospectively evaluated the safety and efficacy of PV in the treatment of vertebral compression fractures (VCFs) resulting from MM. Materials and Methods: PV was performed in 106 consecutive MM patients who had back pain due to VCFs, the treatment of which had failed conservative therapies. Follow-up (28.2 {+-} 12.1 months) was evaluated at 7 and 15more » days as well as at 1, 3, 6, 12, 18, and every 6 months after PV. Visual analog scale (VAS) pain score, opioid use, external brace support, and Oswestry Disability Index (ODI) score were recorded. Results: The median pretreatment VAS score of 9 (range 4-10) significantly (P < 0.001) decreased to 1 (range 0-9) after PV. Median pre-ODI values of 82% (range 36-89%) significantly improved to 7% (range 0-82%) (P < 0.001). Differences in pretreatment and posttreatment use of analgesic drug were statistically significant (P < 0.001). The majority of patients (70 of 81; 86%) did not use an external brace after PV (P < 0.001). Conclusion: PV is a safe, effective, and long-lasting procedure for the treatment of vertebral compression pain resulting from MM.« less

[Spinal manipulative therapy and cervical artery dissections].

PubMed

Saxler, G; Schopphoff, E; Quitmann, H; Quint, U

2005-06-01

Severe complications after cervical spine manipulation are rare. As experts for medical treatment errors, we received between July 2002 and February 2004 cases with serious complications in the central nervous system after manipulation. 5 vertebral artery dissections with subsequent brain infarction were registered. In all cases, the patients showed complete persisting remission of symptoms. In addition, a kinematic estimation model was developed to study the possible causes of vertebral artery damage. We were able to demonstrate that material extension is dependent on cervical rotation and the "free length" of the vertebral artery in the upper cervical spine.

Synaptic scaffold evolution generated components of vertebrate cognitive complexity

PubMed Central

Nithianantharajah, J.; Komiyama, N.H.; McKechanie, A.; Johnstone, M.; Blackwood, D. H.; St Clair, D.; Emes, R.D.; van de Lagemaat, L. N.; Saksida, L.M.; Bussey, T.J.; Grant, S.G.N.

2014-01-01

The origins and evolution of higher cognitive functions including complex forms of learning, attention and executive functions are unknown. A potential mechanism driving the evolution of vertebrate cognition early in the vertebrate lineage (550 My ago) was genome duplication and subsequent diversification of postsynaptic genes. Here we report the first genetic analysis of a vertebrate gene family in cognitive functions measured using computerized touchscreens. Comparison of mice carrying mutations in all four Dlg paralogs show simple associative learning required Dlg4, while Dlg2 and Dlg3 diversified to play opposing roles in complex cognitive processes. Exploiting the translational utility of touchscreens in humans and mice, testing Dlg2 mutations in both species showed Dlg2’s role in complex learning, cognitive flexibility and attention has been highly conserved over 100 My. Dlg family mutations underlie psychiatric disorders suggesting genome evolution expanded the complexity of vertebrate cognition at the cost of susceptibility to mental illness. PMID:23201973

Bilateral aortic origins of the vertebral arteries with right vertebral artery arising distal to left subclavian artery: case report.

PubMed

Al-Okaili, Riyadh; Schwartz, Eric D

2007-02-01

Bilateral aortic origins of the vertebral arteries are a rare anatomic variant, with fewer than 20 cases reported in the literature. This particular variant has only been reported twice. A 35-year-old woman presented to the emergency department after trauma to the head and a witnessed convulsion. Subsequent workup included MRI/MRA, which resulted in identification of the anomaly. The clinical importance of aortic arch anomalies lies in that it may be a source of misinterpretation, as one may conclude occlusion of the vertebral artery if the aberrant origin is not included in the MRA or CTA imaging parameters. Therefore, it is important to scan through the entire aortic arch to just below the level of the ligamentum arteriosum when performing these noninvasive modalities. In addition, vertebral arteries arising from the aortic arch have an increased risk of dissection.

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

PubMed

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

2001-05-01

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

Correlative Analysis of Vertebral Trabecular Bone Microarchitecture and Mechanical Properties: A Combined Ultra-high Field (7 Tesla) MRI and Biomechanical Investigation.

PubMed

Guenoun, Daphne; Fouré, Alexandre; Pithioux, Martine; Guis, Sandrine; Le Corroller, Thomas; Mattei, Jean-Pierre; Pauly, Vanessa; Guye, Maxime; Bernard, Monique; Chabrand, Patrick; Champsaur, Pierre; Bendahan, David

2017-10-15

High-resolution imaging and biomechanical investigation of ex-vivo vertebrae. The aim of this study was to assess bone microarchitecture of cadaveric vertebrae using ultra-high field (UHF) 7 Tesla magnetic resonance imaging (MRI) and to determine whether the corresponding microarchitecture parameters were related to bone mineral density (BMD) and bone strength assessed by dual-energy x-ray absorptiometry (DXA) and mechanical compression tests. Limitations of DXA for the assessment of bone fragility and osteoporosis have been recognized and criteria of microarchitecture alteration have been included in the definition of osteoporosis. Although vertebral fracture is the most common osteoporotic fracture, no study has assessed directly vertebral trabecular bone microarchitecture. BMD of 24 vertebrae (L2, L3, L4) from eight cadavers was investigated using DXA. The bone volume fraction (BVF), trabecular thickness (Tb.Th), and trabecular spacing (Tb.Sp) of each vertebra were quantified using UHF MRI. Measurements were performed by two operators to characterize the inter-rater reliability. The whole set of specimens underwent mechanical compression tests to failure and the corresponding failure stress was calculated. The inter-rater reliability for bone microarchitecture parameters was good with intraclass correlation coefficients ranging from 0.82 to 0.94. Failure load and stress were significantly correlated with BVF, Tb.Sp, and BMD (P < 0.05). Tb.Th was only correlated with the failure stress (P < 0.05). Multiple regression analysis demonstrated that the combination of BVF and BMD improved the prediction of the failure stress from an adjusted R = 0.384 for BMD alone to an adjusted R = 0.414. We demonstrated for the first time that the vertebral bone microarchitecture assessed with UHF MRI was significantly correlated with biomechanical parameters. Our data suggest that the multimodal assessment of BMD and trabecular bone microarchitecture with UHF MRI provides additional information on the risk of vertebral bone fracture and might be of interest for the future investigation of selected osteoporotic patients. N /A.

Building the Vertebrate Spine

NASA Astrophysics Data System (ADS)

Pourquié, Olivier

2008-03-01

The vertebrate body can be subdivided along the antero-posterior (AP) axis into repeated structures called segments. This periodic pattern is established during embryogenesis by the somitogenesis process. Somites are generated in a rhythmic fashion from the paraxial mesoderm and subsequently differentiate to give rise to the vertebrae and skeletal muscles of the body. Somite formation involves an oscillator-the segmentation clock-whose periodic signal is converted into the periodic array of somite boundaries. This clock drives the dynamic expression of cyclic genes in the presomitic mesoderm and requires Notch and Wnt signaling. Microarray studies of the mouse presomitic mesoderm transcriptome reveal that the segmentation clock drives the periodic expression of a large network of cyclic genes involved in cell signaling. Mutually exclusive activation of the Notch/FGF and Wnt pathways during each cycle suggests that coordinated regulation of these three pathways underlies the clock oscillator. In humans, mutations in the genes associated to the function of this oscillator such as Dll3 or Lunatic Fringe result in abnormal segmentation of the vertebral column such as those seen in congenital scoliosis. Whereas the segmentation clock is thought to set the pace of vertebrate segmentation, the translation of this pulsation into the reiterated arrangement of segment boundaries along the AP axis involves dynamic gradients of FGF and Wnt signaling. The FGF signaling gradient is established based on an unusual mechanism involving mRNA decay which provides an efficient means to couple the spatio-temporal activation of segmentation to the posterior elongation of the embryo. Another striking aspect of somite production is the strict bilateral symmetry of the process. Retinoic acid was shown to control aspects of this coordination by buffering destabilizing effects from the embryonic left-right machinery. Defects in this embryonic program controlling vertebral symmetry might lead to scoliosis in humans. Finally, the subsequent regional differentiation of the precursors of the vertebrae is controlled by Hox genes, whose collinear expression controls both gastrulation of somite precursors and their subsequent patterning into region-specific types of structures. Therefore somite development provides an outstanding paradigm to study patterning and differentiation in vertebrate embryos.

Zoledronic acid infusion for lumbar interbody fusion in osteoporosis.

PubMed

Tu, Chao-Wei; Huang, Kuo-Feng; Hsu, Hsien-Ta; Li, Hung-Yu; Yang, Stephen Shei-Dei; Chen, Yi-Chu

2014-11-01

Clinical outcomes of intravenous (IV) infusion of zoledronic acid (ZOL) for lumbar interbody fusion surgery (LIFS) remain unknown. We investigated the efficacy of IV ZOL on clinical outcome and bone fusion after LIFS. We retrospectively analyzed 64 patients with both degenerative lumbar spondylolisthesis and osteoporosis who underwent LIFS from January 2007 to April 2010. All patients were followed up for 2 y. Thirty-two were treated with an IV infusion of ZOL 3 d after surgery and a second injection 1 y later, and the other 32 patients did not receive ZOL. Preoperatively and every 3 mo postoperatively, oswestry disability index questionnaire and visual analog scale (VAS) scores for back and leg were compared. Preoperative and final postoperative follow-up to evaluate for subsequent compression fractures were also performed. Pedicle screw loosening, cage subsidence, and fusion rate were documented 2 y after surgery. At 2-y follow-up, a solid fusion was achieved in 75% of the ZOL group and only 56% of the control group. At final follow up, the incidence of final subsequent vertebral compression fractures (19% of the ZOL group and 51% of the control group, P = 0.006), pedicle screw loosening (18% of the ZOL group and 45% of the control group, P = 0.03), and cage subsidence >2 mm (28% of the ZOL group and only 54% of the control group, P = 0.04) were significantly lower in the ZOL group than in the control group. The ZOL group demonstrated improvement in VAS (for leg pain VAS, 2/10 for the ZOL group and 5/10 for the control group; for back pain VAS, 2/10 for the ZOL group and 6/10 for the control group) and oswestry disability index scores (7/25 for the ZOL group and 16/25 for the control group). ZOL treatment has beneficial effects on instrumented LIFS both radiographic and clinically. Thus, ZOL treatment can be recommended for osteoporosis patients undergoing LIFS. Copyright © 2014 Elsevier Inc. All rights reserved.

Rare case of diffuse spinal arachnoiditis following a complicated vertebral artery dissection.

PubMed

Atallah, Elias; Dang, Sophia; Rahm, Sage; Feghali, James; Nohra, Chalouhi; Tjoumakaris, Stavropoula; Rosenwasser, Robert H; Zarzour, Hekmat; Herial, Nabeel; Gooch, Michael Reid; Jabbour, Pascal

2018-06-01

Spinal arachnoiditis (SA) is an extremely rare and delayed complication of subarachnoid hemorrhage (SAH). Little is known about its underlying pathogenesis and subsequent clinical course. A middle-aged patient presented with the worst headache of her life and a grade 3 SAH of the basal-cisterns and posterior fossa was identified on Computed Tomography scans (CT). Angiography revealed a ruptured dissecting aneurysm of the left vertebral artery (VA-V4), as well as an unruptured left Anterior Cerebral Artery (ACA-A1) aneurysm. The VA aneurysm was treated with flow diversion. The patient re-ruptured the stented aneurysm, another telescoping pipeline was placed. The patient developed polymicrobial ventriculitis, and returned several months later complaining of paraparesis and left sided weakness. Magnetic Resonance Imaging (MRI) revealed diffuse thecal dural thickening from the cervicomedullary junction to the sacrum. Loculations, diffuse edema and cord compression were noticed along the inferior surface of the cerebellum, and the cervico-thoracic spine with a T4-T6 syrinx. The patient underwent a posterior (T4-T8) spinal fusion and (T5-T7) decompression with arachnoid-cyst fenestration and placement of a subarachnoid-pleural shunt. On latest follow-up, the patient is weaning off the thoraco-lumbosacral orthosis and ambulating with a cane. SA is often a complicated two-staged disease in which a "free interval phase" separates the initial inflammatory reaction (IIR) from the late adhesive phase. Posterior fossa bleeding, warranting prolonged surveillance, additional bleeding and ventriculitis might augment the risk and the severity of arachnoiditis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Retrieval of Cement Embolus from Inferior Vena Cava After Percutaneous Vertebroplasty

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

Athreya, S., E-mail: sathreya@stjoes.c; Mathias, N.; Rogers, P.

Percutaneous vertebroplasty is an accepted treatment for painful vertebral compression fractures caused by osteoporosis and malignant disease. Venous leakage of cement and pulmonary cement embolism have been reported complications. We describe a paravertebral venous cement leak resulting in the deposition of a cement cast in the inferior vena cava and successful retrieval of the cement embolus.

X-ray diffraction evidence for myosin-troponin connections and tropomyosin movement during stretch activation of insect flight muscle

PubMed Central

Perz-Edwards, Robert J.; Irving, Thomas C.; Baumann, Bruce A. J.; Gore, David; Hutchinson, Daniel C.; Kržič, Uroš; Porter, Rebecca L.; Ward, Andrew B.; Reedy, Michael K.

2011-01-01

Stretch activation is important in the mechanical properties of vertebrate cardiac muscle and essential to the flight muscles of most insects. Despite decades of investigation, the underlying molecular mechanism of stretch activation is unknown. We investigated the role of recently observed connections between myosin and troponin, called “troponin bridges,” by analyzing real-time X-ray diffraction “movies” from sinusoidally stretch-activated Lethocerus muscles. Observed changes in X-ray reflections arising from myosin heads, actin filaments, troponin, and tropomyosin were consistent with the hypothesis that troponin bridges are the key agent of mechanical signal transduction. The time-resolved sequence of molecular changes suggests a mechanism for stretch activation, in which troponin bridges mechanically tug tropomyosin aside to relieve tropomyosin’s steric blocking of myosin–actin binding. This enables subsequent force production, with cross-bridge targeting further enhanced by stretch-induced lattice compression and thick-filament twisting. Similar linkages may operate in other muscle systems, such as mammalian cardiac muscle, where stretch activation is thought to aid in cardiac ejection. PMID:21148419

Parallel evolution of chordate cis-regulatory code for development.

PubMed

Doglio, Laura; Goode, Debbie K; Pelleri, Maria C; Pauls, Stefan; Frabetti, Flavia; Shimeld, Sebastian M; Vavouri, Tanya; Elgar, Greg

2013-11-01

Urochordates are the closest relatives of vertebrates and at the larval stage, possess a characteristic bilateral chordate body plan. In vertebrates, the genes that orchestrate embryonic patterning are in part regulated by highly conserved non-coding elements (CNEs), yet these elements have not been identified in urochordate genomes. Consequently the evolution of the cis-regulatory code for urochordate development remains largely uncharacterised. Here, we use genome-wide comparisons between C. intestinalis and C. savignyi to identify putative urochordate cis-regulatory sequences. Ciona conserved non-coding elements (ciCNEs) are associated with largely the same key regulatory genes as vertebrate CNEs. Furthermore, some of the tested ciCNEs are able to activate reporter gene expression in both zebrafish and Ciona embryos, in a pattern that at least partially overlaps that of the gene they associate with, despite the absence of sequence identity. We also show that the ability of a ciCNE to up-regulate gene expression in vertebrate embryos can in some cases be localised to short sub-sequences, suggesting that functional cross-talk may be defined by small regions of ancestral regulatory logic, although functional sub-sequences may also be dispersed across the whole element. We conclude that the structure and organisation of cis-regulatory modules is very different between vertebrates and urochordates, reflecting their separate evolutionary histories. However, functional cross-talk still exists because the same repertoire of transcription factors has likely guided their parallel evolution, exploiting similar sets of binding sites but in different combinations.

The amphioxus genome and the evolution of the chordate karyotype

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

Putnam, Nicholas H.; Butts, Thomas; Ferrier, David E.K.

2008-04-01

Lancelets ('amphioxus') are the modern survivors of an ancient chordate lineage with a fossil record dating back to the Cambrian. We describe the structure and gene content of the highly polymorphic {approx}520 million base pair genome of the Florida lancelet Branchiostoma floridae, and analyze it in the context of chordate evolution. Whole genome comparisons illuminate the murky relationships among the three chordate groups (tunicates, lancelets, and vertebrates), and allow reconstruction of not only the gene complement of the last common chordate ancestor, but also a partial reconstruction of its genomic organization, as well as a description of two genome-wide duplicationsmore » and subsequent reorganizations in the vertebrate lineage. These genome-scale events shaped the vertebrate genome and provided additional genetic variation for exploitation during vertebrate evolution.« less

Trampolines, children, and strokes.

PubMed

Wechsler, B; Kim, H; Hunter, J

2001-08-01

Strokes in children related to sports injuries are rare, but pediatric trampoline injuries are dramatically increasing. Minor trauma to the vulnerable extracranial vertebral arteries as they travel superficially through the dorsum of the neck can begin a cascade of events that results in arterial dissection, thrombus formation, and embolization with cerebral infarction. We present the case of an 11-yr-old boy who developed left vertebral artery dissection subsequent to a trampoline injury.

Reproductive costs in terrestrial male vertebrates: insights from bird studies

PubMed Central

Gamelon, Marlène; Sæther, Bernt-Erik

2016-01-01

Reproduction requires resources that cannot be allocated to other functions resulting in direct reproductive costs (i.e. trade-offs between current reproduction and subsequent survival/reproduction). In wild vertebrates, direct reproductive costs have been widely described in females, but their occurrence in males remains to be explored. To fill this gap, we gathered 53 studies on 48 species testing direct reproductive costs in male vertebrates. We found a trade-off between current reproduction and subsequent performances in 29% of the species and in every clade. As 73% of the studied species are birds, we focused on that clade to investigate whether such trade-offs are associated with (i) levels of paternal care, (ii) polygyny or (iii) pace of life. More precisely for this third question, it is expected that fast species (i.e. short lifespan, early maturity, high fecundity) pay a cost in terms of survival, whereas slow species (with opposite characteristics) do so in terms of fecundity. Our findings tend to support this hypothesis. Finally, we pointed out the potential confounding effects that should be accounted for when investigating reproductive costs in males and strongly encourage the investigation of such costs in more clades to understand to what extent our results are relevant for other vertebrates. PMID:26791619

Vertebral Development in Paleozoic and Mesozoic Tetrapods Revealed by Paleohistological Data

PubMed Central

Danto, Marylène; Witzmann, Florian; Fröbisch, Nadia B.

2016-01-01

Basal tetrapods display a wide spectrum of vertebral centrum morphologies that can be used to distinguish different tetrapod groups. The vertebral types range from multipartite centra in stem-tetrapods, temnospondyls, and seymouriamorphs up to monospondylous centra in lepospondyls and have been drawn upon for reconstructing major evolutionary trends in tetrapods that are now considered textbook knowledge. Two modes of vertebral formation have been postulated: the multipartite vertebrae formed first as cartilaginous elements with subsequent ossification. The monospondylous centrum, in contrast, was formed by direct ossification without a cartilaginous precursor. This study describes centrum morphogenesis in basal tetrapods for the first time, based on bone histology. Our results show that the intercentra of the investigated stem-tetrapods consist of a small band of periosteal bone and a dense network of endochondral bone. In stereospondyl temnospondyls, high amounts of calcified cartilage are preserved in the endochondral trabeculae. Notably, the periosteal region is thickened and highly vascularized in the plagiosaurid stereospondyls. Among “microsaur” lepospondyls, the thickened periosteal region is composed of compact bone and the notochordal canal is surrounded by large cell lacunae. In nectridean lepospondyls, the periosteal region has a spongy structure with large intertrabecular spaces, whereas the endochondral region has a highly cancellous structure. Our observations indicate that regardless of whether multipartite or monospondylous, the centra of basal tetrapods display first endochondral and subsequently periosteal ossification. A high interspecific variability is observed in growth rate, organization, and initiation of periosteal ossification. Moreover, vertebral development and structure reflect different lifestyles. The bottom-dwelling Plagiosauridae increase their skeletal mass by hyperplasy of the periosteal region. In nectrideans, the skeletal mass decreases, as the microstructure is spongy and lightly built. Additionally, we observed that vertebral structure is influenced by miniaturization in some groups. The phylogenetic information that can be drawn from vertebral development, however, is limited. PMID:27074015

Evaluation of patients with a recent clinical fracture and osteoporosis, a multidisciplinary approach

PubMed Central

Dumitrescu, Bianca; van Helden, Svenjhalmar; ten Broeke, Rene; Nieuwenhuijzen-Kruseman, Arie; Wyers, Caroline; Udrea, Gabriela; Linden, Sjef van der; Geusens, Piet

2008-01-01

The aetiology of osteoporotic fractures is multifactorial, but little is known about the way to evaluate patients with a recent clinical fracture for the presence of secondary osteoporosis. The purpose of this study was to determine the prevalence of contributors to secondary osteoporosis in patients presenting with a clinical vertebral or non-vertebral fracture. Identifying and correcting these contributors will enhance treatment effect aimed at reducing the risk of subsequent fractures. In a multidisciplinary approach, including evaluation of bone and fall-related risk factors, 100 consecutive women (n = 73) and men (n = 27) older than 50 years presenting with a clinical vertebral or non-vertebral fracture and having osteoporosis (T-score ≤-2.5) were further evaluated clinically and by laboratory testing for the presence of contributors to secondary osteoporosis. In 27 patients, 34 contributors were previously known, in 50 patients 52 new contributors were diagnosed (mainly vitamin D deficiency in 42) and 14 needed further exploration because of laboratory abnormalities (mainly abnormal thyroid stimulating hormone in 9). The 57 patients with contributors were older (71 vs. 64 yrs, p < 0.01), had more vertebral deformities (67% vs. 44%, p < 0.05) and a higher calculated absolute 10-year risk for major (16.5 vs. 9.9%, p < 0.01) and for hip fracture (6.9 vs. 2.4%, p < 0.01) than patients without contributors. The presence of contributors was similar between women and men and between patients with fractures associated with a low or high-energy trauma. We conclude that more than one in two patients presenting with a clinical vertebral or non-vertebral fracture and BMD-osteoporosis have secondary contributors to osteoporosis, most of which were correctable. Identifying and correcting these associated disorders will enhance treatment effect aimed at reducing the risk of subsequent fractures in patients older than 50 years. PMID:18680609

Vertebral artery pexy for microvascular decompression of the facial nerve in the treatment of hemifacial spasm.

PubMed

Ferreira, Manuel; Walcott, Brian P; Nahed, Brian V; Sekhar, Laligam N

2011-06-01

Hemifacial spasm (HFS) is caused by arterial or venous compression of cranial nerve VII at its root exit zone. Traditionally, microvascular decompression of the facial nerve has been an effective treatment for posterior inferior and anterior inferior cerebellar artery as well as venous compression. The traditional technique involves Teflon felt or another construct to cushion the offending vessel from the facial nerve, or cautery and division of the offending vein. However, using this technique for severe vertebral artery (VA) compression can be ineffective and fraught with complications. The authors report the use of a new technique of VA pexy to the petrous or clival dura mater in patients with HFS attributed to a severely ectatic and tortuous VA, and detail the results in a series of patients. Six patients with HFS due to VA compression underwent a retrosigmoid craniotomy, combined with a far-lateral approach in some patients. On identification of the site of VA compression, the vessel was mobilized adequately for the decompression. Great care was taken to avoid kinking the perforating vessels arising from the VA. Two 8-0 nylon sutures were passed through to the wall of the VA and then through the clival or petrous dura, and then tied to alleviate compression on cranial nerve VII. Patients were followed for at least 1 year postoperatively (mean 2.7 years, range 1-4 years). All 6 patients had complete resolution of their HFS. Facial function was tested postoperatively, and was stable when compared with the preoperative baseline. Two of the 3 patients with preoperative tinnitus had resolution of this symptom after the procedure. Postoperative imaging demonstrated VA decompression of the facial nerve and no evidence of stroke in all patients. One patient suffered from hearing loss, another developed a postoperative transient unilateral vocal cord paralysis, and a third patient developed a pseudomeningocele that resolved with the placement of a lumbar drain. Hemifacial spasm and other neurovascular syndromes are effectively treated by repositioning the compressing artery. Careful study of the preoperative MR images may identify a select group of patients with HFS due to an ectatic VA. Rather than traditional decompression with only pledget placement, these patients may benefit from a VA pexy to provide an effective, safe, and durable resolution of their symptoms while minimizing surgical complications.

Prevalent vertebral deformities predict increased mortality and increased fracture rate in both men and women: a 10-year population-based study of 598 individuals from the Swedish cohort in the European Vertebral Osteoporosis Study.

PubMed

Hasserius, R; Karlsson, M K; Nilsson, B E; Redlund-Johnell, I; Johnell, O

2003-01-01

The aim of this study was to evaluate whether a prevalent vertebral deformity predicts mortality and fractures in both men and women. In the city of Malmö, 598 individuals (298 men, 300 women; age 50-80 years) were selected from the city's population and were included in the Swedish part of the European Vertebral Osteoporosis Study (EVOS). At baseline the participants answered a questionnaire and lateral spine radiographs were performed. The prevalence of subjects with vertebral deformity was assessed using a morphometric method. The mortality during a 10-year follow-up period was determined through the register of the National Swedish Board of Health and Welfare. Eighty-five men and 43 women died during the study period. The subsequent fracture incidence during the follow-up period was ascertained by postal questionnaires, telephone interviews and by a survey of the archives of the Department of Radiology in the city hospital. Thirty-seven men and 69 women sustained a fracture during the study period. Data are presented as hazard ratios (HR) with 95% confidence interval (95% CI) within brackets. Prevalent vertebral deformity, defined as a reduction by more than 3 standard deviations (SD) in vertebral height ratio, predicted mortality during the forthcoming decade in both men [age-adjusted HR 2.4 (95% CI 1.6-3.9)] and women [age-adjusted HR 2.3 (95% CI 1.3-4.3)]. In men there was an increased mortality due to cardiovascular and pulmonary diseases and in women due to cancer. Prevalent vertebral deformity predicted an increased risk of any fracture during the forthcoming decade in both men [age-adjusted HR 2.7 (95% CI 1.4-5.3)] and women [age-adjusted HR 1.8 (95% CI 1.1-2.9)]. Prevalent vertebral deformity predicted an increased risk of any subsequent fragility fracture in women [age-adjusted HR 2.0 (95% CI 1.1-3.5)]; however, in men the increased risk was nonsignificant [age-adjusted HR 1.9 (95% CI 0.7-5.1)]. In summary, a prevalent vertebral deformity can predict both increased mortality and increased fracture incidence during the following decade in both men and women. We conclude that prevalent vertebral deformity could be used as a risk factor in both genders for mortality and future fracture.

Long-term effects of vertebroplasty: adjacent vertebral fractures.

PubMed

Baroud, Gamal; Vant, Christianne; Wilcox, Ruth

2006-01-01

In today's aging population, osteoporosis-related fractures are an ever-growing concern. Vertebroplasty, a promising yet cost-effective treatment for vertebral compression fractures, has an increasing role. The first vertebroplasty procedures were reported by Deramond and Galibert in France in 1987, and international interest grew with continued development of clinical techniques and augmentation materials in Europe and the United States. Initial publications and presentations at peer review meetings demonstrated 60-90% success rates in providing immediate and significant pain relief. The objective of this review is to assemble experimental and computational biomechanical research whose goal is determining and preventing the negative long-term effects ofvertebroplasty, with a specific focus on adjacent vertebral fractures. Biomechanical studies using isolated cancellous bone cylinders have shown that osteoporotic cancellous bone samples augmented by the rigid bone cement were at least 12 times stiffer and 35 times stronger than the untreated osteoporotic cancellous bone samples. The biomechanical efficacy of the procedure to repair the fractured vertebrae and prevent further collapse is determined using single-vertebra models. The strength or load-bearing capacity of a single vertebra is significantly increased following augmentation when compared to the intact strength. However, there is no dear result regarding the overall stiffness of the single vertebra, with studies reporting contradictorily that the stiffness increases, decreases, or does not significantly alter following augmentation. The effects of vertebroplasty on adjacent structures are studied via multisegment models, whose results plainly oppose the findings of the single-vertebra and intravertebral models. Here, augmentation was shown to decrease the overall segment strength by 19% when compared to the matched controls. As well, there is a significant increase in disc pressure compared to the pre-augmentation measurements. This translates to a high hydrostatic pressure adjacent to the augmented vertebra, representing the first evidence of increased loading. Computational finite element (FE) models have found that the rigid cement augmentation results in an increase in loading in the structures adjacent to the augmented vertebra. The mechanism of the increase of the loading is predicted to be the pillar effect of the rigid cement. The cement inhibits the normal endplate bulge into the augmented vertebra and thus pressurizes the adjacent disc, which subsequently increases the loading of the untreated vertebra. The mechanism for adjacent vertebral fractures is still unclear, but from experimental and computational studies, it appears that the change in mechanical loading following augmentation is responsible. The pillar effect of injected cement is hypothesized to decrease the endplate bulge in the augmented vertebra causing an increase in adjacent disc pressure that is communicated to the adjacent vertebra. To confirm the viability of the pillar effect as the responsible mechanism, endplate bulge and disc pressure should be directly measured before and after augmentation. Future studies should be concerned with quantifying the current and ideal mechanical response of the spine and subsequently developing cements that can achieve this optimum response.

Extraosseous Extension of Aggressive Vertebral Hemangioma as a Potential Pitfall on 68Ga-PSMA PET/CT.

PubMed

Probst, Stephan; Bladou, Franck; Abikhzer, Gad

2017-08-01

A 74-year-old man with newly diagnosed prostate cancer underwent Ga-PSMA PET/CT, which demonstrated intense uptake in and adjacent the L2 vertebral body. Subsequent MRI of the lumbar spine showed an aggressive L2 hemangioma with adjacent soft tissue extension. There was congruence of the intraosseous and extraosseous components of the hemangioma and the PSMA PET uptake. This is a rare but important potential pitfall in Ga-PSMA PET/CT-a soft tissue lesion with intense tracer uptake related not to a nodal metastasis of prostate cancer but to extraosseous extension of an aggressive vertebral body hemangioma.

Cervical vertebral anomalies in patients with anomalies of the head and neck.

PubMed

Manaligod, J M; Bauman, N M; Menezes, A H; Smith, R J

1999-10-01

Congenital head and neck anomalies can occur in association with vertebral anomalies, particularly of the cervical vertebrae. While the former are easily recognized, especially when part of a syndrome, the latter are often occult, thereby delaying their diagnosis. The presence of vertebral anomalies must be considered in pediatric patients with head and neck abnormalities to expedite management of select cases and to prevent neurologic injury. We present our experience with 5 pediatric patients who were referred to the Department of Otolaryngology-Head and Neck Surgery at the University of Iowa with a variety of syndromic anomalies of the head and neck. Each patient was subsequently also found to have a vertebral anomaly. The relevant embryogenesis of the anomalous structures is discussed, with highlighting of potential causes such as teratogenic agents and events and germ-line mutations. A review of syndromes having both head and neck and vertebral anomalies is presented to heighten awareness of otolaryngologists evaluating children with syndromic disorders. Finally, the findings on radiographic imaging studies, particularly computed tomography, are discussed to facilitate the prompt diagnosis of vertebral anomalies.

Giant rhinoceros Paraceratherium and other vertebrates from Oligocene and middle Miocene deposits of the Kağızman-Tuzluca Basin, Eastern Turkey.

PubMed

Sen, Sevket; Antoine, Pierre-Olivier; Varol, Baki; Ayyildiz, Turhan; Sözeri, Koray

2011-05-01

A recent fieldwork in the Kağızman-Tuzluca Basin in northeastern Turkey led us to the discovery of three vertebrate localities which yielded some limb bones of the giant rhino Paraceratherium, a crocodile tooth, and some small mammals, respectively. These discoveries allowed, for the first time to date some parts of the sedimentary units of this basin. This study also shows that the dispersal area of Paraceratherium is wider than it was known before. Eastern Turkey has several Cenozoic sedimentary basins formed during the collision of the Arabian and Eurasian plates. They are poorly documented for vertebrate paleontology. Consequently, the timing of tectonic activities, which led to the formation of the East Anatolian accretionary complex, is not constrained enough with a solid chronological framework. This study provides the first biostratigraphic evidences for the infill under the control of the compressive tectonic regime, which built the East Anatolian Plateau.

Static and dynamic balance performance in patients with osteoporotic vertebral compression fracture.

PubMed

Wang, Ling-Yi; Liaw, Mei-Yun; Huang, Yu-Chi; Lau, Yiu-Chung; Leong, Chau-Peng; Pong, Ya-Ping; Chen, Chia-Lin

2013-01-01

Patients with osteoporotic vertebral compression fracture (OVCF) have postural changes and increased risk of falling. The aim of this study is to compare balance characteristics between patients with OVCF and healthy control subjects. Patients with severe OVCF and control subjects underwent computerised dynamic posturography (CDP) in this case-control study. Forty-seven OVCF patients and 45 controls were recruited. Compared with the control group, the OVCF group had significantly decreased average stability; maximal stability under the `eye open with swayed support surface' (CDP subtest 4) and 'eye closed with swayed support surface' conditions (subtest 5); and decreased ankle strategy during subtests 4 and 5 and under the `swayed vision with swayed support surface' condition (subtest 6). The OVCF group fell more frequently during subtests 5 and 6 and had longer overall reaction time and longer reaction time when moving backward during the directional control test. OVCF patients had poorer static and dynamic balance performance compared with normal control. They had decreased postural stability and ankle strategy with increased fall frequency on a swayed surface; they also had longer reaction times overall and in the backward direction. Therefore, we suggest balance rehabilitation for patients with OVCF to prevent fall.

Less invasive reduction and fusion of fresh A2 and A 3 traumatic L 1-L 4 fractures with a novel vertebral body augmentation implant and short pedicle screw fixation and fusion.

PubMed

Korovessis, Panagiotis; Vardakastanis, Konstantinos; Repantis, Thomas; Vitsas, Vasilios

2014-04-01

The aim of this clinical study was to report on the efficacy in reduction and safety in PMMA leakage of a novel vertebral augmentation technique with PEEK and PMMA, together with pedicle screws in the treatment of fresh vertebral fractures in young adults. Twenty consecutive young adults aged 45 ± 11 years with fresh burst A3/AO or severely compressed A2/AO fractures underwent via a less invasive posterior approach one-staged reduction with a novel augmentation implant and PMMA plus 3-vertebrae pedicle screw fixation and fusion. Radiologic parameters as segmental kyphosis (SKA), anterior (AVBHr) and posterior vertebral body height ratio (PVBHr), spinal canal encroachment (SCE), cement leakage and functional parameters as VAS, SF-36 were measured pre- and post-operatively. Hybrid construct restored AVBHr (P < 0.000), PVBHr (P = 0.02), SKA (P = 0.015), SCE (P = 0.002) without loss of correction at an average follow-up of 17 months. PMMA leakage occurred in 3 patients (3 vertebrae) either anteriorly to the fractured vertebral body or to the adjacent disc, but in no case to the spinal canal. Two pedicle screws were malpositioned (one medially, one laterally to the pedicle at the fracture level) without neurologic sequelae. Solid posterolateral spinal fusion occurred 8-10 months post-operatively. Pre-operative VAS and SF-36 scores improved post-operatively significantly. This study showed that this novel vertebral augmentation technique using PEEK implant and PMMA reduces and stabilizes via less invasive technique A2 and A3 vertebral fractures without loss of correction and leakage to the spinal canal.

C1-C2 instability with severe occipital headache in the setting of vertebral artery facet complex erosion.

PubMed

Taher, Fadi; Bokums, Kristaps; Aichmair, Alexander; Hughes, Alexander P

2014-05-01

An exact understanding of patient vertebral artery anatomy is essential to safely place screws at the atlanto-axial level in posterior arthrodesis. We aim to report a case of erosion of the left vertebral artery into the C1-C2 facet complex with resultant rotatory and lateral listhesis presenting with severe occipital headache. This represents a novel etiology for this diagnosis and our report illustrates technical considerations when instrumenting the C1-C2 segment. We report a case of severe occipital headache due to C1-C2 instability with resultant left C2 nerve compression in the setting of erosion of the vertebral artery into the C1-C2 facet complex. A 68-year-old woman presented with a 12-month history of progressively debilitating headache and neck pain with atlanto-axial instability. Computed tomography (CT) angiography demonstrated erosion of the left vertebral artery into the left C1-C2 facet complex. In addition, the tortuous vertebral arteries had eroded into the C2 pedicles, eliminating the possibility for posterior pedicle screw placement. The patient underwent posterior arthrodesis of C1-C2 utilizing bilateral lateral mass fixation into C1 and bilateral trans-laminar fixation into C2 with resolution of all preoperative complaints. This study constitutes the first report of a tortuous vertebral artery causing the partial destruction of a C1-C2 facet complex, as well as instability, with the clinical presentation of severe occipital headache. It hereby presents a novel etiology for both the development of C1-C2 segment instability as well as the development of occipital headache. Careful evaluation of such lesions utilizing CT angiography is important when formulating a surgical plan.

Brain infarction due to vertebral artery dissection caused by a bone protrusion from the condylar fossa in a juvenile case.

PubMed

Fujii, Mutsumi; Ohgushi, Miki; Chin, Takaaki

2018-02-06

A 16-year-old boy presented with multiple posterior circulation ischemic strokes resulting from vertebral artery (VA) dissection. Three-dimensional computed tomography showed aberrant sub-occipital bone protuberance, proximal to the VA dissection. Since the patient was a habitual neck cracker, VA dissection was thought to result from the impact shock of the rotational head movement. This could be due to either the osseous prominence or the compression between the prominence and the C1. Although it is a rare etiology of Bow Hunter's syndrome, VA dissection due to sub-occipital bone spur because of neck cracking should be considered in the diagnosis of Bow Hunter's syndrome in juvenile patients.

Double Aortic Arch With Previously Undescribed Head and Neck Vessel Branching.

PubMed

Hashemi, Sassan; Parks, W James; Sallee, Denver; Slesnick, Timothy

2017-04-01

Vascular ring in the form of a double aortic arch is a rare anomaly that can cause airway compression. It occasionally occurs with unusual head and neck vessel branching. A 5-year-old boy with chronic respiratory symptoms was referred because of a tracheal indentation on his chest x-ray. Magnetic resonance imaging showed a double aortic arch with arch origins of a common carotid, vertebral, and subclavian on the right and internal and external carotids, vertebral, and subclavian arteries on the left. Our case represents, to our knowledge, the first report of a double aortic arch with 7 separate vessels arising from the transverse arches. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Impact of gene gains, losses and duplication modes on the origin and diversification of vertebrates.

PubMed

Cañestro, Cristian; Albalat, Ricard; Irimia, Manuel; Garcia-Fernàndez, Jordi

2013-02-01

The study of the evolutionary origin of vertebrates has been linked to the study of genome duplications since Susumo Ohno suggested that the successful diversification of vertebrate innovations was facilitated by two rounds of whole-genome duplication (2R-WGD) in the stem vertebrate. Since then, studies on the functional evolution of many genes duplicated in the vertebrate lineage have provided the grounds to support experimentally this link. This article reviews cases of gene duplications derived either from the 2R-WGD or from local gene duplication events in vertebrates, analyzing their impact on the evolution of developmental innovations. We analyze how gene regulatory networks can be rewired by the activity of transposable elements after genome duplications, discuss how different mechanisms of duplication might affect the fate of duplicated genes, and how the loss of gene duplicates might influence the fate of surviving paralogs. We also discuss the evolutionary relationships between gene duplication and alternative splicing, in particular in the vertebrate lineage. Finally, we discuss the role that the 2R-WGD might have played in the evolution of vertebrate developmental gene networks, paying special attention to those related to vertebrate key features such as neural crest cells, placodes, and the complex tripartite brain. In this context, we argue that current evidences points that the 2R-WGD may not be linked to the origin of vertebrate innovations, but to their subsequent diversification in a broad variety of complex structures and functions that facilitated the successful transition from peaceful filter-feeding non-vertebrate ancestors to voracious vertebrate predators. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cardiac compression due to gastric volvulus: an unusual cause of chest pain.

PubMed

Brown, Alex; Austin, David; Kanakala, Venkatesh

2017-05-22

A 42-year-old man was admitted to coronary care for assessment with severe retrosternal chest pain. Echocardiography showed significant external compression of the left atrium. A subsequent CT scan revealed him to have a large hiatus hernia, with most of his stomach herniating into his thorax causing left atrial compression and gastric volvulus. He subsequently underwent successful emergency decompression of the gastric volvulus and repair of his hiatus hernia. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Biomechanical Evaluation of an Injectable and Biodegradable Copolymer P(PF-co-CL) in a Cadaveric Vertebral Body Defect Model

PubMed Central

Fang, Zhong; Giambini, Hugo; Zeng, Heng; Camp, Jon J.; Dadsetan, Mahrokh; Robb, Richard A.; An, Kai-Nan; Yaszemski, Michael J.

2014-01-01

A novel biodegradable copolymer, poly(propylene fumarate-co-caprolactone) [P(PF-co-CL)], has been developed in our laboratory as an injectable scaffold for bone defect repair. In the current study, we evaluated the ability of P(PF-co-CL) to reconstitute the load-bearing capacity of vertebral bodies with lytic lesions. Forty vertebral bodies from four fresh-frozen cadaveric thoracolumbar spines were used for this study. They were randomly divided into four groups: intact vertebral body (intact control), simulated defect without treatment (negative control), defect treated with P(PF-co-CL) (copolymer group), and defect treated with poly(methyl methacrylate) (PMMA group). Simulated metastatic lytic defects were made by removing a central core of the trabecular bone in each vertebral body with an approximate volume of 25% through an access hole in the side of the vertebrae. Defects were then filled by injecting either P(PF-co-CL) or PMMA in situ crosslinkable formulations. After the spines were imaged with quantitative computerized tomography, single vertebral body segments were harvested for mechanical testing. Specimens were compressed until failure or to 25% reduction in body height and ultimate strength and elastic modulus of each specimen were then calculated from the force–displacement data. The average failure strength of the copolymer group was 1.83 times stronger than the untreated negative group and it closely matched the intact vertebral bodies (intact control). The PMMA-treated vertebrae, however, had a failure strength 1.64 times larger compared with the intact control. The elastic modulus followed the same trend. This modulus mismatch between PMMA-treated vertebrae and the host vertebrae could potentially induce a fracture cascade and degenerative changes in adjacent intervertebral discs. In contrast, P(PF-co-CL) restored the mechanical properties of the treated segments similar to the normal, intact, vertebrae. Therefore, P(PF-co-CL) may be a suitable alternative to PMMA for vertebroplasty treatment of vertebral bodies with lytic defects. PMID:24256208

Dynamic Response of Vertebral Elements Related to USAF Injury

DTIC Science & Technology

1978-02-01

eventual loss of mucopolysaccharide matrix from both the hyaline cartilage end plates and fibro- cartilage annulUS« resulting in increased cell...In other studies conducted during this contract period, seven adult Rhesus monkeys have been subjected to implantations of calibrated stress...fibroblasts; 2. Loss of cells from and compression of the circular regions lying between the cartilage end plates and nucleus; 3. Altered staining and

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

Abboud, Georges, E-mail: drgeorgesabboud@hotmail.com; Midulla, Marco, E-mail: marcomidu@gmail.com; Lions, Christophe, E-mail: c-lions@chru-lille.fr

The May-Thurner syndrome is a well-known anatomical anomaly where the left common iliac vein (LCIV) is compressed between the right common iliac artery and the fifth vertebral body. This report describes the case of a 'right-sided' May-Thurner syndrome where the right common iliac vein (RCIV) is compressed by the left common iliac artery in a patient with a left-sided inferior vena cava (IVC). A 26-year-old woman was admitted to our institution with acute edema of the right lower limb. The diagnosis of May-Thurner syndrome was done by CT scan and confirmed by phlebography. An endovascular treatment with stenting was carriedmore » out, with good patency and clinical result at 12-month follow-up.« less

Evolution of the new vertebrate head by co-option of an ancient chordate skeletal tissue.

PubMed

Jandzik, David; Garnett, Aaron T; Square, Tyler A; Cattell, Maria V; Yu, Jr-Kai; Medeiros, Daniel M

2015-02-26

A defining feature of vertebrates (craniates) is a pronounced head that is supported and protected by a robust cellular endoskeleton. In the first vertebrates, this skeleton probably consisted of collagenous cellular cartilage, which forms the embryonic skeleton of all vertebrates and the adult skeleton of modern jawless and cartilaginous fish. In the head, most cellular cartilage is derived from a migratory cell population called the neural crest, which arises from the edges of the central nervous system. Because collagenous cellular cartilage and neural crest cells have not been described in invertebrates, the appearance of cellular cartilage derived from neural crest cells is considered a turning point in vertebrate evolution. Here we show that a tissue with many of the defining features of vertebrate cellular cartilage transiently forms in the larvae of the invertebrate chordate Branchiostoma floridae (Florida amphioxus). We also present evidence that during evolution, a key regulator of vertebrate cartilage development, SoxE, gained new cis-regulatory sequences that subsequently directed its novel expression in neural crest cells. Together, these results suggest that the origin of the vertebrate head skeleton did not depend on the evolution of a new skeletal tissue, as is commonly thought, but on the spread of this tissue throughout the head. We further propose that the evolution of cis-regulatory elements near an ancient regulator of cartilage differentiation was a major factor in the evolution of the vertebrate head skeleton.

DISCUSSION ON SPINAL INJURIES

PubMed Central

1928-01-01

(1).—Varieties of spinal injuries, the three groups of common usage: fractures, dislocations, fracture-dislocations. Shall not refer in detail to fractures of the spinous or transverse processes. (2) Mechanics of injury to vertebræ. Two variables: (1) the nature of the bones; (2) the qualities of the force. Spinal injury usually caused by indirect violence. (3) The different results of injuries applied to the head; may break skull, failing that, the neck. Atlas fracture. Difference in qualities of the force causing atlas fracture and low cervical dislocation. (4) The compound nature of the vertebral body. The two columns, anterior, spongy; posterior, compact. The nature of wedge-compression of the vertebral body. Variations in the shape of the wedge. Reasons. Occur at all levels, including cervical spine. (5) Frequency of injury at different levels of vertebral column. “Localization” of injury. The two places of the graph of injury. The cervical at C. 5. Reason. The thoracic-lumbar peak at T. 12, L. 1 industrial. Is there a third peak at C. 2? (6) The effects of violent flexion of the spine: cervical flexion causes luxation at C. 5 or so. Extension causes fracture of odontoid. Violent flexion and extension therefore cause injury at very different levels. Thoracic region, why is there no “peak” of injury at T.6, 7? Lumbar region. (7) Displacement of fragments. Continuation of violence after the essential injury has been effected. Kümmell's disease, no inflammatory process involved. (8) Injury to the intervertebral discs, essential for displacement. Imperfect rupture a cause for difficulty in reducing luxations. The worst cases those in which it is most easily done, but most of these have cord damage. (9) Spinal injury from minimal violence. Examples of trivial cases, diving, brushing hair and so forth. Vertebral displacement in disease a much more serious thing. (10) Curious stability of many cervical luxations. Reasons. Locking of the inferior zygaphophyses. (11) Injury to nervous elements left principally to other speakers. Cord compression very rare. Immediate and irremediable damage. Root injuries. Falling mortality of modern statistics due to better diagnosis. (12) Primary operation for fractures of spine relegated to oblivion. Rarity of indications for open operation. Reduction the best treatment. ImagesFig. 5Fig. 6 PMID:19986314

Usefulness of prone cross-table lateral radiographs in vertebral compression fractures.

PubMed

Cho, Jae Hwan; Shin, Sang Ik; Lee, Jae Hyup; Yeom, Jin Sup; Chang, Bong-Soon; Lee, Choon-Ki

2013-09-01

Dynamic radiographs are recommended to investigate non-healing evidence such as the dynamic mobility or intravertebral clefts in osteoporotic vertebral compression fractures (VCFs). However, it is difficult to examine standing flexion and extension lateral radiographs due to severe pain. The use of prone cross-table lateral radiographs (PrLRs) as a diagnostic tool has never been proposed to our knowledge. The purpose of this study is to clarify the usefulness of PrLRs in diagnosis and treatment of VCFs. We reviewed 62 VCF patients examined with PrLRs between January 1, 2008 and June 30, 2011. To compare the degree of pain provoked between standing extension lateral radiographs (StLRs) and PrLRs, numeric rating scale (NRS) scores were assessed and compared by a paired t-test. Vertebroplasty was done for 40 patients and kyphoplasty was done for 9 patients with routine manners. To assess the degree of postural reduction, vertebral wedge angles (VWA) and vertebral height ratios (VHR) were calculated by using preoperative StLRs, PrLRs, and postoperative lateral radiographs. Two variables derived from changes in VWA and VHR between preoperative and postoperative radiographs were compared by a paired t-test. The average NRS scores were 6.23 ± 1.67 in StLRs and 5.18 ± 1.47 in PrLRs. The degree of pain provocation was lower in using PrLRs than StLRs (p < 0.001). The average changes of VWA between preoperative and postoperative status were 5.24° ± 6.16° with PrLRs and 3.46° ± 3.47° with StLRs. The average changes of VHR were 0.248 ± 0.178 with PrLRs and 0.148 ± 0.161 with StLRs. The comparisons by two variables showed significant differences for both parameters (p = 0.021 and p < 0.001, respectively). The postoperative radiological status was reflected more precisely when using PrLRs than StLRs. In comparison with StLR, the PrLR was more accurate in predicting the degree of restoration of postoperative vertebral heights and wedge angles, and provoked less pain during examination. The PrLR could be a useful diagnostic tool to detect intravertebral cleft or intravertebral dynamic instability.

Decreased fracture rate, pharmacogenetics and BMD response in 79 Swedish children with osteogenesis imperfecta types I, III and IV treated with Pamidronate.

PubMed

Lindahl, K; Kindmark, A; Rubin, C-J; Malmgren, B; Grigelioniene, G; Söderhäll, S; Ljunggren, Ö; Åström, E

2016-06-01

Osteogenesis imperfecta (OI) is an inherited heterogeneous bone fragility disorder, usually caused by collagen I mutations. It is well established that bisphosphonate treatment increases lumbar spine (LS) bone mineral density (BMD), as well as improves vertebral geometry in severe OI; however, fracture reduction has been difficult to prove, pharmacogenetic studies are scarce, and it is not known at which age, or severity of disease, treatment should be initiated. COL1A1 and COL1A2 were analyzed in 79 children with OI (type I n=33, type III n=25 and type IV n=21) treated with Pamidronate. Data on LS BMD, height, and radiologically confirmed non-vertebral and vertebral fractures were collected prior to, and at several time points during treatment. An increase in LS BMD Z-score was observed for all types of OI, and a negative correlation to Δ LS BMD was observed for both age and LS BMD Z-score at treatment initiation. Supine height Z-scores were not affected by Pamidronate treatment, The fracture rate was reduced for all OI types at all time points during treatment (overall p<0.0003, <0.0001 and 0.0003 for all OI types I, III and IV respectively). The reduced fracture rate was maintained for types I and IV, while an additional decrease was observed over time for type III. The fracture rate was reduced also in individuals with continued low BMD after >4yrs Pamidronate. Twice as many boys as girls with OI type I were treated with Pamidronate, and the fracture rate the year prior treatment was 2.2 times higher for boys (p=0.0236). Greater Δ LS BMD, but smaller Δ fracture numbers were observed on Pamidronate for helical glycine mutations in COL1A1 vs. COL1A2. Vertebral compression fractures did not progress in any individual during treatment; however, they did not improve in 9%, and these individuals were all >11years of age at treatment initiation (p<0.0001). Pamidronate treatment in children with all types of OI increased LS BMD, decreased fracture rate, and improved vertebral compression fractures. Fracture reduction was prompt and maintained during treatment, irrespective of age at treatment initiation and collagen I mutation type. Copyright © 2016 Elsevier Inc. All rights reserved.

Numerical Assessment of the Role of Slip and Twinning in Magnesium Alloy AZ31B During Loading Path Reversal

NASA Astrophysics Data System (ADS)

Wang, Huamiao; Wu, Peidong; Wang, Jian

2015-07-01

Magnesium alloy AZ31B plastically deforms via twinning and slip. Corresponding to the unidirectional nature of twinning, the activity of twinning/detwinning is directly related to loading history and materials texture. Using the elastic viscoplastic self-consistent model implementing with the twinning and detwinning model (EVPSC-TDT), we revisited experimental data of AZ31B sheets under four different strain paths: (1) tension-compression-tension along rolling direction, (2) tension-compression-tension along transverse direction, (3) compression-tension-compression along rolling direction, and (4) compression-tension-compression along transverse direction, and identified the dominant deformation mechanisms with respect to the strain path. We captured plastic deformation behaviors observed in experiments and quantitatively interpreted experimental observations in terms of the activities of different deformation mechanisms and the evolution of texture. It is found that the in-plane pre-tension has slight effect on the subsequent deformation, and the pre-compression and the reverse tension after compression have significant effect on the subsequent deformation. The inelastic behavior under compressive unloading is found to be insignificant at a small strain level but pronounced at a large strain level. Such significant effect is mainly ascribed to the activity of twinning and detwinning.

Cervical spondylosis: a rare and curable cause of vertebrobasilar insufficiency.

PubMed

Denis, Daniel J; Shedid, Daniel; Shehadeh, Mohammad; Weil, Alexander G; Lanthier, Sylvain

2014-05-01

Spondylotic vertebral artery (VA) compression is a rare cause of vertebrobasilar insufficiency and stroke. A 53-year-old man experienced multiple brief vertebrobasilar transient ischemic attacks (TIAs) and strokes, not apparently triggered by neck movements. Brain magnetic resonance imaging (MRI) documented consecutive infarcts, first in the left then right medial posterior inferior cerebellar artery (PICA) territories. Angiography showed two extracranial right vertebral artery (VA) stenoses, left VA hypoplasia, absence of left PICA and a dominant right PICA. Computed tomography angiography revealed right VA compression by osteophytes at C5-C6 and C6-C7 levels. No further vertebrobasilar insufficiency symptoms occurred in the 65 months following VA surgical decompression. Our literature review found 49 published surgical cases with vertebrobasilar symptoms caused by cervical spondylosis. Forty cases had one or more brief TIAs frequently triggered by neck movements. Three cases presented with stroke without prior TIA, with symptoms suggesting a top of the basilar artery embolic infarcts (one combined with a PICA infarct). Six cases had both TIAs and minor stroke. VA compression by uncovertebral osteophytes at the C5-C6 level was common. Dynamic angiography done in 38 cases systematically revealed worsening of VA stenosis or complete occlusion with either neck extension or rotation (ipsilateral when specified). Contralateral VA incompetence was found in 14 patients. Spondylotic VA stenosis can cause hemodynamic TIAs and watershed strokes, especially when contralateral VA insufficiency is combined to specific neck movements. Low-amplitude neck movement may suffice in severe cases. Embolic vertebrobasilar events are less frequent. VA decompression from spondylosis may prevent recurrent ischemic episodes.

Surgical treatment of congenital thoracolumbar spondyloptosis in a 2-year-old child with vertebral column resection and posterior-only circumferential reconstruction of the spine column: case report.

PubMed

Gressot, Loyola V; Mata, Javier A; Luerssen, Thomas G; Jea, Andrew

2015-02-01

Spondyloptosis refers to complete dislocation of a vertebral body onto another. The L5-S1 level is frequently affected. As this condition is rare, few published reports describing its clinical features and surgical outcomes exist, especially in the pediatric patient population. The authors report the presentation, pathological findings, and radiographic studies of a 2-year-old girl who presented to Texas Children's Hospital with a history since birth of progressive spastic paraparesis. Preoperative CT and MRI showed severe spinal cord compression associated with T11-12 spondyloptosis. The patient underwent a single-stage posterior approach for complete resection of the dysplastic vertebral bodies at the apex of the spinal deformity with reconstruction and stabilization of the vertebral column using a titanium expandable cage and pedicle screws. At the 12-month follow-up, the patient remained neurologically stable without any radiographic evidence of instrumentation failure or loss of alignment. To the best of the authors' knowledge, there have been only 2 other children with congenital thoracolumbar spondyloptosis treated with the above-described strategy. The authors describe their case and review the literature to discuss the aggregate clinical features, surgical strategies, and operative outcomes for congenital thoracolumbar spondyloptosis.

Pure Spinal Epidural Cavernous Hemangioma with Intralesional Hemorrhage: A Rare Cause of Thoracic Myelopathy

PubMed Central

Jang, Donghwan; Kim, Choonghyo; Lee, Seung Jin; Ryu, Young-Joon

2014-01-01

Although cavernous hemangiomas occur frequently in the intracranial structures, they are rare in the spine. Most of spinal hemangiomas are vertebral origin and "pure" epidural hemangiomas not originating from the vertebral bone are very rare. Our spinal hemangioma case is extremely rare because of its "pure" epidural involvement and intralesional hemorrhage. A 64-year-old man presented with progressive paraparesis from two months ago. His motor weakness was rated as grade 4/5 in bilateral lower extremities. He also complained of decreased sensation below the T4 sensory dermatome, which continuously progressed to the higher dermatome level. Magnetic resonance imaging demonstrated thoracic spinal tumor at T3-T4 level. The tumor was located epidural space compressing thoracic spinal cord ventrally. The tumor was not involved with the thoracic vertebral bone. We performed T3-5 laminectomy and removed the tumor completely. The tumor was not infiltrating into intradural space or vertebral bone. The histopathologic study confirmed the epidural tumor as cavernous hemangioma. Postoperatively, his weakness improved gradually. Four months later, his paraparesis recovered completely. Here, we present a case of pure spinal epidural cavernous hemangioma, which has intralesional hemorrhage. We believe cavernous hemangioma should be included in the differential diagnosis of the spinal epidural tumors. PMID:25110490

Long term outcome of treatment of vertebral body hemangiomas with direct ethanol injection and short segment stabilization.

PubMed

Chandra, P Sarat; Singh, Pankaj; K, Rajender; Agarwal, Deepak; Tandon, Vivek; Kale, S S; Sarkar, Chitra

2018-06-08

Vertebral body (VH) hemangiomas with myelopathy are difficult to manage. To evaluate the role of intra-operative ethanol embolization, surgical decompression and instrumented short segment fusion in VH with myelopathy and long-term outcome (>24 months). Prospective study: Symptomatic VH with cord compression with myelopathy. Excluded: pathological fractures, and/or deformity or multi-level pathologies. Surgery consisted of intra-operative bilateral pedicular absolute alcohol (<1% hydrated ethyl alcohol) injection, laminectomy and cord decompression at the level of pathology followed by a short segment instrumented fusion using pedicle screws. 33 patients (Mean 26.9 + 13.2, range: 10-68 years, 18 females). myelopathy all (5 paraplegic), sphincter involvement (13), and mid back/ lower pain (7). Pre-operative American Spinal Injury Association (ASIA) scores: A(7), B(11), C(6), D(8) and E(1). Majority had single vertebral involvement (30), 3 multiple level. Six underwent surgery earlier (1 alcohol embolization here). Mean surgical time: 124+39 minutes, average blood: 274+80 cc. Mean amount of absolute alcohol injected: 14.6+5.7 cc. (2 requiring 20 & 25 cc). Immediate embolization achieved in all, allowing laminectomy and soft-tissue hemangioma removal easily. Post-surgery, 1 patient had transient deterioration, rest all patients improved (sphincters improved in 9) at a follow up ranging 28-103 months (mean 47.6+22.3). Follow-up ASIA scores: E(26), D(4), B(2) & C(1). All patients showed evidence of bone sclerosis and relief of cord compression on follow-up imaging. This is largest study in literature showing excellent improvement, low re-operation rates following ethanol embolization and short segment fixation. Copyright © 2018. Published by Elsevier Inc.

[Cement augmentation on the spine : Biomechanical considerations].

PubMed

Kolb, J P; Weiser, L; Kueny, R A; Huber, G; Rueger, J M; Lehmann, W

2015-09-01

Vertebral compression fractures are the most common osteoporotic fractures. Since the introduction of vertebroplasty and screw augmentation, the management of osteoporotic fractures has changed significantly. The biomechanical characteristics of the risk of adjacent fractures and novel treatment modalities for osteoporotic vertebral fractures, including pure cement augmentation by vertebroplasty, and cement augmentation of screws for posterior instrumentation, are explored. Eighteen human osteoporotic lumbar spines (L1-5) adjacent to vertebral bodies after vertebroplasty were tested in a servo-hydraulic machine. As augmentation compounds we used standard cement and a modified low-strength cement. Different anchoring pedicle screws were tested with and without cement augmentation in another cohort of human specimens with a simple pull-out test and a fatigue test that better reflects physiological conditions. Cement augmentation in the osteoporotic spine leads to greater biomechanical stability. However, change in vertebral stiffness resulted in alterations with the risk of adjacent fractures. By using a less firm cement compound, the risk of adjacent fractures is significantly reduced. Both screw augmentation techniques resulted in a significant increase in the withdrawal force compared with the group without cement. Augmentation using perforated screws showed the highest stability in the fatigue test. The augmentation of cement leads to a significant change in the biomechanical properties. Differences in the stability of adjacent vertebral bodies increase the risk of adjacent fractures, which could be mitigated by a modified cement compound with reduced strength. Screws that were specifically designed for cement application displayed greatest stability in the fatigue test.

Acute hind limb paralysis secondary to an extradural spinal cord Cryptococcus gattii lesion in a dog

PubMed Central

Kurach, Lindsey; Wojnarowicz, Chris; Wilkinson, Tom; Sereda, Colin

2013-01-01

A 2-year-old, spayed female, German short-haired pointer was presented with a 1-day history of non-ambulatory paraplegia with absent deep pain perception. A computed tomography scan revealed an irregular eighth thoracic vertebral body and an extradural compressive lesion. Decompression was performed and abnormal tissues were submitted for analysis. Findings were consistent with a Cryptococcus gattii infection. PMID:24155428

The Vestibular Apparatus under Water and in Compressed Gas Environments: Abstracts of Translated Studies

DTIC Science & Technology

1975-02-01

found no evidence for progressive degeneration of the neurological symptoms, although there was no recovery either. 13. LANGE, J., I. ROZSAHEGYI...des Gehoemerven in den Maculae und Cristae Acustlcae Im Gehoerlabyrinth der Wirbeltiere. (The manner of termina- tion of the auditory nerve in the... maculae and cristae acustlcae in the auditory labyrinth of vertebrates. Trans, by Mrs. A. Woke, NMRI, 1972.) Biologische Untersuchungen (Stockholm

An ultrasonic measurement for in vitro depth-dependent equilibrium strains of articular cartilage in compression

NASA Astrophysics Data System (ADS)

Zheng, Y. P.; Mak, A. F. T.; Lau, K. P.; Qin, L.

2002-09-01

The equilibrium depth-dependent biomechanical properties of articular cartilage were measured using an ultrasound-compression method. Ten cylindrical bovine patella cartilage-bone specimens were tested in compression followed by a period of force-relaxation. A 50 MHz focused ultrasound beam was transmitted into the cartilage specimen through a remaining bone layer and a small hole at the centre of a specimen platform. The ultrasound echoes reflected or scattered within the articular cartilage were collected using the same transducer. The displacements of the tissues at different depths of the articular cartilage were derived from the ultrasound echo signals recorded during the compression and the subsequent force-relaxation. For two steps of 0.1 mm compression, the average strain at the superficial 0.2 mm thick layer (0.35 +/- 0.09) was significantly (p < 0.05) larger than that at the subsequent 0.2 mm thick layer (0.05 +/- 0.07) and that at deeper layers (0.01 +/- 0.02). It was demonstrated that the compressive biomechanical properties of cartilage were highly depth-dependent. The results suggested that the ultrasound-compression method could be a useful tool for the study of the depth-dependent biomechanical properties of articular cartilage.

Clinical outcome after the use of a new craniocaudal expandable implant for vertebral compression fracture treatment: one year results from a prospective multicentric study.

PubMed

Noriega, David; Krüger, Antonio; Ardura, Francisco; Hansen-Algenstaedt, Nils; Hassel, Frank; Barreau, Xavier; Beyerlein, Jörg

2015-01-01

The purpose of this prospective multicentric observational study was to confirm the safety and clinical performance of a craniocaudal expandable implant used in combination with high viscosity PMMA bone cement for the treatment of vertebral compression fractures. Thirty-nine VCFs in 32 patients were treated using the SpineJack minimally invasive surgery protocol. Outcome was determined by using the Visual Analogue Scale for measuring pain, the Oswestry Disability Index for scoring functional capacity, and the self-reporting European Quality of Life scores for the quality of life. Safety was evaluated by reporting all adverse events. The occurrence of cement leakages was assessed by either radiographs or CT scan or both. Statistically significant improvements were found regarding pain, function, and quality of life. The global pain score reduction at 1 year was 80.9% compared to the preoperative situation and the result of the Oswestry Disability Index showed a decrease from 65.0% at baseline to 10.5% at 12 months postoperatively. The cement leakage rate was 30.8%. No device- or surgery-related complications were found. This observational study demonstrates promising and persistent results consisting of immediate and sustained pain relief and durable clinical improvement after the procedure and throughout the 1-year follow-up period.

Anterior Transposition of Anomalous Tortuous Vertebral Artery Causing Cervical Radiculopathy: A Report of 2 Cases and Review of Literature.

PubMed

Wang, Doris D; Burkhardt, Jan-Karl; Magill, Stephen T; Lawton, Michael T

2017-05-01

Cervical radiculopathy secondary to compression from vertebral artery (VA) tortuosity is a rare entity. We describe successful transposition through an anterolateral approach of tortuous VA loops causing cervical radiculopathy. Two patients with cervical radiculopathy (first case at C5-6 and second case at C3-4) secondary to anomalous VA loop compression underwent anterolateral approaches to the cervical spine for decompression and VA transposition. The anterior transverse foramina were drilled to unroof the VA loop, which was dissected free from the exiting nerve root. In both cases, the affected cervical nerve root was successfully decompressed with both radiographic and clinical improvements in radiculopathy symptoms. We found 8 other cases of VA transposition via either an anterolateral approach or a posterolateral approach described in the literature. Our second case of anterolateral VA transposition at the C3-4 level is the first case at this level and the highest level reported in the literature. Decompression using an anterolateral approach with direct microvascular transposition of the VA is a safe and effective treatment of this pathology and addresses the cause of radiculopathy more directly than the posterolateral approach. Copyright © 2017 Elsevier Inc. All rights reserved.

Vertebral column deformities in white-beaked dolphins from the eastern North Atlantic.

PubMed

Bertulli, Chiara G; Galatius, Anders; Kinze, Carl C; Rasmussen, Marianne H; Deaville, Rob; Jepson, Paul; Vedder, Elisabeth J; Sánchez Contreras, Guillermo J; Sabin, Richard C; Watson, Alastair

2015-09-17

Five white-beaked dolphins Lagenorhynchus albirostris with outwardly vertebral kyphosis, kyphoscoliosis or lordosis were identified during a photo-identification survey of over 400 individuals (2002-2013) in Faxaflói and Skjálfandi Bays, Iceland. In addition, 3 stranding reports from Denmark, The Netherlands and the UK were analysed, providing both external observation and post mortem details of axial deviations of the vertebral column in this species. Two of the free-ranging cases and 2 of the stranded specimens appeared to have an acquired disease, either as a direct result of trauma, or indirectly from trauma/wound and subsequent infection and bony proliferation, although we were unable to specifically identify the causes. Our data represent a starting point to understand vertebral column deformations and their implications in white-beaked dolphins from the eastern North Atlantic. We recommend for future necropsy cases to conduct macro- and microscopic evaluation of muscle from both sides of the deformed region, in order to assess chronic or acute conditions related to the vertebral deformations and cause of death.

The Influence of GI and GII on the Compression After Impact Strength of Carbon Fiber/Epoxy Laminates and Sandwich Structure

NASA Technical Reports Server (NTRS)

Nettles, A. T.; Scharber, L. L.

2017-01-01

This study measured the compression after impact strength of IM7 carbon fiber laminates made from epoxy resins with various mode I and mode II toughness values to observe the effects of these toughness values on the resistance to damage formation and subsequent residual compression strength-carrying capabilities. Both monolithic laminates and sandwich structure were evaluated. A total of seven different epoxy resin systems were used ranging in approximate GI values of 245-665 J/sq m and approximate GII values of 840-2275 J/sq m. The results for resistance to impact damage formation showed that there was a direct correlation between GII and the planar size of damage, as measured by thermography. Subsequent residual compression strength testing suggested that GI had no influence on the measured values and most of the difference in compression strength was directly related to the size of damage. Thus, delamination growth assumed as an opening type of failure mechanism does not appear to be responsible for loss of compression strength in the specimens examined in this study.

Effect of pre-straining on the evolution of material anisotropy in rolled magnesium alloy AZ31 sheet

NASA Astrophysics Data System (ADS)

Qiao, H.; Guo, X. Q.; Wu, P. D.

2013-12-01

The large strain Elastic Visco-Plastic Self-Consistent (EVPSC) model and the recently developed Twinning and De-Twinning (TDT) model are applied to study the mechanical behavior of rolled magnesium alloy AZ31 sheet. Three different specimen orientations with tilt angles of 0°, 45° and 90° between the rolling direction and longitudinal specimen axis are used to study the mechanical anisotropy under both uniaxial tension and compression. The effect of pre-strain in uniaxial compression along the rolling direction on subsequent uniaxial tension/compression along the three directions is also investigated. It is demonstrated that the twinning during pre-strain in compression and the detwinning in the subsequent deformation have a significant influence on the mechanical anisotropy. Numerical results are in good agreement with the experimental observations found in the literature.

Analysis of the Factors Contributing to Vertebral Compression Fractures After Spine Stereotactic Radiosurgery

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

Boyce-Fappiano, David; Elibe, Erinma; Schultz, Lonni

Purpose: To determine our institutional vertebral compression fracture (VCF) rate after spine stereotactic radiosurgery (SRS) and determine contributory factors. Methods and Materials: Retrospective analysis from 2001 to 2013 at a single institution was performed. With institutional review board approval, electronic medical records of 1905 vertebral bodies from 791 patients who were treated with SRS for the management of primary or metastatic spinal lesions were reviewed. A total of 448 patients (1070 vertebral bodies) with adequate follow-up imaging studies available were analyzed. Doses ranging from 10 Gy in 1 fraction to 60 Gy in 5 fractions were delivered. Computed tomography and magnetic resonancemore » imaging were used to evaluate the primary endpoints of this study: development of a new VCF, progression of an existing VCF, and requirement of stabilization surgery after SRS. Results: A total of 127 VCFs (11.9%; 95% confidence interval [CI] 9.5%-14.2%) in 97 patients were potentially SRS induced: 46 (36%) were de novo, 44 (35%) VCFs progressed, and 37 (29%) required stabilization surgery after SRS. Our rate for radiologic VCF development/progression (excluding patients who underwent surgery) was 8.4%. Upon further exclusion of patients with hematologic malignancies the VCF rate was 7.6%. In the univariate analyses, females (hazard ratio [HR] 1.54, 95% CI 1.01-2.33, P=.04), prior VCF (HR 1.99, 95% CI 1.30-3.06, P=.001), primary hematologic malignancies (HR 2.68, 95% CI 1.68-4.28, P<.001), thoracic spine lesions (HR 1.46, 95% CI 1.02-2.10, P=.02), and lytic lesions had a significantly increased risk for VCF after SRS. On multivariate analyses, prior VCF and lesion type remained contributory. Conclusions: Single-fraction SRS doses of 16 to 18 Gy to the spine seem to be associated with a low rate of VCFs. To the best of our knowledge, this is the largest reported experience analyzing SRS-induced VCFs, with one of the lowest event rates reported.« less

KAST Study: The Kiva System As a Vertebral Augmentation Treatment-A Safety and Effectiveness Trial: A Randomized, Noninferiority Trial Comparing the Kiva System With Balloon Kyphoplasty in Treatment of Osteoporotic Vertebral Compression Fractures.

PubMed

Tutton, Sean M; Pflugmacher, Robert; Davidian, Mark; Beall, Douglas P; Facchini, Francis R; Garfin, Steven R

2015-06-15

The KAST (Kiva Safety and Effectiveness Trial) study was a pivotal, multicenter, randomized control trial for evaluation of safety and effectiveness in the treatment of patients with painful, osteoporotic vertebral compression fractures (VCFs). The objective was to demonstrate noninferiority of the Kiva system to balloon kyphoplasty (BK) with respect to the composite primary endpoint. Annual incidence of osteoporotic VCFs is prevalent. Optimal treatment of VCFs should address pain, function, and deformity. Kiva is a novel implant for vertebral augmentation in the treatment of VCFs. A total of 300 subjects with 1 or 2 painful osteoporotic VCFs were randomized to blindly receive Kiva (n = 153) or BK (n = 147). Subjects were followed through 12 months. The primary endpoint was a composite at 12 months defined as a reduction in fracture pain by at least 15 mm on the visual analogue scale, maintenance or improvement in function on the Oswestry Disability Index, and absence of device-related serious adverse events. Secondary endpoints included cement usage, extravasation, and adjacent level fracture. A mean improvement of 70.8 and 71.8 points in the visual analogue scale score and 38.1 and 42.2 points in the Oswestry Disability Index was noted in Kiva and BK, respectively. No device-related serious adverse events occurred. Despite significant differences in risk factors favoring the control group at baseline, the primary endpoint demonstrated noninferiority of Kiva to BK. Analysis of secondary endpoints revealed superiority with respect to cement use and site-reported extravasation and a positive trend in adjacent level fracture warranting further study. The KAST study successfully established that the Kiva system is noninferior to BK based on a composite primary endpoint assessment incorporating pain-, function-, and device-related serious adverse events for the treatment of VCFs due to osteoporosis. Kiva was shown to be noninferior to BK and revealed a positive trend in several secondary endpoints. 1.

Economic Analysis of Kiva VCF Treatment System Compared to Balloon Kyphoplasty Using Randomized Kiva Safety and Effectiveness Trial (KAST) Data.

PubMed

Beall, Douglas P; Olan, Wayne J; Kakad, Priyanka; Li, Qianyi; Hornberger, John

2015-01-01

Vertebral compression fractures (VCFs) are the most common osteoporotic fractures and cause persistent pain, kyphotic deformity, weight loss, depression, reduced quality of life, and even death. Current surgical approaches for the treatment of VCF include vertebroplasty (VP) and balloon kyphoplasty (BK). The Kiva® VCF Treatment System (Kiva System) is a next-generation alternative surgical intervention in which a percutaneously introduced nitinol Osteo Coil guidewire is advanced through a deployment cannula and subsequently a PEEK Implant is implanted incrementally and fully coiled in the vertebral body. The Kiva System's effectiveness for the treatment of VCF has been evaluated in a large randomized controlled trial, the Kiva Safety and Effectiveness Trial (KAST). The Kiva System was non-inferior to BK with respect to pain reduction (70.8% vs. 71.8% in Visual Analogue Scale) and physical function restoration (38.1 % vs. 42.2% reduction in Oswestry Disability Index) while using less bone cement. The economic impact of the Kiva system has yet to be analyzed. To analyze hospital resource use and costs of the Kiva System over 2 years for the treatment of VCF compared to BK. A representative US hospital. Economic analysis of the KAST randomized trial, focusing on hospital resource use and costs. The analysis was conducted from a hospital perspective and utilized clinical data from KAST as well as unit-cost data from the published literature. The cost of initial VCF surgery, reoperation cost, device market cost, and other medical costs were compared between the Kiva System and BK. The relative risk reduction rate in adjacent-level fracture with Kiva [31.6% (95% CI: -22.5%, 61.9%)] demonstrated in KAST was used in this analysis. With 304 vertebral augmentation procedures performed in a representative U.S. hospital over 2 years, the Kiva System will produce a direct medical cost savings of $1,118 per patient and $280,876 per hospital. This cost saving with the Kiva System was attributable to 19 reduced adjacent-level fractures with the Kiva System. This study does not compare the Kiva System with VP or any other non-surgical procedures for the treatment of VCF. This first-ever economic analysis of the KAST data showed that the Kiva System for vertebral augmentation is hospital resource and cost saving over BK in a hospital setting over 2 years. These savings are attributable to reduced risk of developing adjacent-level fractures with the Kiva System compared to BK.

Prevalence of Poor Bone Quality in Women Undergoing Spinal Fusion Using Biomechanical-CT Analysis.

PubMed

Burch, Shane; Feldstein, Michael; Hoffmann, Paul F; Keaveny, Tony M

2016-02-01

Retrospective, cross-sectional analysis of vertebral bone quality in spine-fusion patients at a single medical center. To characterize the prevalence of osteoporosis and fragile bone strength in a spine-fusion population of women with an age range of 50 years to 70 years. Fragile bone strength is defined as the level of vertebral strength below which a patient is at as high a risk of future vertebral fracture as a patient having bone density-defined osteoporosis. Poor bone quality--defined here as the presence of either osteoporosis or fragile bone strength--is a risk factor for spine-fusion patients that often goes undetected but can now be assessed preoperatively by additional postprocessing of computed tomography (CT) scans originally ordered for perioperative clinical assessment. Utilizing such perioperative CT scans for a cohort of 98 women (age range: 51-70 yr) about to undergo spine fusion, we retrospectively used a phantomless calibration technique and biomechanical-CT postprocessing analysis to measure vertebral trabecular bone mineral density (BMD) (in mg/cm³) and by nonlinear finite element analysis, vertebral compressive strength (in Newtons, N) in the L1 or L2 vertebra. Preestablished validated threshold values were used to define the presence of osteoporosis (trabecular BMD of 80 mg/cm³ or lower) and fragile bone strength (vertebral strength of 4500 N or lower). Fourteen percent of the women tested positive for osteoporosis, 27% tested positive for fragile bone strength, and 29% were classified as having poor bone quality (either osteoporosis or fragile bone strength). Over this narrow age range, neither BMD nor vertebral strength were significantly correlated with age, weight, height, or body mass index (P values 0.14-0.97 for BMD; 0.13-0.51 for strength). Poor bone quality appears to be common in women between ages 50 years and 70 years undergoing spinal fusion surgery. 3.

Evolution of the shut-off steps of vertebrate phototransduction

PubMed Central

Patel, Hardip R.; Chuah, Aaron

2018-01-01

Different isoforms of the genes involved in phototransduction are expressed in vertebrate rod and cone photoreceptors, providing a unique example of parallel evolution via gene duplication. In this study, we determine the molecular phylogeny of the proteins underlying the shut-off steps of phototransduction in the agnathan and jawed vertebrate lineages. For the G-protein receptor kinases (GRKs), the GRK1 and GRK7 divisions arose prior to the divergence of tunicates, with further expansion during the two rounds of whole-genome duplication (2R); subsequently, jawed and agnathan vertebrates retained different subsets of three isoforms of GRK. For the arrestins, gene expansion occurred during 2R. Importantly, both for GRKs and arrestins, the respective rod isoforms did not emerge until the second round of 2R, just prior to the separation of jawed and agnathan vertebrates. For the triplet of proteins mediating shut-off of the G-protein transducin, RGS9 diverged from RGS11, probably at the second round of 2R, whereas Gβ5 and R9AP appear not to have undergone 2R expansion. Overall, our analysis provides a description of the duplications and losses of phototransduction shut-off genes that occurred during the transition from a chordate with only cone-like photoreceptors to an ancestral vertebrate with both cone- and rod-like photoreceptors. PMID:29321241

International Myeloma Working Group Recommendations for the Treatment of Multiple Myeloma–Related Bone Disease

PubMed Central

Terpos, Evangelos; Morgan, Gareth; Dimopoulos, Meletios A.; Drake, Matthew T.; Lentzsch, Suzanne; Raje, Noopur; Sezer, Orhan; García-Sanz, Ramón; Shimizu, Kazuyuki; Turesson, Ingemar; Reiman, Tony; Jurczyszyn, Artur; Merlini, Giampaolo; Spencer, Andrew; Leleu, Xavier; Cavo, Michele; Munshi, Nikhil; Rajkumar, S. Vincent; Durie, Brian G.M.; Roodman, G. David

2013-01-01

Purpose The aim of the International Myeloma Working Group was to develop practice recommendations for the management of multiple myeloma (MM) –related bone disease. Methodology An interdisciplinary panel of clinical experts on MM and myeloma bone disease developed recommendations based on published data through August 2012. Expert consensus was used to propose additional recommendations in situations where there were insufficient published data. Levels of evidence and grades of recommendations were assigned and approved by panel members. Recommendations Bisphosphonates (BPs) should be considered in all patients with MM receiving first-line antimyeloma therapy, regardless of presence of osteolytic bone lesions on conventional radiography. However, it is unknown if BPs offer any advantage in patients with no bone disease assessed by magnetic resonance imaging or positron emission tomography/computed tomography. Intravenous (IV) zoledronic acid (ZOL) or pamidronate (PAM) is recommended for preventing skeletal-related events in patients with MM. ZOL is preferred over oral clodronate in newly diagnosed patients with MM because of its potential antimyeloma effects and survival benefits. BPs should be administered every 3 to 4 weeks IV during initial therapy. ZOL or PAM should be continued in patients with active disease and should be resumed after disease relapse, if discontinued in patients achieving complete or very good partial response. BPs are well tolerated, but preventive strategies must be instituted to avoid renal toxicity or osteonecrosis of the jaw. Kyphoplasty should be considered for symptomatic vertebral compression fractures. Low-dose radiation therapy can be used for palliation of uncontrolled pain, impending pathologic fracture, or spinal cord compression. Orthopedic consultation should be sought for long-bone fractures, spinal cord compression, and vertebral column instability. PMID:23690408

Effect of tensile twins on the subsequent plastic deformation in rolled Mg-3Al-1Zn alloy

NASA Astrophysics Data System (ADS)

Yoon, Jonghun; Kim, Se-Jong; Lee, Youngseon

2013-12-01

The {101¯2} tensile twins influence plastic flow of magnesium alloys for the subsequent plastic deformation since it contributes to grain refinement and texture hardening between the twinned and untwined regions. This paper investigates the variation of plastic flow of the rolled Mg-3Al-1Zn alloy which is compressed with a small plastic strain at the room temperature to induce the twins in the initial specimen. Subsequent tension and compression along the rolling and transverse direction are conducted with the twin induced specimens in order to examine the effect of the initial tensile twins.

Phase I/II Trial of Epothilone Analog BMS-247550, Mitoxantrone, and Prednisone in HRPC Patients Previously Treated with Chemotherapy

DTIC Science & Technology

2006-07-01

McGaw AccuPro Pump Nitroglycerine IV Set (Catalog #V8333) • Clintec IV Fat Emulsion Set (Catalog #2C1105) Filter extension set (to be used with IV sets...menses; libido; vaginitis Vascular – thrombosis/ embolism ; vascular access complication Note: BMS-247550 in combination with other agents could cause...osteoporosis, vertebral compression fractures , pancreatitis, esophagitis, peptic ulcer, dermatologic disturbances, convulsions, vertigo, headache

Neurons selective to the number of visual items in the corvid songbird endbrain

PubMed Central

Ditz, Helen M.; Nieder, Andreas

2015-01-01

It is unknown whether anatomical specializations in the endbrains of different vertebrates determine the neuronal code to represent numerical quantity. Therefore, we recorded single-neuron activity from the endbrain of crows trained to judge the number of items in displays. Many neurons were tuned for numerosities irrespective of the physical appearance of the items, and their activity correlated with performance outcome. Comparison of both behavioral and neuronal representations of numerosity revealed that the data are best described by a logarithmically compressed scaling of numerical information, as postulated by the Weber–Fechner law. The behavioral and neuronal numerosity representations in the crow reflect surprisingly well those found in the primate association cortex. This finding suggests that distantly related vertebrates with independently developed endbrains adopted similar neuronal solutions to process quantity. PMID:26056278

[The kinological identification of individual scents in the traces of the vital activities of 4 vertebrate species].

PubMed

Sokolov, V E; Sulimov, K T; Krutova, V I

1990-01-01

One can successfully identify individual odors of almost any terrestrial vertebrates using laboratory dogs. The excretions can be collected on adsorbent paper and conserved for subsequent identification. It has been experimentally shown that the odor of house mice remains stable during the whole life span and that the stabilization of dog-identifiable odors finishes in young mice at 14 day. The method tested will allow to create individual banks of animal odors, e.g. for identification of rare species.

Elemental Markers in Elasmobranchs: Effects of Environmental History and Growth on Vertebral Chemistry

PubMed Central

Smith, Wade D.; Miller, Jessica A.; Heppell, Selina S.

2013-01-01

Differences in the chemical composition of calcified skeletal structures (e.g. shells, otoliths) have proven useful for reconstructing the environmental history of many marine species. However, the extent to which ambient environmental conditions can be inferred from the elemental signatures within the vertebrae of elasmobranchs (sharks, skates, rays) has not been evaluated. To assess the relationship between water and vertebral elemental composition, we conducted two laboratory studies using round stingrays, Urobatis halleri, as a model species. First, we examined the effects of temperature (16°, 18°, 24°C) on vertebral elemental incorporation (Li/Ca, Mg/Ca, Mn/Ca, Zn/Ca, Sr/Ca, Ba/Ca). Second, we tested the relationship between water and subsequent vertebral elemental composition by manipulating dissolved barium concentrations (1x, 3x, 6x). We also evaluated the influence of natural variation in growth rate on elemental incorporation for both experiments. Finally, we examined the accuracy of classifying individuals to known environmental histories (temperature and barium treatments) using vertebral elemental composition. Temperature had strong, negative effects on the uptake of magnesium (DMg) and barium (DBa) and positively influenced manganese (DMn) incorporation. Temperature-dependent responses were not observed for lithium and strontium. Vertebral Ba/Ca was positively correlated with ambient Ba/Ca. Partition coefficients (DBa) revealed increased discrimination of barium in response to increased dissolved barium concentrations. There were no significant relationships between elemental incorporation and somatic growth or vertebral precipitation rates for any elements except Zn. Relationships between somatic growth rate and DZn were, however, inconsistent and inconclusive. Variation in the vertebral elemental signatures of U. halleri reliably distinguished individual rays from each treatment based on temperature (85%) and Ba exposure (96%) history. These results support the assumption that vertebral elemental composition reflects the environmental conditions during deposition and validates the use of vertebral elemental signatures as natural markers in an elasmobranch. Vertebral elemental analysis is a promising tool for the study of elasmobranch population structure, movement, and habitat use. PMID:24098320

Elemental markers in elasmobranchs: effects of environmental history and growth on vertebral chemistry.

PubMed

Smith, Wade D; Miller, Jessica A; Heppell, Selina S

2013-01-01

Differences in the chemical composition of calcified skeletal structures (e.g. shells, otoliths) have proven useful for reconstructing the environmental history of many marine species. However, the extent to which ambient environmental conditions can be inferred from the elemental signatures within the vertebrae of elasmobranchs (sharks, skates, rays) has not been evaluated. To assess the relationship between water and vertebral elemental composition, we conducted two laboratory studies using round stingrays, Urobatis halleri, as a model species. First, we examined the effects of temperature (16°, 18°, 24°C) on vertebral elemental incorporation (Li/Ca, Mg/Ca, Mn/Ca, Zn/Ca, Sr/Ca, Ba/Ca). Second, we tested the relationship between water and subsequent vertebral elemental composition by manipulating dissolved barium concentrations (1x, 3x, 6x). We also evaluated the influence of natural variation in growth rate on elemental incorporation for both experiments. Finally, we examined the accuracy of classifying individuals to known environmental histories (temperature and barium treatments) using vertebral elemental composition. Temperature had strong, negative effects on the uptake of magnesium (DMg) and barium (DBa) and positively influenced manganese (DMn) incorporation. Temperature-dependent responses were not observed for lithium and strontium. Vertebral Ba/Ca was positively correlated with ambient Ba/Ca. Partition coefficients (DBa) revealed increased discrimination of barium in response to increased dissolved barium concentrations. There were no significant relationships between elemental incorporation and somatic growth or vertebral precipitation rates for any elements except Zn. Relationships between somatic growth rate and DZn were, however, inconsistent and inconclusive. Variation in the vertebral elemental signatures of U. halleri reliably distinguished individual rays from each treatment based on temperature (85%) and Ba exposure (96%) history. These results support the assumption that vertebral elemental composition reflects the environmental conditions during deposition and validates the use of vertebral elemental signatures as natural markers in an elasmobranch. Vertebral elemental analysis is a promising tool for the study of elasmobranch population structure, movement, and habitat use.

Curative effect and mechanism of radiofrequency ablation nucleoplasty in the treatment of cervical vertigo.

PubMed

Yin, Hai-Dong; Zhang, Xin-Mei; Huang, Ming-Guang; Chen, Wei; Song, Yang; Du, Qing-Jun; Wu, Yu-Ning; Yang, Ruo-Bin

2017-04-01

This study aims to investigate the curative effects and mechanism of radiofrequency ablation nucleoplasty in the treatment of cervical vertigo. A total of 27 patients diagnosed with cervical vertigo from January 2012 to October 2014 received treatment of radiofrequency ablation nucleoplasty. The narrow-side vertebral artery diameters were examined by using Philips 1.5-T body dual-gradient MRI system. The haemodynamic parameters were detected by using transcranial Doppler sonography. Both of the vertebral artery diameters and haemodynamic parameters were recorded and compared before and after treatment. The curative effects in early post-operative application were evaluated according to the Nagashima standards. Radiofrequency ablation nucleoplasty was performed in a total of 59 cervical discs in 27 patients. The average operation time was 42.7 min, and the symptoms of 92.6% patients were alleviated after radiofrequency ablation nucleoplasty post-operation application. There was no significant difference in the narrow-side vertebral artery diameters before and after treatment in both Group A (p = 0.12) and Group B (p = 0.48); however, the blood flow velocity was significantly higher than that before treatment in both Group A (p = 0.01) and Group B (p = 0.03), respectively. Radiofrequency ablation nucleoplasty improves the blood flow in the narrow-side vertebral artery and illustrates the therapeutic effect on cervical vertigo in patients who have no direct compression of the vertebral artery. Advances in knowledge: Radiofrequency intradiscal nucleoplasty can be used as a minimally invasive procedure for treating cervical vertigo.

Relationships among diet, physical activity, and dual plane dual-energy X-ray absorptiometry bone outcomes in pre-pubertalgirls.

PubMed

Ren, Jie; Brann, Lynn S; Bruening, Kay S; Scerpella, Tamara A; Dowthwaite, Jodi N

2017-12-01

In pre-pubertal girls, nutrient intakes and non-aquatic organized activity were evaluated as factors in vertebral body bone mass, structure, and strength. Activity, vitamin B 12 , and dietary fiber predicted bone outcomes most consistently. Exercise and vitamin B 12 appear beneficial, whereas high fiber intake appears to be adverse for vertebral body development. Childhood development sets the baseline for adult fracture risk. Most studies evaluate development using postero-anterior (PA) dual-energy X-ray absorptiometry (DXA) areal bone mineral density, bone mineral content, and bone mineral apparent density. In a prior analysis, we demonstrated that PA DXA reflects posterior element properties, rather than vertebral body fracture sites, such that loading is associated with subtle differences in vertebral body geometry, not 3D density. The current analysis is restricted to pre-pubertal girls, for a focused exploration of key nutrient intakes and physical activity as factors in dual plane indices of vertebral body geometry, density, and strength. This cross-sectional analysis used paired PA and supine lateral (LAT) lumbar spine DXA scans to assess "3D" vertebral body bone mineral apparent density (PALATBMAD), "3D" index of structural strength in axial compression (PALATIBS), and fracture risk index (PALATFRI). Diet data were collected using the Youth/Adolescent Questionnaire (YAQ, 1995); organized physical activity was recorded via calendar-based form. Pearson correlations and backward stepwise multiple linear regression analyzed associations among key nutrients, physical activity, and bone outcomes. After accounting for activity and key covariates, fiber, unsupplemented vitamin B 12 , zinc, carbohydrate, vitamin C, unsupplemented magnesium, and unsupplemented calcium intake explained significant variance for one or more bone outcomes (p < 0.05). After adjustment for influential key nutrients and covariates, activity exposure was associated with postero-anterior (PA) areal bone mineral density, PA bone mineral content, PA width, lateral (LAT) BMC, "3D" bone cross-sectional area (coronal plane), "3D" PALATIBS, and PALATFRI benefits (p < 0.05). Physical activity, fiber intake, and unsupplemented B 12 intake appear to influence vertebral body bone mass, density, geometry, and strength in well-nourished pre-pubertal girls; high fiber intakes may adversely affect childhood vertebral body growth.

Coccidian parasites of fish encompass profound phylogenetic diversity and gave rise to each of the major parasitic groups in terrestrial vertebrates.

PubMed

Rosenthal, Benjamin M; Dunams-Morel, Detiger; Ostoros, Gyorgyi; Molnár, Kálmán

2016-06-01

Fish are the oldest and most diverse group of vertebrates; it therefore stands to reason that fish may have been the original hosts for many types of extant vertebrate parasites. Here, we sought to determine whether coccidian parasites of fish are especially diverse. We therefore sampled such parasites from thirty-nine species of fish and tested phylogenetic hypotheses concerning their relationships, using 18S rDNA. We found compelling phylogenetic support for distinctions among at least four lineages of piscine parasites presently ascribed to the genus Goussia. Some, but not all parasites attributed to Eimeria were confirmed as such. Major taxonomic revisions are likely justified for these parasites of fish, which appear to have given rise to each of the major lineages of coccidian parasites that subsequently proliferated in terrestrial vertebrates, including those such as Toxoplasma gondii that form tissue cysts in intermediate hosts. Published by Elsevier B.V.

Predicting the mosquito species and vertebrate species involved in the theoretical transmission of Rift Valley fever virus in the United States.

PubMed

Golnar, Andrew J; Turell, Michael J; LaBeaud, A Desiree; Kading, Rebekah C; Hamer, Gabriel L

2014-09-01

Rift Valley fever virus (RVFV) is a mosquito-borne virus in the family Bunyaviridiae that has spread throughout continental Africa to Madagascar and the Arabian Peninsula. The establishment of RVFV in North America would have serious consequences for human and animal health in addition to a significant economic impact on the livestock industry. Published and unpublished data on RVFV vector competence, vertebrate host competence, and mosquito feeding patterns from the United States were combined to quantitatively implicate mosquito vectors and vertebrate hosts that may be important to RVFV transmission in the United States. A viremia-vector competence relationship based on published mosquito transmission studies was used to calculate a vertebrate host competence index which was then combined with mosquito blood feeding patterns to approximate the vector and vertebrate amplification fraction, defined as the relative contribution of the mosquito or vertebrate host to pathogen transmission. Results implicate several Aedes spp. mosquitoes and vertebrates in the order Artiodactyla as important hosts for RVFV transmission in the U.S. Moreover, this study identifies critical gaps in knowledge which would be necessary to complete a comprehensive analysis identifying the different contributions of mosquitoes and vertebrates to potential RVFV transmission in the U.S. Future research should focus on (1) the dose-dependent relationship between viremic exposure and the subsequent infectiousness of key mosquito species, (2) evaluation of vertebrate host competence for RVFV among North American mammal species, with particular emphasis on the order Artiodactyla, and (3) identification of areas with a high risk for RVFV introduction so data on local vector and host populations can help generate geographically appropriate amplification fraction estimates.

Predicting the Mosquito Species and Vertebrate Species Involved in the Theoretical Transmission of Rift Valley Fever Virus in the United States

PubMed Central

Golnar, Andrew J.; Turell, Michael J.; LaBeaud, A. Desiree; Kading, Rebekah C.; Hamer, Gabriel L.

2014-01-01

Rift Valley fever virus (RVFV) is a mosquito-borne virus in the family Bunyaviridiae that has spread throughout continental Africa to Madagascar and the Arabian Peninsula. The establishment of RVFV in North America would have serious consequences for human and animal health in addition to a significant economic impact on the livestock industry. Published and unpublished data on RVFV vector competence, vertebrate host competence, and mosquito feeding patterns from the United States were combined to quantitatively implicate mosquito vectors and vertebrate hosts that may be important to RVFV transmission in the United States. A viremia-vector competence relationship based on published mosquito transmission studies was used to calculate a vertebrate host competence index which was then combined with mosquito blood feeding patterns to approximate the vector and vertebrate amplification fraction, defined as the relative contribution of the mosquito or vertebrate host to pathogen transmission. Results implicate several Aedes spp. mosquitoes and vertebrates in the order Artiodactyla as important hosts for RVFV transmission in the U.S. Moreover, this study identifies critical gaps in knowledge which would be necessary to complete a comprehensive analysis identifying the different contributions of mosquitoes and vertebrates to potential RVFV transmission in the U.S. Future research should focus on (1) the dose-dependent relationship between viremic exposure and the subsequent infectiousness of key mosquito species, (2) evaluation of vertebrate host competence for RVFV among North American mammal species, with particular emphasis on the order Artiodactyla, and (3) identification of areas with a high risk for RVFV introduction so data on local vector and host populations can help generate geographically appropriate amplification fraction estimates. PMID:25211133

Report from the 2013 meeting of the International Compression Club on advances and challenges of compression therapy.

PubMed

Delos Reyes, Arthur P; Partsch, Hugo; Mosti, Giovanni; Obi, Andrea; Lurie, Fedor

2014-10-01

The International Compression Club, a collaboration of medical experts and industry representatives, was founded in 2005 to develop consensus reports and recommendations regarding the use of compression therapy in the treatment of acute and chronic vascular disease. During the recent meeting of the International Compression Club, member presentations were focused on the clinical application of intermittent pneumatic compression in different disease scenarios as well as on the use of inelastic and short stretch compression therapy. In addition, several new compression devices and systems were introduced by industry representatives. This article summarizes the presentations and subsequent discussions and provides a description of the new compression therapies presented. Copyright © 2014 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Posterior-only approach for lumbar vertebral column resection and expandable cage reconstruction for spinal metastases.

PubMed

Jandial, Rahul; Kelly, Brandon; Chen, Mike Yue

2013-07-01

The increasing incidence of spinal metastasis, a result of improved systemic therapies for cancer, has spurred a search for an alternative method for the surgical treatment of lumbar metastases. The authors report a single-stage posterior-only approach for resecting any pathological lumbar vertebral segment and reconstructing with a medium to large expandable cage while preserving all neurological structures. The authors conducted a retrospective consecutive case review of 11 patients (5 women, 6 men) with spinal metastases treated at 1 institution with single-stage posterior-only vertebral column resection and reconstruction with an expandable cage and pedicle screw fixation. For all patients, the indications for operative intervention were spinal cord compression, cauda equina compression, and/or spinal instability. Neurological status was classified according to the American Spinal Injury Association impairment scale, and functional outcomes were analyzed by using a visual analog scale for pain. For all patients, a circumferential vertebral column resection was achieved, and full decompression was performed with a posterior-only approach. Each cage was augmented by posterior pedicle screw fixation extending 2 levels above and below the resected level. No patient required a separate anterior procedure. Average estimated blood loss and duration of each surgery were 1618 ml (range 900-4000 ml) and 6.6 hours (range 4.5-9 hours), respectively. The mean follow-up time was 14 months (range 10-24 months). The median survival time after surgery was 17.7 months. Delayed hardware failure occurred for 1 patient. Preoperatively, 2 patients had intractable pain with intact lower-extremity strength and 8 patients had severe intractable pain, lower-extremity paresis, and were unable to walk; 4 of whom regained the ability to walk after surgery. Two patients who were paraplegic before decompression recovered substantial function but remained wheelchair bound, and 2 patients remained paraparetic after the surgery. No patients had lasting intraoperative neuromonitoring changes, and none died. Complications included 2 reoperations, 1 delayed hardware failure (cage subsidence that did not require revision), and 3 incidental durotomies (none of which required reoperation). No postoperative pneumonia, ileus, or deep venous thrombosis developed in any patient. A posterior-only approach for vertebral segment resection with preservation of spinal nerve roots is a viable technique that can be used throughout the entire lumbar spine. Extensive mobilization of the nerve roots is of utmost importance and allows for insertion and expansion of medium-sized, in situ expandable cages in the midline. This approach, although technically challenging, might reduce the morbidity associated with an anterior approach.

Notochord-dependent expression of MFH1 and PAX1 cooperates to maintain the proliferation of sclerotome cells during the vertebral column development.

PubMed

Furumoto, T A; Miura, N; Akasaka, T; Mizutani-Koseki, Y; Sudo, H; Fukuda, K; Maekawa, M; Yuasa, S; Fu, Y; Moriya, H; Taniguchi, M; Imai, K; Dahl, E; Balling, R; Pavlova, M; Gossler, A; Koseki, H

1999-06-01

During axial skeleton development, the notochord is essential for the induction of the sclerotome and for the subsequent differentiation of cartilage forming the vertebral bodies and intervertebral discs. These functions are mainly mediated by the diffusible signaling molecule Sonic hedgehog. The products of the paired-box-containing Pax1 and the mesenchyme forkhead-1 (Mfh1) genes are expressed in the developing sclerotome and are essential for the normal development of the vertebral column. Here, we demonstrate that Mfh1 like Pax1 expression is dependent on Sonic hedgehog signals from the notochord, and Mfh1 and Pax1 act synergistically to generate the vertebral column. In Mfh1/Pax1 double mutants, dorsomedial structures of the vertebrae are missing, resulting in extreme spina bifida accompanied by subcutaneous myelomeningocoele, and the vertebral bodies and intervertebral discs are missing. The morphological defects in Mfh1/Pax1 double mutants strongly correlate with the reduction of the mitotic rate of sclerotome cells. Thus, both the Mfh1 and the Pax1 gene products cooperate to mediate Sonic hedgehog-dependent proliferation of sclerotome cells. Copyright 1999 Academic Press.

Fingerprint recognition of wavelet-based compressed images by neuro-fuzzy clustering

NASA Astrophysics Data System (ADS)

Liu, Ti C.; Mitra, Sunanda

1996-06-01

Image compression plays a crucial role in many important and diverse applications requiring efficient storage and transmission. This work mainly focuses on a wavelet transform (WT) based compression of fingerprint images and the subsequent classification of the reconstructed images. The algorithm developed involves multiresolution wavelet decomposition, uniform scalar quantization, entropy and run- length encoder/decoder and K-means clustering of the invariant moments as fingerprint features. The performance of the WT-based compression algorithm has been compared with JPEG current image compression standard. Simulation results show that WT outperforms JPEG in high compression ratio region and the reconstructed fingerprint image yields proper classification.

The evolution of early vertebrate photoreceptors.

PubMed

Collin, Shaun P; Davies, Wayne L; Hart, Nathan S; Hunt, David M

2009-10-12

Meeting the challenge of sampling an ancient aquatic landscape by the early vertebrates was crucial to their survival and would establish a retinal bauplan to be used by all subsequent vertebrate descendents. Image-forming eyes were under tremendous selection pressure and the ability to identify suitable prey and detect potential predators was thought to be one of the major drivers of speciation in the Early Cambrian. Based on the fossil record, we know that hagfishes, lampreys, holocephalans, elasmobranchs and lungfishes occupy critical stages in vertebrate evolution, having remained relatively unchanged over hundreds of millions of years. Now using extant representatives of these 'living fossils', we are able to piece together the evolution of vertebrate photoreception. While photoreception in hagfishes appears to be based on light detection and controlling circadian rhythms, rather than image formation, the photoreceptors of lampreys fall into five distinct classes and represent a critical stage in the dichotomy of rods and cones. At least four types of retinal cones sample the visual environment in lampreys mediating photopic (and potentially colour) vision, a sampling strategy retained by lungfishes, some modern teleosts, reptiles and birds. Trichromacy is retained in cartilaginous fishes (at least in batoids and holocephalans), where it is predicted that true scotopic (dim light) vision evolved in the common ancestor of all living gnathostomes. The capacity to discriminate colour and balance the tradeoff between resolution and sensitivity in the early vertebrates was an important driver of eye evolution, where many of the ocular features evolved were retained as vertebrates progressed on to land.

Studies of a new multi-layer compression bandage for the treatment of venous ulceration.

PubMed

Scriven, J M; Bello, M; Taylor, L E; Wood, A J; London, N J

2000-03-01

This study aimed to develop an alternative graduated compression bandage for the treatment of venous leg ulcers. Alternative bandage components were identified and assessed for optimal performance as a graduated multi-layer compression bandage. Subsequently the physical characteristics and clinical efficacy of the optimal bandage combination was prospectively examined. Ten healthy limbs were used to develop the optimal combination and 20 limbs with venous ulceration to compare the physical properties of the two bandage types. Subsequently 42 consecutive ulcerated limbs were prospectively treated to examine the efficacy of the new bandage combination. The new combination produced graduated median (range) sub-bandage pressures (mmHg) as follows: ankle 59 (42-100), calf 36 (27-67) and knee 35 (16-67). Over a seven-day period this combination maintained a comparable level of compression with the Charing Cross system, and achieved an overall healing rate at one year of 88%. The described combination should be brought to the attention of healthcare professionals treating venous ulcers as a possible alternative to other forms of multi-layer graduated compression bandages pending prospective, randomised clinical trials.

Venous compression syndrome of internal jugular veins prevalence in patients with multiple sclerosis and chronic cerebro-spinal venous insufficiency.

PubMed

Mandolesi, Sandro; Niglio, Tarcisio; Orsini, Augusto; De Sio, Simone; d'Alessandro, Alessandro; Mandolesi, Dimitri; Fedele, Francesco; d'Alessandro, Aldo

2016-01-01

Analysis of the incidence of Venous Compression Syndrome (VCS) with full block of the flow of the internal jugular veins (IJVs) in patients with Multiple Sclerosis and Chronic cerebro-spinal venous insufficiency. We included 769 patients with MS and CCSVI (299 males, 470 females) and 210 controls without ms and ccsvi (92 males, 118 females). each subject was investigated by echo-color-doppler (ecd). morphological and hemodynamic ecd data were recorded by a computerized mem-net maps of epidemiological national observatory on ccsvi and they were analyzed by mem-net clinical analysis programs. VCS of IJVs occurs in 240 subjects affected by CCSVI and MS (31% of total) and in 12 controls (6% of total). The differences between the two groups are statistical significant (X² = 36.64, p<0.0001). Up to day there are no longitudinal studies that allow us to identify the WC of jugular and/or vertebral veins as etiology of a chronic neurodegenerative disease, but we note that Venous Compression Syndrome of IJVs is strongly associated with MS and CCSVI. Chronic Cerebro-Spinal Venous Insufficiency, Multiple Sclerosis, Venous Compression Syndrome.

A patient presenting with spinal cord compression who had two distinct follicular cell type thyroid carcinomas.

PubMed

Koca, E; Sokmensuer, C; Yildiz, B O; Engin, H; Bozkurt, M F; Aras, T; Barista, I; Gurlek, A

2004-06-01

A 61-yr-old woman presented with complaints of weakness and pain in her legs. A magnetic resonance imaging showed a 3 x 5.6 x 7.8 cm mass lesion destructing the T1 and T2 vertebral bodies and compressing the spinal cord. The mass was excised surgically. It was follicular carcinoma metastasis of the cervicodorsal region. Then, she underwent a total thyroidectomy. Pathological examination showed two different types of carcinomas in two different focuses; follicular carcinoma in the left lobe and follicular variant papillary carcinoma in the isthmic lobe. After the operation she was given 100 mCi 131I. This is the first report of a patient who had both metastatic follicular carcinoma and follicular variant papillary carcinoma together.

[Differentiated physiotherapy of lumbar pain].

PubMed

Chernyshova, L P; Galimova, E S

2011-01-01

The results of the present study confirm the efficacy of combined differential treatment of pain sensation in the lower back with the use of the up-to-date physiotherapeutic methods. The choice of a concrete method depended on the mechanism of development of the vertebral syndrome (compression, disfixation, disgenia or aseptic inflammation). The treatment resulted in the improvement of major integral characteristics of the pathological process, marked reduction in the duration of therapy, and significant prolongation of the remission period.

Medical Fitness for Expeditionary Missions: A NATO Guide for Assessing Deployability for Military Personnel with Medical Conditions. Task Group 174, Human Factors and Medicine Panel

DTIC Science & Technology

2013-07-30

preventing movement of the thrombus toward the lungs. Pulmonary embolism is the obstruction of a pulmonary artery due to the presence of air, fat , blood...Organization NSAID Nonsteroidal anti-inflammatory drugs OCD Obsessive-Compulsive Disorder PASI Psoriasis Area & Severity Index PE Pulmonary embolism PEF...as cancer, infection, cauda equina syndrome, spinal stenosis or radiculopathy, vertebral compression fracture or ankylosing spondylitis); OR

Kinking and Torsion Can Significantly Improve the Efficiency of Valveless Pumping in Periodically Compressed Tubular Conduits. Implications for Understanding of the Form-Function Relationship of Embryonic Heart Tubes.

PubMed

Hiermeier, Florian; Männer, Jörg

2017-11-19

Valveless pumping phenomena (peristalsis, Liebau-effect) can generate unidirectional fluid flow in periodically compressed tubular conduits. Early embryonic hearts are tubular conduits acting as valveless pumps. It is unclear whether such hearts work as peristaltic or Liebau-effect pumps. During the initial phase of its pumping activity, the originally straight embryonic heart is subjected to deforming forces that produce bending, twisting, kinking, and coiling. This deformation process is called cardiac looping. Its function is traditionally seen as generating a configuration needed for establishment of correct alignments of pulmonary and systemic flow pathways in the mature heart of lung-breathing vertebrates. This idea conflicts with the fact that cardiac looping occurs in all vertebrates, including gill-breathing fishes. We speculate that looping morphogenesis may improve the efficiency of valveless pumping. To test the physical plausibility of this hypothesis, we analyzed the pumping performance of a Liebau-effect pump in straight and looped (kinked) configurations. Compared to the straight configuration, the looped configuration significantly improved the pumping performance of our pump. This shows that looping can improve the efficiency of valveless pumping driven by the Liebau-effect. Further studies are needed to clarify whether this finding may have implications for understanding of the form-function relationship of embryonic hearts.

Failed Percutaneous Vertebroplasty Due to Insufficient Correction of Intravertebral Instability in Kummell's Disease: A Case Report.

PubMed

Kim, Jung Eun; Choi, Sang Sik; Lee, Mi Kyoung; Lee, Dong Kyu; Cho, Seung Inn

2017-11-01

Kummell's disease, caused by osteonecrosis of the vertebral body, is a cause of vertebral collapse. In Kummell's disease, intravertebral instability from nonunion between the cement and bone after percutaneous vertebroplasty (PVP) can cause persistent severe pain and dysfunction. A 75-year-old woman presented with severe pain in the lower back, both buttocks, groin, and both posterior thighs for a period of 30 days. Lumbar radiographs and magnetic resonance images showed an acute compression fracture of the first lumbar vertebra with an intravertebral cleft filled with fluid. The patient underwent PVP for the L1 compression fracture; however, this failed to provide sufficient pain relief. The patient was re-evaluated with dynamic radiography, and intravertebral instability and bone cement displacement of the L1 vertebra were detected. Repeat PVP was performed. After the procedure, intravertebral instability was restored and her pain completely subsided. PVP is a good treatment choice for symptomatic Kummell's disease. However, there is no consensus on the best technique of injecting bone cement to achieve optimal results. It is important to inject more bone cement than the volume of the intravertebral cleft to prevent instability caused by nonunion in PVP for Kummell's disease. We report a case of failed PVP because of insufficient correction of intravertebral instability in Kummell's, along with a review of the literature. © 2017 World Institute of Pain.

Kinking and Torsion Can Significantly Improve the Efficiency of Valveless Pumping in Periodically Compressed Tubular Conduits. Implications for Understanding of the Form-Function Relationship of Embryonic Heart Tubes

PubMed Central

Hiermeier, Florian; Männer, Jörg

2017-01-01

Valveless pumping phenomena (peristalsis, Liebau-effect) can generate unidirectional fluid flow in periodically compressed tubular conduits. Early embryonic hearts are tubular conduits acting as valveless pumps. It is unclear whether such hearts work as peristaltic or Liebau-effect pumps. During the initial phase of its pumping activity, the originally straight embryonic heart is subjected to deforming forces that produce bending, twisting, kinking, and coiling. This deformation process is called cardiac looping. Its function is traditionally seen as generating a configuration needed for establishment of correct alignments of pulmonary and systemic flow pathways in the mature heart of lung-breathing vertebrates. This idea conflicts with the fact that cardiac looping occurs in all vertebrates, including gill-breathing fishes. We speculate that looping morphogenesis may improve the efficiency of valveless pumping. To test the physical plausibility of this hypothesis, we analyzed the pumping performance of a Liebau-effect pump in straight and looped (kinked) configurations. Compared to the straight configuration, the looped configuration significantly improved the pumping performance of our pump. This shows that looping can improve the efficiency of valveless pumping driven by the Liebau-effect. Further studies are needed to clarify whether this finding may have implications for understanding of the form-function relationship of embryonic hearts. PMID:29367548

PREDICTING RETINOID RECEPTOR BINDING AFFINITY: COREPA-M APPLICATION

EPA Science Inventory

Retinoic acid and associated vitamin A derivatives comprise a class of endogenous hormones that activate different retinoic acid receptors RARs). Transcriptional events subsequent to this activation are key to controlling several aspects of vertebrate development. As such, identi...

Prestressing Shock Resistant Mechanical Components and Mechanisms Made from Hard, Superelastic Materials

NASA Technical Reports Server (NTRS)

DellaCorte, Christopher (Inventor)

2014-01-01

A method and an apparatus confer full superelastic properties to the active surface of a mechanical component constructed of a superelastic material prior to service. A compressive load is applied to the active surface of the mechanical component followed by removing the compressive load from the active surface whereby substantially all load strain is recoverable after applying and removing of subsequent compressive loads.

The Pixon Method for Data Compression Image Classification, and Image Reconstruction

NASA Technical Reports Server (NTRS)

Puetter, Richard; Yahil, Amos

2002-01-01

As initially proposed, this program had three goals: (1) continue to develop the highly successful Pixon method for image reconstruction and support other scientist in implementing this technique for their applications; (2) develop image compression techniques based on the Pixon method; and (3) develop artificial intelligence algorithms for image classification based on the Pixon approach for simplifying neural networks. Subsequent to proposal review the scope of the program was greatly reduced and it was decided to investigate the ability of the Pixon method to provide superior restorations of images compressed with standard image compression schemes, specifically JPEG-compressed images.

A comparison of high viscosity bone cement and low viscosity bone cement vertebroplasty for severe osteoporotic vertebral compression fractures.

PubMed

Zhang, Liang; Wang, Jingcheng; Feng, Xinmin; Tao, Yuping; Yang, Jiandong; Wang, Yongxiang; Zhang, Shengfei; Cai, Jun; Huang, Jijun

2015-02-01

To compare the clinical outcome and complications of high viscosity and low viscosity poly-methyl methacrylate bone cement PVP for severe OVCFs. From December 2010 to December 2012, 32 patients with severe OVCFs were randomly assigned to either group H using high viscosity cement (n=14) or group L using low viscosity cement (n=18). The clinical outcomes were assessed by the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), Short Form-36 General Health Survey (SF-36), kyphosis Cobb's angle, vertebral height, and complications. Significant improvement in the VAS, ODI, SF-36 scores, kyphosis Cobb's angle, and vertebral height were noted in both the groups, and there were no significant differences between the two groups. Cement leakage was seen less in group H. Postoperative assessment using computed tomography identified cement leakage in 5 of 17 (29.4%) vertebrae in group H and in 15 of 22 (68.2%) vertebrae in group L (P=0.025). The PVP using high viscosity bone cement can provide the same clinical outcome and fewer complications compared with PVP using low viscosity bone cement. Copyright © 2014. Published by Elsevier B.V.

Osteoporosis affects both post-yield microdamage accumulation and plasticity degradation in vertebra of ovariectomized rats

NASA Astrophysics Data System (ADS)

Li, Siwei; Niu, Guodong; Dong, Neil X.; Wang, Xiaodu; Liu, Zhongjun; Song, Chunli; Leng, Huijie

2017-04-01

Estrogen withdrawal in postmenopausal women increases bone loss and bone fragility in the vertebra. Bone loss with osteoporosis not only reduces bone mineral density (BMD), but actually alters bone quality, which can be comprehensively represented by bone post-yield behaviors. This study aimed to provide some information as to how osteoporosis induced by estrogen depletion could influence the evolution of post-yield microdamage accumulation and plastic deformation in vertebral bodies. This study also tried to reveal the part of the mechanisms of how estrogen deficiency-induced osteoporosis would increase the bone fracture risk. A rat bilateral ovariectomy (OVX) model was used to induce osteoporosis. Progressive cyclic compression loading was developed for vertebra testing to elucidate the post-yield behaviors. BMD, bone volume fraction, stiffness degradation, and plastic deformation evolution were compared among rats raised for 5 weeks (ovx5w and sham5w groups) and 35 weeks (ovx35w and sham35w groups) after sham surgery and OVX. The results showed that a higher bone loss in vertebral bodies corresponded to lower stiffness and higher plastic deformation. Thus, osteoporosis could increase the vertebral fracture risk probably through microdamage accumulation and plastic deforming degradation.

Evolution of the Rax family of developmental transcription factors in vertebrates.

PubMed

Orquera, Daniela P; de Souza, Flávio S J

2017-04-01

Rax proteins comprise a small family of paired-type, homeodomain-containing transcription factors with essential functions in eye and forebrain development. While invertebrates possess only one Rax gene, vertebrates can have several Rax paralogue genes, but the evolutionary history of the members of the family has not been studied in detail. Here, we present a thorough analysis of the evolutionary relationships between vertebrate Rax genes and proteins available in diverse genomic databases. Phylogenetic and synteny analyses indicate that Rax genes went through a duplication in an ancestor of all jawed vertebrates (Gnathostomata), giving rise to the ancestral vertebrate Rax1 and Rax2 genes. This duplication event is likely related to the proposed polyploidisations that occurred during early vertebrate evolution. Subsequent genome-wide duplications in the lineage of ray-finned fish (Actinopterygii) originated new Rax2 paralogues in the genomes of teleosts. In the lobe-finned fish lineage (Sarcopterygii), the N-terminal octapeptide domain of Rax2 was lost in a common ancestor of tetrapods, giving rise to a shorter version of Rax2 in this lineage. Within placental mammals, the Rax2 gene was lost altogether in an ancestor of rodents and lagomorphs (Glires). Finally, we discuss the scientific literature in the light of Rax gene evolution and propose new avenues of research on the function of this important family of transcriptional regulators. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Evolution of the shut-off steps of vertebrate phototransduction.

PubMed

Lamb, Trevor D; Patel, Hardip R; Chuah, Aaron; Hunt, David M

2018-01-01

Different isoforms of the genes involved in phototransduction are expressed in vertebrate rod and cone photoreceptors, providing a unique example of parallel evolution via gene duplication. In this study, we determine the molecular phylogeny of the proteins underlying the shut-off steps of phototransduction in the agnathan and jawed vertebrate lineages. For the G-protein receptor kinases (GRKs), the GRK1 and GRK7 divisions arose prior to the divergence of tunicates, with further expansion during the two rounds of whole-genome duplication (2R); subsequently, jawed and agnathan vertebrates retained different subsets of three isoforms of GRK. For the arrestins, gene expansion occurred during 2R. Importantly, both for GRKs and arrestins, the respective rod isoforms did not emerge until the second round of 2R, just prior to the separation of jawed and agnathan vertebrates. For the triplet of proteins mediating shut-off of the G-protein transducin, RGS9 diverged from RGS11, probably at the second round of 2R, whereas Gβ5 and R9AP appear not to have undergone 2R expansion. Overall, our analysis provides a description of the duplications and losses of phototransduction shut-off genes that occurred during the transition from a chordate with only cone-like photoreceptors to an ancestral vertebrate with both cone- and rod-like photoreceptors. © 2018 The Authors.

Brainstem removal using compressed air for subsequent bovine spongiform encephalopathy testing

PubMed Central

2005-01-01

Abstract The use of compressed air to expel the obex through a hole in the skull generated using a captured bolt stunner. The obex is the part of the brain that is tested for bovine spongiform encephalopathy. PMID:16018564

The loss and recovery of vertebrate vision examined in microplates.

PubMed

Thorn, Robert J; Clift, Danielle E; Ojo, Oladele; Colwill, Ruth M; Creton, Robbert

2017-01-01

Regenerative medicine offers potentially ground-breaking treatments of blindness and low vision. However, as new methodologies are developed, a critical question will need to be addressed: how do we monitor in vivo for functional success? In the present study, we developed novel behavioral assays to examine vision in a vertebrate model system. In the assays, zebrafish larvae are imaged in multiwell or multilane plates while various red, green, blue, yellow or cyan objects are presented to the larvae on a computer screen. The assays were used to examine a loss of vision at 4 or 5 days post-fertilization and a gradual recovery of vision in subsequent days. The developed assays are the first to measure the loss and recovery of vertebrate vision in microplates and provide an efficient platform to evaluate novel treatments of visual impairment.

Isogenic transgenic homozygous fish induced by artificial parthenogenesis.

PubMed

Nam, Y K; Cho, Y S; Kim, D S

2000-12-01

As a model system for vertebrate transgenesis, fish have many attractive advantages, especially with respect to the characteristics of eggs, allowing us to produce isogenic, transgenic, homozygous vertebrates by combining with chromosome-set manipulation. Here, we describe the large-scale production of isogenic transgenic homozygous animals using our experimental organism, the mud loach Misgurnus mizolepis, by the simple process of artificial parthenogenesis in a single generation. These isogenic fish have retained transgenic homozygous status in a stable manner during the subsequent 5 years, and exhibited increased levels of transgene expression. Furthermore, their isogenic nature was confirmed by cloned transgenic homozygous offspring produced via another step of parthenogenic reproduction of the isogenic homozygous transgenic fish. These results demonstrate that a combination of transgenesis and artificial parthenogenesis will make the rapid utilization of genetically pure homozygous transgenic system in vertebrate transgenesis possible.

Diagnosis of Lumbar Foraminal Stenosis using Diffusion Tensor Imaging.

PubMed

Eguchi, Yawara; Ohtori, Seiji; Suzuki, Munetaka; Oikawa, Yasuhiro; Yamanaka, Hajime; Tamai, Hiroshi; Kobayashi, Tatsuya; Orita, Sumihisa; Yamauchi, Kazuyo; Suzuki, Miyako; Aoki, Yasuchika; Watanabe, Atsuya; Kanamoto, Hirohito; Takahashi, Kazuhisa

2016-02-01

Diagnosis of lumbar foraminal stenosis remains difficult. Here, we report on a case in which bilateral lumbar foraminal stenosis was difficult to diagnose, and in which diffusion tensor imaging (DTI) was useful. The patient was a 52-year-old woman with low back pain and pain in both legs that was dominant on the right. Right lumbosacral nerve compression due to a massive uterine myoma was apparent, but the leg pain continued after a myomectomy was performed. No abnormalities were observed during nerve conduction studies. Computed tomography and magnetic resonance imaging indicated bilateral L5 lumbar foraminal stenosis. DTI imaging was done. The extraforaminal values were decreased and tractography was interrupted in the foraminal region. Bilateral L5 vertebral foraminal stenosis was treated by transforaminal lumbar interbody fusion and the pain in both legs disappeared. The case indicates the value of DTI for diagnosing vertebral foraminal stenosis.

A new efficient method for color image compression based on visual attention mechanism

NASA Astrophysics Data System (ADS)

Shao, Xiaoguang; Gao, Kun; Lv, Lily; Ni, Guoqiang

2010-11-01

One of the key procedures in color image compression is to extract its region of interests (ROIs) and evaluate different compression ratios. A new non-uniform color image compression algorithm with high efficiency is proposed in this paper by using a biology-motivated selective attention model for the effective extraction of ROIs in natural images. When the ROIs have been extracted and labeled in the image, the subsequent work is to encode the ROIs and other regions with different compression ratios via popular JPEG algorithm. Furthermore, experiment results and quantitative and qualitative analysis in the paper show perfect performance when comparing with other traditional color image compression approaches.

A classification of growth friendly spine implants.

PubMed

Skaggs, David L; Akbarnia, Behrooz A; Flynn, John M; Myung, Karen S; Sponseller, Paul D; Vitale, Michael G

2014-01-01

Various types of spinal implants have been used with the objective of minimizing spinal deformities while maximizing the spine and thoracic growth in a growing child with a spinal deformity. The aim of this study was to describe a classification system of growth friendly spinal implants to allow researchers and clinicians to have a common language and facilitate comparative studies. Growth friendly spinal implant systems fall into 3 categories based upon the forces of correction the implants exert on the spine, which are as follows: Distraction-based systems correct spinal deformities by mechanically applying a distractive force across a deformed segment with anchors at the top and bottom of the implants, which commonly attach to the spine, rib, and/or the pelvis. The present examples of distraction-based implants are spine-based or rib-based growing rods, vertical expandable titanium rib prosthesis, and remotely expandable devices. Compression-based systems correct spinal deformities with a compressive force applied to the convexity of the curve causing convex growth inhibition. This compressive force may be generated both mechanically at the time of implantation, as well as over time resulting from longitudinal growth of vertebral endplates hindered by the spinal implants. Examples of compression-based systems are vertebral staples and tethers. Guided growth systems correct spinal deformity by anchoring multiple vertebrae (usually including the apical vertebrae) to rods with mechanical forces including translation at the time of the initial implant. The majority of the anchors are not rigidly attached to the rods, thus permitting longitudinal growth over time as the anchors slide over the rods. Examples of guided growth systems include the Luque trolley and Shilla. Each system has its benefits and shortcomings. Knowledge of the fundamental principles upon which these systems are based may aid the clinician to choose an appropriate treatment for patients. Having a common language for these systems may aid in comparative research. Vertical expandable titanium rib prosthesis is used with humanitarian exemption. The other devices mentioned in this manuscript are not approved for growing constructs by the Food and Drug Administration and are used off-label.

Cat-scratch disease. Subtle vertebral bone marrow abnormalities demonstrated by MR imaging and radionuclide bone scan.

PubMed

Wilson, J D; Castillo, M

1995-01-01

Cat-scratch disease (CSD) is a benign, self-limited cause of lymphadenitis occurring mainly in children and young adults. Its etiology is a delicate, small gram-negative pleomorphic bacillus. Less common manifestations of CSD are seen in 5% of patients and include Parinaud's oculoglandular syndrome (with enlargement of the preauricular nodes), parotid gland enlargement, encephalitis, radiculopathy, pneumonitis, erythema nodosum, thrombocytopenia, and lytic bone lesions. We describe a patient in whom magnetic resonance imaging initially detected subtle vertebral bone marrow abnormalities that correlated with the site of abnormality on a subsequent radionuclide bone scan.

Loss of Type I Collagen Telopeptide Lysyl Hydroxylation Causes Musculoskeletal Abnormalities in a Zebrafish Model of Bruck Syndrome

PubMed Central

Gistelinck, Charlotte; Witten, Paul Eckhard; Huysseune, Ann; Symoens, Sofie; Malfait, Fransiska; Larionova, Daria; Simoens, Pascal; Dierick, Manuel; Van Hoorebeke, Luc; De Paepe, Anne; Kwon, Ronald Y; Weis, MaryAnn; Eyre, David R; Willaert, Andy; Coucke, Paul J

2017-01-01

Bruck syndrome (BS) is a disorder characterized by joint flexion contractures and skeletal dysplasia that shows strong clinical overlap with the brittle bone disease Osteogenesis Imperfecta (OI). BS is caused by bi-allelic mutations in either the FKBP10 or the PLOD2 gene. PLOD2 encodes the lysyl hydroxylase 2 (LH2) enzyme, which is responsible for the hydroxylation of lysine residues in fibrillar collagen telopeptides. This hydroxylation directs cross-linking of collagen fibrils in the extracellular matrix, which is necessary to provide stability and tensile integrity to the collagen fibrils. To further elucidate the function of LH2 in vertebrate skeletal development, we created a zebrafish model harboring a homozygous plod2 nonsense mutation resulting in reduced telopeptide hydroxylation and cross-linking of bone type I collagen. Adult plod2 mutants present with a shortened body axis and severe skeletal abnormalities with evidence of bone fragility and fractures. The vertebral column of plod2 mutants is short and scoliotic with compressed vertebrae that show excessive bone formation at the vertebral end plates, and increased tissue mineral density in the vertebral centra. The muscle fibers of mutant zebrafish have a reduced diameter near the horizontal myoseptum. The endomysium, a layer of connective tissue ensheathing the individual muscle fibers, is enlarged. Transmission electron microscopy of mutant vertebral bone shows type I collagen fibrils that are less organized with loss of the typical plywood-like structure. In conclusion, plod2 mutant zebrafish show molecular and tissue abnormalities in the musculoskeletal system that are concordant with clinical findings in BS patients. Therefore, the plod2 zebrafish mutant is a promising model for the elucidation of the underlying pathogenetic mechanisms leading to BS and the development of novel therapeutic avenues in this syndrome. PMID:27541483

Pathogenesis of lumbar spine disease in mucopolysaccharidosis VII

PubMed Central

Smith, Lachlan J; Baldo, Guilherme; Wu, Susan; Liu, Yuli; Whyte, Michael P; Giugliani, Roberto; Elliott, Dawn M; Haskins, Mark E; Ponder, Katherine P

2012-01-01

Mucopolysaccharidosis type VII (MPS VII) is characterized by deficient β-glucuronidase (GUSB) activity, which leads to accumulation of chondroitin, heparan and dermatan sulfate glycosaminoglycans (GAGs), and multisystemic disease. MPS VII patients can develop kypho-scoliotic deformity and spinal cord compression due to disease of intervertebral discs, vertebral bodies, and associated tissues. We have previously demonstrated in MPS VII dogs that intervertebral discs degenerate, vertebral bodies have irregular surfaces, and vertebral body epiphyses have reduced calcification, but the pathophysiological mechanisms underlying these changes are unclear. We hypothesized that some of these manifestations could be due to upregulation of destructive proteases, possibly via the binding of GAGs to Toll-like receptor 4 (TLR4), as has been proposed for other tissues in MPS models. In this study, the annulus fibrosus of the intervertebral disc of 6 month-old MPS VII dogs had cathepsin B and K activities that were 117- and 2-fold normal, respectively, which were associated with elevations in mRNA levels for cathepsins as well as TLR4. The epiphyses of MPS VII dogs had a marked elevation in mRNA for the cartilage-associated gene collagen II, consistent with a developmental delay in the conversion of the cartilage to bone in this region. A spine from a human patient with MPS VII exhibited similar increased cartilage in the vertebral bodies adjacent to the end plates, disorganization of the intervertebral discs, and irregular vertebral end plate morphology. These data suggest that the pathogenesis of destructive changes in the spine in MPS VII may involve upregulation of cathepsins. Inhibition of destructive proteases, such as cathepsins, might reduce spine disease in patients with MPS VII or related disorders. PMID:22513347

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

PubMed

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

2018-06-01

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

Echo-Planar Imaging-Based, J-Resolved Spectroscopic Imaging for Improved Metabolite Detection in Prostate Cancer

DTIC Science & Technology

2016-12-01

tiple dimensions (20). Hu et al. employed pseudo-random phase-encoding blips during the EPSI readout to create nonuniform sampling along the spatial...resolved MRSI with Nonuniform Undersampling and Compressed Sensing 514 30.5 Prior-knowledge Fitting for Metabolite Quantitation 515 30.6 Future Directions... NONUNIFORM UNDERSAMPLING AND COMPRESSED SENSING Nonuniform undersampling (NUS) of k-space and subsequent reconstruction using compressed sensing (CS

Microstructure and Texture Evolution in a Yttrium-Containing ZM31 Alloy: Effect of Pre- and Post-deformation Annealing

NASA Astrophysics Data System (ADS)

Tahreen, N.; Zhang, D. F.; Pan, F. S.; Jiang, X. Q.; Li, D. Y.; Chen, D. L.

2016-12-01

Microstructure and texture evolution of as-extruded ZM31 magnesium alloys with different amounts of yttrium (Y) during pre- and post-deformation annealing were examined with special attention given to the effect of Y on recrystallization. It was observed that the extruded ZM31 alloys exhibited a basal texture with the basal planes parallel to the extrusion direction (ED). The compression of the extruded alloys in the ED to a strain amount of 10 pct resulted in c-axes of hcp unit cells rotating toward the anti-compression direction due to the occurrence of extension twinning. Annealing of the extruded alloys altered the microstructure and texture, and the subsequent compression after annealing showed a relatively weak texture and a lower degree of twinning. A reverse procedure of pre-compression and subsequent annealing was found to further weaken the texture with a more scattered distribution of orientations and to lead to the vanishing of the original basal texture. With increasing Y content, both the extent of extension twinning during compression and the fraction of recrystallization during annealing decreased due to the role of Y present in the substitutional solid solution and in the second-phase particles, leading to a significant increase in the compressive yield strength.

Proton spectra diagnostics for shock-compression studies

NASA Astrophysics Data System (ADS)

Welch, D. R.; Harris, D. B.; Bennish, A. H.; Miley, G. H.

1984-12-01

The energy spectra of fusion products escaping long-pulse-length laser-imploded deuterium-tritium filled glass microballoons have been measured with a time-of-flight spectrometer. The D(d,p)T reaction proton energy spectra showed two distinct peaks, indicating two burn phases in the target. The first burn phase is attributed to a spherically converging shock, while the second is attributed to subsequent compression heating. The analysis of these spectra provides the first conclusive proof of significant compression yields in these targets, where approximately half of the yield occurs during the compression burn phase.

Imaging diagnosis--Spontaneous subperiosteal vertebral hemorrhage in a greyhound.

PubMed

Theobald, Anita; Dennis, Ruth; Beltran, Elsa

2014-01-01

A 4-year-old, spayed female greyhound dog was presented with an acute onset of paraplegia. There was no known history of trauma or coagulopathy. Spinal cord compression was identified on MRI. Intra-operative evaluation revealed the presence of a large subperiosteal hematoma and a smaller epidural hematoma. To the authors' knowledge, this is the first report of a spinal subperiosteal hematoma diagnosed antemortem through MRI, with surgical exploration and successful treatment in a dog. © 2013 American College of Veterinary Radiology.

Osteopenia and bone fractures in a man with anorexia nervosa and hypogonadism

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

Rigotti, N.A.; Neer, R.M.; Jameson, L.

Women with anorexia nervosa have reduced skeletal mass. Both anorexia and osteopenia are less common in men. We describe a 22-year-old man with anorexia nervosa and severe osteopenia involving both cortical and trabecular bone who developed a pelvic fracture and multiple vertebral compression fractures. He was found to have secondary hypogonadotropic hypogonadism that was reversible with weight gain. This case illustrates the need to consider osteopenia as a potential complication of anorexia nervosa in males as well as females.

Postnatal progression of bone disease in the cervical spines of mucopolysaccharidosis I dogs

PubMed Central

Chiaro, Joseph A; Baron, Matthew D; del Alcazar, Chelsea; O’Donnell, Patricia; Shore, Eileen M; Elliott, Dawn M; Ponder, Katherine P; Haskins, Mark E; Smith, Lachlan J

2013-01-01

Introduction Mucopolysaccharidosis I (MPS I) is a lysosomal storage disorder characterized by deficient α-L-iduronidase activity leading to accumulation of poorly degraded dermatan and heparan sulfate glycosaminoglycans (GAGs). MPS I is associated with significant cervical spine disease, including vertebral dysplasia, odontoid hypoplasia, and accelerated disc degeneration, leading to spinal cord compression and kypho-scoliosis. The objective of this study was to establish the nature and rate of progression of cervical vertebral bone disease in MPS I using a canine model. Methods C2 vertebrae were obtained post-mortem from normal and MPS I dogs at 3, 6 and 12 months-of-age. Morphometric parameters and mineral density for the vertebral trabecular bone and odontoid process were determined using micro-computed tomography. Vertebrae were then processed for paraffin histology, and cartilage area in both the vertebral epiphyses and odontoid process were quantified. Results Vertebral bodies of MPS I dogs had lower trabecular bone volume/total volume (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD) than normals at all ages. For MPS I dogs, BV/TV, Tb.Th and BMD plateaued after 6 months-of-age. The odontoid process appeared morphologically abnormal for MPS I dogs at 6 and 12 months-of-age, although BV/TV and TMD were not significantly different from normals. MPS I dogs had significantly more cartilage in the vertebral epiphyses at both 3 and 6 months-of-age. At 12 months-of-age, epiphyseal growth plates in normal dogs were absent, but in MPS I dogs they persisted. Conclusions In this study we report reduced trabecular bone content and mineralization, and delayed cartilage to bone conversion in MPS I dogs from 3 months-of-age, which may increase vertebral fracture risk and contribute to progressive deformity. The abnormalities of the odontoid process we describe likely contribute to increased incidence of atlanto-axial subluxation observed clinically. Therapeutic strategies that enhance bone formation may decrease incidence of spine disease in MPS I patients. PMID:23563357

Evaluation of injectable silica-embedded nanohydroxyapatite bone substitute in a rat tibia defect model

PubMed Central

Xu, Weiguo; Ganz, Cornelia; Weber, Ulf; Adam, Martin; Holzhüter, Gerd; Wolter, Daniel; Frerich, Bernhard; Vollmar, Brigitte; Gerber, Thomas

2011-01-01

In clinical practice, vertebral compression fractures occur after trauma and osteoporosis. Kyphoplasty is a minimally invasive procedure using bone filler material for the treatment of such fractures. A full synthetic injectable bone substitute (SIBS) was manufactured by means of spray drying. The aim of this study was to characterize the SIBS and to analyze the remodelling process during degradation of the biomaterial and new bone formation after implantation. SIBS is an aqueous suspension of donut-like microparticles. These microparticles consist of nanocrystallites of synthetic hydroxyapatite embedded in amorphous silica gel. After implantation of SIBS in a proximal tibial diaphyseal defect in 52 rats, grafts were harvested for subsequent analysis on different days. Newly formed bone originating from endosteum was observed on day 6. Hematomas in the medullary space and cortical wounds disappeared on day 12. The wound region was completely replaced by a composite of newly formed cancellous bone, extracellular matrix, and SIBS. At day 63 the cortical defect was fully healed by bone, while newly formed bone in the medullary space almost disappeared and was replaced with bone marrow. In conclusion, SIBS demonstrated a unique structure with osteoinductive and bioresorbable properties, which induced fast bone regeneration. Therefore, a clinical application of SIBS for kyphoplasty is promising. PMID:21845044

Malignant pheochromocytoma with multiple vertebral metastases causing acute incomplete paralysis during pregnancy: Literature review with one case report.

PubMed

Liu, Shuzhong; Song, An; Zhou, Xi; Kong, Xiangyi; Li, William A; Wang, Yipeng; Liu, Yong

2017-11-01

We present a rare case of malignant pheochromocytoma with thoracic metastases during pregnancy that presented with symptoms of myelopathy and was treated with circumferential decompression, stabilization, and radiation. The management of this unique case is not well documented. The clinical manifestations, imaging results, pathological characteristics, treatment and prognosis of the case were analyzed. A 26-year-old pregnant woman with a history of paroxysmal hypertension during the second trimester presented with lower extremity weakness, numbness, urinary incontinence, and back pain. Imaging studies revealed a right adrenal pheochromocytoma, multiple metastases at T8, T11, T12, and the pelvis girdle causing significant multilevel cord compression and significant osteolytic lesions at T11 and T12. We believe this is the first reported case of metastatic pheochromocytoma of the thoracic spine presenting with symptoms of myelopathy during pregnancy. A healthy neonate was delivered by emergency caesarean section at 34 weeks. Subsequently, the patient underwent a circumferential spinal cord decompression and a stabilization procedure. The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 6-month follow-up visit. This article emphasizes that metastatic pheochromocytoma of the spine, although rare, should be part of the differential when a patient presents with elevated blood pressure, weakness, and urinary incontinence.

3D Bioprinting of Developmentally Inspired Templates for Whole Bone Organ Engineering.

PubMed

Daly, Andrew C; Cunniffe, Gráinne M; Sathy, Binulal N; Jeon, Oju; Alsberg, Eben; Kelly, Daniel J

2016-09-01

The ability to print defined patterns of cells and extracellular-matrix components in three dimensions has enabled the engineering of simple biological tissues; however, bioprinting functional solid organs is beyond the capabilities of current biofabrication technologies. An alternative approach would be to bioprint the developmental precursor to an adult organ, using this engineered rudiment as a template for subsequent organogenesis in vivo. This study demonstrates that developmentally inspired hypertrophic cartilage templates can be engineered in vitro using stem cells within a supporting gamma-irradiated alginate bioink incorporating Arg-Gly-Asp adhesion peptides. Furthermore, these soft tissue templates can be reinforced with a network of printed polycaprolactone fibers, resulting in a ≈350 fold increase in construct compressive modulus providing the necessary stiffness to implant such immature cartilaginous rudiments into load bearing locations. As a proof-of-principal, multiple-tool biofabrication is used to engineer a mechanically reinforced cartilaginous template mimicking the geometry of a vertebral body, which in vivo supported the development of a vascularized bone organ containing trabecular-like endochondral bone with a supporting marrow structure. Such developmental engineering approaches could be applied to the biofabrication of other solid organs by bioprinting precursors that have the capacity to mature into their adult counterparts over time in vivo. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The origin and evolution of the neural crest

PubMed Central

Donoghue, Philip C. J.; Graham, Anthony; Kelsh, Robert N.

2009-01-01

Summary Many of the features that distinguish the vertebrates from other chordates are derived from the neural crest, and it has long been argued that the emergence of this multipotent embryonic population was a key innovation underpinning vertebrate evolution. More recently, however, a number of studies have suggested that the evolution of the neural crest was less sudden than previously believed. This has exposed the fact that neural crest, as evidenced by its repertoire of derivative cell types, has evolved through vertebrate evolution. In this light, attempts to derive a typological definition of neural crest, in terms of molecular signatures or networks, are unfounded. We propose a less restrictive, embryological definition of this cell type that facilitates, rather than precludes, investigating the evolution of neural crest. While the evolutionary origin of neural crest has attracted much attention, its subsequent evolution has received almost no attention and yet it is more readily open to experimental investigation and has greater relevance to understanding vertebrate evolution. Finally, we provide a brief outline of how the evolutionary emergence of neural crest potentiality may have proceeded, and how it may be investigated. PMID:18478530

Maggots as a wound debridement agent for chronic venous leg ulcers under graduated compression bandages: A randomised controlled trial.

PubMed

Davies, C E; Woolfrey, G; Hogg, N; Dyer, J; Cooper, A; Waldron, J; Bulbulia, R; Whyman, M R; Poskitt, K R

2015-12-01

Slough in chronic venous leg ulcers may be associated with delayed healing. The purpose of this study was to assess larval debridement in chronic venous leg ulcers and to assess subsequent effect on healing. All patients with chronic leg ulcers presenting to the leg ulcer service were evaluated for the study. Exclusion criteria were: ankle brachial pressure indices <0.85 or >1.25, no venous reflux on duplex and <20% of ulcer surface covered with slough. Participants were randomly allocated to either 4-layer compression bandaging alone or 4-layer compression bandaging + larvae. Surface areas of ulcer and slough were assessed on day 4; 4-layer compression bandaging was then continued and ulcer size was measured every 2 weeks for up to 12 weeks. A total of 601 patients with chronic leg ulcers were screened between November 2008 and July 2012. Of these, 20 were randomised to 4-layer compression bandaging and 20 to 4-layer compression bandaging + larvae. Median (range) ulcer size was 10.8 (3-21.3) cm(2) and 8.1 (4.3-13.5) cm(2) in the 4-layer compression bandaging and 4-layer compression bandaging + larvae groups, respectively (Mann-Whitney U test, P = 0.184). On day 4, median reduction in slough area was 3.7 cm(2) in the 4-layer compression bandaging group (P < 0.05) and 4.2 cm(2) (P < 0.001) in the 4-layer compression bandaging + larvae group. Median percentage area reduction of slough was 50% in the 4-layer compression bandaging group and 84% in the 4-layer compression bandaging + larvae group (Mann-Whitney U test, P < 0.05). The 12-week healing rate was 73% and 68% in the 4-layer compression bandaging and 4-layer compression bandaging + larvae groups, respectively (Kaplan-Meier analysis, P = 0.664). Larval debridement therapy improves wound debridement in chronic venous leg ulcers treated with multilayer compression bandages. However, no subsequent improvement in ulcer healing was demonstrated. © The Author(s) 2014.

Hemodynamic Deterioration in Lateral Compression Pelvic Fracture After Prehospital Pelvic Circumferential Compression Device Application.

PubMed

Garner, Alan A; Hsu, Jeremy; McShane, Anne; Sroor, Adam

Increased fracture displacement has previously been described with the application of pelvic circumferential compression devices (PCCDs) in patients with lateral compression-type pelvic fracture. We describe the first reported case of hemodynamic deterioration temporally associated with the prehospital application of a PCCD in a patient with a complex acetabular fracture with medial displacement of the femoral head. Active hemorrhage from a site adjacent to the acetabular fracture was subsequently demonstrated on angiography. Caution in the application of PCCDs to patients with lateral compression-type fractures is warranted. Copyright © 2017 Air Medical Journal Associates. All rights reserved.

Investigating the Influence of Environmental Factors on Pesticide Exposure in Amphibians

EPA Science Inventory

Environmental factors such as temporal weather patterns and soil characterization coupled with pesticide application rates are known to influence exposure and subsequent absorption of these compounds in amphibians. Amphibians are a unique class of vertebrates due to their varied ...

Real-world effectiveness of osteoporosis therapies for fracture reduction in post-menopausal women.

PubMed

Yusuf, Akeem A; Cummings, Steven R; Watts, Nelson B; Feudjo, Maurille Tepie; Sprafka, J Michael; Zhou, Jincheng; Guo, Haifeng; Balasubramanian, Akhila; Cooper, Cyrus

2018-03-21

Studies examining real-world effectiveness of osteoporosis therapies are beset by limitations due to confounding by indication. By evaluating longitudinal changes in fracture incidence, we demonstrated that osteoporosis therapies are effective in reducing fracture risk in real-world practice settings. Osteoporosis therapies have been shown to reduce incidence of vertebral and non-vertebral fractures in placebo-controlled randomized clinical trials. However, information on the real-world effectiveness of these therapies is limited. We examined fracture risk reduction in older, post-menopausal women treated with osteoporosis therapies. Using Medicare claims, we identified 1,278,296 women age ≥ 65 years treated with zoledronic acid, oral bisphosphonates, denosumab, teriparatide, or raloxifene. Fracture incidence rates before and after treatment initiation were described to understand patients' fracture risk profile, and fracture reduction effectiveness of each therapy was evaluated as a longitudinal change in incidence rates. Fracture incidence rates increased during the period leading up to treatment initiation and were highest in the 3-month period most proximal to treatment initiation. Fracture incidence rates following treatment initiation were significantly lower than before treatment initiation. Compared with the 12-month pre-index period, there were reductions in clinical vertebral fractures for denosumab (45%; 95% confidence interval [CI] 39-51%), zoledronic acid (50%; 95% CI 47-52%), oral bisphosphonates (24%; 95% CI 22-26%), and teriparatide (72%; 95% CI 69-75%) during the subsequent 12 months. Relative to the first 3 months after initiation, clinical vertebral fractures were reduced for denosumab (51%; 95% CI 42-59%), zoledronic acid (25%; 95% CI 17-32%), oral bisphosphonates (23%; 95% CI 20-26%), and teriparatide (64%; 95% CI 58-69%) during the subsequent 12 months. In summary, reductions in fracture incidence over time were observed in cohorts of patients treated with osteoporosis therapies.

The decreased responsiveness of lumbar muscle spindles to a prior history of spinal muscle lengthening is graded with the magnitude of change in vertebral position

PubMed Central

Ge, Weiqing; Pickar, Joel G.

2013-01-01

In the lumbar spine, muscle spindle responsiveness is affected by the duration and direction of a lumbar vertebra’s positional history. The purpose of the present study was to determine the relationship between changes in the magnitude of a lumbar vertebra’s positional history and the responsiveness of lumbar muscle spindles to a subsequent vertebral position and subsequent vertebral movement. Neural activity from multifidus and longissimus muscle spindle afferents in deeply anesthetized cats was recorded while creating positional histories of the L6 vertebra. History was induced using a displacement-controlled feedback motor. It held the L6 vertebra for 4 seconds at an intermediate position (hold-intermediate at 0mm) and at 7 positions from 0.07 to 1.55mm more ventralward and dorsalward which lengthened (hold-long) and shortened (hold-short) the lumbar muscles. Following the conditioning hold positions, L6 was returned to the intermediate position. Muscle spindle discharge at this position and during a lengthening movement was compared between hold-intermediate and hold-short conditionings and between hold-intermediate and hold-short conditionings. We found that regardless of conditioning magnitude, the 7 shortening magnitudes similarly increased muscle spindle responsiveness to both vertebral position and movement. In contrast, the 7 lengthening magnitudes produced a graded decrease in responsiveness to both position and movement. The decrease to position became maximal following conditioning magnitudes of ~0.75 mm. The decrease to movement did not reach a maximum even with conditioning magnitudes of ~1.55 mm. The data suggest that the fidelity of proprioceptive information from muscle spindles in the low back is influenced by small changes in the previous length history of lumbar muscles. PMID:22721784

Aggravation and subsequent disappearance of cervical disc herniation after cervical open-door laminoplasty: A case report.

PubMed

Meng, Yang; Wang, Xiaofei; Wang, Beiyu; Wu, Tingkui; Liu, Hao

2018-03-01

Cervical open-door laminoplasty can enlarge the volume of the cervical vertebral canal and thus has become an effective and safe treatment for multilevel cervical disc herniation and cervical stenosis. Some post-surgery complications exist, such as reduction of cervical alignment and local kyphosis. However, aggravation of cervical disc herniation at the surgical level during short-term follow-up has not been discussed. Additionally, spontaneous disappearance of herniated disc pulposus is a common phenomenon in the lumbar region but is relatively rare in the cervical region. A 42-year-old female presented with a 7-year history of neck pain and a 2-year history of paresthesia and weakness in the upper and lower limbs. The sensations and muscle strength of both upper and lower limbs were decreased. The radiological findings showed that the Pavlov ratios from C3-7 were decreased obviously. Osteophytes as well as spinal cord compression were observed at C4/5, C5/6, and C6/7. Considering the symptoms and clinical examinations, the patient was diagnosed with cervical stenosis. We performed cervical open-door laminoplasty at C3-7 to enlarge the space of the cervical vertebral canal. At the 6-month post-surgery follow-up, the patient showed obvious improvement in paresthesia and weakness in the upper limbs. The cervical disc herniation at C3/4 was aggravated. However, at the 18-month follow-up, the symptoms were relieved, and the herniated cervical disc at C3/4 spontaneously disappeared without any special treatment. We suggest that the attachment points of deep muscles in the neck region should be carefully protected during this surgery. Patients who undergo cervical open-door laminoplasty should pay attention to their cervical position and perform neck exercises to train their neck muscles. MRI is an important imaging method to observe dynamic changes in herniated discs for patients with cervical disc herniation.

Confirmation of Romer's Gap as a low oxygen interval constraining the timing of initial arthropod and vertebrate terrestrialization

PubMed Central

Ward, Peter; Labandeira, Conrad; Laurin, Michel; Berner, Robert A.

2006-01-01

The first terrestrialization of species that evolved from previously aquatic taxa was a seminal event in evolutionary history. For vertebrates, one of the most important terrestrialized groups, this event was interrupted by a time interval known as Romer's Gap, for which, until recently, few fossils were known. Here, we argue that geochronologic range data of terrestrial arthropods show a pattern similar to that of vertebrates. Thus, Romer's Gap is real, occupied an interval from 360 million years before present (MYBP) to 345 MYBP, and occurred when environmental conditions were unfavorable for air-breathing, terrestrial animals. These model results suggest that atmospheric oxygen levels were the major driver of successful terrestrialization, and a low-oxygen interval accounts for Romer's Gap. Results also show that terrestrialization among members of arthropod and vertebrate clades occurred in two distinct phases. The first phase was a 65-million-year (My) interval from 425 to 360 MYBP, representing an earlier, prolonged event of complete arthropod terrestrialization of smaller-sized forms (425–385 MYBP) and a subsequent, modest, and briefer event of incipient terrestrialization of larger-sized, aquatic vertebrates (385–360 MYBP). The second phase began at 345 MYBP, characterized by numerous new terrestrial species emerging in both major clades. The first and second terrestrialization phases bracket Romer's Gap, which represents a depauperate spectrum of major arthropod and vertebrate taxa before a major Late Paleozoic colonization of terrestrial habitats. PMID:17065318

Evolutionary history of the alpha2,8-sialyltransferase (ST8Sia) gene family: Tandem duplications in early deuterostomes explain most of the diversity found in the vertebrate ST8Sia genes

PubMed Central

2008-01-01

Background The animal sialyltransferases, which catalyze the transfer of sialic acid to the glycan moiety of glycoconjugates, are subdivided into four families: ST3Gal, ST6Gal, ST6GalNAc and ST8Sia, based on acceptor sugar specificity and glycosidic linkage formed. Despite low overall sequence identity between each sialyltransferase family, all sialyltransferases share four conserved peptide motifs (L, S, III and VS) that serve as hallmarks for the identification of the sialyltransferases. Currently, twenty subfamilies have been described in mammals and birds. Examples of the four sialyltransferase families have also been found in invertebrates. Focusing on the ST8Sia family, we investigated the origin of the three groups of α2,8-sialyltransferases demonstrated in vertebrates to carry out poly-, oligo- and mono-α2,8-sialylation. Results We identified in the genome of invertebrate deuterostomes, orthologs to the common ancestor for each of the three vertebrate ST8Sia groups and a set of novel genes named ST8Sia EX, not found in vertebrates. All these ST8Sia sequences share a new conserved family-motif, named "C-term" that is involved in protein folding, via an intramolecular disulfide bridge. Interestingly, sequences from Branchiostoma floridae orthologous to the common ancestor of polysialyltransferases possess a polysialyltransferase domain (PSTD) and those orthologous to the common ancestor of oligosialyltransferases possess a new ST8Sia III-specific motif similar to the PSTD. In osteichthyans, we have identified two new subfamilies. In addition, we describe the expression profile of ST8Sia genes in Danio rerio. Conclusion Polysialylation appeared early in the deuterostome lineage. The recent release of several deuterostome genome databases and paralogons combined with synteny analysis allowed us to obtain insight into events at the gene level that led to the diversification of the ST8Sia genes, with their corresponding enzymatic activities, in both invertebrates and vertebrates. The initial expansion and subsequent divergence of the ST8Sia genes resulted as a consequence of a series of ancient duplications and translocations in the invertebrate genome long before the emergence of vertebrates. A second subset of ST8sia genes in the vertebrate genome arose from whole genome duplication (WGD) R1 and R2. Subsequent selective ST8Sia gene loss is responsible for the characteristic ST8Sia gene expression pattern observed today in individual species. PMID:18811928

Evolutionary history of the alpha2,8-sialyltransferase (ST8Sia) gene family: tandem duplications in early deuterostomes explain most of the diversity found in the vertebrate ST8Sia genes.

PubMed

Harduin-Lepers, Anne; Petit, Daniel; Mollicone, Rosella; Delannoy, Philippe; Petit, Jean-Michel; Oriol, Rafael

2008-09-23

The animal sialyltransferases, which catalyze the transfer of sialic acid to the glycan moiety of glycoconjugates, are subdivided into four families: ST3Gal, ST6Gal, ST6GalNAc and ST8Sia, based on acceptor sugar specificity and glycosidic linkage formed. Despite low overall sequence identity between each sialyltransferase family, all sialyltransferases share four conserved peptide motifs (L, S, III and VS) that serve as hallmarks for the identification of the sialyltransferases. Currently, twenty subfamilies have been described in mammals and birds. Examples of the four sialyltransferase families have also been found in invertebrates. Focusing on the ST8Sia family, we investigated the origin of the three groups of alpha2,8-sialyltransferases demonstrated in vertebrates to carry out poly-, oligo- and mono-alpha2,8-sialylation. We identified in the genome of invertebrate deuterostomes, orthologs to the common ancestor for each of the three vertebrate ST8Sia groups and a set of novel genes named ST8Sia EX, not found in vertebrates. All these ST8Sia sequences share a new conserved family-motif, named "C-term" that is involved in protein folding, via an intramolecular disulfide bridge. Interestingly, sequences from Branchiostoma floridae orthologous to the common ancestor of polysialyltransferases possess a polysialyltransferase domain (PSTD) and those orthologous to the common ancestor of oligosialyltransferases possess a new ST8Sia III-specific motif similar to the PSTD. In osteichthyans, we have identified two new subfamilies. In addition, we describe the expression profile of ST8Sia genes in Danio rerio. Polysialylation appeared early in the deuterostome lineage. The recent release of several deuterostome genome databases and paralogons combined with synteny analysis allowed us to obtain insight into events at the gene level that led to the diversification of the ST8Sia genes, with their corresponding enzymatic activities, in both invertebrates and vertebrates. The initial expansion and subsequent divergence of the ST8Sia genes resulted as a consequence of a series of ancient duplications and translocations in the invertebrate genome long before the emergence of vertebrates. A second subset of ST8sia genes in the vertebrate genome arose from whole genome duplication (WGD) R1 and R2. Subsequent selective ST8Sia gene loss is responsible for the characteristic ST8Sia gene expression pattern observed today in individual species.

Spinal cord compression in two related Ursus arctos horribilis.

PubMed

Thomovsky, Stephanie A; Chen, Annie V; Roberts, Greg R; Schmidt, Carrie E; Layton, Arthur W

2012-09-01

Two 15-yr-old grizzly bear littermates were evaluated within 9 mo of each other with the symptom of acute onset of progressive paraparesis and proprioceptive ataxia. The most significant clinical examination finding was pelvic limb paresis in both bears. Magnetic resonance examinations of both bears showed cranial thoracic spinal cord compression. The first bear had left-sided extradural, dorsolateral spinal cord compression at T3-T4. Vertebral canal stenosis was also observed at T2-T3. Images of the second bear showed lateral spinal cord compression from T2-T3 to T4-T5. Intervertebral disk disease and associated spinal cord compression was also observed at T2-T3 and T3-T4. One grizzly bear continued to deteriorate despite reduced exercise, steroid, and antibiotic therapy. The bear was euthanized, and a necropsy was performed. The postmortem showed a spinal ganglion cyst that caused spinal cord compression at the level of T3-T4. Wallerian-like degeneration was observed from C3-T6. The second bear was prescribed treatment that consisted of a combination of reduced exercise and steroid therapy. He continued to deteriorate with these medical therapies and was euthanized 4 mo after diagnosis. A necropsy showed hypertrophy and protrusion of the dorsal longitudinal ligament at T2-T3 and T3-T4, with resulting spinal cord compression in this region. Wallerian-like degeneration was observed from C2-L1. This is one of few case reports that describes paresis in bears. It is the only case report, to the authors' knowledge, that describes spinal magnetic resonance imaging findings in a grizzly bear and also the only report that describes a cranial thoracic myelopathy in two related grizzly bears with neurologic signs.

Depression of the Thoracolumbar Posterior Vertebral Body on the Estimation of Cement Leakage in Vertebroplasty and Kyphoplasty Operations

PubMed Central

Chen, Hao; Jia, Pu; Bao, Li; Feng, Fei; Yang, He; Li, Jin-Jun; Tang, Hai

2015-01-01

Background: The cross-section of thoracolumbar vertebral body is kidney-shaped with depressed posterior boundary. The anterior wall of the vertebral canal is separated from the posterior wall of the vertebral body on the lateral X-ray image. This study was designed to determine the sagittal distance between the anterior border of the vertebral canal and the posterior border of the vertebral body (DBCV) and to analyze the potential role of DBCV in the estimation of cement leakage during percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP). Methods: We retrospectively recruited 233 patients who had osteoporotic vertebral compression fractures and were treated with PVP or PKP. Computed tomography images of T11–L2 normal vertebrae were measured to obtain DBCV. The distance from cement to the posterior wall of the vertebral body (DCPW) of thoracolumbar vertebrae was measured from C-arm images. The selected vertebrae were divided into two groups according to DCPW, with the fracture levels, fracture grades and leakage rates of the two groups compared. A relative operating characteristic (ROC) curve was applied to determine whether the DCPW difference can be used to estimate the degree of cement leakage. The data were processed by statistical software SPSS version 21.0 using independent sample t-test and Chi-square tests. Results: The maximum DBCV was 6.40 mm and the average DBCV was 3.74 ± 0.95 mm. DBCV appeared to be longer in males than in females, but the difference was not statistically significant. The average DCPW of type-B leakage vertebrae (2.59 ± 1.20 mm) was shorter than that of other vertebrae (7.83 ± 2.38 mm, P < 0.001). The leakage rate of group DCPW ≤6.40 mm was lower than that of group DCPW >6.40 mm for type-C and type-S, but much higher for type-B. ROC curve revealed that DCPW only has a predictive value for type-B leakage (area under the curve: 0.98, 95% confidence interval: 0.95–0.99, P < 0.001), and when the cut-off value was 4.05 mm, the diagnostic sensitivity and the specificity were 94.87% and 93.02%, respectively. Conclusions: Depression of the thoracolumbar posterior vertebral body may be informative for the estimation of cement location on C-arm images. To reduce type-B leakage, DCPW should be made longer than DBCV on C-arm images for safety during PVP or PKP. PMID:26612289

Depression of the Thoracolumbar Posterior Vertebral Body on the Estimation of Cement Leakage in Vertebroplasty and Kyphoplasty Operations.

PubMed

Chen, Hao; Jia, Pu; Bao, Li; Feng, Fei; Yang, He; Li, Jin-Jun; Tang, Hai

2015-12-05

The cross-section of thoracolumbar vertebral body is kidney-shaped with depressed posterior boundary. The anterior wall of the vertebral canal is separated from the posterior wall of the vertebral body on the lateral X-ray image. This study was designed to determine the sagittal distance between the anterior border of the vertebral canal and the posterior border of the vertebral body (DBCV) and to analyze the potential role of DBCV in the estimation of cement leakage during percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP). We retrospectively recruited 233 patients who had osteoporotic vertebral compression fractures and were treated with PVP or PKP. Computed tomography images of T11-L2 normal vertebrae were measured to obtain DBCV. The distance from cement to the posterior wall of the vertebral body (DCPW) of thoracolumbar vertebrae was measured from C-arm images. The selected vertebrae were divided into two groups according to DCPW, with the fracture levels, fracture grades and leakage rates of the two groups compared. A relative operating characteristic (ROC) curve was applied to determine whether the DCPW difference can be used to estimate the degree of cement leakage. The data were processed by statistical software SPSS version 21.0 using independent sample t-test and Chi-square tests. The maximum DBCV was 6.40 mm and the average DBCV was 3.74 ± 0.95 mm. DBCV appeared to be longer in males than in females, but the difference was not statistically significant. The average DCPW of type-B leakage vertebrae (2.59 ± 1.20 mm) was shorter than that of other vertebrae (7.83 ± 2.38 mm, P < 0.001). The leakage rate of group DCPW ≤6.40 mm was lower than that of group DCPW >6.40 mm for type-C and type-S, but much higher for type-B. ROC curve revealed that DCPW only has a predictive value for type-B leakage (area under the curve: 0.98, 95% confidence interval: 0.95-0.99, P < 0.001), and when the cut-off value was 4.05 mm, the diagnostic sensitivity and the specificity were 94.87% and 93.02%, respectively. Depression of the thoracolumbar posterior vertebral body may be informative for the estimation of cement location on C-arm images. To reduce type-B leakage, DCPW should be made longer than DBCV on C-arm images for safety during PVP or PKP.

[Mechanical studies of lumbar interbody fusion implants].

PubMed

Bader, R J; Steinhauser, E; Rechl, H; Mittelmeier, W; Bertagnoli, R; Gradinger, R

2002-05-01

In addition to autogenous or allogeneic bone grafts, fusion cages composed of metal or plastic are being used increasingly as spacers for interbody fusion of spinal segments. The goal of this study was the mechanical testing of carbon fiber reinforced plastic (CFRP) fusion cages used for anterior lumbar interbody fusion. With a special testing device according to American Society for Testing and Materials (ASTM) standards, the mechanical properties of the implants were determined under four different loading conditions. The implants (UNION cages, Medtronic Sofamor Danek) provide sufficient axial compression, shear, and torsional strength of the implant body. Ultimate axial compression load of the fins is less than the physiological compression loads at the lumbar spine. Therefore by means of an appropriate surgical technique parallel grooves have to be reamed into the endplates of the vertebral bodies according to the fin geometry. Thereby axial compression forces affect the implants body and the fins are protected from damaging loading. Using a supplementary anterior or posterior instrumentation, in vivo failure of the fins as a result of physiological shear and torsional spinal loads is unlikely. Due to specific complications related to autogenous or allogeneic bone grafts, fusion cages made of metal or carbon fiber reinforced plastic are an important alternative implant in interbody fusion.

Loading simulation of lumbar spine vertebrae during a compression test using the finite elements method and trabecular bone strength properties, determined by means of nanoindentations.

PubMed

Bouzakis, K D; Mitsi, S; Michailidis, N; Mirisidis, I; Mesomeris, G; Maliaris, G; Korlos, A; Kapetanos, G; Antonarakos, P; Anagnostidis, K

2004-06-01

The mechanical strength properties of lumbar spine vertebrae are of great importance in a wide range of applications. Herein, through nanoindentations and appropriate evaluation of the corresponding results, trabecular bone struts stress-strain characteristics can be determined. In the frame of the present paper, an L2 fresh cadaveric vertebra, from which posterior elements were removed, was subjected to compression. With the aid of developed finite elements method based algorithms, the cortical shell and the cancellous core bulk elasticity moduli and stresses were determined, whereas the tested vertebra geometrical model used in these algorithms was considered as having a compound structure, consisting of the cancellous bone surrounded by the cortical shell. Moreover nanoindentations were conducted and an appropriate evaluation method of the obtained results was applied to extract stress-strain curves of individual lumbar spine vertebra trabecular bone struts. These data were used in the mathematical description of the vertebrae compression test. The vertebral cancellous bone structure was simulated by a beam elements network, possessing an equivalent porosity and different stiffnesses in vertical and horizontal direction. Thus, the measured course of the compression load versus the occurring specimen deformation was verified.

The variability of vertebral body volume and pain associated with osteoporotic vertebral fractures: conservative treatment versus percutaneous transpedicular vertebroplasty.

PubMed

Andrei, Diana; Popa, Iulian; Brad, Silviu; Iancu, Aida; Oprea, Manuel; Vasilian, Cristina; Poenaru, Dan V

2017-05-01

Osteoporotic vertebral fractures (OVF) can lead to late collapse which often causes kyphotic spinal deformity, persistent back pain, decreased lung capacity, increased fracture risk and increased mortality. The purpose of our study is to compare the efficacy and safety of vertebroplasty against conservative management of osteoporotic vertebral fractures without neurologic symptoms. A total of 66 patients with recent OVF on MRI examination were included in the study. All patients were admitted from September 2009 to September 2012. The cohort was divided into two groups. The first study group consisted of 33 prospectively followed consecutive patients who suffered 40 vertebral osteoporotic fractures treated by percutaneous vertebroplasty (group 1), and the control group consisted of 33 patients who suffered 41 vertebral osteoporotic fractures treated conservatively because they refused vertebroplasty (group 2). The data collection has been conducted in a prospective registration manner. The inclusion criteria consisted of painful OVF matched with imagistic findings. We assessed the results of pain relief and minimal sagittal area of the vertebral body on the axial CT scan at presentation, after the intervention, at six and 12 months after initial presentation. Vertebroplasty with poly(methyl methacrylate) (PMMA) was performed in 30 patients on 39 VBs, including four thoracic vertebras, 27 vertebras of the thoracolumbar jonction and eight lumbar vertebras. Group 2 included 30 patients with 39 OVFs (four thoracic vertebras, 23 vertebras of the thoracolumbar junction and 11 lumbar vertebras). There was no significant difference in VAS scores before treatment (p = 0.229). The mean VAS was 5.90 in Group 1 and 6.28 in Group 2 before the treatment. Mean VAS after vertebroplasty was 0.85 in Group 1. The mean VAS at six months was 0.92 in Group 1 and 3.00 in Group 2 (p < 0.05). The mean VAS at 12 months was 0.92 in Group 1 and 2.36 in Group 2. The mean improvement rate in VAS scores was 84.40% and 62.42%, respectively (p < 0.05). For Group 1, mean area of the VBs measured on sagital CT images was 8.288 at the initial presentation, 8.554 postoperatively, 8.541 at five months and 8.508 at 12 months, respectively, and 8.388 at the initial presentation, 7.976 at six months and 7.585 at 12 months for Group 2 (Fig. 4). Although conservative treatment is fundamental and achieves good symptom control, in patients who suffer osteoporotic compression fractures (OCF), the incidence of late collapse is high and the prognosis is poor. In order to relieve the pain and avoid VB collapse, vertebroplasty is the recommended treatment in OCFs. Considering the above findings, the dilemma is whether vertebroplasty can change the natural history (pain and deformity) of OCFs. In our study on OVF, vertebroplasty delivered superior clinical and radiological outcomes over the first year from intervention when compared to conservative treatment of patients with osteoporotic compression fractures without neurological deficit. We believe that the possibility of evolution towards progressive kyphosis is sufficient to justify prophylactic and therapeutic intervention such as vertebroplasty, a minor gesture compared with extensive correction surgery and stabilization.

The orthopedic diseases of ancient Egypt.

PubMed

Fritsch, Klaus O; Hamoud, Heshem; Allam, Adel H; Grossmann, Alexander; Nur El-Din, Abdel-Halim; Abdel-Maksoud, Gomaa; Soliman, Muhammad Al-Tohamy; Badr, Ibrahim; Sutherland, James D; Sutherland, M Linda; Akl, Mahmoud; Finch, Caleb E; Thomas, Gregory S; Wann, L Samuel; Thompson, Randall C

2015-06-01

CT scanning of ancient human remains has the potential to provide insights into health and diseases. While Egyptian mummies have undergone CT scans in prior studies, a systematic survey of the orthopedic conditions afflicting a group of these ancient individuals has never been carried out. We performed whole body CT scanning on 52 ancient Egyptian mummies using technique comparable to that of medical imaging. All of the large joints and the spine were systematically examined and osteoarthritic (OA) changes were scored 0-4 using Kellgren and Lawrence classification. The cruciate ligaments and menisci could be identified frequently. There were much more frequent OA changes in the spine (25 mummies) than in the large joints (15 cases of acromioclavicular and/or glenohumeral joint OA changes, five involvement of the ankle, one in the elbow, four in the knee, and one in the hip). There were six cases of scoliosis. Individual mummies had the following conditions: juvenile aseptic necrosis of the hip (Perthes disease), stage 4 osteochondritis dissecans of the knee, vertebral compression fracture, lateral patella-femoral joint hyper-compression syndrome, severe rotator cuff arthropathy, rotator cuff impingement, hip pincer impingement, and combined fracture of the greater trochantor and vertebral bodies indicating obvious traumatic injury. This report includes the most ancient discovery of several of these syndromes. Ancient Egyptians often suffered painful orthopedic conditions. The high frequency of scoliosis merits further study. The pattern of degenerative changes in the spine and joints may offer insights into activity levels of these people. © 2015 Wiley Periodicals, Inc.

Cost analysis of skeletal-related events in Spanish patients with bone metastases from solid tumours.

PubMed

Durán, I; Garzón, C; Sánchez, A; García-Carbonero, I; Pérez-Gracia, J L; Seguí-Palmer, M Á; Wei, R; Restovic, G; Gasquet, J A; Gutiérrez, L

2014-03-01

To estimate the cost per skeletal-related event (SRE) in patients with bone metastases secondary to solid tumours in the Spanish healthcare setting. Patients diagnosed with bone metastases secondary to breast, prostate or lung cancer were included in this multicentre, observational study. SREs are defined as pathologic fracture (vertebral and non-vertebral fracture), radiation to bone, spinal cord compression or surgery to bone. Health resource utilisation associated with these events (inpatient stays, outpatient, emergency room and home health visits, nursing home stays and procedures) were collected retrospectively for all SREs that occurred in the 97 days prior to enrolment and prospectively during follow-up. Unit costs were obtained from the 2010 eSalud healthcare costs database. A total of 93 Spanish patients with solid tumours were included (31 had breast cancer, 21 prostate cancer and 41 lung cancer), contributing a total of 143 SREs to this cost analysis. Inpatient stays (between 9.0 and 29.9 days of mean length of stay per inpatient stay by SRE type) and outpatient visits (between 1.7 and 6.4 mean visits per SRE type) were the most frequently reported types of health resources utilised. The mean cost per SRE was between 2,377.79 (radiation to bone) and 7,902.62 (spinal cord compression). SREs are associated with a significant consumption of healthcare resources that generate a substantial economic burden for the Spanish healthcare system.

Hemilingual spasm: defining a new entity, its electrophysiological correlates and surgical treatment through microvascular decompression.

PubMed

Osburn, Leisha L; Møller, Aage R; Bhatt, Jay R; Cohen-Gadol, Aaron A

2010-07-01

We report on vascular compression syndrome of the 12th cranial nerve (hypoglossal), an occurrence not previously reported, and demonstrate, through corresponding objective electrophysiological evidence, that microvascular decompression of the hypoglossal nerve root can cure hemilingual spasm. A 52-year-old man had lower face muscle twitching and tongue spasms, which worsened with talking, chewing, or emotional stress. Carbamazepine offered only temporary relief, and relief from injections of botulinum toxin was insignificant. He was referred for surgical treatment. High-resolution magnetic resonance imaging of his posterior fossa contents revealed no obvious evidence of any compressive vessel along the facial nerve, but a compressive vessel along the hypoglossal nerve was apparent. The presence of preoperative tongue spasms encouraged interoperative monitoring of tongue motor responses. The facial nerve exit zone was explored, but microsurgical inspection of the seventh/eighth cranial nerve complex did not reveal any compressive vessel. However, at the anterolateral aspect of the medulla oblongata, the hypoglossal nerve was clearly compressed and distorted laterally by a large tortuous vertebral artery. When the artery was mobilized away from the nerve, the abnormal late electromyographic response to transcranial electrical stimulation disappeared; immediately after shredded Teflon was interpositioned between the artery and the nerve, the abnormal spontaneous tongue fasciculation also disappeared. The patient has remained spasm free 6 months after surgery. Hemilingual spasm may be caused by vascular contact/compression along cranial nerve XII at the lower brainstem and belong to the same family of cranial nerve hyperactivity disorders as hemifacial spasm.

Fatal fat embolism syndrome in a case of isolated L1 vertebral fracture-dislocation.

PubMed

Yamauchi, Koun; Fushimi, Kazunari; Ikeda, Tsuneko; Fukuta, Masashi

2013-11-01

Although fat embolism syndrome is a well-known complication of fractures of the long bones or pelvis, fat embolism syndrome occurring subsequent to fracture of the lumbar spine is rare. We report a fatal case of fat embolism syndrome characterized by fat and bone marrow embolism that occurred 36 h after an isolated fracture-dislocation of the L1 vertebra. A postmortem examination was performed and pathological finding demonstrated fat and bone marrow tissue which were disseminated in the bilateral pulmonary arteries. We need to be aware of the possibility of fat embolism syndrome as a complication of spinal fractures, including isolated vertebral body fractures.

Eye evolution at high resolution: the neuron as a unit of homology.

PubMed

Erclik, Ted; Hartenstein, Volker; McInnes, Roderick R; Lipshitz, Howard D

2009-08-01

Based on differences in morphology, photoreceptor-type usage and lens composition it has been proposed that complex eyes have evolved independently many times. The remarkable observation that different eye types rely on a conserved network of genes (including Pax6/eyeless) for their formation has led to the revised proposal that disparate complex eye types have evolved from a shared and simpler prototype. Did this ancestral eye already contain the neural circuitry required for image processing? And what were the evolutionary events that led to the formation of complex visual systems, such as those found in vertebrates and insects? The recent identification of unexpected cell-type homologies between neurons in the vertebrate and Drosophila visual systems has led to two proposed models for the evolution of complex visual systems from a simple prototype. The first, as an extension of the finding that the neurons of the vertebrate retina share homologies with both insect (rhabdomeric) and vertebrate (ciliary) photoreceptor cell types, suggests that the vertebrate retina is a composite structure, made up of neurons that have evolved from two spatially separate ancestral photoreceptor populations. The second model, based largely on the conserved role for the Vsx homeobox genes in photoreceptor-target neuron development, suggests that the last common ancestor of vertebrates and flies already possessed a relatively sophisticated visual system that contained a mixture of rhabdomeric and ciliary photoreceptors as well as their first- and second-order target neurons. The vertebrate retina and fly visual system would have subsequently evolved by elaborating on this ancestral neural circuit. Here we present evidence for these two cell-type homology-based models and discuss their implications.

The contribution of thoracic vertebral deformity and arthropathy to trunk pain in patients with chronic obstructive pulmonary disease (COPD).

PubMed

Chen, Yi-Wen; Coxson, Harvey O; Coupal, Tyler M; Lam, Stephen; Munk, Peter L; Leipsic, Jonathon; Reid, W Darlene

2018-04-01

Pain, commonly localized to the trunk in individuals with COPD, may be due to osteoporosis-related vertebral deformity and chest wall hyper-expansion causing misalignment of joints between the ribs and vertebrae. The purpose of this study was to determine if thoracic vertebral deformity and arthropathy were independent contributors to trunk pain in COPD patients compared to people with a significant smoking history. Participants completed the Brief Pain Inventory (BPI) on the same day as chest CT scans and spirometry. Current and ex-smokers were separated into COPD (n = 91) or non-COPD (n = 80) groups based on spirometry. Subsequently, CT images were assessed for thoracic vertebral deformity, bone attenuation values, and arthropathy of thoracic vertebral joints. The trunk area was the most common pain location in both COPD and non-COPD groups. Thoracic vertebral deformity and costotransverse joint arthropathy were independent contributors to trunk pain in COPD patients (adjusted OR = 3.55 and 1.30, respectively) whereas alcohol consumption contributed to trunk pain in the non-COPD group (adjusted OR = 0.35 in occasional alcohol drinkers; 0.08 in non-alcohol drinkers). The spinal deformity index and the number of narrowed disc spaces were significantly positively related to the BPI intensity, interference, and total scores significantly in COPD patients. Trunk pain, at least in part, is caused by thoracic vertebral deformity, and costotransverse and intervertebral arthropathy in patients living with COPD. The results of this study provided the foundation for the management of pain, which requires further exploration. Copyright © 2018 Elsevier Ltd. All rights reserved.

Vertebral artery origin stent placement with distal protection: technical and clinical results.

PubMed

Qureshi, A I; Kirmani, J F; Harris-Lane, P; Divani, A A; Ahmed, S; Ebrihimi, A; Al Kawi, A; Janjua, N

2006-05-01

To report the feasibility, safety, and 1-month results of performing stent placement for vertebral origin stenosis with the use of a distal protection device. Distal protection devices have been shown to reduce the number of cerebral emboli and subsequent ischemic events when used as adjuncts to percutaneous carotid intervention; however, one case of the use of a distal protection device for vertebral artery has been reported in the literature. We retrospectively determined rates of technical success and 1-month stroke or death associated with stent placement by using distal protection (Filter EX; Boston Scientific, Natick, Mass) in patients with symptomatic vertebral artery origin stenosis. Technical success was defined as successful deployment of distal protection device and stent at target lesion followed by successful retrieval of the device and a final residual stenosis of less than 30%. Other outcomes ascertained included any stroke, death, and semiquantitative assessment of particulate material retained by the filter device. The mean age of the 12 treated patients was 68 years (range, 52-88 years) and the group included 9 men and 3 women. The mean percentage of vertebral artery origin stenosis was 71 +/- 6%. Femoral and radial approaches were used in 9 and 3 cases, respectively. Technical success was achieved in 11 of the 12 patients in whom distal protection device placement was attempted. Postprocedure residual stenosis was 5 +/- 4%. Eight devices held macroscopically visible embolic debris (large and small amounts in 3 and 5 devices, respectively). No stroke or death was observed in the 1-month follow-up. The present study demonstrates the feasibility of performing stent placement for vertebral artery origin stenosis by using a distal protection device. Further studies are required to determine the effectiveness of this approach for vertebral artery origin atherosclerosis.

Origin of the vertebrate body plan via mechanically biased conservation of regular geometrical patterns in the structure of the blastula.

PubMed

Edelman, David B; McMenamin, Mark; Sheesley, Peter; Pivar, Stuart

2016-09-01

We present a plausible account of the origin of the archetypal vertebrate bauplan. We offer a theoretical reconstruction of the geometrically regular structure of the blastula resulting from the sequential subdivision of the egg, followed by mechanical deformations of the blastula in subsequent stages of gastrulation. We suggest that the formation of the vertebrate bauplan during development, as well as fixation of its variants over the course of evolution, have been constrained and guided by global mechanical biases. Arguably, the role of such biases in directing morphology-though all but neglected in previous accounts of both development and macroevolution-is critical to any substantive explanation for the origin of the archetypal vertebrate bauplan. We surmise that the blastula inherently preserves the underlying geometry of the cuboidal array of eight cells produced by the first three cleavages that ultimately define the medial-lateral, dorsal-ventral, and anterior-posterior axes of the future body plan. Through graphical depictions, we demonstrate the formation of principal structures of the vertebrate body via mechanical deformation of predictable geometrical patterns during gastrulation. The descriptive rigor of our model is supported through comparisons with previous characterizations of the embryonic and adult vertebrate bauplane. Though speculative, the model addresses the poignant absence in the literature of any plausible account of the origin of vertebrate morphology. A robust solution to the problem of morphogenesis-currently an elusive goal-will only emerge from consideration of both top-down (e.g., the mechanical constraints and geometric properties considered here) and bottom-up (e.g., molecular and mechano-chemical) influences. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

A second corticotropin-releasing hormone gene (CRH2) is conserved across vertebrate classes and expressed in the hindbrain of a basal neopterygian fish, the spotted gar (Lepisosteus oculatus).

PubMed

Grone, Brian P; Maruska, Karen P

2015-05-01

To investigate the origins of the vertebrate stress-response system, we searched sequenced vertebrate genomes for genes resembling corticotropin-releasing hormone (CRH). We found that vertebrate genomes possess, in addition to CRH, another gene that resembles CRH in sequence and syntenic environment. This paralogous gene was previously identified only in the elephant shark (a holocephalan), but we find it also in marsupials, monotremes, lizards, turtles, birds, and fishes. We examined the relationship of this second vertebrate CRH gene, which we name CRH2, to CRH1 (previously known as CRH) and urocortin1/urotensin1 (UCN1/UTS1) in primitive fishes, teleosts, and tetrapods. The paralogs CRH1 and CRH2 likely evolved via duplication of CRH during a whole-genome duplication early in the vertebrate lineage. CRH2 was subsequently lost in both teleost fishes and eutherian mammals but retained in other lineages. To determine where CRH2 is expressed relative to CRH1 and UTS1, we used in situ hybridization on brain tissue from spotted gar (Lepisosteus oculatus), a neopterygian fish closely related to teleosts. In situ hybridization revealed widespread distribution of both crh1 and uts1 in the brain. Expression of crh2 was restricted to the putative secondary gustatory/secondary visceral nucleus, which also expressed calcitonin-related polypeptide alpha (calca), a marker of parabrachial nucleus in mammals. Thus, the evolutionary history of CRH2 includes restricted expression in the brain, sequence changes, and gene loss, likely reflecting release of selective constraints following whole-genome duplication. The discovery of CRH2 opens many new possibilities for understanding the diverse functions of the CRH family of peptides across vertebrates. © 2015 Wiley Periodicals, Inc.

[Experiment of porous calcium phosphate/bone matrix gelatin composite cement for repairing lumbar vertebral bone defect in rabbit].

PubMed

Wang, Song; Yang, Han; Yang, Jian; Kang, Jianping; Wang, Qing; Song, Yueming

2017-12-01

To investigate the effect of a porous calcium phosphate/bone matrix gelatin (BMG) composite cement (hereinafter referred to as the "porous composite cement") for repairing lumbar vertebral bone defect in a rabbit model. BMG was extracted from adult New Zealand rabbits according to the Urist's method. Poly (lactic-co-glycolic) acid (PLGA) microsphere was prepared by W/O/W double emulsion method. The porous composite cement was developed by using calcium phosphate cement (CPC) composited with BMG and PLGA microsphere. The physicochemical characterizations of the porous composite cement were assessed by anti-washout property, porosity, and biomechanical experiment, also compared with the CPC. Thirty 2-month-old New Zealand rabbits were used to construct vertebral bone defect at L 3 in size of 4 mm×3 mm×3 mm. Then, the bone defect was repaired with porous composite cement (experimental group, n =15) or CPC (control group, n =15). At 4, 8, and 12 weeks after implantation, each bone specimen was assessed by X-ray films for bone fusion, micro-CT for bone mineral density (BMD), bone volume fraction (BVF), trabecular thickness (Tb. Th.), trabecular number (Tb.N.), and trabecular spacing (Tb. Sp.), and histological section with toluidine blue staining for new-born bone formation. The study demonstrated well anti-washout property in 2 groups. The porous composite cement has 55.06%±1.18% of porosity and (51.63±6.73) MPa of compressive strength. The CPC has 49.38%±1.75% of porosity and (63.34±3.27) MPa of compressive strength. There were significant differences in porosity and compressive strength between different cements ( t =4.254, P =0.006; t =2.476, P =0.034). X-ray films revealed that the zone between the cement and host bone gradually blurred with the time extending. At 12 weeks after implantation, the zone was disappeared in the experimental group, but clear in the control group. There were significant differences in BMD, BVF, Tb. Th., Tb. N., and Tb. Sp. between 2 groups at each time point ( P <0.05). Histological observation revealed that there was new-born bone in the cement with the time extending in 2 groups. Among them, bony connection was observed between the new-born bone and the host in the experimental group, which was prior to the control group. The porous composite cement has dual bioactivity of osteoinductivity and osteoconductivity, which are effective to promote bone defect healing and reconstruction.

The standardized creation of a lumbar spine vertebral compression fracture in a sheep osteoporosis model induced by ovariectomy, corticosteroid therapy and calcium/phosphorus/vitamin D-deficient diet.

PubMed

Eschler, Anica; Röpenack, Paula; Herlyn, Philipp K E; Roesner, Jan; Pille, Kristin; Büsing, Kirsten; Vollmar, Brigitte; Mittlmeier, Thomas; Gradl, Georg

2015-10-01

Vertebral compression fractures (VCFs) are one of the most common injuries in the aging population presenting with an annual incidence of 1.4 million new cases in Europe. Current treatment strategies focus on cement-associated solutions (kyphoplasty/vertebroplasty techniques). Specific cement-associated problems as leakage, embolism and the adjacent fracture disease are reported adding to open questions like general fracture healing properties of the osteoporotic spine. In order to analyze those queries animal models are of great interest; however, both technical difficulties in the induction of experimental osteoporosis in animal as well as the lack of a standardized fracture model impede current and future in vivo studies. This study introduces a standardized animal model of an osteoporotic VCF type A3.1 that may enable further in-depth analysis of the afore mentioned topics. Twenty-four 5-year-old female Merino sheep (mean body weight: 67 kg; range 57-79) were ovariectomized (OP1) and underwent 5.5 months of weekly corticosteroid injections (dexamethasone and dexamethasone-sodium-phosphate), adding to a calcium/phosphorus/vitamin D-deficient diet. Osteoporosis induction was documented by pQCT and micro-CT BMD (bone mineral density) as well as 3D histomorphometric analysis postoperatively of the sheep distal radius and spine. Non osteoporotic sheep served as controls. Induction of a VCF of the second lumbar vertebra was performed via a mini-lumbotomy surgical approach with a standardized manual compression mode (OP2). PQCT analysis revealed osteoporosis of the distal radius with significantly reduced BMD values (0.19 g/cm(3), range 0.13-0.22 vs. 0.27 g/cm(3), range 0.23-0.32). Micro-CT documented significant lowering of BMD values for the second lumbar vertebrae (0.11 g/cm(3), range 0.10-0.12) in comparison to the control group (0.14 g/cm(3), range 0.12-0.17). An incomplete burst fracture type A3.1 was achieved in all cases and resulted in a significant decrease in body angle and vertebral height (KA 4.9°, range: 2-12; SI 4.5%, range: 2-12). With OP1, one minor complication (lesion of small bowel) occurred, while no complications occurred with OP2. A suitable spinal fracture model for creation of VCFs in osteoporotic sheep was developed. The technique may promote the development of improved surgical solutions for VCF treatment in the experimental and clinical setting. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pathological characteristics of spine metastases treated with high-dose single-fraction stereotactic radiosurgery.

PubMed

Katsoulakis, Evangelia; Laufer, Ilya; Bilsky, Mark; Agaram, Narasimhan P; Lovelock, Michael; Yamada, Yoshiya

2017-01-01

OBJECTIVE Spine radiosurgery is increasingly being used to treat spinal metastases. As patients are living longer because of the increasing efficacy of systemic agents, appropriate follow-up and posttreatment management for these patients is critical. Tumor progression after spine radiosurgery is rare; however, vertebral compression fractures are recognized as a more common posttreatment effect. The use of radiographic imaging alone posttreatment may makeit difficult to distinguish tumor progression from postradiation changes such as fibrosis. This is the largest series from a prospective database in which the authors examine histopathology of samples obtained from patients who underwent surgical intervention for presumed tumor progression or mechanical pain secondary to compression fracture. The majority of patients had tumor ablation and resulting fibrosis rather than tumor progression. The aim of this study was to evaluate tumor histopathology and characteristics of patients who underwent pathological sampling because of radiographic tumor progression, fibrosis, or collapsed vertebrae after receiving high-dose single-fraction stereotactic radiosurgery. METHODS Between January 2005 and January 2014, a total of 582 patients were treated with linear accelerator-based single-fraction (18-24 Gy) stereotactic radiosurgery. The authors retrospectively identified 30 patients (5.1%) who underwent surgical intervention for 32 lesions with vertebral cement augmentation for either mechanical pain or instability secondary to vertebral compression fracture (n = 17) or instrumentation (n = 15) for radiographic tumor progression. Radiation and surgical treatment, histopathology, and long-term outcomes were reviewed. Survival and time to recurrence were calculated using the Kaplan-Meier method. RESULTS The mean age at the time of radiosurgery was 59 years (range 36-80 years). The initial pathological diagnoses were obtained for all patients and primarily included radioresistant tumor types, including renal cell carcinoma in 7 (22%), melanoma in 6 (19%), lung carcinoma in 4 (12%), and sarcoma in 3 (9%). The median time to surgical intervention was 24.7 months (range 1.6-50.8 months). The median follow-up and overall survival for all patients were 42.5 months and 41 months (overall survival range 7-86 months), respectively. The majority of assessed lesions showed no evidence of tumor on pathological review (25 of 32, 78%), while a minority of lesions revealed residual tumor (7 of 32, 22%). The median survival for patients after tumor recurrence was 5 months (range 2-70 months). CONCLUSIONS High-dose single-fraction radiosurgery is tumor ablative in the majority of instances. In a minority of cases, tumor persists and salvage treatments should be considered.

Pathological characteristics of spine metastases treated with high-dose single-fraction stereotactic radiosurgery

PubMed Central

Katsoulakis, Evangelia; Laufer, Ilya; Bilsky, Mark; Agaram, Narasimhan P.; Lovelock, Michael; Yamada, Yoshiya

2017-01-01

OBJECTIVE Spine radiosurgery is increasingly being used to treat spinal metastases. As patients are living longer because of the increasing efficacy of systemic agents, appropriate follow-up and posttreatment management for these patients is critical. Tumor progression after spine radiosurgery is rare; however, vertebral compression fractures are recognized as a more common posttreatment effect. The use of radiographic imaging alone posttreatment may make it difficult to distinguish tumor progression from postradiation changes such as fibrosis. This is the largest series from a prospective database in which the authors examine histopathology of samples obtained from patients who underwent surgical intervention for presumed tumor progression or mechanical pain secondary to compression fracture. The majority of patients had tumor ablation and resulting fibrosis rather than tumor progression. The aim of this study was to evaluate tumor histopathology and characteristics of patients who underwent pathological sampling because of radiographic tumor progression, fibrosis, or collapsed vertebrae after receiving high-dose single-fraction stereotactic radiosurgery. METHODS Between January 2005 and January 2014, a total of 582 patients were treated with linear accelerator–based single-fraction (18–24 Gy) stereotactic radiosurgery. The authors retrospectively identified 30 patients (5.1%) who underwent surgical intervention for 32 lesions with vertebral cement augmentation for either mechanical pain or instability secondary to vertebral compression fracture (n = 17) or instrumentation (n = 15) for radiographic tumor progression. Radiation and surgical treatment, histopathology, and long-term outcomes were reviewed. Survival and time to recurrence were calculated using the Kaplan-Meier method. RESULTS The mean age at the time of radiosurgery was 59 years (range 36–80 years). The initial pathological diagnoses were obtained for all patients and primarily included radioresistant tumor types, including renal cell carcinoma in 7 (22%), melanoma in 6 (19%), lung carcinoma in 4 (12%), and sarcoma in 3 (9%). The median time to surgical intervention was 24.7 months (range 1.6–50.8 months). The median follow-up and overall survival for all patients were 42.5 months and 41 months (overall survival range 7–86 months), respectively. The majority of assessed lesions showed no evidence of tumor on pathological review (25 of 32, 78%), while a minority of lesions revealed residual tumor (7 of 32, 22%). The median survival for patients after tumor recurrence was 5 months (range 2–70 months). CONCLUSIONS High-dose single-fraction radiosurgery is tumor ablative in the majority of instances. In a minority of cases, tumor persists and salvage treatments should be considered. PMID:28041326

76 FR 68668 - Airworthiness Directives; Fokker Services B.V. Model F.28 Mark 0100 Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-07

... compressive stress during braking at higher deceleration levels outside the regular fatigue load spectrum. [T]he high compressive stress locally exceeds the elasticity limit of the material, leaving a residual tensile stress at release of the heavy braking load. Subsequently, this local residual tensile stress...

Evolution of Residual-Strain Distribution through an Overload-Induced Retardation Period during Fatigue Crack Growth

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

Lee, S. Y.; Sun, Yinan; An, Ke

2010-01-01

Neutron diffraction was employed to investigate the crack-growth retardation phenomenon after a single tensile overload by mapping both one-dimensional and two-dimensional residual-strain distributions around the crack tip in a series of compact-tension specimens representing various crack-growth stages through an overload-induced retardation period. The results clearly show a large compressive residual-strain field near the crack tip immediately after the overload. As the fatigue crack propagates through the overload-induced plastic zone, the compressive residual strains are gradually relaxed, and a new compressive residual-strain field is developed around the propagating crack tip, illustrating that the subsequent fatigue-induced plastic zone grows out of themore » large plastic zone caused by the overloading. The relationship between the overload-induced plastic zone and subsequent fatigue-induced plastic zone, and its influence on the residual-strain distributions in the perturbed plastic zone are discussed.« less

Giant multilevel thoracic hemangioma with spinal cord compression in a patient with Klippel-Weber-Trenaunay syndrome: case report.

PubMed

Grau, Stefan J; Holtmannspoetter, Markus; Seelos, Klaus; Tonn, Joerg-Christian; Siefert, Axel

2009-06-15

Case report and clinical discussion. We intend to report a very rare case of a giant spinal hemangioma causing myelopathy. Multilevel symptomatic spinal hemangiomas causing acute neurologic symptoms are rare disorders. We found only sporadic reports in English literature. We describe a very rare case in which Klippel-Trenaunay-Weber syndrome is associated with a multisegmental vertebral hemangioma causing a rapidly progressing thoracic myelopathy. Because of the extension of the disease, surgical intervention was not feasible, the patient was treated by radiotherapy. The patient showed a complete regression of symptoms with stable condition after 3 months. In extensive spinal hemangiomas, radiotherapy may represent a safe treatment modality with rapid clinical improvement even in cases with spinal cord compression. This report contributes to a wide range of known vascular abnormalities in Klippel-Trenaunay-Weber syndrome and supports the need for a careful multisystemic evaluation of these patients.

Clinical and imaging findings in patients with aggressive spinal hemangioma requiring surgical treatment.

PubMed

Urrutia, Julio; Postigo, Roberto; Larrondo, Roberto; Martin, Aliro San

2011-02-01

Vertebral hemangiomas (VHs) are frequently asymptomatic lesions found incidentally during investigations for other spinal problems. Symptomatic VHs are less common, and there are few reports of compressive VHs in the literature. VHs with aggressive behavior present with low signal intensity on T1-weighted and high signal intensity on T2-weighted MRI. We present a case series of four patients with compressive VH, all of whom were neurologically compromised. Each of the four patients underwent preoperative arterial embolization followed by surgical treatment of their VHs. All patients recovered normal motor function after surgery. At follow-up (average 53 months), one patient had a recurrent tumor requiring reoperation and radiotherapy. Although it is rare, aggressive VH can be a devastating condition. Total surgical resection or subtotal resection with radiotherapy may be warranted. Copyright © 2010 Elsevier Ltd. All rights reserved.

A rare complication of a unilateral vertebral artery occlusion, which resulted in a basilar emboli after a C5-C6 bifacet dislocation in a professional rugby player: case study.

PubMed

Davies, Simon R

2011-03-01

Vertebral artery damage after cervical fracture and especially cervical dislocations is a recognized phenomenon. The incidence of significant intracranial neurology after unilateral vertebral damage is extremely rare, and to our knowledge, no such injury has been sustained while playing sport. To describe a rare vascular complication of a bifacet C5-C6 dislocation. Case report and clinical discussion. We present a 28-year old white man who was a professional rugby player. He sustained a hyperflexion injury while playing scrum half in a recent league match, which resulted in a C5-C6 dislocation, diagnosed clinically and with a plain radiograph. The patient on admission had complete neurologic loss below C6. The patient underwent immediate computed tomography and magnetic resonance imaging (MRI) scans that revealed a 50% displacement of C5 on C6 with a complete unifacet dislocation and the other facet partially dislocated. The MRI revealed signal changes in the cord at the C5-C6 level and an intimal tear in the left vertebral artery. The decision was taken to reduce the dislocation when medically stable. A few hours after injury, after an episode of vomiting, the patient sustained a respiratory arrest owing to the embolization of a clot from the left vertebral artery into the basilar artery. Despite rapid embolectomy and subsequent permanent left vertebral artery occlusion, the patient sustained multiple infarcts in the cerebellar, thalamic, occipital, and pontine regions of the brain that eventually proved fatal. This case shows a rare complication of unilateral vertebral artery occlusion. Despite early identification of a basilar infarct and a successful embolectomy, intracranial infarction occurred. Although there is no guideline for the treatment of vertebral artery damage, early reduction and anticoagulation may reduce the risk of cerebral infarction. Copyright © 2011 Elsevier Inc. All rights reserved.

Embryonic development of the axial column in the little skate, Leucoraja erinacea.

PubMed

Criswell, Katharine E; Coates, Michael I; Gillis, J Andrew

2017-03-01

The morphological patterns and molecular mechanisms of vertebral column development are well understood in bony fishes (osteichthyans). However, vertebral column morphology in elasmobranch chondrichthyans (e.g., sharks and skates) differs from that of osteichthyans, and its development has not been extensively studied. Here, we characterize vertebral development in an elasmobranch fish, the little skate, Leucoraja erinacea, using microCT, paraffin histology, and whole-mount skeletal preparations. Vertebral development begins with the condensation of mesenchyme, first around the notochord, and subsequently around the neural tube and caudal artery and vein. Mesenchyme surrounding the notochord differentiates into a continuous sheath of spindle-shaped cells, which forms the precursor to the mineralized areolar calcification of the centrum. Mesenchyme around the neural tube and caudal artery/vein becomes united by a population of mesenchymal cells that condenses lateral to the sheath of spindle-shaped cells, with this mesenchymal complex eventually differentiating into the hyaline cartilage of the future neural arches, hemal arches, and outer centrum. The initially continuous layers of areolar tissue and outer hyaline cartilage eventually subdivide into discrete centra and arches, with the notochord constricted in the center of each vertebra by a late-forming "inner layer" of hyaline cartilage, and by a ring of areolar calcification located medial to the outer vertebral cartilage. The vertebrae of elasmobranchs are distinct among vertebrates, both in terms of their composition (i.e., with centra consisting of up to three tissues layers-an inner cartilage layer, a calcified areolar ring, and an outer layer of hyaline cartilage), and their mode of development (i.e., the subdivision of arch and outer centrum cartilage from an initially continuous layer of hyaline cartilage). Given the evident variation in patterns of vertebral construction, broad taxon sampling, and comparative developmental analyses are required to understand the diversity of mechanisms at work in the developing axial skeleton of vertebrates. J. Morphol. 278:300-320, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Automated 3D closed surface segmentation: application to vertebral body segmentation in CT images.

PubMed

Liu, Shuang; Xie, Yiting; Reeves, Anthony P

2016-05-01

A fully automated segmentation algorithm, progressive surface resolution (PSR), is presented in this paper to determine the closed surface of approximately convex blob-like structures that are common in biomedical imaging. The PSR algorithm was applied to the cortical surface segmentation of 460 vertebral bodies on 46 low-dose chest CT images, which can be potentially used for automated bone mineral density measurement and compression fracture detection. The target surface is realized by a closed triangular mesh, which thereby guarantees the enclosure. The surface vertices of the triangular mesh representation are constrained along radial trajectories that are uniformly distributed in 3D angle space. The segmentation is accomplished by determining for each radial trajectory the location of its intersection with the target surface. The surface is first initialized based on an input high confidence boundary image and then resolved progressively based on a dynamic attraction map in an order of decreasing degree of evidence regarding the target surface location. For the visual evaluation, the algorithm achieved acceptable segmentation for 99.35 % vertebral bodies. Quantitative evaluation was performed on 46 vertebral bodies and achieved overall mean Dice coefficient of 0.939 (with max [Formula: see text] 0.957, min [Formula: see text] 0.906 and standard deviation [Formula: see text] 0.011) using manual annotations as the ground truth. Both visual and quantitative evaluations demonstrate encouraging performance of the PSR algorithm. This novel surface resolution strategy provides uniform angular resolution for the segmented surface with computation complexity and runtime that are linearly constrained by the total number of vertices of the triangular mesh representation.

Cervical vertebral stenosis associated with a vertebral arch anomaly in the Basset Hound.

PubMed

De Decker, S; De Risio, L; Lowrie, M; Mauler, D; Beltran, E; Giedja, A; Kenny, P J; Gielen, I; Garosi, L; Volk, H

2012-01-01

To report the clinical presentation, imaging characteristics, treatment results, and histopathological findings of a previously undescribed vertebral malformation in the Basset Hound. Retrospective case series study. Eighteen Basset Hounds presented for evaluation of a suspected cervical spinal cord problem. All dogs underwent computed tomography myelography or magnetic resonance imaging of the cervical region. Thirteen male and 5 female Basset Hounds between 6 months and 10.8 years of age (median: 1.4 years) were studied. Clinical signs varied from cervical hyperesthesia to nonambulatory tetraparesis. Imaging demonstrated a well-defined and smooth hypertrophy of the dorsal lamina and spinous process of ≥ 2 adjacent vertebrae. Although this bony abnormality could decrease the ventrodorsal vertebral canal diameter, dorsal midline spinal cord compression was predominantly caused by ligamentum flavum hypertrophy. The articulation between C4 and C5 was most commonly affected. Three dogs were lost to follow-up, 10 dogs underwent dorsal laminectomy, and medical management was initiated in 5 dogs. Surgery resulted in a good outcome with short hospitalization times (median: 4.5 days) in all dogs, whereas medical management produced more variable results. Histopathology confirmed ligamentum flavum hypertrophy and demonstrated the fibrocartilaginous nature of this anomaly. Dorsal lamina and spinous process hypertrophy leading to ligamentum flavum hypertrophy should be included in the differential diagnosis of Basset Hounds with cervical hyperesthesia or myelopathy. Prognosis after decompressive surgery is favorable. Although a genetic component is suspected, additional studies are needed to determine the specific etiology of this disorder. Copyright © 2012 by the American College of Veterinary Internal Medicine.

Single balloon versus double balloon bipedicular kyphoplasty: a systematic review and meta-analysis.

PubMed

Jing, Zehao; Dong, Jianli; Li, Zhengwei; Nan, Feng

2018-06-19

Kyphoplasty has been widely used to treat vertebral compression fractures (VCFs). In standard procedure of kyphoplasty, two balloons were inserted into the vertebral body through bipedicular and inflated simultaneously, while using a single balloon two times is also a common method in clinic to lessen the financial burden of patients. However, the effect and safety of single balloon versus double balloon bipedicular kyphoplasty are still controversy. In this systematic review and meta-analysis, eligible studies were identified through a comprehensive literature search of PubMed, Cochrane library EMBASE, Web of Science, Wanfang, CNKI, VIP and CBM until January 1, 2018. Results from individual studies were pooled using a random or fixed effects model. Seven articles were included in the systematic review and five studies were consisted in meta-analysis. We observed no significant difference between single balloon and double balloon bipedicular kyphoplasty in visual analog scale (VAS), angle (kyphotic angle and Cobb angle), consumption (operation time, cement volume and volume of bleeding), vertebral height (anterior height, medium height and posterior height) and complications (cement leakage and new VCFs), while the cost of single balloon bipedicular kyphoplasty is lower than that of double balloon bipedicular kyphoplasty. The results of our meta-analysis also demonstrated that single balloon can significantly improve the VAS, angle and vertebral height of patients suffering from VCFs. This systematic review and meta-analysis collectively concludes that single balloon bipedicular kyphoplasty is as effective as double balloon bipedicular kyphoplasty in improving clinical symptoms, deformity and complications of VCFs but not so expensive. These slides can be retrieved under Electronic Supplementary Material.

Effect of teriparatide on pregnancy and lactation-associated osteoporosis with multiple vertebral fractures.

PubMed

Choe, Eun Yeong; Song, Je Eun; Park, Kyeong Hye; Seok, Hannah; Lee, Eun Jig; Lim, Sung-Kil; Rhee, Yumie

2012-09-01

Pregnancy and lactation-associated osteoporosis (PLO) is very rare, but it can cause severe vertebral compression fractures with disabling back pain. PLO patients have commonly been treated with antiresorptive agents against high bone turnover. There are, however, some concerns regarding the use of bisphosphonates: (1) PLO occurs during the first pregnancy with a high possibility of recurrence during the second pregnancy, (2) long-term outcomes of bisphosphonates in PLO are lacking, and (3) there is a possibility of bisphosphonates accumulated in the bones crossing the placenta. Therefore, alternative therapies must be considered. We analyzed the effect of teriparatide (TPTD), the human recombinant parathyroid hormone (1-34), for 18 months in three women with PLO. Multiple vertebral fractures with severe back pain appeared within 6 months after their first childbirth. Two of them had a family history of osteoporosis. Lactation was discontinued immediately after diagnosis of PLO. Calcium carbonate, cholecalciferol, and TPTD were prescribed. The back pain immediately resolved. Bone mineral density (BMD) increased by 14.5-25.0% (mean 19.5%) at the lumbar spine and by 9.5-16.7% (mean 13.1%) at the femoral neck, after 18 months of treatment. The final Z scores in these PLO patients were nearly normalized. Two women had a second baby without any complication. BMD significantly improved after 18 months of treatment with TPTD without further fractures. In conclusion, TPTD should be considered to avoid long-term morbidity in young patients with PLO and is highly encouraged for use in PLO patients with multiple vertebral fractures.

Accessing Forbidden Glass Regimes through High-Pressure Sub-Tg Annealing

PubMed Central

Svenson, Mouritz N.; Mauro, John C.; Rzoska, Sylwester J.; Bockowski, Michal; Smedskjaer, Morten M.

2017-01-01

Density and hardness of glasses are known to increase upon both compression at the glass transition temperature (Tg) and ambient pressure sub-Tg annealing. However, a serial combination of the two methods does not result in higher density and hardness, since the effect of compression is countered by subsequent annealing and vice versa. In this study, we circumvent this by introducing a novel treatment protocol that enables the preparation of high-density, high-hardness bulk aluminosilicate glasses. This is done by first compressing a sodium-magnesium aluminosilicate glass at 1 GPa at Tg, followed by sub-Tg annealing in-situ at 1 GPa. Through density, hardness, and heat capacity measurements, we demonstrate that the effects of hot compression and sub-Tg annealing can be combined to access a “forbidden glass” regime that is inaccessible through thermal history or pressure history variation alone. We also study the relaxation behavior of the densified samples during subsequent ambient pressure sub-Tg annealing. Density and hardness are found to relax and approach their ambient condition values upon annealing, but the difference in relaxation time of density and hardness, which is usually observed for hot compressed glasses, vanishes for samples previously subjected to high-pressure sub-Tg annealing. This confirms the unique configurational state of these glasses. PMID:28418017

Numerical assessment of the role of slip and twinning in magnesium alloy AZ31B during loading path reversal

DOE PAGES

Wang, Huamiao; Wu, Peidong; Wang, Jian

2015-04-17

Magnesium alloy AZ31B plastically deforms via twinning and slip. Corresponding to the unidirectional nature of twinning, the activity of twinning/detwinning is directly related to loading history and materials texture. Using the elastic viscoplastic self-consistent model implementing with the twinning and detwinning model (EVPSC–TDT), we revisited experimental data of AZ31B sheets under four different strain paths: (1) tension–compression–tension along rolling direction, (2) tension–compression–tension along transverse direction, (3) compression–tension–compression along rolling direction, and (4) compression–tension–compression along transverse direction, and identified the dominant deformation mechanisms with respect to the strain path. We captured plastic deformation behaviors observed in experiments and quantitatively interpreted experimentalmore » observations in terms of the activities of different deformation mechanisms and the evolution of texture. It is found that the in-plane pre-tension has slight effect on the subsequent deformation, and the pre-compression and the reverse tension after compression have significant effect on the subsequent deformation. The inelastic behavior under compressive unloading is found to be insignificant at a small strain level but pronounced at a large strain level. Lastly, such significant effect is mainly ascribed to the activity of twinning and detwinning.« less

Characterization and expression of amphioxus ApoD gene encoding an archetype of vertebrate ApoD proteins.

PubMed

Wang, Lei; Zhang, Shicui; Liu, Zhenhui; Li, Hongyan; Wang, Yongjun; Jiang, Shengjuan

2007-01-01

Here we report a homologue of the apolipoprotein D gene (AmphiApoD) in amphioxus, Branchiostoma belcheri tsingtauense, the first such finding in a basal chordate cephalochordate. The main features of the protein predicted from AmphiApoD are characteristic of the apolipoprotein D. Phylogenetic analysis places AmphiApoD at the base of the phylogenetic tree, suggesting that AmphiApoD is the archetype of the vertebrate ApoD genes. Both whole mount in situ hybridization and Northern blotting and RT-PCR as well as in situ hybridization histochemistry reveal that AmphiApoD is expressed in tissues derived from mesoderm and endoderm including notochord and hind-gut, which contrasts with the strong expression patterns of ApoD genes in the ectodermal derivatives in mammals and birds. The expression profiles of the ApoD gene may have been changed to be expressed in the endo-mesodermal derivatives in amphioxus after the vertebrate and cephalochordate lineages diverged; alternatively, the ApoD gene may first have been expressed in the endo-mesoderm during embryogenesis in the last common ancestor of all chordates, and subsequently came to be expressed in the ectodermal derivatives of vertebrates including mammals and birds.

The ocular skeleton through the eye of evo-devo.

PubMed

Franz-Odendaal, Tamara Anne

2011-09-15

An evolutionary developmental (evo-devo) approach to understanding the evolution, homology, and development of structures has proved important for unraveling complex integrated skeletal systems through the use of modules, or modularity. An ocular skeleton, which consists of cartilage and sometimes bone, is present in many vertebrates; however, the origin of these two components remains elusive. Using both paleontological and developmental data, I propose that the vertebrate ocular skeleton is neural crest derived and that a single cranial neural crest module divided early in vertebrate evolution, possibly during the Ordovician, to give rise to an endoskeletal component and an exoskeletal component within the eye. These two components subsequently became uncoupled with respect to timing, placement within the sclera and inductive epithelia, enabling them to evolve independently and to diversify. In some extant groups, these two modules have become reassociated with one another. Furthermore, the data suggest that the endoskeletal component of the ocular skeleton was likely established and therefore evolved before the exoskeletal component. This study provides important insights into the evolution of the ocular skeleton, a region with a long evolutionary history among vertebrates. Copyright © 2011 Wiley-Liss, Inc., A Wiley Company.

Insulin-like growth factor I: a biologic maturation indicator.

PubMed

Ishaq, Ramy Abdul Rahman; Soliman, Sanaa Abou Zeid; Foda, Manal Yehya; Fayed, Mona Mohamed Salah

2012-11-01

Determination of the maturation level and the subsequent evaluation of growth potential during preadolescence and adolescence are important for optimal orthodontic treatment planning and timing. This study was undertaken to evaluate the applicability of insulin-like growth factor I (IGF-I) blood level as a maturation indicator by correlating it to the cervical vertebral maturation index. The study was conducted with 120 subjects, equally divided into 60 males (ages, 10-18 years) and 60 females (ages, 8-16 years). A lateral cephalometric radiograph and a blood sample were taken from each subject. For each subject, cervical vertebral maturation and IGF-I serum level were assessed. Mean values of IGF-I in each stage of cervical vertebral maturation were calculated, and the means in each stage were statistically compared with those of the other stages. The IGF-I mean value at each cervical vertebral maturation stage was statistically different from the mean values at the other stages. The highest mean values were observed in stage 4, followed by stage 5 in males and stage 3 in females. IGF-I serum level is a reliable maturation indicator that could be applied in orthodontic diagnosis. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

An antiarch placoderm shows that pelvic girdles arose at the root of jawed vertebrates

PubMed Central

Zhu, Min; Yu, Xiaobo; Choo, Brian; Wang, Junqing; Jia, Liantao

2012-01-01

Almost all gnathostomes or jawed vertebrates (including osteichthyans, chondrichthyans, ‘acanthodians’ and most placoderms) possess paired pectoral and pelvic fins. To date, it has generally been believed that antiarch placoderms (extinct armoured jawed fishes from the Silurian–Devonian periods) lacked pelvic fins. The putative absence of pelvic fins is a key character bearing on the monophyly or paraphyly of placoderms. It also has far-reaching implications for studying the sequence of origin of pelvic girdles versus that of movable jaws in the course of vertebrate evolution. Parayunnanolepis xitunensis represents the only example of a primitive antiarch with extensive post-thoracic preservation, and its original description has been cited as confirming the primitive lack of pelvic fins in early antiarchs. Here, we present a revised description of Parayunnanolepis and offer the first unambiguous evidence for the presence of pelvic girdles in antiarchs. As antiarchs are placed at the base of the gnathostome radiation in several recent studies, our finding shows that all jawed vertebrates (including antiarch placoderms) primitively possess both pectoral and pelvic fins and that the pelvic fins did not arise within gnathostomes at a point subsequent to the origin of jaws. PMID:22219394

Aggressive hemangioma of the thoracic spine.

PubMed

Schrock, Wesley B; Wetzel, Raun J; Tanner, Stephanie C; Khan, Majid A

2011-01-01

Vertebral hemangiomas are common lesions and usually considered benign. A rare subset of them, however, are characterized by extra-osseous extension, bone expansion, disturbance of blood flow, and occasionally compression fractures and thereby referred to as aggressive hemangiomas. We present a case of a 67-year-old woman with progressive paraplegia and an infiltrative mass of T4 vertebra causing mass effect on the spinal cord. Multiple conventional imaging modalities were utilized to suggest the diagnosis of aggressive hemangioma. Final pathologic diagnosis after decompressive surgery confirmed the diagnosis of an osseous hemangioma.

Aggressive hemangioma of the thoracic spine

PubMed Central

Schrock, Wesley B.; Wetzel, Raun J.; Tanner, Stephanie C.; Khan, Majid A.

2011-01-01

Vertebral hemangiomas are common lesions and usually considered benign. A rare subset of them, however, are characterized by extra-osseous extension, bone expansion, disturbance of blood flow, and occasionally compression fractures and thereby referred to as aggressive hemangiomas. We present a case of a 67-year-old woman with progressive paraplegia and an infiltrative mass of T4 vertebra causing mass effect on the spinal cord. Multiple conventional imaging modalities were utilized to suggest the diagnosis of aggressive hemangioma. Final pathologic diagnosis after decompressive surgery confirmed the diagnosis of an osseous hemangioma. PMID:22470764

Candida albicans osteomyelitis of the spine: progressive clinical and radiological features and surgical management in three cases.

PubMed

Khazim, Rabi M; Debnath, Ujjwal K; Fares, Youssef

2006-09-01

Candida albicans vertebral osteomyelitis is rare. Three cases are presented. Without antifungal treatment, they developed spinal collapse and neurological deterioration within 3-6 months from the onset of symptoms. There was a delay of 4.5 and 7.5 months between the onset of symptoms and surgery. All patients were managed with surgical debridement and reconstruction and 12-week fluconazole treatment. The neurological deficits resolved completely. The infection has not recurred clinically or radiologically at 5-6 years follow-up. Although rare, Candida should be suspected as a causative pathogen in cases of spinal osteomyelitis. Without treatment the disease is progressive. As soon as osteomyelitis is suspected, investigations with MRI and percutaneous biopsy should be performed followed by medical therapy. This may prevent the need for surgery. However, if vertebral collapse and spinal cord compression occurs, surgical debridement, fusion and stabilisation combined with antifungal medications can successfully eradicate the infection and resolve the neurological deficits.

Candida albicans osteomyelitis of the spine: progressive clinical and radiological features and surgical management in three cases

PubMed Central

Debnath, Ujjwal K; Fares, Youssef

2006-01-01

Candida albicans vertebral osteomyelitis is rare. Three cases are presented. Without antifungal treatment, they developed spinal collapse and neurological deterioration within 3–6 months from the onset of symptoms. There was a delay of 4.5 and 7.5 months between the onset of symptoms and surgery. All patients were managed with surgical debridement and reconstruction and 12-week fluconazole treatment. The neurological deficits resolved completely. The infection has not recurred clinically or radiologically at 5–6 years follow-up. Although rare, Candida should be suspected as a causative pathogen in cases of spinal osteomyelitis. Without treatment the disease is progressive. As soon as osteomyelitis is suspected, investigations with MRI and percutaneous biopsy should be performed followed by medical therapy. This may prevent the need for surgery. However, if vertebral collapse and spinal cord compression occurs, surgical debridement, fusion and stabilisation combined with antifungal medications can successfully eradicate the infection and resolve the neurological deficits. PMID:16429290

Lumbar vertebral hemangioma mimicking lateral spinal canal stenosis: case report and review of literature.

PubMed

Syrimpeis, Vasileios; Vitsas, Vasileios; Korovessis, Panagiotis

2014-03-01

Context Hemangiomas are the commonest benign tumors of the spine. Most occur in the thoracolumbar spine and the majority are asymptomatic. Rarely, hemangiomas cause symptoms through epidural expansion of the involved vertebra, resulting in spinal canal stenosis, spontaneous epidural hemorrhage, and pathological burst fracture. Findings We report a rare case of a 73-year-old woman, who had been treated for two months for degenerative neurogenic claudication. On admission, magnetic resonance imaging and computed tomographic scans revealed a hemangioma of the third lumbar vertebra protruding to the epidural space producing lateral spinal stenosis and ipsilateral nerve root compression. The patient underwent successful right hemilaminectomy for decompression of the nerve root, balloon kyphoplasty with poly-methyl methacrylate (PMMA) and pedicle screw segmental stabilization. Postoperative course was uneventful. Conclusion In the elderly, this rare presentation of spinal stenosis due to hemangiomas may be encountered. Decompression and vertebral augmentation by means balloon kyphoplasty with PMMA plus segmental pedicle screw fixation is recommended.

Lumbar vertebral hemangioma mimicking lateral spinal canal stenosis: Case report and review of literature

PubMed Central

Syrimpeis, Vasileios; Vitsas, Vasileios; Korovessis, Panagiotis

2014-01-01

Context Hemangiomas are the commonest benign tumors of the spine. Most occur in the thoracolumbar spine and the majority are asymptomatic. Rarely, hemangiomas cause symptoms through epidural expansion of the involved vertebra, resulting in spinal canal stenosis, spontaneous epidural hemorrhage, and pathological burst fracture. Findings We report a rare case of a 73-year-old woman, who had been treated for two months for degenerative neurogenic claudication. On admission, magnetic resonance imaging and computed tomographic scans revealed a hemangioma of the third lumbar vertebra protruding to the epidural space producing lateral spinal stenosis and ipsilateral nerve root compression. The patient underwent successful right hemilaminectomy for decompression of the nerve root, balloon kyphoplasty with poly-methyl methacrylate (PMMA) and pedicle screw segmental stabilization. Postoperative course was uneventful. Conclusion In the elderly, this rare presentation of spinal stenosis due to hemangiomas may be encountered. Decompression and vertebral augmentation by means balloon kyphoplasty with PMMA plus segmental pedicle screw fixation is recommended. PMID:24090267

Pregnancy-associated osteoporosis presenting severe vertebral fractures.

PubMed

Ozturk, Cihat; Atamaz, Funda Calis; Akkurt, Halil; Akkoc, Yesim

2014-01-01

The syndrome of pregnancy-associated osteoporosis (PAO) is a rare disorder which occurs either in late pregnancy or early post-partum period leading to fragility fracture(s), most commonly in the vertebral bodies. We presented two cases with PAO who had compression fractures at multiple levels involving five vertebrae in one case and 10 vertebrae in the other. Their spinal bone mineral density values were below -2.5 standard deviations. Anti-osteoporotic treatments with nasal calcitonin 400 IU/day, vitamin D 300.000 IU single dose, calcium 1000 mg/day, vitamin D 880 IU/day were initiated. In one case, kyphoplasty was performed by a spinal surgeon. In addition to a thoracolumbosacral orthosis, a rehabilitation program including muscle strengthening, range of motion, relaxation and weight-bearing exercises was started for both cases. These cases emphasize that all pregnant women with complaints of back/lumbar pain should be carefully evaluated. © 2013 The Authors. Journal of Obstetrics and Gynaecology Research © 2013 Japan Society of Obstetrics and Gynecology.

Soliton compression to few-cycle pulses with a high quality factor by engineering cascaded quadratic nonlinearities.

PubMed

Zeng, Xianglong; Guo, Hairun; Zhou, Binbin; Bache, Morten

2012-11-19

We propose an efficient approach to improve few-cycle soliton compression with cascaded quadratic nonlinearities by using an engineered multi-section structure of the nonlinear crystal. By exploiting engineering of the cascaded quadratic nonlinearities, in each section soliton compression with a low effective order is realized, and high-quality few-cycle pulses with large compression factors are feasible. Each subsequent section is designed so that the compressed pulse exiting the previous section experiences an overall effective self-defocusing cubic nonlinearity corresponding to a modest soliton order, which is kept larger than unity to ensure further compression. This is done by increasing the cascaded quadratic nonlinearity in the new section with an engineered reduced residual phase mismatch. The low soliton orders in each section ensure excellent pulse quality and high efficiency. Numerical results show that compressed pulses with less than three-cycle duration can be achieved even when the compression factor is very large, and in contrast to standard soliton compression, these compressed pulses have minimal pedestal and high quality factor.

Bone cement distribution is a potential predictor to the reconstructive effects of unilateral percutaneous kyphoplasty in OVCFs: a retrospective study.

PubMed

Lin, Jiachen; Qian, Lie; Jiang, Changqing; Chen, Xiuyuan; Feng, Fan; Lao, Lifeng

2018-06-07

Osteoporotic vertebral compression fracture (OVCF) is a common type of fracture, and percutaneous kyphoplasty (PKP) is an eligible solution to it. Previous studies have revealed that both the volume and filling pattern of bone cement correlate with the clinical outcomes after PKP procedure. However, the role of bone cement distribution remains to be illustrated. To retrospectively evaluate the relationship between the bone cement distribution and the clinical outcomes of unilateral PKP, we enrolled 73 OVCF patients receiving unilateral PKP treatment. All the intervened vertebrae were classified into three groups based on the bone cement distribution observed on postoperative X-ray films. Preoperative and postoperative radiographic parameters including the vertebral height and kyphotic Cobb angle were recorded, and anterior vertebral height restoration rate (AVHRR) and Cobb angle correction (CR) were then calculated to assess the vertebral height reconstruction. Preoperative and postoperative Oswestry Disability Index (ODI) and visual analogue scale (VAS) were adopted by interviewing patients to assess the mobility improvement and pain relief. Demographic data, body mass index (BMI), lumbar bone mineral density (evaluated by BMD T-score) of each patient, bone cement volume (BV), and bone cement extravasation (BE) were also recorded. Between- and within-group comparisons and multivariable correlation analysis were carried out to analyze the data. VAS and ODI scores were both significantly improved in all of the enrolled cases with no significant differences between groups. Among the three groups, the average age, AVHRR, and BV were significantly different. Occurrence of BE was significantly different between two of the three groups. AVHRR was demonstrated to correlate negatively with preoperative anterior vertebral height ratio and positively with preoperative Cobb angle, CR, diffusion score, and ODI changes. Bone cement distribution is a potential predictor to the reconstructive effects in unilateral PKP for OVCFs. Bone cement distribution is associated with AVHRR and BV, as well as the risk of BE occurrence. Greater bone cement distribution may indicate better vertebral restoration along with a higher BE risk.

Compression Ratio Ion Mobility Programming (CRIMP) Accumulation and Compression of Billions of Ions for Ion Mobility-Mass Spectrometry Using Traveling Waves in Structures for Lossless Ion Manipulations (SLIM)

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

Deng, Liulin; Garimella, Sandilya V. B.; Hamid, Ahmed M.

We report on the implementation of a traveling wave (TW) based compression ratio ion mobility programming (CRIMP) approach within Structures for Lossless Ion Manipulations (SLIM) that enables both greatly enlarged trapped ion charge capacities and also their subsequent efficient compression for use in ion mobility (IM) separations. Ion accumulation is conducted in a long serpentine path TW SLIM region after which CRIMP allows the large ion populations to be ‘squeezed’. The compression process occurs at an interface between two SLIM regions, one operating conventionally and the second having an intermittently pausing or ‘stuttering’ TW, allowing the contents of multiple binsmore » of ions from the first region to be merged into a single bin in the second region. In this initial work stationary voltages in the second region were used to block ions from exiting the first (trapping) region, and the resumption of TWs in the second region allows ions to exit, and the population to also be compressed if CRIMP is applied. In our initial evaluation we show that the number of charges trapped for a 40 s accumulation period was ~5×109, more than two orders of magnitude greater than the previously reported charge capacity using an ion funnel trap. We also show that over 1×109 ions can be accumulated with high efficiency in the present device, and that the extent of subsequent compression is only limited by the space charge capacity of the trapping region. Lower compression ratios allow increased IM peak heights without significant loss of signal, while excessively large compression ratios can lead to ion losses and other artifacts. Importantly, we show that extended ion accumulation in conjunction with CRIMP and multiple passes provides the basis for a highly desirable combination of ultra-high sensitivity and ultra-high resolution IM separations using SLIM.« less

Vertebral osteoporosis: perfused animal cadaver model for testing new vertebroplastic agents.

PubMed

Hoell, Thomas; Huschak, Gerald; Beier, Andre; Holzhausen, Hans-Juergen; Meisel, Hans-Joerg; Emmrich, Frank

2010-12-01

Experimental study. It was aimed to establish a cadaver model to imitate osteoporotic perfused vertebral bone and to allow for transpedicular transfer of bone cement and various new materials into vertebrae. The model was perfused to simulate vertebroplasty in the presence of transvertebral blood flow. The injection of bone cement into vertebrae bears the risk of irreversible discharge of material into the venous system of the spinal canal. The bovine cadaver model studied allows visual studies of material distribution in a vertebral bone, the potential spill-out of material, and quantification of washout and disintegration phenomena. Thoracic and lumbar vertebrae from 1-year-old calves were cut transversally into 5 mm slices, macerated, and decalcified. The softened bone slices were compressed between 2 transparent plastic discs. A standard vertebroplasty cannula (outer diameter 3.5 mm, inner diameter 2.5 mm) was inserted into the vertebral body via the pedicle to transfer the different vertebroplasty materials. Arterial blood flow was simulated by means of liquid irrigation via 2 needles in the ventral part of the vertebral body slice. Metal powder was mixed with the solution to indicate the blood flow in the bone. The model was evaluated with the vertebroplasty cement polymethylmethacrylate. The model permitted visualization of the insertion and distribution of vertebroplasty materials. Liquid bone cement was effused into the spinal canal as in the clinical situation. Higher modulus cement acted in the same way as in clinical vertebroplasty. Rigid vertebroplasty agents led to trabecular fractures and stable mechanical interactions with the bone and eventually moved dorsal bone fragments into the spinal canal. Sedimentation of the metal powder indicated regions of perfusion. The model simulated the clinical behavior of liquid and higher modulus vertebroplasty agents in the presence of blood flow. It enabled safe ex vivo testing of the mechanical and physical properties of alternative vertebroplasty materials under flow conditions.

Loss of Type I Collagen Telopeptide Lysyl Hydroxylation Causes Musculoskeletal Abnormalities in a Zebrafish Model of Bruck Syndrome.

PubMed

Gistelinck, Charlotte; Witten, Paul Eckhard; Huysseune, Ann; Symoens, Sofie; Malfait, Fransiska; Larionova, Daria; Simoens, Pascal; Dierick, Manuel; Van Hoorebeke, Luc; De Paepe, Anne; Kwon, Ronald Y; Weis, MaryAnn; Eyre, David R; Willaert, Andy; Coucke, Paul J

2016-11-01

Bruck syndrome (BS) is a disorder characterized by joint flexion contractures and skeletal dysplasia that shows strong clinical overlap with the brittle bone disease osteogenesis imperfecta (OI). BS is caused by biallelic mutations in either the FKBP10 or the PLOD2 gene. PLOD2 encodes the lysyl hydroxylase 2 (LH2) enzyme, which is responsible for the hydroxylation of lysine residues in fibrillar collagen telopeptides. This hydroxylation directs crosslinking of collagen fibrils in the extracellular matrix, which is necessary to provide stability and tensile integrity to the collagen fibrils. To further elucidate the function of LH2 in vertebrate skeletal development, we created a zebrafish model harboring a homozygous plod2 nonsense mutation resulting in reduced telopeptide hydroxylation and crosslinking of bone type I collagen. Adult plod2 mutants present with a shortened body axis and severe skeletal abnormalities with evidence of bone fragility and fractures. The vertebral column of plod2 mutants is short and scoliotic with compressed vertebrae that show excessive bone formation at the vertebral end plates, and increased tissue mineral density in the vertebral centra. The muscle fibers of mutant zebrafish have a reduced diameter near the horizontal myoseptum. The endomysium, a layer of connective tissue ensheathing the individual muscle fibers, is enlarged. Transmission electron microscopy of mutant vertebral bone shows type I collagen fibrils that are less organized with loss of the typical plywood-like structure. In conclusion, plod2 mutant zebrafish show molecular and tissue abnormalities in the musculoskeletal system that are concordant with clinical findings in BS patients. Therefore, the plod2 zebrafish mutant is a promising model for the elucidation of the underlying pathogenetic mechanisms leading to BS and the development of novel therapeutic avenues in this syndrome. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and Mineral Research.

The remnant of the European rabbit (Oryctolagus cuniculus) IgD gene

PubMed Central

Esteves, Pedro J.; Knight, Katherine L.

2017-01-01

Although IgD first appeared, along with IgM, in the cartilaginous fishes and has been retained throughout subsequent vertebrate evolution, it has been lost in a diverse group of vertebrate species. We previously showed that, unlike vertebrates that express IgD, the rabbit lacks an IgD (Cδ) gene within 13.5 kb downstream of the IgM gene. We report here that, by conducting BLAST searches of rabbit Ig heavy chain genomic DNA with known mammalian IgD exons, we identified the remnant of the rabbit Cδ gene approximately 21 kb downstream of the IgM gene. The remnant Cδ locus lacks the δCH1 and hinge exons, but contains truncated δCH2 and δCH3 exons, as well as largely intact, but non-functional, secretory and transmembrane exons. In addition, we report that the Cδ gene probably became non-functional in leporids at least prior to the divergence of rabbits and hares ~12 million years ago. PMID:28832642

Compression and contact area of anterior strut grafts in spinal instrumentation: a biomechanical study.

PubMed

Pizanis, Antonius; Holstein, Jörg H; Vossen, Felix; Burkhardt, Markus; Pohlemann, Tim

2013-08-26

Anterior bone grafts are used as struts to reconstruct the anterior column of the spine in kyphosis or following injury. An incomplete fusion can lead to later correction losses and compromise further healing. Despite the different stabilizing techniques that have evolved, from posterior or anterior fixating implants to combined anterior/posterior instrumentation, graft pseudarthrosis rates remain an important concern. Furthermore, the need for additional anterior implant fixation is still controversial. In this bench-top study, we focused on the graft-bone interface under various conditions, using two simulated spinal injury models and common surgical fixation techniques to investigate the effect of implant-mediated compression and contact on the anterior graft. Calf spines were stabilised with posterior internal fixators. The wooden blocks as substitutes for strut grafts were impacted using a "pressfit" technique and pressure-sensitive films placed at the interface between the vertebral bone and the graft to record the compression force and the contact area with various stabilization techniques. Compression was achieved either with posterior internal fixator alone or with an additional anterior implant. The importance of concomitant ligament damage was also considered using two simulated injury models: pure compression Magerl/AO fracture type A or rotation/translation fracture type C models. In type A injury models, 1 mm-oversized grafts for impaction grafting provided good compression and fair contact areas that were both markedly increased by the use of additional compressing anterior rods or by shortening the posterior fixator construct. Anterior instrumentation by itself had similar effects. For type C injuries, dramatic differences were observed between the techniques, as there was a net decrease in compression and an inadequate contact on the graft occurred in this model. Under these circumstances, both compression and the contact area on graft could only be maintained at high levels with the use of additional anterior rods. Under experimental conditions, we observed that ligamentous injury following type C fracture has a negative influence on the compression and contact area of anterior interbody bone grafts when only an internal fixator is used for stabilization. Because of the loss of tension banding effects in type C injuries, an additional anterior compressing implant can be beneficial to restore both compression to and contact on the strut graft.

Posterior inferior cerebellar artery to posterior inferior cerebellar artery in situ bypass for the treatment of Bow hunter's-type dynamic ischemia in holovertebral dissection.

PubMed

Kan, Peter; Yashar, Parham; Langer, David J; Siddiqui, Adnan H; Levy, Elad I

2012-11-01

Bow hunter's syndrome is a rare cause of vertebrobasilar insufficiency arising from mechanical compression of the vertebral artery (VA) during rotation of the head. Surgical treatment usually involves direct decompression of the VA at the site of compression. We describe what is to our knowledge the first reported case of a posterior inferior cerebellar artery (PICA)-to-PICA in situ bypass for treatment of Bow hunter's-type ischemia in a patient with a VA dissection. The patient was a 41-year-old man who developed disabling symptoms of vertebrobasilar insufficiency after trauma when he rotated his head to the right. Dynamic angiography demonstrated a chronic dissection and stasis of flow in the right VA when his head was rotated to the right, with no obvious site of focal compression. The right VA ended in the PICA and the left VA was of good caliber. A single-photon emission computed tomography study with acetazolamide challenge confirmed brainstem ischemia and poor cerebrovascular reserve. He ultimately underwent a PICA-to-PICA in situ bypass to revascularize his right PICA territory with complete symptom resolution. The PICA-to-PICA in situ bypass is a useful option in the treatment of Bow hunter's-type ischemia in the absence of focal structural compression of the VA or VA stenosis. Copyright © 2012 Elsevier Inc. All rights reserved.

Promoting Interactive Learning: A Classroom Exercise to Explore Foraging Strategies

ERIC Educational Resources Information Center

Beaumont, Ellen S.; Rowe, Graham; Mikhaylov, Natalie S.

2012-01-01

We describe a classroom exercise to allow students to explore foraging strategies in higher vertebrates. The exercise includes an initial interactive session in which students act as predators and are guided through foraging simulations, and a subsequent student-led session where classmates are employed as experimental subjects. Students rated the…

The vertebrate ancestral repertoire of visual opsins, transducin alpha subunits and oxytocin/vasopressin receptors was established by duplication of their shared genomic region in the two rounds of early vertebrate genome duplications.

PubMed

Lagman, David; Ocampo Daza, Daniel; Widmark, Jenny; Abalo, Xesús M; Sundström, Görel; Larhammar, Dan

2013-11-02

Vertebrate color vision is dependent on four major color opsin subtypes: RH2 (green opsin), SWS1 (ultraviolet opsin), SWS2 (blue opsin), and LWS (red opsin). Together with the dim-light receptor rhodopsin (RH1), these form the family of vertebrate visual opsins. Vertebrate genomes contain many multi-membered gene families that can largely be explained by the two rounds of whole genome duplication (WGD) in the vertebrate ancestor (2R) followed by a third round in the teleost ancestor (3R). Related chromosome regions resulting from WGD or block duplications are said to form a paralogon. We describe here a paralogon containing the genes for visual opsins, the G-protein alpha subunit families for transducin (GNAT) and adenylyl cyclase inhibition (GNAI), the oxytocin and vasopressin receptors (OT/VP-R), and the L-type voltage-gated calcium channels (CACNA1-L). Sequence-based phylogenies and analyses of conserved synteny show that the above-mentioned gene families, and many neighboring gene families, expanded in the early vertebrate WGDs. This allows us to deduce the following evolutionary scenario: The vertebrate ancestor had a chromosome containing the genes for two visual opsins, one GNAT, one GNAI, two OT/VP-Rs and one CACNA1-L gene. This chromosome was quadrupled in 2R. Subsequent gene losses resulted in a set of five visual opsin genes, three GNAT and GNAI genes, six OT/VP-R genes and four CACNA1-L genes. These regions were duplicated again in 3R resulting in additional teleost genes for some of the families. Major chromosomal rearrangements have taken place in the teleost genomes. By comparison with the corresponding chromosomal regions in the spotted gar, which diverged prior to 3R, we could time these rearrangements to post-3R. We present an extensive analysis of the paralogon housing the visual opsin, GNAT and GNAI, OT/VP-R, and CACNA1-L gene families. The combined data imply that the early vertebrate WGD events contributed to the evolution of vision and the other neuronal and neuroendocrine functions exerted by the proteins encoded by these gene families. In pouched lamprey all five visual opsin genes have previously been identified, suggesting that lampreys diverged from the jawed vertebrates after 2R.

Malignant pheochromocytoma with multiple vertebral metastases causing acute incomplete paralysis during pregnancy

PubMed Central

Liu, Shuzhong; Song, An; Zhou, Xi; Kong, Xiangyi; Li, William A.; Wang, Yipeng; Liu, Yong

2017-01-01

Abstract Rationale: We present a rare case of malignant pheochromocytoma with thoracic metastases during pregnancy that presented with symptoms of myelopathy and was treated with circumferential decompression, stabilization, and radiation. The management of this unique case is not well documented. The clinical manifestations, imaging results, pathological characteristics, treatment and prognosis of the case were analyzed. Patient concerns: A 26-year-old pregnant woman with a history of paroxysmal hypertension during the second trimester presented with lower extremity weakness, numbness, urinary incontinence, and back pain. Imaging studies revealed a right adrenal pheochromocytoma, multiple metastases at T8, T11, T12, and the pelvis girdle causing significant multilevel cord compression and significant osteolytic lesions at T11 and T12. Diagnoses: We believe this is the first reported case of metastatic pheochromocytoma of the thoracic spine presenting with symptoms of myelopathy during pregnancy. Interventions: A healthy neonate was delivered by emergency caesarean section at 34 weeks. Subsequently, the patient underwent a circumferential spinal cord decompression and a stabilization procedure. Outcomes: The patient's neurological deficits improved significantly after the surgery, and the postoperative period was uneventful at the 6-month follow-up visit. Lessons: This article emphasizes that metastatic pheochromocytoma of the spine, although rare, should be part of the differential when a patient presents with elevated blood pressure, weakness, and urinary incontinence. PMID:29095319

Moderate-intensity running causes intervertebral disc compression in young adults.

PubMed

Kingsley, Michael Ian; D'Silva, Lindsay Antonio; Jennings, Cameron; Humphries, Brendan; Dalbo, Vincent James; Scanlan, Aaron Terrance

2012-11-01

Decreased intervertebral disc (IVD) volume can result in diminished load-carrying capacity of the spinal region. Although moderate-intensity running is generally advocated for apparently healthy adults, running causes a loss in stature that is thought to reflect IVD compression. The aim of this investigation was to use magnetic resonance imaging (MRI) to quantify the influence of moderate-intensity treadmill running on IVD height and volume in the thoracic and lumbar regions of the vertebral column. A clinic-based repeated-measures design was used in eight healthy young asymptomatic adults. After preliminary measurements and familiarization (day 1), participants reported to the clinic on two further occasions. MRI scans and stature measurements were completed at baseline (day 2), preexercise (day 3), and after 30 min of moderate-intensity treadmill running (postexercise, day 3). Mean height and volume were derived for all thoracic and lumbar IVDs from digitized MRIs, and stature was determined with a stadiometer. Moderate-intensity running resulted in 6.3% ± 0.9% reduction in mean IVD height and 6.9% ± 1.0% reduction in calculated IVD volume. The day-to-day variation in mean IVD height and volume were 0.6% ± 0.6% and 0.4% ± 0.6%, respectively. This is the first study to quantify the influence of moderate-intensity running on IVD height and volume. Changes in IVD height and volume were observed throughout the thoracic and lumbar vertebral regions. These findings suggest that future studies evaluating the influence of various loading activities and recovery techniques on IVD structure should consider thoracic as well as lumbar regions of the spine.

3'-UTR Polymorphisms of MTHFR and TS Associated with Osteoporotic Vertebral Compression Fracture Susceptibility in Postmenopausal Women.

PubMed

Ahn, Tae-Keun; Kim, Jung Oh; Kim, Hyun Woo; Park, Han Sung; Shim, Jeong Hyun; Ropper, Alexander E; Han, In Bo; Kim, Nam Keun

2018-03-12

Postmenopausal osteoporosis is one of the most prominent diseases in postmenopausal women and it is increasing in prevalence with the aging population. Furthermore, osteoporosis and osteoporotic vertebral compression fractures (OVCFs) are related to mortality and decreased quality of life. Therefore, searching for biomarkers that are able to identify postmenopausal women who are at high risk of developing OVCFs is an effective strategy for improving the quality of life of patients and alleviating social and economic burdens. In this study, we investigated methylenetetrahydrofolate reductase ( MTHFR ) and thymidylate synthase ( TS ) gene polymorphisms in postmenopausal women with OVCF. We recruited 301 postmenopausal women and performed genotyping for the presence of MTHFR 2572C>A, 4869C>G and TS 1100C>T, 1170A>G. Genotyping was analyzed using the polymerization chain reaction restriction fragment length polymorphism assay. MTHFR 2572C>A and TS 1100C>T were associated with the prevalence of osteoporosis (MTHFR 2572CC versus CA+AA: odd ratio [OR] adjusted age, hypertention [HTN], and diabetes mellitus [DM] = 0.49, p = 0.012) and the occurrence of OVCFs (MTHFR 2572CC versus CA+AA: OR adjusted age, HTN, and DM = 0.38, p = 0.013; TS 1100CC versus CT+TT: OR adjusted age, HTN, and DM = 0.46, p = 0.02). Our novel finding is the identification of MTHFR and TS genetic variants that decrease susceptibility to OVCFs. Our findings suggest that polymorphisms in the MTHFR and TS genes are associated with susceptibility to osteoporosis and OVCFs in postmenopausal women.

The Neurological Compromised Spine Due to Ewing Sarcoma. What First: Surgery or Chemotherapy? Therapy, Survival, and Neurological Outcome of 15 Cases With Primary Ewing Sarcoma of the Vertebral Column.

PubMed

Mirzaei, Lida; Kaal, Suzanne E J; Schreuder, Hendrik W B; Bartels, Ronald H M A

2015-11-01

The vertebral column is an infrequent site of primary involvement in Ewing sarcoma. Yet when Ewing sarcoma is found in the spine, the urge for decompression is high because of the often symptomatic compression of neural structures. It is unclear in alleviating a neurological deficit whether chemotherapy is preferred over decompressive laminectomy. To underline, in this case series, the efficiency of initial chemotherapy before upfront surgery in the setting of high-grade spinal cord or cauda equina compression of primary Ewing sarcoma. Fifteen patients with Ewing sarcoma primarily located in the spine were treated at our institution between 1983 and 2015. Localization, neurological deficit expressed as Frankel grade, and outcome expressed as Rankin scale before and after initial chemotherapy, the recurrence rate, and overall survival were evaluated. The multidisciplinary approach of 1 case will be discussed in detail. Nine patients (60%) were female. The age at presentation was 15.0 ± 5.5 years (range: 0.9-22.8 years). Ten patients (67%) were initially treated with chemotherapy, and 1 patient (7%) was treated primarily with radiotherapy followed by chemotherapy. The remaining 4 patients (27%) were initially treated with decompressive surgery. All patients treated primarily nonsurgically improved neurologically at follow-up, showing the importance of chemotherapy as an effective initial treatment option. Adequate and quick decompression of neural structures with similar results can be achieved by chemotherapy and radiotherapy, avoiding the local spill of malignant cells.

Thoracolumbar spine model with articulated ribcage for the prediction of dynamic spinal loading.

PubMed

Ignasiak, Dominika; Dendorfer, Sebastian; Ferguson, Stephen J

2016-04-11

Musculoskeletal modeling offers an invaluable insight into the spine biomechanics. A better understanding of thoracic spine kinetics is essential for understanding disease processes and developing new prevention and treatment methods. Current models of the thoracic region are not designed for segmental load estimation, or do not include the complex construct of the ribcage, despite its potentially important role in load transmission. In this paper, we describe a numerical musculoskeletal model of the thoracolumbar spine with articulated ribcage, modeled as a system of individual vertebral segments, elastic elements and thoracic muscles, based on a previously established lumbar spine model and data from the literature. The inverse dynamics simulations of the model allow the prediction of spinal loading as well as costal joints kinetics and kinematics. The intradiscal pressure predicted by the model correlated well (R(2)=0.89) with reported intradiscal pressure measurements, providing a first validation of the model. The inclusion of the ribcage did not affect segmental force predictions when the thoracic spine did not perform motion. During thoracic motion tasks, the ribcage had an important influence on the predicted compressive forces and muscle activation patterns. The compressive forces were reduced by up to 32%, or distributed more evenly between thoracic vertebrae, when compared to the predictions of the model without ribcage, for mild thoracic flexion and hyperextension tasks, respectively. The presented musculoskeletal model provides a tool for investigating thoracic spine loading and load sharing between vertebral column and ribcage during dynamic activities. Further validation for specific applications is still necessary. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of Facet Joint Injection Reducing the Need for Percutaneous Vertebroplasty in Vertebral Compression Fractures

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

Im, Tae Seong; Lee, Joon Woo; Lee, Eugene

ObjectiveTo evaluate the effects of facet joint injection (FJI) reducing the need for percutaneous vertebroplasty (PVP) in cases of vertebral compression fracture (VCF).Materials and MethodsA total of 169 patients who were referred to the radiology department of our institution for PVP between January 2011 and December 2014 were retrospectively evaluated. The effectiveness of FJI was evaluated by the proportion of patients who cancelled PVP and who experienced reduced pain. In addition, by means of medical chart and MRI review, those clinical factors (age, sex, history of trauma, amount of injected steroids and interval days elapsed between VCF and FJI) andmore » MR image factors (kyphosis angle, height loss, single or multiple level of VCF, burst fracture, central canal compromise, posterior element injury) that were believed to be significant for the effectiveness of FJI were statistically analysed.ResultsIn the 26 patients with FJI prior to PVP, six (23 %) patients cancelled PVP with considerable improvement in reported pain. In the 20 patients with PVP after FJI, improvement in pain after FJI was reported by six patients, resulting in a total of 12 patients (46 %) who experienced reduced pain after FJI. Clinical factors and MR image factors did not show any statistically significant difference between those groups, divided by PVP cancellation and by improvement of pain.ConclusionAfter FJI prior to PVP, about one quarter of patients cancelled PVP due to reduced pain and overall about half of the patients experienced reduced pain.« less

Fully compressible solutions for early stage Richtmyer–Meshkov instability

DOE PAGES

Margolin, Len G.; Reisner, Jon Michael

2016-10-27

Here, we will consider the effects of compressibility and viscosity on the early dynamics of the Richtmyer–Meshkov instability (RMI). In particular, we will combine theory, scaling, and high resolution simulation of RMI to probe the details of the initial compression and the subsequent viscous damping as a shock interacts with a density discontinuity. We will propose a refinement of the classic 1D model for the linear regime of RMI that, for small initial perturbation wavelengths, more accurately reproduces the 2D dynamics of a fully resolved numerical simulation.

PDF methods for combustion in high-speed turbulent flows

NASA Technical Reports Server (NTRS)

Pope, Stephen B.

1995-01-01

This report describes the research performed during the second year of this three-year project. The ultimate objective of the project is extend the applicability of probability density function (pdf) methods from incompressible to compressible turbulent reactive flows. As described in subsequent sections, progress has been made on: (1) formulation and modelling of pdf equations for compressible turbulence, in both homogeneous and inhomogeneous inert flows; and (2) implementation of the compressible model in various flow configurations, namely decaying isotropic turbulence, homogeneous shear flow and plane mixing layer.

Microstructural Evolution at Micro/Meso-Scale in an Ultrafine-Grained Pure Aluminum Processed by Equal-Channel Angular Pressing with Subsequent Annealing Treatment.

PubMed

Xu, Jie; Li, Jianwei; Zhu, Xiaocheng; Fan, Guohua; Shan, Debin; Guo, Bin

2015-11-04

Micro-forming with ultrafine-grained (UFG) materials is a promising direction for the fabrication of micro-electro-mechanical systems (MEMS) components due to the improved formability, good surface quality, and excellent mechanical properties it provides. In this paper, micro-compression tests were performed using UFG pure aluminum processed by equal-channel angular pressing (ECAP) with subsequent annealing treatment. Microstructural evolution was investigated by electron back-scattered diffraction (EBSD) and transmission electron microscopy (TEM). The results show that microstructural evolutions during compression tests at the micro/meso-scale in UFG pure Al are absolutely different from the coarse-grained (CG) materials. A lot of low-angle grain boundaries (LAGBs) and recrystallized fine grains are formed inside of the original large grains in CG pure aluminum after micro-compression. By contrast, ultrafine grains are kept with few sub-grain boundaries inside the grains in UFG pure aluminum, which are similar to the original microstructure before micro-compression. The surface roughness and coordinated deformation ability can be signmicrostructure; micro/meso-forming; ultrafine grains; ECAP; aluminumificantly improved with UFG pure aluminum, which demonstrates that the UFG materials have a strong potential application in micro/meso-forming.

AmphiFoxE4, an amphioxus winged helix/forkhead gene encoding a protein closely related to vertebrate thyroid transcription factor-2: expression during pharyngeal development

NASA Technical Reports Server (NTRS)

Yu, Jr-Kai; Holland, Linda Z.; Jamrich, Milan; Blitz, Ira L.; Hollan, Nicholas D.

2002-01-01

The full-length sequence and developmental expression of amphioxus AmphiFoxE4 are described. Transcripts of the gene are first detected in the pharyngeal endoderm, where the club-shaped gland is forming and subsequently in the definitive gland itself. AmphiFoxE4 is closely related to vertebrate genes encoding the thyroid-specific transcription factor-2 (TTF2), which plays an early developmental role in the morphogenesis of the thyroid gland and a later role in hormone-mediated control of thyroid function. In amphioxus, AmphiFoxE4 expression is not thyroid specific because the club-shaped gland, the only structure expressing the gene, is not homologous to the vertebrate thyroid; instead, the thyroid homologue of amphioxus is a specialized region of the pharyngeal endoderm called the endostyle. We propose that (a) the pharynx of an amphioxus-like ancestor of the vertebrates included a club-shaped gland that expressed FoxE4 as well as an endostyle that did not, and (b) the club-shaped gland soon disappeared in the vertebrate line of descent but (c) not before there was a homeogenetic transfer of FoxE4 expression from the club-shaped gland to the nearby endostyle. Such a transfer could have provided part of the genetic program enabling the endostyle to separate from the pharyngeal endoderm and migrate away as the rudiment of the thyroid gland.

A multidimensional approach for detecting species patterns in Malagasy vertebrates

PubMed Central

Yoder, Anne D.; Olson, Link E.; Hanley, Carol; Heckman, Kellie L.; Rasoloarison, Rodin; Russell, Amy L.; Ranivo, Julie; Soarimalala, Voahangy; Karanth, K. Praveen; Raselimanana, Achille P.; Goodman, Steven M.

2005-01-01

The biodiversity of Madagascar is extraordinarily distinctive, diverse, and endangered. It is therefore urgent that steps be taken to document, describe, interpret, and protect this exceptional biota. As a collaborative group of field and laboratory biologists, we employ a suite of methodological and analytical tools to investigate the vertebrate portion of Madagascar's fauna. Given that species are the fundamental unit of evolution, where micro- and macroevolutionary forces converge to generate biological diversity, a thorough understanding of species distribution and abundance is critical for understanding the evolutionary, ecological, and biogeographic forces that have shaped Malagasy vertebrate diversity. We illustrate the means by which we apply Mayr's “three basic tasks” of the systematist [Mayr, E. (1942) Systematics and the Origin of Species from the Viewpoint of a Zoologist (Harvard Univ. Press, Cambridge, MA)] to identify, classify, and study the organisms that together constitute Madagascar's vertebrate community. Using field inventory methods, specimen-based studies, and morphological and molecular analyses, we formulate hypotheses of species identity that then serve as the foundation for subsequent studies of biology and history. Our experience, as well as that of other investigators, has shown that much of the vertebrate species diversity in Madagascar is “cryptic” for both biological and practical reasons. Beyond issues of cryptic biological diversity, the resolution of species identity in Madagascar has been hampered because of a lack of vouchered comparative material at the population level. Through our activities, we are attempting to remedy these limitations while simultaneously enhancing research capacity in Madagascar. PMID:15851666

Streamlined Genome Sequence Compression using Distributed Source Coding

PubMed Central

Wang, Shuang; Jiang, Xiaoqian; Chen, Feng; Cui, Lijuan; Cheng, Samuel

2014-01-01

We aim at developing a streamlined genome sequence compression algorithm to support alternative miniaturized sequencing devices, which have limited communication, storage, and computation power. Existing techniques that require heavy client (encoder side) cannot be applied. To tackle this challenge, we carefully examined distributed source coding theory and developed a customized reference-based genome compression protocol to meet the low-complexity need at the client side. Based on the variation between source and reference, our protocol will pick adaptively either syndrome coding or hash coding to compress subsequences of changing code length. Our experimental results showed promising performance of the proposed method when compared with the state-of-the-art algorithm (GRS). PMID:25520552

[Neurovascular compression of the medulla oblongata: a rare cause of secondary hypertension].

PubMed

Nádas, Judit; Czirják, Sándor; Igaz, Péter; Vörös, Erika; Jermendy, György; Rácz, Károly; Tóth, Miklós

2014-05-25

Compression of the rostral ventrolateral medulla oblongata is one of the rarely identified causes of refractory hypertension. In patients with severe, intractable hypertension caused by neurovascular compression, neurosurgical decompression should be considered. The authors present the history of a 20-year-old man with severe hypertension. After excluding other possible causes of secondary hypertension, the underlying cause of his high blood pressure was identified by the demonstration of neurovascular compression shown by magnetic resonance angiography and an increased sympathetic activity (sinus tachycardia) during the high blood pressure episodes. Due to frequent episodes of hypertensive crises, surgical decompression was recommended, which was performed with the placement of an isograft between the brainstem and the left vertebral artery. In the first six months after the operation, the patient's blood pressure could be kept in the normal range with significantly reduced doses of antihypertensive medication. Repeat magnetic resonance angiography confirmed the cessation of brainstem compression. After six months, increased blood pressure returned periodically, but to a smaller extent and less frequently. Based on the result of magnetic resonance angiography performed 22 months after surgery, re-operation was considered. According to previous literature data long-term success can only be achieved in one third of patients after surgical decompression. In the majority of patients surgery results in a significant decrease of blood pressure, an increased efficiency of antihypertensive therapy as well as a decrease in the frequency of highly increased blood pressure episodes. Thus, a significant improvement of the patient's quality of life can be achieved. The case of this patient is an example of the latter scenario.

Unicameral bone cyst of a cervical vertebral body and lateral mass with associated pathological fracture in a child. Case report and review of the literature.

PubMed

Snell, B E; Adesina, A; Wolfla, C E

2001-10-01

The authors present the case of a 10-year-old girl with a history of cervical trauma in whom a cystic lesion was found to involve all three columns of C-7 with evidence of pathological fracture. Computerized tomography scanning revealed a lytic lesion with sclerotic margins involving the left vertebral body, pedicle, lateral mass, and lamina of C-7 with an associated pathological compression fracture. Magnetic resonance imaging demonstrated mixed signal on both T1- and T2-weighted sequences, with cystic and enhancing solid portions. Magnetic resonance angiography demonstrated anterior displacement of the left vertebral artery at C-7. The patient underwent C-7 subtotal corpectomy and posterior resection of the tumor mass; anterior and posterior fusion were performed in which instrumentation was placed. Histological examination disclosed cystic areas lined by fibromembranous tissue with calcification and osteoid deposits consistent with unicameral bone cyst. Of the four previously reported cases of unicameral bone cysts in the cervical spine, none involved all three columns simultaneously or was associated with pathological fracture. The most common differential diagnostic considerations for cystic lesions in the spine are aneurysmal bone cyst, osteoblastoma, or giant cell tumor of bone. Unicameral bone cyst, in this location, although rare, must be considered in the differential diagnosis and may require resection and spinal reconstruction.

Correlation between clinical severity and type and degree of pectus excavatum in twelve brachycephalic dogs.

PubMed

Hassan, Elham A; Hassan, Marwa H; Torad, Faisal A

2018-05-18

The aim of the study was to correlate the clinical severity of pectus excavatum with its type and degree based on objective radiographic evaluation. Twelve brachycephalic dogs were included. Grading of the clinical severity was done based on a 6-point grading score. Thoracic radiographs were used to calculate the frontosagittal and vertebral indices at the tenth thoracic vertebra and the vertebra overlying the excavatum. Correlation between the clinical severity score and frontosagittal and vertebral indices was evaluated using Pearson's correlation coefficient. Typical pectus excavatum was recorded in the caudal sternum in seven dogs, with a mean clinical severity score of 1.7 ± 1.4, whereas in five dogs, atypical mid-sternal deviation was recorded with a mean clinical severity score of 3.8 ± 0.7. A strong correlation (r=0.7) was recorded between the clinical severity score and vertebral index in the atypical form, whereas a weak correlation (r=0.02) was recorded in the typical form (P<0.05). The clinical severity and degree of pectus excavatum was poorly correlated (r=0.3) in the typical form of pectus excavatum, whereas it was strongly correlated (r=0.9) in the atypical form. Pectus excavatum in dogs is associated with compressive cardiopulmonary dysfunction, which depends mainly on the site/type of deviation rather than the degree of deviation.

3-Dimensional printing guide template assisted percutaneous vertebroplasty: Technical note.

PubMed

Li, Jian; Lin, JiSheng; Yang, Yong; Xu, JunChuan; Fei, Qi

2018-06-01

Percutaneous vertebroplasty (PVP) is currently considered as an effective treatment for pain caused by acute osteoporotic vertebral compression fracture. Recently, puncture-related complications are increasingly reported. It's important to find a precise technique to reduce the puncture-related complications. We report a case and discussed the novel surgical technique with step-by-step operating procedures, to introduce the precise PVP assisted by a 3-dimensional printing guide template. Based on the preoperative CT scan and infrared scan data, a well-designed individual guide template could be established in a 3-dimensional reconstruction software and printed out by a 3-dimensional printer. In real operation, by matching the guide template to patient's back skin, cement needles' insertion orientation and depth were easily established. Only 14 times C-arm fluoroscopy with HDF mode (total exposure dose was 4.5 mSv) were required during the procedure. The operation took only 17 min. Cement distribution in the vertebral body was very good without any puncture-related complications. Pain was significantly relieved after surgery. In conclusion, the novel precise 3-dimensional printing guide template system may allow (1) comprehensive visualization of the fractured vertebral body and the individual surgical planning, (2) the perfect fitting between skin and guide template to ensure the puncture stability and accuracy, and (3) increased puncture precision and decreased puncture-related complications, surgical time and radiation exposure. Copyright © 2018 Elsevier Ltd. All rights reserved.

Pathogenesis, Diagnosis, and Treatment of Cervical Vertigo.

PubMed

Li, Yongchao; Peng, Baogan

2015-01-01

Cervical vertigo is characterized by vertigo from the cervical spine. However, whether cervical vertigo is an independent entity still remains controversial. In this narrative review, we outline the basic science and clinical evidence for cervical vertigo according to the current literature. So far, there are 4 different hypotheses explaining the vertigo of a cervical origin, including proprioceptive cervical vertigo, Barré-Lieou syndrome, rotational vertebral artery vertigo, and migraine-associated cervicogenic vertigo. Proprioceptive cervical vertigo and rotational vertebral artery vertigo have survived with time. Barré-Lieou syndrome once was discredited, but it has been resurrected recently by increased scientific evidence. Diagnosis depends mostly on patients' subjective feelings, lacking positive signs, specific laboratory examinations and clinical trials, and often relies on limited clinical experiences of clinicians. Neurological, vestibular, and psychosomatic disorders must first be excluded before the dizziness and unsteadiness in cervical pain syndromes can be attributed to a cervical origin. Treatment for cervical vertigo is challenging. Manual therapy is recommended for treatment of proprioceptive cervical vertigo. Anterior cervical surgery and percutaneous laser disc decompression are effective for the cervical spondylosis patients accompanied with Barré-Liéou syndrome. As to rotational vertebral artery vertigo, a rare entity, when the exact area of the arterial compression is identified through appropriate tests such as magnetic resonance angiography (MRA), computed tomography angiography (CTA) or digital subtraction angiography (DSA) decompressive surgery should be the chosen treatment.

Pulmonary ventilation-perfusion mismatch: a novel hypothesis for how diving vertebrates may avoid the bends.

PubMed

Garcia Párraga, Daniel; Moore, Michael; Fahlman, Andreas

2018-04-25

Hydrostatic lung compression in diving marine mammals, with collapsing alveoli blocking gas exchange at depth, has been the main theoretical basis for limiting N 2 uptake and avoiding gas emboli (GE) as they ascend. However, studies of beached and bycaught cetaceans and sea turtles imply that air-breathing marine vertebrates may, under unusual circumstances, develop GE that result in decompression sickness (DCS) symptoms. Theoretical modelling of tissue and blood gas dynamics of breath-hold divers suggests that changes in perfusion and blood flow distribution may also play a significant role. The results from the modelling work suggest that our current understanding of diving physiology in many species is poor, as the models predict blood and tissue N 2 levels that would result in severe DCS symptoms (chokes, paralysis and death) in a large fraction of natural dive profiles. In this review, we combine published results from marine mammals and turtles to propose alternative mechanisms for how marine vertebrates control gas exchange in the lung, through management of the pulmonary distribution of alveolar ventilation ([Formula: see text]) and cardiac output/lung perfusion ([Formula: see text]), varying the level of [Formula: see text] in different regions of the lung. Man-made disturbances, causing stress, could alter the [Formula: see text] mismatch level in the lung, resulting in an abnormally elevated uptake of N 2 , increasing the risk for GE. Our hypothesis provides avenues for new areas of research, offers an explanation for how sonar exposure may alter physiology causing GE and provides a new mechanism for how air-breathing marine vertebrates usually avoid the diving-related problems observed in human divers. © 2018 The Authors.

Volume of Lytic Vertebral Body Metastatic Disease Quantified Using Computed Tomography–Based Image Segmentation Predicts Fracture Risk After Spine Stereotactic Body Radiation Therapy

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

Thibault, Isabelle; Department of Radiation Oncology, Centre Hospitalier de L'Universite de Québec–Université Laval, Quebec, Quebec; Whyne, Cari M.

Purpose: To determine a threshold of vertebral body (VB) osteolytic or osteoblastic tumor involvement that would predict vertebral compression fracture (VCF) risk after stereotactic body radiation therapy (SBRT), using volumetric image-segmentation software. Methods and Materials: A computational semiautomated skeletal metastasis segmentation process refined in our laboratory was applied to the pretreatment planning CT scan of 100 vertebral segments in 55 patients treated with spine SBRT. Each VB was segmented and the percentage of lytic and/or blastic disease by volume determined. Results: The cumulative incidence of VCF at 3 and 12 months was 14.1% and 17.3%, respectively. The median follow-up was 7.3 months (range,more » 0.6-67.6 months). In all, 56% of segments were determined lytic, 23% blastic, and 21% mixed, according to clinical radiologic determination. Within these 3 clinical cohorts, the segmentation-determined mean percentages of lytic and blastic tumor were 8.9% and 6.0%, 0.2% and 26.9%, and 3.4% and 15.8% by volume, respectively. On the basis of the entire cohort (n=100), a significant association was observed for the osteolytic percentage measures and the occurrence of VCF (P<.001) but not for the osteoblastic measures. The most significant lytic disease threshold was observed at ≥11.6% (odds ratio 37.4, 95% confidence interval 9.4-148.9). On multivariable analysis, ≥11.6% lytic disease (P<.001), baseline VCF (P<.001), and SBRT with ≥20 Gy per fraction (P=.014) were predictive. Conclusions: Pretreatment lytic VB disease volumetric measures, independent of the blastic component, predict for SBRT-induced VCF. Larger-scale trials evaluating our software are planned to validate the results.« less

Percutaneous Vertebroplasty Versus Conservative Treatment and Rehabilitation in Women with Vertebral Fractures due to Osteoporosis: A Prospective Comparative Study.

PubMed

Macías-Hernández, Salvador Israel; Chávez-Arias, Daniel David; Miranda-Duarte, Antonio; Coronado-Zarco, Roberto; Diez-García, María Pilar

2015-01-01

Percutaneous vertebroplasty is commonly used in the management of osteoporosis-related vertebral fractures, although there is controversy on its superiority over conservative treatment. Here we compare pain and function in women with vertebral osteoporotic fractures who underwent percutaneous vertebroplasty versus conservative treatment with a protocolized rehabilitation program. A longitudinal and comparative prospective study was conducted. Women ≥ 60 years of age with a diagnosis of osteoporosis who had at least one vertebral thoracic or lumbar compression fracture were included and divided into two groups, conservative treatment or vertebroplasty. The Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) were used to assess pain and function, respectively, as the outcome measures. We included 31 patients, 13 (42%) treated with percutaneous vertebroplasty and 18 (58%) with conservative treatment. Baseline clinical characteristics, bone densitometry and fracture data were similar in both groups. At baseline, VAS was 73.1 ± 28.36 in the vertebroplasty group and 68.6 ± 36.1 mm in the conservative treatment group (p = 0.632); at three months it was 33.11 ± 10.1 vs. 42 ± 22.21 mm (p = 0.111); and at 12 months, 32.3 ± 11.21 vs. 36.1 ± 12.36 mm (p = 0.821). The ODI at baseline was 83% in the vertebroplasty group vs. 85% for conservative management (p = 0.34); at three months, 36 vs. 39% (p = 0.36); and at 12 months, 29.38 vs. 28.33% (p = 0.66). Treatment with percutaneous vertebroplasty had no advantages over conservative treatment for pain and function in this group of women ≥ 60 years of age with osteoporosis.

Evolution of phototransduction, vertebrate photoreceptors and retina.

PubMed

Lamb, Trevor D

2013-09-01

Evidence is reviewed from a wide range of studies relevant to the evolution of vertebrate photoreceptors and phototransduction, in order to permit the synthesis of a scenario for the major steps that occurred during the evolution of cones, rods and the vertebrate retina. The ancestral opsin originated more than 700 Mya (million years ago) and duplicated to form three branches before cnidarians diverged from our own lineage. During chordate evolution, ciliary opsins (C-opsins) underwent multiple stages of improvement, giving rise to the 'bleaching' opsins that characterise cones and rods. Prior to the '2R' rounds of whole genome duplication near the base of the vertebrate lineage, 'cone' photoreceptors already existed; they possessed a transduction cascade essentially the same as in modern cones, along with two classes of opsin: SWS and LWS (short- and long-wave-sensitive). These cones appear to have made synaptic contact directly onto ganglion cells, in a two-layered retina that resembled the pineal organ of extant non-mammalian vertebrates. Interestingly, those ganglion cells appear to be descendants of microvillar photoreceptor cells. No lens was associated with this two-layered retina, and it is likely to have mediated circadian timing rather than spatial vision. Subsequently, retinal bipolar cells evolved, as variants of ciliary photoreceptors, and greatly increased the computational power of the retina. With the advent of a lens and extraocular muscles, spatial imaging information became available for central processing, and gave rise to vision in vertebrates more than 500 Mya. The '2R' genome duplications permitted the refinement of cascade components suitable for both rods and cones, and also led to the emergence of five visual opsins. The exact timing of the emergence of 'true rods' is not yet clear, but it may not have occurred until after the divergence of jawed and jawless vertebrates. Copyright © 2013 The Author. Published by Elsevier Ltd.. All rights reserved.

Development of the Synarcual in the Elephant Sharks (Holocephali; Chondrichthyes): Implications for Vertebral Formation and Fusion.

PubMed

Johanson, Zerina; Boisvert, Catherine; Maksimenko, Anton; Currie, Peter; Trinajstic, Kate

2015-01-01

The synarcual is a structure incorporating multiple elements of two or more anterior vertebrae of the axial skeleton, forming immediately posterior to the cranium. It has been convergently acquired in the fossil group 'Placodermi', in Chondrichthyes (Holocephali, Batoidea), within the teleost group Syngnathiformes, and to varying degrees in a range of mammalian taxa. In addition, cervical vertebral fusion presents as an abnormal pathology in a variety of human disorders. Vertebrae develop from axially arranged somites, so that fusion could result from a failure of somite segmentation early in development, or from later heterotopic development of intervertebral bone or cartilage. Examination of early developmental stages indicates that in the Batoidea and the 'Placodermi', individual vertebrae developed normally and only later become incorporated into the synarcual, implying regular somite segmentation and vertebral development. Here we show that in the holocephalan Callorhinchus milii, uniform and regular vertebral segmentation also occurs, with anterior individual vertebra developing separately with subsequent fusion into a synarcual. Vertebral elements forming directly behind the synarcual continue to be incorporated into the synarcual through growth. This appears to be a common pattern through the Vertebrata. Research into human disorders, presenting as cervical fusion at birth, focuses on gene misexpression studies in humans and other mammals such as the mouse. However, in chondrichthyans, vertebral fusion represents the normal morphology, moreover, taxa such Leucoraja (Batoidea) and Callorhinchus (Holocephali) are increasingly used as laboratory animals, and the Callorhinchus genome has been sequenced and is available for study. Our observations on synarcual development in three major groups of early jawed vertebrates indicate that fusion involves heterotopic cartilage and perichondral bone/mineralised cartilage developing outside the regular skeleton. We suggest that chondrichthyans have potential as ideal extant models for identifying the genes involved in these processes, for application to human skeletal heterotopic disorders.

Development of the Synarcual in the Elephant Sharks (Holocephali; Chondrichthyes): Implications for Vertebral Formation and Fusion

PubMed Central

Johanson, Zerina; Boisvert, Catherine; Maksimenko, Anton; Currie, Peter; Trinajstic, Kate

2015-01-01

The synarcual is a structure incorporating multiple elements of two or more anterior vertebrae of the axial skeleton, forming immediately posterior to the cranium. It has been convergently acquired in the fossil group ‘Placodermi’, in Chondrichthyes (Holocephali, Batoidea), within the teleost group Syngnathiformes, and to varying degrees in a range of mammalian taxa. In addition, cervical vertebral fusion presents as an abnormal pathology in a variety of human disorders. Vertebrae develop from axially arranged somites, so that fusion could result from a failure of somite segmentation early in development, or from later heterotopic development of intervertebral bone or cartilage. Examination of early developmental stages indicates that in the Batoidea and the ‘Placodermi’, individual vertebrae developed normally and only later become incorporated into the synarcual, implying regular somite segmentation and vertebral development. Here we show that in the holocephalan Callorhinchus milii, uniform and regular vertebral segmentation also occurs, with anterior individual vertebra developing separately with subsequent fusion into a synarcual. Vertebral elements forming directly behind the synarcual continue to be incorporated into the synarcual through growth. This appears to be a common pattern through the Vertebrata. Research into human disorders, presenting as cervical fusion at birth, focuses on gene misexpression studies in humans and other mammals such as the mouse. However, in chondrichthyans, vertebral fusion represents the normal morphology, moreover, taxa such Leucoraja (Batoidea) and Callorhinchus (Holocephali) are increasingly used as laboratory animals, and the Callorhinchus genome has been sequenced and is available for study. Our observations on synarcual development in three major groups of early jawed vertebrates indicate that fusion involves heterotopic cartilage and perichondral bone/mineralised cartilage developing outside the regular skeleton. We suggest that chondrichthyans have potential as ideal extant models for identifying the genes involved in these processes, for application to human skeletal heterotopic disorders. PMID:26339918

Insight into Bone-Derived Biological Apatite: Ultrastructure and Effect of Thermal Treatment

PubMed Central

Liu, Quan; Pan, Haobo; Chen, Zhuofan; Matinlinna, Jukka Pekka

2015-01-01

Objectives. This study aims at examining the ultrastructure of bone-derived biological apatite (BAp) from a series of small vertebrates and the effect of thermal treatment on its physiochemical properties. Materials and Methods. Femurs/fin rays and vertebral bodies of 5 kinds of small vertebrates were firstly analyzed with X-ray microtomography. Subsequently, BAp was obtained with thermal treatment and low power plasma ashing, respectively. The properties of BAp, including morphology, functional groups, and crystal characteristics were then analyzed. Results. The bones of grouper and hairtail were mainly composed of condensed bone. Spongy bone showed different distribution in the bones from frog, rat, and pigeon. No significant difference was found in bone mineral density of condensed bone and trabecular thickness of spongy bone. Only platelet-like crystals were observed for BAp obtained by plasma ashing, while rod-like and irregular crystals were both harvested from the bones treated by sintering. A much higher degree of crystallinity and larger crystal size but a lower content of carbonate were detected in the latter. Conclusion. Platelet-like BAp is the common inorganic component of vertebrate bones. BAp distributing in condensed and spongy bone may exhibit differing thermal reactivity. Thermal treatment may alter BAp's in vivo structure and composition. PMID:25695088

Changes in Small Intestine Tissue Compressed by a Linear Stapler Based on Cole Y Model.

PubMed

Zhou, Yu; Ren, Binbin; Li, Boting; Xu, Jingjing; Jin, Yiyun; Song, Chengli

2016-12-01

Clarifying changes in gastrointestinal tissue compressed by surgical stapler is a crucial prerequisite for stapler design optimization. For this study, a stapler was modified, and multifrequency bioimpedance of a porcine small intestine tissue compressed by the stapler was measured. The Cole Y model was fitted to the bioimpedance, and changes in tissue were analyzed using model parameters: G 0 , extracellular fluid conductance; ΔG, intracellular fluid conductance; C cpeF , equivalent capacitance of cell membrane. The changes could be divided into two stages: first, all parameters decreased sharply with slopes more than 15.70 ± 2.67, 4.25 ± 1.23 μS/s and 72.68 ± 6.99 pF/s respectively; and subsequently, with an increase in compression strength, G 0 decreased with slopes less than 2.54 ± 0.40 μS/s, ΔG decreased slightly with slope of 0.26 ± 0.04 μS/s after fluctuating mildly, and C cpeF remained nearly invariant after initially increasing with slope of -2.94 ± 0.64 pF/s. In conclusion, when the stapler is closed, a portion of tissue is squeezed out of the measurement space, causing all parameters' sharp decrease. Subsequently, the stapler continues compressing the tissue, leading to extracellular fluid expulsion. The changes in intracellular fluid are related to the compression strength and may be explained by cell restoration. This study could provide a basis for stapler design optimization.

Stability of compressible Taylor-Couette flow

NASA Technical Reports Server (NTRS)

Kao, K.; Chow, C.

1992-01-01

The objectives of this paper are to: (1) develop both analytical and numerical tools that can be used to predict the onset of instability and subsequently to simulate the transition process by which the originally laminar flow evolves into a turbulent flow; and (2) conduct the preliminary investigations with the purpose of understanding the mechanisms of the vortical structures of the compressible flow between tow concentric cylinders.

Left-right asymmetry of the gnathostome skull: its evolutionary, developmental, and functional aspects.

PubMed

Compagnucci, Claudia; Fish, Jennifer; Depew, Michael J

2014-06-01

Much of the gnathostome (jawed vertebrate) evolutionary radiation was dependent on the ability to sense and interpret the environment and subsequently act upon this information through utilization of a specialized mode of feeding involving the jaws. While the gnathostome skull, reflective of the vertebrate baüplan, typically is bilaterally symmetric with right (dextral) and left (sinistral) halves essentially representing mirror images along the midline, both adaptive and abnormal asymmetries have appeared. Herein we provide a basic primer on studies of the asymmetric development of the gnathostome skull, touching briefly on asymmetry as a field of study, then describing the nature of cranial development and finally underscoring evolutionary and functional aspects of left-right asymmetric cephalic development. © 2014 Wiley Periodicals, Inc.

Disintegration of cervical intervertebral BOP grafts with neurological sequelae: a report of two cases.

PubMed

Dorward, N L; Malik, N N; Illingworth, R D

1997-02-01

We report the case histories of two patients treated in our unit for cervical radiculopathy by anterior cervical discectomy and BOP grafting. Both grafts disintegrated within 6 weeks of insertion resulting in increased neurological deficit from cervical cord compression. At reoperation fibres from the grafts were found to have separated and the larger fragments had extruded into the vertebral canal. No evidence of infection was seen, but a foreign body reaction was found in one case. Following graft removal the patients improved symptomatically although one was left with permanent mild biceps weakness.

[Rehabilitation treatment of patients with uncomplicated fractures of the spine at a hospital rehabilitation center].

PubMed

Bagaturiia, G O; Chanov, V L; Kutushev, F Kh

1989-02-01

The authors make an analysis of treatment of 188 patients with noncomplicated compressive fractures of the vertebral column in the thoracolumbar part performed at the stationary rehabilitation center. The course of restorative treatment was as long as 31-40 days and included individual and group trainings of exercise therapy, massage, hydrokinesotherapy, thermo-, electro-, photo- and magnetotherapy. Results of the treatment were followed in 81 patients. Excellent and good results were obtained in 43 patients (53%), unsatisfactory--in 7 patients (8.6%). The period of follow-up observation was from 1 month to 1 year.

Flight Physical Standards of the 1980’s: Spinal Column Considerations

DTIC Science & Technology

1979-10-01

disease and spondylosis deformans. In addition, the role of vertebral body fractures oni subsequent spinal column impact is discussed. SECURITY...11 Spondylosis D eform ans ......................................... ................... 11 III...5th lumbar vertebra supports the superimposed weight of the torso upon the inclined plane of the sacrum. The necessity for bony continuity of the 5th

The Origin of Compressible Magnetic Turbulence in the Very Local Interstellar Medium

NASA Astrophysics Data System (ADS)

Zank, G. P.; Du, S.; Hunana, P.

2017-06-01

Voyager 1 observed compressible magnetic turbulence in the very local interstellar medium (VLISM). We show that inner heliosheath (IHS) fast- and slow-mode waves incident on the heliopause (HP) generate VLISM fast-mode waves only that propagate into the VLISM. We suggest that this is the origin of compressible turbulence in the VLISM. We show that fast- and slow-mode waves transmitted across a tangential discontinuity such as the HP are strongly refracted on crossing the HP and subsequently propagate at highly oblique angles to the VLISM magnetic field. Thus, fast-mode waves in the VLISM contribute primarily to the compressible and not the transverse components of the VLISM fluctuating magnetic field variance < δ {\\hat{B}}2> since < δ {\\hat{B}}{fz}2> \

A compression scheme for radio data in high performance computing

NASA Astrophysics Data System (ADS)

Masui, K.; Amiri, M.; Connor, L.; Deng, M.; Fandino, M.; Höfer, C.; Halpern, M.; Hanna, D.; Hincks, A. D.; Hinshaw, G.; Parra, J. M.; Newburgh, L. B.; Shaw, J. R.; Vanderlinde, K.

2015-09-01

We present a procedure for efficiently compressing astronomical radio data for high performance applications. Integrated, post-correlation data are first passed through a nearly lossless rounding step which compares the precision of the data to a generalized and calibration-independent form of the radiometer equation. This allows the precision of the data to be reduced in a way that has an insignificant impact on the data. The newly developed Bitshuffle lossless compression algorithm is subsequently applied. When the algorithm is used in conjunction with the HDF5 library and data format, data produced by the CHIME Pathfinder telescope is compressed to 28% of its original size and decompression throughputs in excess of 1 GB/s are obtained on a single core.

Epithelioid Hemangioma of the Thoracic Spine: A Case Report and Review of the Literature.

PubMed

Okada, Eijiro; Matsumoto, Morio; Nishida, Mitsuhiro; Iga, Takahito; Morishita, Midori; Tezuka, Masaki; Mukai, Kiyoshi; Kobayashi, Eisuke; Watanabe, Kota

2017-10-25

Osseous epithelioid hemangioma is uncommon, and reports of epithelioid hemangiomas of the spine are especially rare. Case report. A 43-year-old male was referred to our department with progressive gait disturbance. CT scans showed a lucent mass in the vertebral body at the T3 level. MRI of the thoracic spine showed a strongly enhanced mass compressing the spinal cord. The patient underwent laminectomy from T2 to T4, debulking of the tumor, and posterior fusion from T1 to T5. After the operation, the patient's neurological status improved significantly, and he was able walk without assistance. Histological examination determined that the tumor was an epithelioid hemangioma. The patient was treated with 40 Gy radiation for local control of the tumor. The patient could walk without difficulty 12 months after the surgery. This is a rare example of an epithelioid hemangioma that developed in the thoracic spine and compressed the spinal cord, and was treated successfully.

Lumbar vertebral hemangioma causing cauda equina syndrome: a case report.

PubMed

Ahn, Henry; Jhaveri, Subir; Yee, Albert; Finkelstein, Joel

2005-11-01

Case report. To report a case of lumbar hemangioma causing neurogenic claudication and early cauda equina, managed with hemostatic vertebroplasty and posterior decompression. This is the first report to our knowledge of a lumbar hemangioma causing neurogenic claudication and early cauda equina syndrome. Most hemangiomas causing neurologic symptoms occur in thoracic spine and cause spinal cord compression. Vertebroplasty as a method of hemostasis and for providing mechanical stability in this situation has not been discussed previously in the literature. L4 hemangioma was diagnosed in a 64-year-old woman with severe neurogenic claudication and early cauda equina syndrome. Preoperative angiograms showed no embolizable vessels. Posterior decompression was performed followed by bilateral transpedicular vertebroplasty. The patient received postoperative radiation to prevent recurrence. Complete relief of neurogenic claudication and cauda equina with less than 100 mL of blood loss. A lumbar hemangioma of the vertebral body, although rare, can cause neurogenic claudication and cauda equina syndrome. Intraoperative vertebroplasty can be an effective method of hemostasis and provide stability of the vertebra following posterior decompression.

Cervical Disc Deformation During Flexion–Extension in Asymptomatic Controls and Single-Level Arthrodesis Patients

PubMed Central

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

2016-01-01

The aim of this study was to characterize cervical disc deformation in asymptomatic subjects and single-level arthrodesis patients during in vivo functional motion. A validated model-based tracking technique determined vertebral motion from biplane radiographs collected during dynamic flexion–extension. Level-dependent differences in disc compression–distraction and shear deformation were identified within the anterior and posterior annulus (PA) and the nucleus of 20 asymptomatic subjects and 15 arthrodesis patients using a mixed-model statistical analysis. In asymptomatic subjects, disc compression and shear deformation per degree of flexion–extension progressively decreased from C23 to C67. The anterior and PA experienced compression–distraction deformation of up to 20%, while the nucleus region was compressed between 0% (C67) and 12% (C23). Peak shear deformation ranged from 16% (at C67) to 33% (at C45). In the C5–C6 arthrodesis group, C45 discs were significantly less compressed than in the control group in all disc regions (all p ≤ 0.026). In the C6–C7 arthrodesis group, C56 discs were significantly less compressed than the control group in the nucleus (p = 0.023) and PA (p = 0.014), but not the anterior annulus (AA; p = 0.137). These results indicate in vivo disc deformation is level-dependent, and single-level anterior arthrodesis alters the compression–distraction deformation in the disc immediately superior to the arthrodesis. PMID:23861160

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

PubMed

Brophy, Carl M; Hoh, Daniel J

2018-06-01

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

Role of sediment size and biostratinomy on the development of biofilms in recent avian vertebrate remains

NASA Astrophysics Data System (ADS)

Peterson, Joseph E.; Lenczewski, Melissa E.; Clawson, Steven R.; Warnock, Jonathan P.

2017-04-01

Microscopic soft tissues have been identified in fossil vertebrate remains collected from various lithologies. However, the diagenetic mechanisms to preserve such tissues have remained elusive. While previous studies have described infiltration of biofilms in Haversian and Volkmann’s canals, biostratinomic alteration (e.g., trampling), and iron derived from hemoglobin as playing roles in the preservation processes, the influence of sediment texture has not previously been investigated. This study uses a Kolmogorov Smirnov Goodness-of-Fit test to explore the influence of biostratinomic variability and burial media against the infiltration of biofilms in bone samples. Controlled columns of sediment with bone samples were used to simulate burial and subsequent groundwater flow. Sediments used in this study include clay-, silt-, and sand-sized particles modeled after various fluvial facies commonly associated with fossil vertebrates. Extant limb bone samples obtained from Gallus gallus domesticus (Domestic Chicken) buried in clay-rich sediment exhibit heavy biofilm infiltration, while bones buried in sands and silts exhibit moderate levels. Crushed bones exhibit significantly lower biofilm infiltration than whole bone samples. Strong interactions between biostratinomic alteration and sediment size are also identified with respect to biofilm development. Sediments modeling crevasse splay deposits exhibit considerable variability; whole-bone crevasse splay samples exhibit higher frequencies of high-level biofilm infiltration, and crushed-bone samples in modeled crevasse splay deposits display relatively high frequencies of low-level biofilm infiltration. These results suggest that sediment size, depositional setting, and biostratinomic condition play key roles in biofilm infiltration in vertebrate remains, and may influence soft tissue preservation in fossil vertebrates.

An ancient look at UCP1.

PubMed

Klingenspor, Martin; Fromme, Tobias; Hughes, David A; Manzke, Lars; Polymeropoulos, Elias; Riemann, Tobias; Trzcionka, Magdalene; Hirschberg, Verena; Jastroch, Martin

2008-01-01

Brown adipose tissue serves as a thermogenic organ in placental mammals to defend body temperature in the cold by nonshivering thermogenesis. The thermogenic function of brown adipose tissue is enabled by several specialised features on the organ as well as on the cellular level, including dense sympathetic innervation and vascularisation, high lipolytic capacity and mitochondrial density and the unique expression of uncoupling protein 1 (UCP1). This mitochondrial carrier protein is inserted into the inner mitochondrial membrane and stimulates maximum mitochondrial respiration by dissipating proton-motive force as heat. Studies in knockout mice have clearly demonstrated that UCP1 is essential for nonshivering thermogenesis in brown adipose tissue. For a long time it had been presumed that brown adipose tissue and UCP1 emerged in placental mammals providing them with a unique advantage to survive in the cold. Our subsequent discoveries of UCP1 orthologues in ectotherm vertebrates and marsupials clearly refute this presumption. We can now initiate comparative studies on the structure-function relationships in UCP1 orthologues from different vertebrates to elucidate when during vertebrate evolution UCP1 gained the biochemical properties required for nonshivering thermogenesis.

Heterochronic shift in Hox-mediated activation of sonic hedgehog leads to morphological changes during fin development.

PubMed

Sakamoto, Koji; Onimaru, Koh; Munakata, Keijiro; Suda, Natsuno; Tamura, Mika; Ochi, Haruki; Tanaka, Mikiko

2009-01-01

We explored the molecular mechanisms of morphological transformations of vertebrate paired fin/limb evolution by comparative gene expression profiling and functional analyses. In this study, we focused on the temporal differences of the onset of Sonic hedgehog (Shh) expression in paired appendages among different vertebrates. In limb buds of chick and mouse, Shh expression is activated as soon as there is a morphological bud, concomitant with Hoxd10 expression. In dogfish (Scyliorhinus canicula), however, we found that Shh was transcribed late in fin development, concomitant with Hoxd13 expression. We utilized zebrafish as a model to determine whether quantitative changes in hox expression alter the timing of shh expression in pectoral fins of zebrafish embryos. We found that the temporal shift of Shh activity altered the size of endoskeletal elements in paired fins of zebrafish and dogfish. Thus, a threshold level of hox expression determines the onset of shh expression, and the subsequent heterochronic shift of Shh activity can affect the size of the fin endoskeleton. This process may have facilitated major morphological changes in paired appendages during vertebrate limb evolution.

Word aligned bitmap compression method, data structure, and apparatus

DOEpatents

Wu, Kesheng; Shoshani, Arie; Otoo, Ekow

2004-12-14

The Word-Aligned Hybrid (WAH) bitmap compression method and data structure is a relatively efficient method for searching and performing logical, counting, and pattern location operations upon large datasets. The technique is comprised of a data structure and methods that are optimized for computational efficiency by using the WAH compression method, which typically takes advantage of the target computing system's native word length. WAH is particularly apropos to infrequently varying databases, including those found in the on-line analytical processing (OLAP) industry, due to the increased computational efficiency of the WAH compressed bitmap index. Some commercial database products already include some version of a bitmap index, which could possibly be replaced by the WAH bitmap compression techniques for potentially increased operation speed, as well as increased efficiencies in constructing compressed bitmaps. Combined together, this technique may be particularly useful for real-time business intelligence. Additional WAH applications may include scientific modeling, such as climate and combustion simulations, to minimize search time for analysis and subsequent data visualization.

Epidural spread of iohexol following the use of air or saline in the 'loss of resistance' test.

PubMed

Iseri, Toshie; Nishimura, Ryohei; Nagahama, Shotaro; Mochizuki, Manabu; Nakagawa, Takayuki; Fujimoto, Yuka; Zhang, Di; Sasaki, Nobuo

2010-11-01

To compare, using CT epidurography, the cranial distribution of contrast after epidural injection when saline or air is used for the loss of resistance (LOR) technique in identifying the epidural space. Prospective, randomized, cross-over experimental study. Nine healthy adult Beagle dogs. Under general anaesthesia, a spinal needle (22-gauge, 70 mm) was inserted through the lumbosacral space, and the position in the epidural space confirmed using the LOR technique employing either 0.3 mL per dog of saline or of air. Epidurography using CT was performed before and 5, 10 and 20 minutes after epidural injection of 0.2 mL kg(-1) of iohexol. The cranial distribution of iohexol was recorded as the number of vertebral segments reached from the seventh lumbar vertebrae. The median values in vertebral segments of the cranial distribution at 5, 10 and 20 minutes after epidural injection were 19.5, 20.5 and 21.0 respectively with the saline treatment, and 12.0, 15.0 and 16.0 respectively in the air treatment. At all time points spread of contrast was significantly less with the air treatment. All dogs after air treatment had some air bubbles in the epidural space, and in seven, the spinal cord was moderately compressed by the air. No neurological complications were observed after recovery. The use of air for the LOR technique is associated with significantly less spread, uneven cranial distribution of the contrast medium and compression of the spinal cord. It is recommended that saline, and not air, should be used to identify the epidural space by this method. © 2010 The Authors. Veterinary Anaesthesia and Analgesia © 2010 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists.

Kyphoplasty with purified silicone VK100 (Elastoplasty) to treat spinal lytic lesions in cancer patients: A retrospective evaluation of 41 cases.

PubMed

Telera, Stefano; Pompili, Alfredo; Crispo, Francesco; Giovannetti, Maddalena; Pace, Andrea; Villani, Veronica; Fabi, Alessandra; Sperduti, Isabella; Raus, Laura

2018-06-15

Balloon Kyphoplasty (BKP) for vertebral compression fractures (VCFs) in cancer patients is more challenging than for osteoporotic ones. Cord compressions are frequent and the incidence of complications ten-fold greater. Polymethylmetacrylate (PMMA) is the gold standard material for BKP but has disadvantages: exothermic reaction, short working time, rapid solidification, absence of osteoconduction. VK100 is a mixture of Dimethyl Methylvinyl siloxane and Barium Sulphate. It is elastic, adhesive to bone, leaves 30 min before solidification without exothermic reaction, and shows a stiffness close to the intact vertebrae. The surgical procedure, called elastoplasty, is similar to a BKP. Clinical results obtained with this new silicone in pathological VCFs have been investigated. 41 cancer patients with symptomatic VCFs (70 vertebral bodies), underwent percutaneous and open elastoplasties. Post-operative leakages, pulmonary embolism (PE) and adjacent fractures were carefully evaluated with neuroimaging. KPS, VAS and Dennis Pain Score were calculated pre- post-operatively and at the last follow-up. The mean volume of silicone inserted in each vertebra was 3.8 cc. Complications included seven leakages (17%), two asymptomatic PE (4.3%) and 3 post-operative adjacent fractures (7.3%). Median follow-up was 29 months. A significant improvement was observed in KPS, VAS and Dennis Pain Score (p < .0001). The 1-yr survival rate was 76.9%. Elastoplasty appears a safe and effective palliative treatment of VCFs in oncologic patients. Useful qualities of VK100 are the lack of exothermic reaction and the wider working window. The influence of biomechanical properties of silicone on reduction of adjacent level fractures requires further investigations. Copyright © 2018. Published by Elsevier B.V.

Analysis of risk factors causing short-term cement leakages and long-term complications after percutaneous kyphoplasty for osteoporotic vertebral compression fractures.

PubMed

Gao, Chang; Zong, Min; Wang, Wen-Tao; Xu, Lei; Cao, Da; Zou, Yue-Fen

2018-05-01

Background Percutaneous kyphoplasty (PKP) is a common treatment modality for painful osteoporotic vertebral compression fractures (OVCFs). Pre- and postoperative identification of risk factors for cement leakage and follow-up complications would therefore be helpful but has not been systematically investigated. Purpose To evaluate pre- and postoperative risk factors for the occurrence of short-term cement leakages and long-term complications after PKP for OVCFs. Material and Methods A total of 283 vertebrae with PKP in 239 patients were investigated. Possible risk factors causing cement leakage and complications during follow-up periods were retrospectively assessed using multivariate analysis. Cement leakage in general, three fundamental leakage types, and complications during follow-up period were directly identified through postoperative computed tomography (CT). Results Generally, the presence of cortical disruption ( P = 0.001), large volume of cement ( P = 0.012), and low bone mineral density (BMD) ( P = 0.002) were three strong predictors for cement leakage. While the presence of intravertebral cleft and Schmorl nodes ( P = 0.045 and 0.025, respectively) were respectively identified as additional risk factors for paravertebral and intradiscal subtype of cortical (C-type) leakages. In terms of follow-up complications, occurrence of cortical leakage was a strong risk factor both for new VCFs ( P = 0.043) and for recompression ( P = 0.004). Conclusion The presence of cortical disruption, large volume of cement, and low BMD of treated level are general but strong predictors for cement leakage. The presence of intravertebral cleft and Schmorl nodes are additional risk factors for cortical leakage. During follow-up, the occurrence of C-type leakage is a strong risk factor, for both new VCFs and recompression.

Thoracolumbar spine fractures in frontal impact crashes.

PubMed

Pintar, Frank A; Yoganandan, Narayan; Maiman, Dennis J; Scarboro, Mark; Rudd, Rodney W

2012-01-01

There is currently no injury assessment for thoracic or lumbar spine fractures in the motor vehicle crash standards throughout the world. Compression-related thoracolumbar fractures are occurring in frontal impacts and yet the mechanism of injury is poorly understood. The objective of this investigation was to characterize these injuries using real world crash data from the US-DOT-NHTSA NASS-CDS and CIREN databases. Thoracic and lumbar AIS vertebral body fracture codes were searched for in the two databases. The NASS database was used to characterize population trends as a function of crash year and vehicle model year. The CIREN database was used to examine a case series in more detail. From the NASS database there were 2000-4000 occupants in frontal impacts with thoracic and lumbar vertebral body fractures per crash year. There was an increasing trend in incidence rate of thoracolumbar fractures in frontal impact crashes as a function of vehicle model year from 1986 to 2008; this was not the case for other crash types. From the CIREN database, the thoracolumbar spine was most commonly fractured at either the T12 or L1 level. Major, burst type fractures occurred predominantly at T12, L1 or L5; wedge fractures were most common at L1. Most CIREN occupants were belted; there were slightly more females involved; they were almost all in bucket seats; impact location occurred approximately half the time on the road and half off the road. The type of object struck also seemed to have some influence on fractured spine level, suggesting that the crash deceleration pulse may be influential in the type of compression vector that migrates up the spinal column. Future biomechanical studies are required to define mechanistically how these fractures are influenced by these many factors.

Ulmus davidiana extract improves lumbar vertebral parameters in ovariectomized osteopenic rats

PubMed Central

Zhuang, Xinming; Fu, Changfeng; Liu, Wanguo; Wang, Yuanyi; Xu, Feng; Zhang, Qi; Liu, Yadong; Liu, Yi

2016-01-01

The aim of this study was to determine the skeletal effect of total ethanolic extract from the stem-bark of Ulmus davidiana (UDE) in a rat model of postmenopausal bone loss. Effective dose of UDE was determined in adult female Sprague-Dawley (SD) rats by measuring bone regeneration at fracture site. UDE (250 mg/kg p.o.) was administered to ovariectomized (OVX) osteopenic SD rats for 12 weeks. OVX rats treated with vehicle or 17β-estradiol, and sham-operated rats treated with vehicle served as various controls. Bone mineral density (BMD), microarchitecture, biomechanical strength, turnover markers, and uterotrophic effect were studied. Bioactive markers in UDE were analyzed by HPLC. Human osteoblasts was used to study the effect of compounds on differentiation by alkaline phosphase assay. One-way ANOVA was used to test significance of effects. OVX+UDE group showed BMD, microarchitectural parameters and compressive strength at lumbar vertebra (L5) comparable to sham. At proximal femur, OVX+UDE group exhibited significantly higher BMD, better microarchitecture and compressive strength compared with OVX+vehicle. OVX-induced decrease in Ca/P ratio was completely restored at both skeletal sites by UDE treatment. Serum procollagen N-terminal propeptide and carboxy-terminal collagen crosslinks were respectively higher and lower in OVX+UDE group compared with OVX+vehicle group. Osteogenic genes were upregulated in L5 and anti-resorptive genes were suppressed in proximal femur of OVX+UDE group compared with OVX+vehicle. UDE had no uterine estrogenicity. Analysis of markers yielded two osteogenic isoforms of catechin. In conclusion, UDE completely restored vertebral trabecular bones and strength in osteopenic rats by an osteogenic mechanism and prevented bone loss at proximal femur. PMID:27158327

The polymethyl methacrylate cervical cage for treatment of cervical disk disease Part III. Biomechanical properties.

PubMed

Chen, Jyi-Feng; Lee, Shih-Tseng

2006-10-01

In a previous article, we used the PMMA cervical cage in the treatment of single-level cervical disk disease and the preliminary clinical results were satisfactory. However, the mechanical properties of the PMMA cage were not clear. Therefore, we designed a comparative in vitro biomechanical study to determine the mechanical properties of the PMMA cage. The PMMA cervical cage and the Solis PEEK cervical cage were compressed in a materials testing machine to determine the mechanical properties. The compressive yield strength of the PMMA cage (7030 +/- 637 N) was less than that of the Solis polymer cervical cage (8100 +/- 572 N). The ultimate compressive strength of the PMMA cage (8160 +/- 724 N) was less than that of the Solis cage (9100 +/- 634 N). The stiffness of the PMMA cervical cage (8106 +/- 817 N/mm) was greater than that of the Solis cage (6486 +/- 530 N/mm). The elastic modulus of the PMMA cage (623 +/- 57 MPa) was greater than that of the Solis cage (510 +/- 42 MPa). The elongation of PMMA cage (43.5 +/- 5.7%) was larger than that of the Solis cage (36.1 +/- 4.3%). Although the compressive yield strength and ultimate compressive strength of the PMMA cervical cage were less than those of the Solis polymer cage, the mechanical properties are better than those of the cervical vertebral body. The PMMA cage is strong and safe for use as a spacer for cervical interbody fusion. Compared with other cage materials, the PMMA cage has many advantages and no obvious failings at present. However, the PMMA cervical cage warrants further long-term clinical study.

Sensitivity studies of pediatric material properties on juvenile lumbar spine responses using finite element analysis.

PubMed

Jebaseelan, D Davidson; Jebaraj, C; Yoganandan, Narayan; Rajasekaran, S; Kanna, Rishi M

2012-05-01

The objective of the study was to determine the sensitivity of material properties of the juvenile spine to its external and internal responses using a finite element model under compression, and flexion-extension bending moments. The methodology included exercising the 8-year-old juvenile lumbar spine using parametric procedures. The model included the vertebral centrum, growth plates, laminae, pedicles, transverse processes and spinous processes; disc annulus and nucleus; and various ligaments. The sensitivity analysis was conducted by varying the modulus of elasticity for various components. The first simulation was done using mean material properties. Additional simulations were done for each component corresponding to low and high material property variations. External displacement/rotation and internal stress-strain responses were determined under compression and flexion-extension bending. Results indicated that, under compression, disc properties were more sensitive than bone properties, implying an elevated role of the disc under this mode. Under flexion-extension moments, ligament properties were more dominant than the other components, suggesting that various ligaments of the juvenile spine play a key role in modulating bending behaviors. Changes in the growth plate stress associated with ligament properties explained the importance of the growth plate in the pediatric spine with potential implications in progressive deformities.

Reduction in nerve root compression by the nucleus pulposus after Feng's Spinal Manipulation☆

PubMed Central

Feng, Yu; Gao, Yan; Yang, Wendong; Feng, Tianyou

2013-01-01

Ninety-four patients with lumbar intervertebral disc herniation were enrolled in this study. Of these, 48 were treated with Feng's Spinal Manipulation, hot fomentation, and bed rest (treatment group). The remaining 46 patients were treated with hot fomentation and bed rest only (control group). After 3 weeks of treatment, clinical parameters including the angle of straight-leg raising, visual analogue scale pain score, and Japanese Orthopaedic Association score for low back pain were improved. The treatment group had significantly better improvement in scores than the control group. Magnetic resonance myelography three-dimensional reconstruction imaging of the vertebral canal demonstrated that filling of the compressed nerve root sleeve with cerebrospinal fluid increased significantly in the treatment group. The diameter of the nerve root sleeve was significantly larger in the treatment group than in the control group. However, the sagittal diameter index of the herniated nucleus pulposus and the angle between the nerve root sleeve and the thecal sac did not change significantly in either the treatment or control groups. The effectiveness of Feng's Spinal Manipulation for the treatment of symptoms associated with lumbar intervertebral disc herniation may be attributable to the relief of nerve root compression, without affecting the herniated nucleus pulposus or changing the morphology or position of the nerve root. PMID:25206408

Finite element analysis and cadaveric cinematic analysis of fixation options for anteriorly implanted trabecular metal interbody cages.

PubMed

Berjano, Pedro; Blanco, Juan Francisco; Rendon, Diego; Villafañe, Jorge Hugo; Pescador, David; Atienza, Carlos Manuel

2015-11-01

To assess, with finite element analysis and an in vitro biomechanical study in cadaver, whether the implementation of an anterior interbody cage made of hedrocel with nitinol shape memory staples in compression increases the stiffness of the stand-alone interbody cage and to compare these constructs' stiffness to other constructs common in clinical practice. A biomechanical study with a finite element analysis and cadaveric testing assessed the stiffness of different fixation modes for the L4-L5 functional spinal unit: intact spine, destabilized spine with discectomy, posterior pedicle-screw fixation, anterior stand-alone interbody cage, anterior interbody cage with bilateral pedicle screws and anterior interbody cage with two shape memory staples in compression. These modalities of vertebral fixation were compared in four loading modes (flexion, extension, lateral bending, and axial rotation). The L4-L5 spinal unit with an anterior interbody cage and two staples was stiffer than the stand-alone cage. The construct stiffness was similar to that of a model of posterior pedicular stabilization. The stiffness was lower than that of the anterior cage plus bilateral pedicle-screw fixation. The use of an anterior interbody implant with shape memory staples in compression may be an alternative to isolated posterior fixation and to anterior isolated implants, with increased stiffness.

Progenitors of the protochordate ocellus as an evolutionary origin of the neural crest

PubMed Central

2013-01-01

The neural crest represents a highly multipotent population of embryonic stem cells found only in vertebrate embryos. Acquisition of the neural crest during the evolution of vertebrates was a great advantage, providing Chordata animals with the first cellular cartilage, bone, dentition, advanced nervous system and other innovations. Today not much is known about the evolutionary origin of neural crest cells. Here we propose a novel scenario in which the neural crest originates from neuroectodermal progenitors of the pigmented ocelli in Amphioxus-like animals. We suggest that because of changes in photoreception needs, these multipotent progenitors of photoreceptors gained the ability to migrate outside of the central nervous system and subsequently started to give rise to neural, glial and pigmented progeny at the periphery. PMID:23575111

Osteogenesis imperfecta presenting as aneurysmal subarachnoid haemorrhage in a 53-year-old man

PubMed Central

Kaliaperumal, Chandrasekaran; Walsh, Tom; Balasubramanian, Chandramouli; Wyse, Gerry; Fanning, Noel; Kaar, George

2011-01-01

The authors describe a case of aneurysmal subarachnoid haemorrhage in a 53-year-old man with background of osteogenesis imperfecta (OI). CT brain revealed diffuse subarachnoid haemorrhage (SAH) and cerebral angiogram subsequently confirmed vertebral artery aneurysm rupture leading to SAH. To the authors knowledge this is the first case of vertebral artery aneurysmal SAH described in OI. A previously undiagnosed OI was confirmed by genetic analysis (COL1A1 gene mutation). This aneurysm was successfully treated by endovascular route. Post interventional treatment patient developed stroke secondary to vasospasm. Communicating hydrocephalus, which developed in the process of management, was successfully treated with ventriculo-peritoneal shunt. The aetio-pathogenesis and management of this condition is described. The authors have reviewed the literature and genetic basis of this disease. PMID:22674700

Genomic Identification and Analysis of Shared Cis-regulator Elements in a Developmentally Critical homeobox Cluster

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

Chris Amemiya

2003-04-01

The goals of this project were to isolate, characterize, and sequence the Dlx3/Dlx7 bigene cluster from twelve different species of mammals. The Dlx3 and Dlx7 genes are known to encode homeobox transcription factors involved in patterning of structures in the vertebrate jaw as well as vertebrate limbs. Genomic sequences from the respective taxa will subsequently be compared in order to identify conserved non-coding sequences that are potential cis-regulatory elements. Based on the comparisons they will fashion transgenic mouse experiments to functionally test the strength of the potential cis-regulatory elements. A goal of the project is to attempt to identify thosemore » elements that may function in coordinately regulating both Dlx3 and Dlx7 functions.« less

[Establishment and validation of normal human L1-L5 lumbar three-dimensional finite element model].

PubMed

Zhu, Zhenqi; Liu, Chenjun; Wang, Jiefu; Wang, Kaifeng; Huang, Zhixin; Wang, Weida; Liu, Haiying

2014-10-14

To create and validate a L1-L5 lumbar three-dimensional finite element model. The L1-L5 lumbar spines of a male healthy volunteer were scanned with computed tomography (CT). And a L1-L5 lumbar three-dimensional finite element model was created with the aid of software packages of Mimics, Geomagic and Ansys. Then border conditions were set, unit type was determined, finite element mesh was divided and a model was established for loading and calculating. Average model stiffness under the conditions of flexion, extension, lateral bending and axial rotation was calculated and compared with the outcomes of former articles for validation. A normal human L1-L5 lumbar three-dimensional finite element model was established to include 459 340 elements and 661 938 nodes. After constraining the inferior endplate of L5 vertebral body, 500 kg × m × s⁻² compressive loading was imposed averagely on the superior endplate of L1 vertebral body. Then 10 kg × m² × s⁻² moment simulating flexion, extension, lateral bending and axial rotation were imposed on the superior endplate of L1 vertebral body. Eventually the average stiffness of all directions was calculated and it was similar to the outcomes of former articles. The L1-L5 lumbar three-dimensional finite element model is validated so that it may used with biomechanical simulation and analysis of normal or surgical models.

A systematic approach to vertebral hemangioma.

PubMed

Gaudino, Simona; Martucci, Matia; Colantonio, Raffaella; Lozupone, Emilio; Visconti, Emiliano; Leone, Antonio; Colosimo, Cesare

2015-01-01

Vertebral hemangiomas (VHs) are a frequent and often incidental finding on computed tomography (CT) and magnetic resonance (MR) imaging of the spine. When their imaging appearance is "typical" (coarsened vertical trabeculae on radiographic and CT images, hyperintensity on T1- and T2-weighted MR images), the radiological diagnosis is straightforward. Nonetheless, VHs might also display an "atypical" appearance on MR imaging because of their histological features (amount of fat, vessels, and interstitial edema). Although the majority of VHs are asymptomatic and quiescent lesions, they can exhibit active behaviors, including growing quickly, extending beyond the vertebral body, and invading the paravertebral and/or epidural space with possible compression of the spinal cord and/or nerve roots ("aggressive" VHs). These "atypical" and "aggressive" VHs are a radiological challenge since they can mimic primary bony malignancies or metastases. CT plays a central role in the workup of atypical VHs, being the most appropriate imaging modality to highlight the polka-dot appearance that is representative of them. When aggressive VHs are suspected, both CT and MR are needed. MR is the best imaging modality to characterize the epidural and/or soft-tissue component, helping in the differential diagnosis. Angiography is a useful imaging adjunct for evaluating and even treating aggressive VHs. The primary objectives of this review article are to summarize the clinical, pathological, and imaging features of VHs, as well as the treatment options, and to provide a practical guide for the differential diagnosis, focusing on the rationale assessment of the findings from radiography, CT, and MR imaging.

A case report of spondylectomy with circumference reconstruction for aggressive vertebral hemangioma covering the whole cervical spine (C4) with progressive spinal disorder.

PubMed

Nakahara, Masayuki; Nishida, Kenki; Kumamoto, Shinji; Hijikata, Yasukazu; Harada, Kei

2017-05-01

To describe the surgical experience of spondylectomy and spinal reconstruction for aggressive vertebral hemangioma (VH) induced at the C4 vertebra. No reports have described surgical strategy in cases covering an entire cervical vertebra presenting with progressive myelopathy. A 28-year-old man presented with rapidly progressing skilled motor dysfunction and gait disorder. The Japanese Orthopedic Association (JOA) score was 6. Radiography showed a honeycomb appearance for the entire circumference of the C4 vertebra. Spinal computed tomography and magnetic resonance imaging showed vertebral tumor with extraosseous extension causing spinal cord compression. Results of diagnostic imaging were strongly suggestive of VH. Transarterial embolization of the spinal body branch was performed first to decrease intraoperative bleeding, followed by cervical posterior fixation to stabilize the unstable segment and excision biopsy to obtain a definitive diagnosis. After definitive diagnosis of cavernous hemangioma, two-stage surgery (anterior and posterior) was performed to complete total spondylectomy and 360° spinal reconstruction. Despite multiple operations, JOA scores were 8.5 after posterior fixation, 10.5 after anterior surgery, 11 after final surgery and 16 on postoperative day 90. The patient acquired excellent clinical results without complications and returned to society. The present three-stage surgery comprising fixation, biopsy, and final spondylectomy with circumferential fusion from anterior and posterior approaches may offer a useful choice for aggressive VH covering the entire cervical spine with rapidly progressive myelopathy.

Intravenous pamidronate treatment of infants with severe osteogenesis imperfecta.

PubMed

Aström, Eva; Jorulf, Håkan; Söderhäll, Stefan

2007-04-01

Children with the severe forms of osteogenesis imperfecta have in several studies been treated with intravenous pamidronate, but there are only few reports of the effect of early treatment. To evaluate the effect of treatment started in infancy. In a prospective observational study, with a historic control group, intravenous disodium pamidronate (APD) was given as monthly infusions to 11 children with osteogenesis imperfecta aged 3-13 (median 3.6) months, who had severe osteogenesis imperfecta with congenital bowing of the femora and vertebral compression fractures. During treatment of children aged between 3 and 6 (median 4.5) years, dual-energy x ray absorptiometry measurements of the lumbar spine showed a gradual increase in bone density. Bone metabolism parameters in serum (alkaline phosphatase, osteocalcin, procollagen 1 carboxy-terminal peptide, collagen 1 teleopeptide) and in urine (deoxypyridinoline) indicated a decrease in bone turnover. An improvement of mobility was seen and at the latest recording, at the age of 3.3-6.5 (median 4.8) years, the children could all walk. Vertebral remodelling was seen, with increased vertebral height, and no child developed scoliosis, kyphosis or basilar impression. All children required femoral intramedullar rods for fractures, and five needed tibial rodding for extreme curvatures that prevented functional standing and walking. No adverse effects were seen on growth, fracture healing or blood chemistry. APD is an efficient symptomatic treatment for infants with severe osteogenesis imperfecta, but additional orthopaedic surgery is often needed. Early treatment may prevent scoliosis and basilar impression. Long-term follow-up is important.

Dissecting the determinants of light sensitivity in amphioxus microvillar photoreceptors: possible evolutionary implications for melanopsin signaling.

PubMed

Ferrer, Camilo; Malagón, Gerardo; Gomez, María Del Pilar; Nasi, Enrico

2012-12-12

Melanopsin, a photopigment related to the rhodopsin of microvillar photoreceptors of invertebrates, evolved in vertebrates to subserve nonvisual light-sensing functions, such as the pupillary reflex and entrainment of circadian rhythms. However, vertebrate circadian receptors display no hint of a microvillar specialization and show an extremely low light sensitivity and sluggish kinetics. Recently in amphioxus, the most basal chordate, melanopsin-expressing photoreceptors were characterized; these cells share salient properties with both rhabdomeric photoreceptors of invertebrates and circadian receptors of vertebrates. We used electrophysiology to dissect the gain of the light-transduction process in amphioxus and examine key features that help outline the evolutionary transition toward a sensor optimized to report mean ambient illumination rather than mediating spatial vision. By comparing the size of current fluctuations attributable to single photon melanopsin isomerizations with the size of single-channels activated by light, we concluded that the gain of the transduction cascade is lower than in rhabdomeric receptors. In contrast, the expression level of melanopsin (gauged by measuring charge displacements during photo-induced melanopsin isomerization) is comparable with that of canonical visual receptors. A modest amplification in melanopsin-using receptors is therefore apparent in early chordates; the decrease in photopigment expression-and loss of the anatomical correlates-observed in vertebrates subsequently enabled them to attain the low photosensitivity tailored to the role of circadian receptors.

The evolution of vertebrate somatostatin receptors and their gene regions involves extensive chromosomal rearrangements

PubMed Central

2012-01-01

Background Somatostatin and its related neuroendocrine peptides have a wide variety of physiological functions that are mediated by five somatostatin receptors with gene names SSTR1-5 in mammals. To resolve their evolution in vertebrates we have investigated the SSTR genes and a large number of adjacent gene families by phylogeny and conserved synteny analyses in a broad range of vertebrate species. Results We find that the SSTRs form two families that belong to distinct paralogons. We observe not only chromosomal similarities reflecting the paralogy relationships between the SSTR-bearing chromosome regions, but also extensive rearrangements between these regions in teleost fish genomes, including fusions and translocations followed by reshuffling through intrachromosomal rearrangements. These events obscure the paralogy relationships but are still tractable thanks to the many genomes now available. We have identified a previously unrecognized SSTR subtype, SSTR6, previously misidentified as either SSTR1 or SSTR4. Conclusions Two ancestral SSTR-bearing chromosome regions were duplicated in the two basal vertebrate tetraploidizations (2R). One of these ancestral SSTR genes generated SSTR2, -3 and -5, the other gave rise to SSTR1, -4 and -6. Subsequently SSTR6 was lost in tetrapods and SSTR4 in teleosts. Our study shows that extensive chromosomal rearrangements have taken place between related chromosome regions in teleosts, but that these events can be resolved by investigating several distantly related species. PMID:23194088

Uprobe: a genome-wide universal probe resource for comparative physical mapping in vertebrates.

PubMed

Kellner, Wendy A; Sullivan, Robert T; Carlson, Brian H; Thomas, James W

2005-01-01

Interspecies comparisons are important for deciphering the functional content and evolution of genomes. The expansive array of >70 public vertebrate genomic bacterial artificial chromosome (BAC) libraries can provide a means of comparative mapping, sequencing, and functional analysis of targeted chromosomal segments that is independent and complementary to whole-genome sequencing. However, at the present time, no complementary resource exists for the efficient targeted physical mapping of the majority of these BAC libraries. Universal overgo-hybridization probes, designed from regions of sequenced genomes that are highly conserved between species, have been demonstrated to be an effective resource for the isolation of orthologous regions from multiple BAC libraries in parallel. Here we report the application of the universal probe design principal across entire genomes, and the subsequent creation of a complementary probe resource, Uprobe, for screening vertebrate BAC libraries. Uprobe currently consists of whole-genome sets of universal overgo-hybridization probes designed for screening mammalian or avian/reptilian libraries. Retrospective analysis, experimental validation of the probe design process on a panel of representative BAC libraries, and estimates of probe coverage across the genome indicate that the majority of all eutherian and avian/reptilian genes or regions of interest can be isolated using Uprobe. Future implementation of the universal probe design strategy will be used to create an expanded number of whole-genome probe sets that will encompass all vertebrate genomes.

The Optimal Volume Fraction in Percutaneous Vertebroplasty Evaluated by Pain Relief, Cement Dispersion, and Cement Leakage: A Prospective Cohort Study of 130 Patients with Painful Osteoporotic Vertebral Compression Fracture in the Thoracolumbar Vertebra.

PubMed

Sun, Hai-Bo; Jing, Xiao-Shan; Liu, Yu-Zeng; Qi, Ming; Wang, Xin-Kuan; Hai, Yong

2018-06-01

To probe the relationship among cement volume/fraction, imaging features of cement distribution, and pain relief and then to evaluate the optimal volume during percutaneous vertebroplasty. From January 2014 to January 2017, a total of 130 patients eligible for inclusion criteria were enrolled in this prospective cohort study. According to the different degrees of pain relief, cement leakage, and cement distribution, all patients were allocated to 2 groups. Clinical and radiologic characteristics were assessed to identify independent factors influencing pain relief, cement leakage, and cement distribution, including age, sex, fracture age, bone mineral density, operation time, fracture level, fracture type, modified semiquantitative severity grade, intravertebral cleft, cortical disruption in the vertebral wall, endplate disruption, type of nutrient foramen, fractured vertebral body volume, intravertebral cement volume, and volume fraction. A receiver operating characteristic curve was used to analyze the diagnostic value of the cement volume/fraction and then to obtain the optional cut-off value. The preoperative visual analog scale scores in the responders versus nonresponders patient groups were 7.37 ± 0.61 versus 7.87 ± 0.92 and the postoperative VAS scores in the responders versus nonresponders were 2.04 ± 0.61 versus 4.33 ± 0.49 at 1 week. There were no independent factors influencing pain relief. There were 95 (73.08%) patients who experienced cement leakage, and cortical disruption in the vertebral wall and cement fraction percentage were identified as independent risk factors by binary logistic regression analysis (adjusted odds ratio [OR] 2.935, 95% confidence interval [95% CI] 1.214-7.092, P = 0.017); (adjusted OR 1.134, 95% CI 1.026-1.254, P = 0.014). The area under the receiver-operating characteristic curve of volume fraction (VF%) was 0.658 (95% CI 0.549-0.768, P = 0.006 < 0.05). The cut-off value of VF% for cement leakage was 21.545%, with a sensitivity of 69.50% and a specificity of 60.00%. The incidence of favorable cement distribution was 74.62% (97/130), and VF% were identified as independent protective factors (adjusted OR 1.185, 95% CI 1.067-1.317, P = 0.002) The area under the receiver-operating characteristic curve of VF% was 0.686 (95% CI 0.571-0.802, P = 0.001 < 0.05). The cut-off value of VF% to reach a favorable cement distribution was 19.78%, with a sensitivity of 86.60% and a specificity of 51.50%. In osteoporotic vertebral compression fracture with mild/moderate fracture severity at the single thoracolumbar level, the intravertebral cement volume of 4-6 mL could relieve pain rapidly. The optimal VF% was 19.78%, which could achieve satisfactory cement distribution. With the increase of VF%, the incidence of cement leakage would also increase. Copyright © 2018 Elsevier Inc. All rights reserved.

Plastic Deformation of Magnesium Alloy Subjected to Compression-First Cyclic Loading

NASA Astrophysics Data System (ADS)

Lee, Soo Yeol; Gharghouri, Michael A.; Root, John H.

In-situ neutron diffraction has been employed to study the deformation mechanisms in a precipitation-hardened and extruded Mg-8.5wt.% Al alloy subjected to compression followed by reverse tension. The starting texture is such that the basal poles of most grains are oriented normal to the extrusion axis and a small portion of grains are oriented with the basal pole parallel to the extrusion axis. Diffraction peak intensities for several grain orientations monitored in-situ during deformation show that deformation twinning plays an important role in the elastic-plastic transition and subsequent plastic deformation behavior. Significant non-linear behavior is observed during unloading after compression and appears to be due to detwinning. This effect is much stronger after compressive loading than after tensile loading.

The Structure and Mechanical Properties of High-Strength Bulk Ultrafine-Grained Cobalt Prepared Using High-Energy Ball Milling in Combination with Spark Plasma Sintering

PubMed Central

Marek, Ivo; Vojtěch, Dalibor; Michalcová, Alena; Kubatík, Tomáš František

2016-01-01

In this study, bulk ultrafine-grained and micro-crystalline cobalt was prepared using a combination of high-energy ball milling and subsequent spark plasma sintering. The average grain sizes of the ultrafine-grained and micro-crystalline materials were 200 nm and 1 μm, respectively. Mechanical properties such as the compressive yield strength, the ultimate compressive strength, the maximum compressive deformation and the Vickers hardness were studied and compared with those of a coarse-grained as-cast cobalt reference sample. The bulk ultrafine-grained sample showed an ultra-high compressive yield strength that was greater than 1 GPa, which is discussed with respect to the preparation technique and a structural investigation. PMID:28773514

Pedicle distraction increases intervertebral and spinal canal area in a cadaver and bone model

PubMed Central

Hughes, Matthew; Papadakos, Nikolaos; Bishop, Tim; Bernard, Jason

2018-01-01

Introduction: Lumbar spinal stenosis is degenerative narrowing of the spinal canal and/or intervertebral foramen causing compression of the spinal cord and nerve roots. Traditional decompression techniques can often cause significant trauma and vertebral instability. This paper evaluates a method of increasing pedicle length to decompress the spinal and intervertebral foramen, which could be done minimally invasive. Methods: Three Sawbone (Sawbones Europe, Sweden) and 1 cadaveric lumbar spine underwent bilateral pedicle distraction at L4. A pedicle channel was drilled between the superior articular process and transverse process into the vertebral body. The pedicles underwent osteotomy at the midpoint. Screws were inserted bilaterally and fixated distraction of 0 mm, 2 mm, 4 mm and 6 mm. CT images were taken at each level of distraction. Foramen area was measured in the sagittal plane at L3/4. Spinal canal area was measured at L4 in the axial images. The cadaver was used to evaluate safety of osteotomy and soft tissue interactions preventing distraction. Statistical analysis was by student paired t-test and Pearson rank test. Results: Increasing distraction led to greater Spinal canal area. From 4.27 cm2 to 5.72 cm2 (p = 0.002) with 6 mm distraction. A Maximal increase of 34.1%. Vertebral foramen area also increased with increasing pedicle distraction. From 2.43 cm2 to 3.22 cm2 (p = 0.022) with 6 mm distraction. A maximal increase of 32.3%. The cadaver spinal canal increased in area by 21.7%. The vertebral foramen increased in area by 36.2% (left) and 22.6% (right). Discussion: For each increase in pedicle distraction the area of the spinal and vertebral foramen increases. Pedicle distraction could potentially be used to alleviate spinal stenosis and root impingement. A potential osteotomy plane could be at the midpoint of the pedicle with minimal risk to nerve roots and soft tissue restrictions to prevent distraction. PMID:29727270

Pedicle distraction increases intervertebral and spinal canal area in a cadaver and bone model.

PubMed

Hughes, Matthew; Papadakos, Nikolaos; Bishop, Tim; Bernard, Jason

2018-01-01

Lumbar spinal stenosis is degenerative narrowing of the spinal canal and/or intervertebral foramen causing compression of the spinal cord and nerve roots. Traditional decompression techniques can often cause significant trauma and vertebral instability. This paper evaluates a method of increasing pedicle length to decompress the spinal and intervertebral foramen, which could be done minimally invasive. Three Sawbone (Sawbones Europe, Sweden) and 1 cadaveric lumbar spine underwent bilateral pedicle distraction at L4. A pedicle channel was drilled between the superior articular process and transverse process into the vertebral body. The pedicles underwent osteotomy at the midpoint. Screws were inserted bilaterally and fixated distraction of 0 mm, 2 mm, 4 mm and 6 mm. CT images were taken at each level of distraction. Foramen area was measured in the sagittal plane at L3/4. Spinal canal area was measured at L4 in the axial images. The cadaver was used to evaluate safety of osteotomy and soft tissue interactions preventing distraction. Statistical analysis was by student paired t-test and Pearson rank test. Increasing distraction led to greater Spinal canal area. From 4.27 cm 2 to 5.72 cm 2 (p = 0.002) with 6 mm distraction. A Maximal increase of 34.1%. Vertebral foramen area also increased with increasing pedicle distraction. From 2.43 cm 2 to 3.22 cm 2 (p = 0.022) with 6 mm distraction. A maximal increase of 32.3%. The cadaver spinal canal increased in area by 21.7%. The vertebral foramen increased in area by 36.2% (left) and 22.6% (right). For each increase in pedicle distraction the area of the spinal and vertebral foramen increases. Pedicle distraction could potentially be used to alleviate spinal stenosis and root impingement. A potential osteotomy plane could be at the midpoint of the pedicle with minimal risk to nerve roots and soft tissue restrictions to prevent distraction. © The Authors, published by EDP Sciences, 2018.

Effect of sintering temperature on the microstructure and properties of foamed glass-ceramics prepared from high-titanium blast furnace slag and waste glass

NASA Astrophysics Data System (ADS)

Chen, Chang-hong; Feng, Ke-qin; Zhou, Yu; Zhou, Hong-ling

2017-08-01

Foamed glass-ceramics were prepared via a single-step sintering method using high-titanium blast furnace slag and waste glass as the main raw materials The influence of sintering temperature (900-1060°C) on the microstructure and properties of foamed glass-ceramics was studied. The results show that the crystal shape changed from grainy to rod-shaped and finally turned to multiple shapes as the sintering temperature was increased from 900 to 1060°C. With increasing sintering temperature, the average pore size of the foamed glass-ceramics increased and subsequently decreased. By contrast, the compressive strength and the bulk density decreased and subsequently increased. An excessively high temperature, however, induced the coalescence of pores and decreased the compressive strength. The optimal properties, including the highest compressive strength (16.64 MPa) among the investigated samples and a relatively low bulk density (0.83 g/cm3), were attained in the case of the foamed glass-ceramics sintered at 1000°C.

Acute lower extremity paralysis after lower extremity endovascular intervention.

PubMed

Öztürk, Semi; Kalyoncuoğlu, Muhsin; Durmuş, Gündüz; Topçu, Adem; Can, Mehmet

2017-04-01

A 61-year-old man underwent successful percutaneous revascularization of both lower limbs with multiple stent implantations. Paralysis of right lower limb was noticed after completion of procedure when transferring the patient from angiography table. Since hematoma compressing lumbosacral neural plexus could be a fatal complication, computed tomography (CT) image was taken. CT showed bulge of distended bladder compressing stent struts. Following placement of Foley catheter, condition improved and he was subsequently discharged uneventfully.

Trans-arterial Onyx Embolization of a Functional Thoracic Paraganglioma

PubMed Central

Chacón-Quesada, Tatiana; Maud, Alberto; Ramos-Duran, Luis; Torabi, Alireza; Fitzgerald, Tamara; Akle, Nassim; Cruz Flores, Salvador; Trier, Todd

2015-01-01

Paragangliomas are rare tumors of the endocrine system. They are highly vascular and in some cases hormonally active, making their management challenging. Although there is strong evidence of the safety and effectiveness of preoperative embolization in the management of spinal tumors, only five cases have been reported in the setting of thoracic paragangliomas. We present the case of a 19-year-old man with a large, primary, functional, malignant paraganglioma of the thoracic spine causing a vertebral fracture and spinal cord compression. To our knowledge this is the first report of preoperative trans-arterial balloon augmented Onyx embolization of a thoracic paraganglioma. PMID:25763296

New Daily Persistent Headache Caused by a Multinodular Goiter and Headaches Associated With Thyroid Disease.

PubMed

Evans, Randolph W; Timm, Josefine S

2017-02-01

A 33-year-old female is presented with the first case to our knowledge of new daily persistent headache (NDPH) with a large right benign non-toxic multinodular goiter causing carotid and vertebral compression with complete resolution of the headache immediately after thyroidectomy. Although this may be quite rare, hypothyroidism or hyperthyroidism causing NDPH, migraine, or an exacerbation of pre-existing migraine is not. Clinicians should consider routinely obtaining serum thyroid-stimulating hormone (TSH) and free T4 in patients with new onset frequent headaches or an exacerbation of prior primary headaches. © 2016 American Headache Society.

Ovary transcriptome profiling via artificial intelligence reveals a transcriptomic fingerprint predicting egg quality in striped bass, Morone saxatilis.

PubMed

Chapman, Robert W; Reading, Benjamin J; Sullivan, Craig V

2014-01-01

Inherited gene transcripts deposited in oocytes direct early embryonic development in all vertebrates, but transcript profiles indicative of embryo developmental competence have not previously been identified. We employed artificial intelligence to model profiles of maternal ovary gene expression and their relationship to egg quality, evaluated as production of viable mid-blastula stage embryos, in the striped bass (Morone saxatilis), a farmed species with serious egg quality problems. In models developed using artificial neural networks (ANNs) and supervised machine learning, collective changes in the expression of a limited suite of genes (233) representing <2% of the queried ovary transcriptome explained >90% of the eventual variance in embryo survival. Egg quality related to minor changes in gene expression (<0.2-fold), with most individual transcripts making a small contribution (<1%) to the overall prediction of egg quality. These findings indicate that the predictive power of the transcriptome as regards egg quality resides not in levels of individual genes, but rather in the collective, coordinated expression of a suite of transcripts constituting a transcriptomic "fingerprint". Correlation analyses of the corresponding candidate genes indicated that dysfunction of the ubiquitin-26S proteasome, COP9 signalosome, and subsequent control of the cell cycle engenders embryonic developmental incompetence. The affected gene networks are centrally involved in regulation of early development in all vertebrates, including humans. By assessing collective levels of the relevant ovarian transcripts via ANNs we were able, for the first time in any vertebrate, to accurately predict the subsequent embryo developmental potential of eggs from individual females. Our results show that the transcriptomic fingerprint evidencing developmental dysfunction is highly predictive of, and therefore likely to regulate, egg quality, a biologically complex trait crucial to reproductive fitness.

Bipteria vetusta n. sp. – an old parasite in an old host: tracing the origin of myxosporean parasitism in vertebrates.

PubMed

Kodádková, Alena; Bartošová-Sojková, Pavla; Holzer, Astrid S; Fiala, Ivan

2015-03-01

Myxosporea (Myxozoa), a group of parasitic Cnidaria, use mostly bony fishes (Teleostei) as intermediate hosts; however, they can also parasitize other vertebrates such as cartilaginous fish (Chondrichthyes). Molecular data of myxosporeans from sharks and rays (Elasmobranchii) revealed these parasites to be one of the most basal representatives in the myxosporean phylogenetic tree, suggesting their ancient evolutionary history. A new myxosporean species, Bipteria vetusta n. sp., was found in the gall bladder of rabbit fish, Chimaera monstrosa (Holocephali; Chondrichthyes), and ssrDNA-based phylogeny revealed its basal position within the marine myxosporean lineage. Molecular dating based on ssrDNA analysis suggested the origin of a stem lineage leading to the marine myxosporean lineage at the time of the origin of Chondrichthyes in the Silurian era. The two common lineages of Myxozoa, Myxosporea and Malacosporea, were estimated to have split from their common ancestor in the Cambrian era. Tracing the history of evolution of the "vertebrate host type" character in the context of molecular dating showed that cartilaginous fish represented an ancestral state for all myxosporeans. Teleosts were very likely subsequently parasitized by myxozoans four times, independently. Myxosporean radiation and diversification appear to correlate with intermediate host evolution. The first intermediate hosts of myxosporeans were cartilaginous fish. When bony fish evolved and radiated, myxosporeans switched and adapted to bony fish, and subsequently greatly diversified in this new host niche. We believe that the present study is the first attempt at molecular dating of myxozoan evolution based on an old myxosporean species – a living myxosporean fossil. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Ovary Transcriptome Profiling via Artificial Intelligence Reveals a Transcriptomic Fingerprint Predicting Egg Quality in Striped Bass, Morone saxatilis

PubMed Central

2014-01-01

Inherited gene transcripts deposited in oocytes direct early embryonic development in all vertebrates, but transcript profiles indicative of embryo developmental competence have not previously been identified. We employed artificial intelligence to model profiles of maternal ovary gene expression and their relationship to egg quality, evaluated as production of viable mid-blastula stage embryos, in the striped bass (Morone saxatilis), a farmed species with serious egg quality problems. In models developed using artificial neural networks (ANNs) and supervised machine learning, collective changes in the expression of a limited suite of genes (233) representing <2% of the queried ovary transcriptome explained >90% of the eventual variance in embryo survival. Egg quality related to minor changes in gene expression (<0.2-fold), with most individual transcripts making a small contribution (<1%) to the overall prediction of egg quality. These findings indicate that the predictive power of the transcriptome as regards egg quality resides not in levels of individual genes, but rather in the collective, coordinated expression of a suite of transcripts constituting a transcriptomic “fingerprint”. Correlation analyses of the corresponding candidate genes indicated that dysfunction of the ubiquitin-26S proteasome, COP9 signalosome, and subsequent control of the cell cycle engenders embryonic developmental incompetence. The affected gene networks are centrally involved in regulation of early development in all vertebrates, including humans. By assessing collective levels of the relevant ovarian transcripts via ANNs we were able, for the first time in any vertebrate, to accurately predict the subsequent embryo developmental potential of eggs from individual females. Our results show that the transcriptomic fingerprint evidencing developmental dysfunction is highly predictive of, and therefore likely to regulate, egg quality, a biologically complex trait crucial to reproductive fitness. PMID:24820964

An Ancient Gene Network Is Co-opted for Teeth on Old and New Jaws

PubMed Central

Fraser, Gareth J; Hulsey, C. Darrin; Bloomquist, Ryan F; Uyesugi, Kristine; Manley, Nancy R; Streelman, J. Todd

2009-01-01

Vertebrate dentitions originated in the posterior pharynx of jawless fishes more than half a billion years ago. As gnathostomes (jawed vertebrates) evolved, teeth developed on oral jaws and helped to establish the dominance of this lineage on land and in the sea. The advent of oral jaws was facilitated, in part, by absence of hox gene expression in the first, most anterior, pharyngeal arch. Much later in evolutionary time, teleost fishes evolved a novel toothed jaw in the pharynx, the location of the first vertebrate teeth. To examine the evolutionary modularity of dentitions, we asked whether oral and pharyngeal teeth develop using common or independent gene regulatory pathways. First, we showed that tooth number is correlated on oral and pharyngeal jaws across species of cichlid fishes from Lake Malawi (East Africa), suggestive of common regulatory mechanisms for tooth initiation. Surprisingly, we found that cichlid pharyngeal dentitions develop in a region of dense hox gene expression. Thus, regulation of tooth number is conserved, despite distinct developmental environments of oral and pharyngeal jaws; pharyngeal jaws occupy hox-positive, endodermal sites, and oral jaws develop in hox-negative regions with ectodermal cell contributions. Next, we studied the expression of a dental gene network for tooth initiation, most genes of which are similarly deployed across the two disparate jaw sites. This collection of genes includes members of the ectodysplasin pathway, eda and edar, expressed identically during the patterning of oral and pharyngeal teeth. Taken together, these data suggest that pharyngeal teeth of jawless vertebrates utilized an ancient gene network before the origin of oral jaws, oral teeth, and ectodermal appendages. The first vertebrate dentition likely appeared in a hox-positive, endodermal environment and expressed a genetic program including ectodysplasin pathway genes. This ancient regulatory circuit was co-opted and modified for teeth in oral jaws of the first jawed vertebrate, and subsequently deployed as jaws enveloped teeth on novel pharyngeal jaws. Our data highlight an amazing modularity of jaws and teeth as they coevolved during the history of vertebrates. We exploit this diversity to infer a core dental gene network, common to the first tooth and all of its descendants. PMID:19215146

Mid-Holocene vertebrate bone Concentration-Lagerstätte on oceanic island Mauritius provides a window into the ecosystem of the dodo ( Raphus cucullatus)

NASA Astrophysics Data System (ADS)

Rijsdijk, Kenneth F.; Hume, Julian P.; Bunnik, Frans; Florens, F. B. Vincent; Baider, Claudia; Shapiro, Beth; van der Plicht, Johannes; Janoo, Anwar; Griffiths, Owen; van den Hoek Ostende, Lars W.; Cremer, Holger; Vernimmen, Tamara; De Louw, Perry G. B.; Bholah, Assenjee; Saumtally, Salem; Porch, Nicolas; Haile, James; Buckley, Mike; Collins, Matthew; Gittenberger, Edmund

2009-01-01

Although the recent history of human colonisation and impact on Mauritius is well documented, virtually no records of the pre-human native ecosystem exist, making it difficult to assess the magnitude of the changes brought about by human settlement. Here, we describe a 4000-year-old fossil bed at Mare aux Songes (MAS) in south-eastern Mauritius that contains both macrofossils (vertebrate fauna, gastropods, insects and flora) and microfossils (diatoms, pollen, spores and phytoliths). With >250 bone fragments/m 2 and comprising 50% of all known extinct and extant vertebrate species ( ns = 44) of Mauritius, MAS may constitute the first Holocene vertebrate bone Concentration-Lagerstätte identified on an oceanic volcanic island. Fossil remains are dominated by extinct giant tortoises Cylindraspis spp. (63%), passerines (˜10%), small bats (7.8%) and dodo Raphus cucullatus (7.1%). Twelve radiocarbon ages [four of them duplicates] from bones and other material suggest that accumulation of fossils took place within several centuries. An exceptional combination of abiotic conditions led to preservation of bones, bone collagen, plant tissue and microfossils. Although bone collagen is well preserved, DNA from dodo and other Mauritian vertebrates has proved difficult. Our analysis suggests that from ca 4000 years ago (4 ka), rising sea levels created a freshwater lake at MAS, generating an oasis in an otherwise dry environment which attracted a diverse vertebrate fauna. Subsequent aridification in the south-west Indian Ocean region may have increased carcass accumulation during droughts, contributing to the exceptionally high fossil concentration. The abundance of floral and faunal remains in this Lagerstätte offers a unique opportunity to reconstruct a pre-human ecosystem on an oceanic island, providing a key foundation for assessing the vulnerability of island ecosystems to human impact.

Origin and Evolution of Retinoid Isomerization Machinery in Vertebrate Visual Cycle: Hint from Jawless Vertebrates

PubMed Central

Stearn, Olivia; Li, Yan; Campos, Maria Mercedes; Gentleman, Susan; Rogozin, Igor B.; Redmond, T. Michael

2012-01-01

In order to maintain visual sensitivity at all light levels, the vertebrate eye possesses a mechanism to regenerate the visual pigment chromophore 11-cis retinal in the dark enzymatically, unlike in all other taxa, which rely on photoisomerization. This mechanism is termed the visual cycle and is localized to the retinal pigment epithelium (RPE), a support layer of the neural retina. Speculation has long revolved around whether more primitive chordates, such as tunicates and cephalochordates, anticipated this feature. The two key enzymes of the visual cycle are RPE65, the visual cycle all-trans retinyl ester isomerohydrolase, and lecithin:retinol acyltransferase (LRAT), which generates RPE65’s substrate. We hypothesized that the origin of the vertebrate visual cycle is directly connected to an ancestral carotenoid oxygenase acquiring a new retinyl ester isomerohydrolase function. Our phylogenetic analyses of the RPE65/BCMO and N1pC/P60 (LRAT) superfamilies show that neither RPE65 nor LRAT orthologs occur in tunicates (Ciona) or cephalochordates (Branchiostoma), but occur in Petromyzon marinus (Sea Lamprey), a jawless vertebrate. The closest homologs to RPE65 in Ciona and Branchiostoma lacked predicted functionally diverged residues found in all authentic RPE65s, but lamprey RPE65 contained all of them. We cloned RPE65 and LRATb cDNAs from lamprey RPE and demonstrated appropriate enzymatic activities. We show that Ciona ß-carotene monooxygenase a (BCMOa) (previously annotated as an RPE65) has carotenoid oxygenase cleavage activity but not RPE65 activity. We verified the presence of RPE65 in lamprey RPE by immunofluorescence microscopy, immunoblot and mass spectrometry. On the basis of these data we conclude that the crucial transition from the typical carotenoid double bond cleavage functionality (BCMO) to the isomerohydrolase functionality (RPE65), coupled with the origin of LRAT, occurred subsequent to divergence of the more primitive chordates (tunicates, etc.) in the last common ancestor of the jawless and jawed vertebrates. PMID:23209628

Teleost Fish-Specific Preferential Retention of Pigmentation Gene-Containing Families After Whole Genome Duplications in Vertebrates

PubMed Central

Lorin, Thibault; Brunet, Frédéric G.; Laudet, Vincent; Volff, Jean-Nicolas

2018-01-01

Vertebrate pigmentation is a highly diverse trait mainly determined by neural crest cell derivatives. It has been suggested that two rounds (1R/2R) of whole-genome duplications (WGDs) at the basis of vertebrates allowed changes in gene regulation associated with neural crest evolution. Subsequently, the teleost fish lineage experienced other WGDs, including the teleost-specific Ts3R before teleost radiation and the more recent Ss4R at the basis of salmonids. As the teleost lineage harbors the highest number of pigment cell types and pigmentation diversity in vertebrates, WGDs might have contributed to the evolution and diversification of the pigmentation gene repertoire in teleosts. We have compared the impact of the basal vertebrate 1R/2R duplications with that of the teleost-specific Ts3R and salmonid-specific Ss4R WGDs on 181 gene families containing genes involved in pigmentation. We show that pigmentation genes (PGs) have been globally more frequently retained as duplicates than other genes after Ts3R and Ss4R but not after the early 1R/2R. This is also true for non-pigmentary paralogs of PGs, suggesting that the function in pigmentation is not the sole key driver of gene retention after WGDs. On the long-term, specific categories of PGs have been repeatedly preferentially retained after ancient 1R/2R and Ts3R WGDs, possibly linked to the molecular nature of their proteins (e.g., DNA binding transcriptional regulators) and their central position in protein-protein interaction networks. Taken together, our results support a major role of WGDs in the diversification of the pigmentation gene repertoire in the teleost lineage, with a possible link with the diversity of pigment cell lineages observed in these animals compared to other vertebrates. PMID:29599177

Origin and evolution of retinoid isomerization machinery in vertebrate visual cycle: hint from jawless vertebrates.

PubMed

Poliakov, Eugenia; Gubin, Alexander N; Stearn, Olivia; Li, Yan; Campos, Maria Mercedes; Gentleman, Susan; Rogozin, Igor B; Redmond, T Michael

2012-01-01

In order to maintain visual sensitivity at all light levels, the vertebrate eye possesses a mechanism to regenerate the visual pigment chromophore 11-cis retinal in the dark enzymatically, unlike in all other taxa, which rely on photoisomerization. This mechanism is termed the visual cycle and is localized to the retinal pigment epithelium (RPE), a support layer of the neural retina. Speculation has long revolved around whether more primitive chordates, such as tunicates and cephalochordates, anticipated this feature. The two key enzymes of the visual cycle are RPE65, the visual cycle all-trans retinyl ester isomerohydrolase, and lecithin:retinol acyltransferase (LRAT), which generates RPE65's substrate. We hypothesized that the origin of the vertebrate visual cycle is directly connected to an ancestral carotenoid oxygenase acquiring a new retinyl ester isomerohydrolase function. Our phylogenetic analyses of the RPE65/BCMO and N1pC/P60 (LRAT) superfamilies show that neither RPE65 nor LRAT orthologs occur in tunicates (Ciona) or cephalochordates (Branchiostoma), but occur in Petromyzon marinus (Sea Lamprey), a jawless vertebrate. The closest homologs to RPE65 in Ciona and Branchiostoma lacked predicted functionally diverged residues found in all authentic RPE65s, but lamprey RPE65 contained all of them. We cloned RPE65 and LRATb cDNAs from lamprey RPE and demonstrated appropriate enzymatic activities. We show that Ciona ß-carotene monooxygenase a (BCMOa) (previously annotated as an RPE65) has carotenoid oxygenase cleavage activity but not RPE65 activity. We verified the presence of RPE65 in lamprey RPE by immunofluorescence microscopy, immunoblot and mass spectrometry. On the basis of these data we conclude that the crucial transition from the typical carotenoid double bond cleavage functionality (BCMO) to the isomerohydrolase functionality (RPE65), coupled with the origin of LRAT, occurred subsequent to divergence of the more primitive chordates (tunicates, etc.) in the last common ancestor of the jawless and jawed vertebrates.

An intramedullary capillary hemangioma of the spine with an underlying plasmocytoma.

PubMed

Melcher, Carolin; Wegener, Bernd; Niederhagen, Manuel; Jansson, Volkmar; Birkenmaier, Christof

2013-07-01

In contrast to vertebral hemangiomas, which are very common within the general population, only 3% to 5% of patients with plasma cell dyscrasia show a single osteolytic bone lesion due to plasma cell infiltration without the evidence of generalized myeloma. The vast majority of these hemangiomas are completely asymptomatic and only discovered incidentally. In rare occasions, representing only 1% to 2% of the known lesions, a locally aggressive subtype can cause problems analogous to the ones triggered by a plasmocytoma, ranging from back pain to vertebral compression fractures to neurologic deficit, resulting from nerve root or spinal cord compression. Both entities are extensively discussed in the literature, but finding both lesions in one is rare if not described for the first time. To advise colleagues that the differential diagnosis between benign and malignant vertebral tumors can be harder than expected and has to be definitely made to avoid severe consequences for the patient. A 46-year-old healthy man presented to the emergency department with an acute onset of thoracic back pain after a trivial incident. Although his medical history included no known diseases and no history of back pain, plain X-rays raised the clear suspicion of a fracture of T6 that was verified in computed tomography scans. Visual analog scale; neurologic status; tumor recurrence. The case of the patient was evaluated retrospectively according to standard procedures, clinical outcome, and in review of the literature. Because there is still controversy about the best treatment (local radiation vs. operation vs. combination) of a solitary skeletal plasmocytoma, no gold standard has been established until now. Especially if a patient needs an emergency operation before all test results are obtained, each surgeon has to decide individually. Capillary hemangiomas can hide underlying plasmocytomas, which might demand totally different treatment strategies. Although our patient did not match the common criteria for a solitary plasmocytoma, one has to discuss whether a stand-alone decompression and biopsy would have been the emergency treatment of choice. Such a strategy would have reduced the risk of tumor spreading and would have made radiotherapy easier, whereas on the other hand requiring a secondary stabilization procedure later on. Copyright © 2013 Elsevier Inc. All rights reserved.

Prevalence and Cost of Subsequent Fractures Among U.S. Patients with an Incident Fracture.

PubMed

Weaver, Jessica; Sajjan, Shiva; Lewiecki, E Michael; Harris, Steven T; Marvos, Panagiotis

2017-04-01

The prevalence and cost of subsequent fractures among patients with an incident fracture are not well defined. To assess the prevalence of, and costs associated with, subsequent fractures in the year after an incident fracture. This was a retrospective claims database analysis using data from Humana Medicare Advantage claims (Medicare group) and Optum Insight Clinformatics Data Mart commercial claims (commercial group). Patients included in the study had a claim for a qualifying fracture occurring between January 2008 and December 2013 (index fracture), were continuously enrolled in the health plan for ≥ 1 year before and after the index fracture, and were aged ≥ 65 years in the Medicare group or ≥ 50 years in the commercial group at the time of the index fracture. Subsequent fractures were identified by ICD-9-CM codes and were defined as the second fracture occurring ≥ 3 to ≤ 12 months after the index fracture (≥ 6 to ≤ 12 months for fractures at the same site as the index fracture). Rates of subsequent fractures were calculated as the number of patients who had a subsequent fracture divided by the total sample size. After propensity matching of demographic and clinical variables, we determined the total medical and pharmacy costs accrued within 1 year of the index fracture by patients with and without a subsequent fracture. Health care costs were compared between patients with and without a subsequent fracture using McNemar's test. A total of 45,603 patients were included in the Medicare group, and 54,145 patients were included in the commercial group. In the Medicare group, 7,604 (16.7%) patients experienced a subsequent fracture. The proportion of patients with a subsequent fracture was highest among patients with multiple index fractures (26.2%, n = 905), followed by those with hip (25.5%, n = 1,280) and vertebral (20.2%, n = 1,908) index fractures. In the commercial group, 6,256 (11.6%) patients experienced a subsequent fracture. The proportion of patients with a subsequent fracture paralleled those observed in the Medicare group: 24.5% (n = 808) in patients with multiple index fractures, 22.0% (n = 525) in those with hip fracture, and 14.5% (n = 841) in those with vertebral fracture. For vertebral, hip, and nonhip nonvertebral fractures, subsequent fractures were most frequently of the same type as the index fracture. The mean total health care cost (sum of medical and pharmacy costs) in the year following the incident fracture for the Medicare group was $27,844 and differed significantly between patients with and without a subsequent fracture ($34,897 vs. $20,790; P < 0.001). The mean total health care cost in the year following the incident fracture for the commercial group was $29,316 and also differed significantly between patients with and without a subsequent fracture ($39,501 vs. $19,131; P < 0.001). Among patients with an incident fracture, those who experienced a subsequent fracture in the following year had significantly higher health care costs than those who did not. A subsequent fracture is most likely to be of the same type as the initial fracture. This study was funded by Merck & Co. Other than through the employer relationships disclosed here, Merck & Co did not have a role in the study design, data collection, interpretation of the data, in writing of the manuscript, or in the decision to submit the manuscript for publication. Weaver and Marvos are employees of Merck & Co. Sajjan was an employee of Merck & Co. and owned stock in the company at the time of the study. Lewiecki has received consulting and/or speaker honoraria from Merck, AbbVie, AgNovos Healthcare, Alexion Pharmaceuticals, Amgen, Eli Lilly and Company, Radius Health, Shire, and TheraNova. Lewiecki has received research grant support from Merck, Amgen, and Eli Lilly and Company and serves as a board member for the National Osteoporosis Foundation, the International Society for Clinical Densitometry, and the Osteoporosis Foundation of New Mexico. Harris has received consulting honoraria from Merck, Alexion Pharmaceuticals, Amgen, Eli Lilly and Company, Gilead Sciences, Primus Pharmaceuticals, and Radius Health. Study concept and design were contributed by Weave and Sajjan. Lewiecki collected the data, and data interpretation was performed by all the authors. The manuscript was written and revised by Weaver, Lewiecki, and Harris.

Establishment of Hox vertebral identities in the embryonic spine precursors

PubMed Central

Iimura, Tadahiro; Denans, Nicolas; Pourquié, Olivier

2012-01-01

Summary The vertebrate spine exhibits two striking characteristics. The first one is the periodic arrangement of its elements – the vertebrae – along the antero-posterior axis. This segmented organization is the result of somitogenesis, which takes place during organogenesis. The segmentation machinery involves a molecular oscillator – the segmentation clock – which delivers a periodic signal controlling somite production. During embryonic axis elongation, this signal is displaced posteriorly by a system of traveling signaling gradients – the wavefront – which depends on the Wnt, FGF and retinoic acid pathways. The other characteristic feature of the spine is the subdivision of groups of vertebrae into anatomical domains, such as the cervical, thoracic, lumbar, sacral and caudal regions. This axial regionalization is controlled by a set of transcription factors called Hox genes. Hox genes exhibit nested expression domains in the somites which reflect their linear arrangement along the chromosomes– a property termed colinearity. The colinear disposition of Hox genes expression domains provides a blueprint for the regionalization of the future vertebral territories of the spine. In amniotes, Hox genes are activated in the somite precursors of the epiblast in a temporal colinear sequence and they were proposed to control their progressive ingression into the nascent paraxial mesoderm. Consequently, the positioning of the expression domains of Hox genes along the antero-posterior axis is largely controlled by the timing of Hox activation during gastrulation. Positioning of the somitic Hox domains is subsequently refined through a cross talk with the segmentation machinery in the presomitic mesoderm. In this review, we focus on our current understanding of the embryonic mechanisms that establish vertebral identities during vertebrate development. PMID:19651306

Compact storage of medical images with patient information.

PubMed

Acharya, R; Anand, D; Bhat, S; Niranjan, U C

2001-12-01

Digital watermarking is a technique of hiding specific identification data for copyright authentication. This technique is adapted here for interleaving patient information with medical images to reduce storage and transmission overheads. The text data are encrypted before interleaving with images to ensure greater security. The graphical signals are compressed and subsequently interleaved with the image. Differential pulse-code-modulation and adaptive-delta-modulation techniques are employed for data compression, and encryption and results are tabulated for a specific example.

Compression Strength of Sulfur Concrete Subjected to Extreme Cold

NASA Technical Reports Server (NTRS)

Grugel, Richard N.

2008-01-01

Sulfur concrete cubes were cycled between liquid nitrogen and room temperature to simulate extreme exposure conditions. Subsequent compression testing showed the strength of cycled samples to be roughly five times less than those non-cycled. Fracture surface examination showed de-bonding of the sulfur from the aggregate material in the cycled samples but not in those non-cycled. The large discrepancy found, between the samples is attributed to the relative thermal properties of the materials constituting the concrete.

Pre-loading of components during laser peenforming

DOEpatents

Hackel, Lloyd A [Livermore, CA; Halpin, John M [Tracy, CA; Harris, Fritz B [Rocklin, CA

2003-12-30

A method and apparatus are provided for forming shapes and contours in metal sections by prestressing a workpiece and generating laser induced compressive stress on the surface of the metal workpiece. The step of prestressing the workpiece is carried out with a jig. The laser process can generate deep compressive stresses to shape even thick components without inducing unwanted tensile stress at the metal surface. The precision of the laser-induced stress enables exact prediction and subsequent contouring of parts.

Vertebral body or intervertebral disc wedging: which contributes more to thoracolumbar kyphosis in ankylosing spondylitis patients?: A retrospective study.

PubMed

Liu, Hao; Qian, Bang-Ping; Qiu, Yong; Wang, Yan; Wang, Bin; Yu, Yang; Zhu, Ze-Zhang

2016-09-01

Both vertebral body wedging and disc wedging are found in ankylosing spondylitis (AS) patients with thoracolumbar kyphosis. However, their relative contribution to thoracolumbar kyphosis is not fully understood. The objective of this study was to compare different contributions of vertebral and disc wedging to the thoracolumbar kyphosis in AS patients, and to analyze the relationship between the apical vertebral wedging angle and thoracolumbar kyphosis.From October 2009 to October 2013, a total of 59 consecutive AS patients with thoracolumbar kyphosis with a mean age of 38.1 years were recruited in this study. Based on global kyphosis (GK), 26 patients with GK < 70° were assigned to group A, and the other 33 patients with GK ≥ 70° were included in group B. Each GK was divided into disc wedge angles and vertebral wedge angles. The wedging angle of each disc and vertebra comprising the thoracolumbar kyphosis was measured, and the proportion of the wedging angle to the GK was calculated accordingly. Intergroup and intragroup comparisons were subsequently performed to investigate the different contributions of disc and vertebra to the GK. The correlation between the apical vertebral wedging angle and GK was calculated by Pearson correlation analysis. The duration of disease and sex were also recorded in this study.With respect to the mean disease duration, significant difference was observed between the two groups (P < 0.01). The wedging angle and wedging percentage of discs were significantly higher than those of vertebrae in group A (34.8° ± 2.5° vs 26.7° ± 2.7°, P < 0.01 and 56.6% vs 43.4%, P < 0.01), whereas disc wedging and disc wedging percentage were significantly lower than vertebrae in group B (37.6° ± 7.0° vs 50.1° ± 5.1°, P < 0.01 and 42.7% vs 57.3%, P < 0.01). The wedging of vertebrae was significantly higher in group B than in group A (50.1° ± 5.1° vs 26.7° ± 2.7°, P < 0.01). Additionally, correlation analysis revealed a significant correlation between the apical vertebral wedging angle and GK (R = 0.850, P = 0.001).Various disc and vertebral wedging exist in thoracolumbar kyphosis secondary to AS. The discs wedging contributes more to the thoracolumbar kyphosis in patients with GK < 70° than vertebral wedging, whereas vertebral wedging is more conducive to the thoracolumbar kyphosis in patients with GK ≥ 70°, indicating different biomechanical pathogenesis in varied severity of thoracolumbar kyphosis secondary to AS.

Vertebral body or intervertebral disc wedging: which contributes more to thoracolumbar kyphosis in ankylosing spondylitis patients?

PubMed Central

Liu, Hao; Qian, Bang-Ping; Qiu, Yong; Wang, Yan; Wang, Bin; Yu, Yang; Zhu, Ze-Zhang

2016-01-01

Abstract Both vertebral body wedging and disc wedging are found in ankylosing spondylitis (AS) patients with thoracolumbar kyphosis. However, their relative contribution to thoracolumbar kyphosis is not fully understood. The objective of this study was to compare different contributions of vertebral and disc wedging to the thoracolumbar kyphosis in AS patients, and to analyze the relationship between the apical vertebral wedging angle and thoracolumbar kyphosis. From October 2009 to October 2013, a total of 59 consecutive AS patients with thoracolumbar kyphosis with a mean age of 38.1 years were recruited in this study. Based on global kyphosis (GK), 26 patients with GK < 70° were assigned to group A, and the other 33 patients with GK ≥ 70° were included in group B. Each GK was divided into disc wedge angles and vertebral wedge angles. The wedging angle of each disc and vertebra comprising the thoracolumbar kyphosis was measured, and the proportion of the wedging angle to the GK was calculated accordingly. Intergroup and intragroup comparisons were subsequently performed to investigate the different contributions of disc and vertebra to the GK. The correlation between the apical vertebral wedging angle and GK was calculated by Pearson correlation analysis. The duration of disease and sex were also recorded in this study. With respect to the mean disease duration, significant difference was observed between the two groups (P < 0.01). The wedging angle and wedging percentage of discs were significantly higher than those of vertebrae in group A (34.8° ± 2.5° vs 26.7° ± 2.7°, P < 0.01 and 56.6% vs 43.4%, P < 0.01), whereas disc wedging and disc wedging percentage were significantly lower than vertebrae in group B (37.6° ± 7.0° vs 50.1° ± 5.1°, P < 0.01 and 42.7% vs 57.3%, P < 0.01). The wedging of vertebrae was significantly higher in group B than in group A (50.1° ± 5.1° vs 26.7° ± 2.7°, P < 0.01). Additionally, correlation analysis revealed a significant correlation between the apical vertebral wedging angle and GK (R = 0.850, P = 0.001). Various disc and vertebral wedging exist in thoracolumbar kyphosis secondary to AS. The discs wedging contributes more to the thoracolumbar kyphosis in patients with GK < 70° than vertebral wedging, whereas vertebral wedging is more conducive to the thoracolumbar kyphosis in patients with GK ≥ 70°, indicating different biomechanical pathogenesis in varied severity of thoracolumbar kyphosis secondary to AS. PMID:27661026

Power supply

DOEpatents

Hart, Edward J.; Leeman, James E.; MacDougall, Hugh R.; Marron, John J.; Smith, Calvin C.

1976-01-01

An electric power supply employs a striking means to initiate ferroelectric elements which provide electrical energy output which subsequently initiates an explosive charge which initiates a second ferroelectric current generator to deliver current to the coil of a magnetic field current generator, creating a magnetic field around the coil. Continued detonation effects compression of the magnetic field and subsequent generation and delivery of a large output current to appropriate output loads.

Iterative dictionary construction for compression of large DNA data sets.

PubMed

Kuruppu, Shanika; Beresford-Smith, Bryan; Conway, Thomas; Zobel, Justin

2012-01-01

Genomic repositories increasingly include individual as well as reference sequences, which tend to share long identical and near-identical strings of nucleotides. However, the sequential processing used by most compression algorithms, and the volumes of data involved, mean that these long-range repetitions are not detected. An order-insensitive, disk-based dictionary construction method can detect this repeated content and use it to compress collections of sequences. We explore a dictionary construction method that improves repeat identification in large DNA data sets. Our adaptation, COMRAD, of an existing disk-based method identifies exact repeated content in collections of sequences with similarities within and across the set of input sequences. COMRAD compresses the data over multiple passes, which is an expensive process, but allows COMRAD to compress large data sets within reasonable time and space. COMRAD allows for random access to individual sequences and subsequences without decompressing the whole data set. COMRAD has no competitor in terms of the size of data sets that it can compress (extending to many hundreds of gigabytes) and, even for smaller data sets, the results are competitive compared to alternatives; as an example, 39 S. cerevisiae genomes compressed to 0.25 bits per base.

Recrystallization characteristics and interfacial oxides on the compression bonding interface

NASA Astrophysics Data System (ADS)

Xie, Bijun; Sun, Mingyue; Xu, Bin; Li, Dianzhong

2018-05-01

Up to now, the mechanism of interface bonding is still not fully understood. This work presents interfacial characteristics of 316LN stainless steel bonding joint after cold compression bonding with subsequent annealing. EBSD analysis shows that fine recrystallization grains preferentially appear near the bonding interface and grow towards both sides of the interface. Transmission electron microscopy reveals that initial cold compression bonding disintegrates the native oxide scales and brings pristine metal from both sides of the interface come into intimate contact, while the broken oxide particles are remained at the original interface. The results indicate that partial bonding can be achieved by cold compression bonding with post-annealing treatment and recrystallization firstly occurs along the bonding interface. However, the interfacial oxides impede the recrystallization grains step over the interface and hinder the complete healing of the bonding interface.

Bunch compression efficiency of the femtosecond electron source at Chiang Mai University

NASA Astrophysics Data System (ADS)

Thongbai, C.; Kusoljariyakul, K.; Saisut, J.

2011-07-01

A femtosecond electron source has been developed at the Plasma and Beam Physics Research Facility (PBP), Chiang Mai University (CMU), Thailand. Ultra-short electron bunches can be produced with a bunch compression system consisting of a thermionic cathode RF-gun, an alpha-magnet as a magnetic bunch compressor, and a linear accelerator as a post acceleration section. To obtain effective bunch compression, it is crucial to provide a proper longitudinal phase-space distribution at the gun exit matched to the subsequent beam transport system. Via beam dynamics calculations and experiments, we investigate the bunch compression efficiency for various RF-gun fields. The particle distribution at the RF-gun exit will be tracked numerically through the alpha-magnet and beam transport. Details of the study and results leading to an optimum condition for our system will be presented.

A Discriminative Sentence Compression Method as Combinatorial Optimization Problem

NASA Astrophysics Data System (ADS)

Hirao, Tsutomu; Suzuki, Jun; Isozaki, Hideki

In the study of automatic summarization, the main research topic was `important sentence extraction' but nowadays `sentence compression' is a hot research topic. Conventional sentence compression methods usually transform a given sentence into a parse tree or a dependency tree, and modify them to get a shorter sentence. However, this method is sometimes too rigid. In this paper, we regard sentence compression as an combinatorial optimization problem that extracts an optimal subsequence of words. Hori et al. also proposed a similar method, but they used only a small number of features and their weights were tuned by hand. We introduce a large number of features such as part-of-speech bigrams and word position in the sentence. Furthermore, we train the system by discriminative learning. According to our experiments, our method obtained better score than other methods with statistical significance.

Detecting double compressed MPEG videos with the same quantization matrix and synchronized group of pictures structure

NASA Astrophysics Data System (ADS)

Aghamaleki, Javad Abbasi; Behrad, Alireza

2018-01-01

Double compression detection is a crucial stage in digital image and video forensics. However, the detection of double compressed videos is challenging when the video forger uses the same quantization matrix and synchronized group of pictures (GOP) structure during the recompression history to conceal tampering effects. A passive approach is proposed for detecting double compressed MPEG videos with the same quantization matrix and synchronized GOP structure. To devise the proposed algorithm, the effects of recompression on P frames are mathematically studied. Then, based on the obtained guidelines, a feature vector is proposed to detect double compressed frames on the GOP level. Subsequently, sparse representations of the feature vectors are used for dimensionality reduction and enrich the traces of recompression. Finally, a support vector machine classifier is employed to detect and localize double compression in temporal domain. The experimental results show that the proposed algorithm achieves the accuracy of more than 95%. In addition, the comparisons of the results of the proposed method with those of other methods reveal the efficiency of the proposed algorithm.

Compression-induced texture change in NiMnGa-polymer composites observed by synchrotron radiation

NASA Astrophysics Data System (ADS)

Scheerbaum, Nils; Hinz, Dietrich; Gutfleisch, Oliver; Skrotzki, Werner; Schultz, Ludwig

2007-05-01

Composites consisting of magnetic shape memory (MSM) particles embedded in a polyester matrix were prepared. Single-crystalline MSM particles were obtained by mortar grinding of melt-extracted and subsequently annealed Ni50.9Mn27.1Ga22.0 (at. %) fibers. The crystal structure of the martensite is tetragonal (5M) with c

Wave energy devices with compressible volumes.

PubMed

Kurniawan, Adi; Greaves, Deborah; Chaplin, John

2014-12-08

We present an analysis of wave energy devices with air-filled compressible submerged volumes, where variability of volume is achieved by means of a horizontal surface free to move up and down relative to the body. An analysis of bodies without power take-off (PTO) systems is first presented to demonstrate the positive effects a compressible volume could have on the body response. Subsequently, two compressible device variations are analysed. In the first variation, the compressible volume is connected to a fixed volume via an air turbine for PTO. In the second variation, a water column separates the compressible volume from another volume, which is fitted with an air turbine open to the atmosphere. Both floating and bottom-fixed, axisymmetric, configurations are considered, and linear analysis is employed throughout. Advantages and disadvantages of each device are examined in detail. Some configurations with displaced volumes less than 2000 m 3 and with constant turbine coefficients are shown to be capable of achieving 80% of the theoretical maximum absorbed power over a wave period range of about 4 s.

Wave energy devices with compressible volumes

PubMed Central

Kurniawan, Adi; Greaves, Deborah; Chaplin, John

2014-01-01

We present an analysis of wave energy devices with air-filled compressible submerged volumes, where variability of volume is achieved by means of a horizontal surface free to move up and down relative to the body. An analysis of bodies without power take-off (PTO) systems is first presented to demonstrate the positive effects a compressible volume could have on the body response. Subsequently, two compressible device variations are analysed. In the first variation, the compressible volume is connected to a fixed volume via an air turbine for PTO. In the second variation, a water column separates the compressible volume from another volume, which is fitted with an air turbine open to the atmosphere. Both floating and bottom-fixed, axisymmetric, configurations are considered, and linear analysis is employed throughout. Advantages and disadvantages of each device are examined in detail. Some configurations with displaced volumes less than 2000 m3 and with constant turbine coefficients are shown to be capable of achieving 80% of the theoretical maximum absorbed power over a wave period range of about 4 s. PMID:25484609

Lower vertebrate and invertebrate models of Alzheimer's disease - A review.

PubMed

Sharma, Neha; Khurana, Navneet; Muthuraman, Arunachalam

2017-11-15

Alzheimer's disease is a common neurodegenerative disorder which is characterized by the presence of beta- amyloid protein and neurofibrillary tangles (NFTs) in the brain. Till now, various higher vertebrate models have been in use to study the pathophysiology of this disease. But, these models possess some limitations like ethical restrictions, high cost, difficult maintenance of large quantity and lesser reproducibility. Besides, various lower chordate animals like Danio rerio, Drosophila melanogaster, Caenorhabditis elegans and Ciona intestinalis have been proved to be an important model for the in vivo determination of targets of drugs with least limitations. In this article, we reviewed different studies conducted on theses models for the better understanding of the pathophysiology of AD and their subsequent application as a potential tool in the preclinical evaluation of new drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

Health economic aspects of vertebral augmentation procedures.

PubMed

Borgström, F; Beall, D P; Berven, S; Boonen, S; Christie, S; Kallmes, D F; Kanis, J A; Olafsson, G; Singer, A J; Åkesson, K

2015-04-01

We reviewed all peer-reviewed papers analysing the cost-effectiveness of vertebroplasty and balloon kyphoplasty for osteoporotic vertebral compression fractures. In general, the procedures appear to be cost effective but are very dependent upon model input details. Better data, rather than new models, are needed to answer outstanding questions. Vertebral augmentation procedures (VAPs), including vertebroplasty (VP) and balloon kyphoplasty (BKP), seek to stabilise fractured vertebral bodies and reduce pain. The aim of this paper is to review current literature on the cost-effectiveness of VAPs as well as to discuss the challenges for economic evaluation in this research area. A systematic literature search was conducted to identify existing published studies on the cost-effectiveness of VAPs in patients with osteoporosis. Only peer-reviewed published articles that fulfilled the criteria of being regarded as full economic evaluations including both morbidity and mortality in the outcome measure in the form of quality-adjusted life years (QALYs) were included. The search identified 949 studies, of which four (0.4 %) were identified as relevant with one study added later. The reviewed studies differed widely in terms of study design, modelling framework and data used, yielding different results and conclusions regarding the cost-effectiveness of VAPs. Three out of five studies indicated in the base case results that VAPs were cost effective compared to non-surgical management (NSM). The five main factors that drove the variations in the cost-effectiveness between the studies were time horizon, quality of life effect of treatment, offset time of the treatment effect, reduced number of bed days associated with VAPs and mortality benefit with treatment. The cost-effectiveness of VAPs is uncertain. In answering the remaining questions, new cost-effectiveness analysis will yield limited benefit. Rather, studies that can reduce the uncertainty in the underlying data, especially regarding the long-term clinical outcomes of VAPs, should be conducted.

Thoracolumbar spine loading associated with kinematics of the young and the elderly during activities of daily living.

PubMed

Ignasiak, Dominika; Rüeger, Andrea; Sperr, Ramona; Ferguson, Stephen J

2018-03-21

Excessive mechanical loading of the spine is a critical factor in vertebral fracture initiation. Most vertebral fractures develop spontaneously or due to mild trauma, as physiological loads during activities of daily living might exceed the failure load of osteoporotic vertebra. Spinal loading patterns are affected by vertebral kinematics, which differ between elderly and young individuals. In this study, the effects of age-related changes in spine kinematics on thoracolumbar spinal segmental loading during dynamic activities of daily living were investigated using combined experimental and modeling approach. Forty-four healthy volunteers were recruited into two age groups: young (N = 23, age = 27.1 ± 3.8) and elderly (N = 21, age = 70.1 ± 3.9). The spinal curvature was assessed with a skin-surface device and the kinematics of the spine and lower extremities were recorded during daily living tasks (flexion-extension and stand-sit-stand) with a motion capture system. The obtained data were used as input for a musculoskeletal model with a detailed thoracolumbar spine representation. To isolate the effect of kinematics on predicted loads, other model properties were kept constant. Inverse dynamics simulations were performed in the AnyBody Modeling System to estimate corresponding spinal loads. The maximum compressive loads predicted for the elderly motion patterns were lower than those of the young for L2/L3 and L3/L4 lumbar levels during flexion and for upper thoracic levels during stand-to-sit (T1/T2-T8/T9) and sit-to-stand (T3/T4-T6/T7). However, the maximum loads predicted for the lower thoracic levels (T9/T10-L1/L2), a common site of vertebral fractures, were similar compared to the young. Nevertheless, these loads acting on the vertebrae of reduced bone quality might contribute to a higher fracture risk for the elderly. Copyright © 2017 Elsevier Ltd. All rights reserved.

Delayed hypertrophic differentiation of epiphyseal chondrocytes contributes to failed secondary ossification in mucopolysaccharidosis VII dogs

PubMed Central

Peck, Sun H.; O'Donnell, Philip J.M.; Kang, Jennifer L.; Malhotra, Neil R.; Dodge, George R.; Pacifici, Maurizio; Shore, Eileen M.; Haskins, Mark E.; Smith, Lachlan J.

2015-01-01

Mucopolysaccharidosis (MPS) VII is a lysosomal storage disorder characterized by deficient β-glucuronidase activity, which leads to the accumulation of incompletely degraded glycosaminoglycans (GAGs). MPS VII patients present with severe skeletal abnormalities, which are particularly prevalent in the spine. Incomplete cartilage-to-bone conversion in MPS VII vertebrae during postnatal development is associated with progressive spinal deformity and spinal cord compression. The objectives of this study were to determine the earliest postnatal developmental stage at which vertebral bone disease manifests in MPS VII and to identify the underlying cellular basis of impaired cartilage-to-bone conversion, using the naturally-occurring canine model. Control and MPS VII dogs were euthanized at 9 and 14 days-of-age, and vertebral secondary ossification centers analyzed using micro-computed tomography, histology, qPCR, and protein immunoblotting. Imaging studies and mRNA analysis of bone formation markers established that secondary ossification commences between 9 and 14 days in control animals, but not in MPS VII animals. mRNA analysis of differentiation markers revealed that MPS VII epiphyseal chondrocytes are unable to successfully transition from proliferation to hypertrophy during this critical developmental window. Immunoblotting demonstrated abnormal persistence of Sox9 protein in MPS VII cells between 9 and 14 days-of-age, and biochemical assays revealed abnormally high intra and extracellular GAG content in MPS VII epiphyseal cartilage at as early as 9 days-of-age. In contrast, assessment of vertebral growth plates and primary ossification centers revealed no significant abnormalities at either age. The results of this study establish that failed vertebral bone formation in MPS VII can be traced to the failure of epiphyseal chondrocytes to undergo hypertrophic differentiation at the appropriate developmental stage, and suggest that aberrant processing of Sox9 protein may contribute to this cellular dysfunction. These results also highlight the importance of early diagnosis and therapeutic intervention to prevent the progression of debilitating skeletal disease in MPS patients. PMID:26422116

Effect of Augmentation Material Stiffness on Adjacent Vertebrae after Osteoporotic Vertebroplasty Using Finite Element Analysis with Different Loading Methods.

PubMed

Cho, Ah-Reum; Cho, Sang-Bong; Lee, Jae-Ho; Kim, Kyung-Hoon

2015-11-01

Vertebroplasty is an effective treatment for osteoporotic vertebral fractures, which are one of the most common fractures associated with osteoporosis. However, clinical observation has shown that the risk of adjacent vertebral body fractures may increase after vertebroplasty. The mechanism underlying adjacent vertebral body fracture after vertebroplasty is not clear; excessive stiffness resulting from polymethyl methacrylate has been suspected as an important mechanism. The aim of our study was to compare the effects of bone cement stiffness on adjacent vertebrae after osteoporotic vertebroplasty under load-controlled versus displacement-controlled conditions. An experimental computer study using a finite element analysis. Medical research institute, university hospital, Korean. A three-dimensional digital anatomic model of L1/2 bone structure was reconstructed from human computed tomographic images. The reconstructed three-dimensional geometry was processed for finite element analysis such as meshing elements and applying material properties. Two boundary conditions, load-controlled and displacement-controlled methods, were applied to each of 5 deformation modes: compression, flexion, extension, lateral bending, and torsion. The adjacent L1 vertebra, irrespective of augmentation, revealed nearly similar maximum von Mises stresses under the load-controlled condition. However, for the displacement-controlled condition, the maximum von Mises stresses in the cortical bone and inferior endplate of the adjacent L1 vertebra increased significantly after cement augmentation. This increase was more significant than that with stiffer bone cement under all modes, except the torsion mode. The finite element model was simplified, excluding muscular forces and incorporating a large volume of bone cement, to more clearly demonstrate effects of bone cement stiffness on adjacent vertebrae after vertebroplasty. Excessive stiffness of augmented bone cement increases the risk of adjacent vertebral fractures after vertebroplasty in an osteoporotic finite element model. This result was most prominently observed using the displacement-controlled method.

Biomechanical evaluation of a spherical lumbar interbody device at varying levels of subsidence.

PubMed

Rundell, Steven A; Isaza, Jorge E; Kurtz, Steven M

2011-01-01

Ulf Fernström implanted stainless steel ball bearings following discectomy, or for painful disc disease, and termed this procedure disc arthroplasty. Today, spherical interbody spacers are clinically available, but there is a paucity of associated biomechanical testing. The primary objective of the current study was to evaluate the biomechanics of a spherical interbody implant. It was hypothesized that implantation of a spherical interbody implant, with combined subsidence into the vertebral bodies, would result in similar ranges of motion (RoM) and facet contact forces (FCFs) when compared with an intact condition. A secondary objective of this study was to determine the effect of using a polyetheretherketone (PEEK) versus a cobalt chrome (CoCr) implant on vertebral body strains. We hypothesized that the material selection would have a negligible effect on vertebral body strains since both materials have elastic moduli substantially greater than the annulus. A finite element model of L3-L4 was created and validated by use of ROM, disc pressure, and bony strain from previously published data. Virtual implantation of a spherical interbody device was performed with 0, 2, and 4 mm of subsidence. The model was exercised in compression, flexion, extension, axial rotation, and lateral bending. The ROM, vertebral body effective (von Mises) strain, and FCFs were reported. Implantation of a PEEK implant resulted in slightly lower strain maxima when compared with a CoCr implant. For both materials, the peak strain experienced by the underlying bone was reduced with increasing subsidence. All levels of subsidence resulted in ROM and FCFs similar to the intact model. The results suggest that a simple spherical implant design is able to maintain segmental ROM and provide minimal differences in FCFs. Large areas of von Mises strain maxima were generated in the bone adjacent to the implant regardless of whether the implant was PEEK or CoCr.

Application of the SeDeM Diagram and a new mathematical equation in the design of direct compression tablet formulation.

PubMed

Suñé-Negre, Josep M; Pérez-Lozano, Pilar; Miñarro, Montserrat; Roig, Manel; Fuster, Roser; Hernández, Carmen; Ruhí, Ramon; García-Montoya, Encarna; Ticó, Josep R

2008-08-01

Application of the new SeDeM Method is proposed for the study of the galenic properties of excipients in terms of the applicability of direct-compression technology. Through experimental studies of the parameters of the SeDeM Method and their subsequent mathematical treatment and graphical expression (SeDeM Diagram), six different DC diluents were analysed to determine whether they were suitable for direct compression (DC). Based on the properties of these diluents, a mathematical equation was established to identify the best DC diluent and the optimum amount to be used when defining a suitable formula for direct compression, depending on the SeDeM properties of the active pharmaceutical ingredient (API) to be used. The results obtained confirm that the SeDeM Method is an appropriate system, effective tool for determining a viable formulation for tablets prepared by direct compression, and can thus be used as the basis for the relevant pharmaceutical development.

Dynamic control of a homogeneous charge compression ignition engine

DOEpatents

Duffy, Kevin P [Metamora, IL; Mehresh, Parag [Peoria, IL; Schuh, David [Peoria, IL; Kieser, Andrew J [Morton, IL; Hergart, Carl-Anders [Peoria, IL; Hardy, William L [Peoria, IL; Rodman, Anthony [Chillicothe, IL; Liechty, Michael P [Chillicothe, IL

2008-06-03

A homogenous charge compression ignition engine is operated by compressing a charge mixture of air, exhaust and fuel in a combustion chamber to an autoignition condition of the fuel. The engine may facilitate a transition from a first combination of speed and load to a second combination of speed and load by changing the charge mixture and compression ratio. This may be accomplished in a consecutive engine cycle by adjusting both a fuel injector control signal and a variable valve control signal away from a nominal variable valve control signal. Thereafter in one or more subsequent engine cycles, more sluggish adjustments are made to at least one of a geometric compression ratio control signal and an exhaust gas recirculation control signal to allow the variable valve control signal to be readjusted back toward its nominal variable valve control signal setting. By readjusting the variable valve control signal back toward its nominal setting, the engine will be ready for another transition to a new combination of engine speed and load.

Mechanical response of unidirectional boron/aluminum under combined loading

NASA Technical Reports Server (NTRS)

Becker, Wolfgang; Pindera, Marek-Jerzy; Herakovich, Carl T.

1987-01-01

Three test methods were employed to characterize the response of unidirectional Boron/Aluminum metal matrix composite material under monotonic and cyclic loading conditions, namely, losipescu shear, off-axis tension and compression. The characterization of the elastic and plastic response includes the elastic material properties, yielding and subsequent hardening of the unidirectional composite under different stress ratios in the material principal coordinate system. Yield loci generated for different stress ratios are compared for the three different test methods, taking into account residual stresses and specimen geometry. Subsequently, the yield locus for in-plane shear is compared with the prediction of an analytical, micromechanical model. The influence of the scatter in the experimental data on the predicted yield surface is also analyzed. Lastly, the experimental material strengths in tension and compression are correlated with the maximum stress and the Tsai-Wu failure criterion.

Data on the impact of increasing the W amount on the mass density and compressive properties of Ni-W alloys processed by spark plasma sintering.

PubMed

Sadat, T; Hocini, A; Lilensten, L; Faurie, D; Tingaud, D; Dirras, G

2016-06-01

Bulk Ni-W alloys having composite-like microstructures are processed by spark plasma sintering (SPS) route of Ni and W powder blends as reported in a recent study of Sadat et al. (2016) (DOI of original article: doi:10.1016/j.matdes.2015.10.083) [1]. The present dataset deals with determination of mass density and evaluation of room temperature compressive mechanical properties as function of the amount of W (%wt. basis). The presented data concern: (i) measurement of the mass of each investigated Ni-W alloy which is subsequently used to compute the mass density of the alloy and (ii) the raw (stress (MPa) and strain ([Formula: see text])) data, which can be subsequently used for stress/ strain plots.

Data on the impact of increasing the W amount on the mass density and compressive properties of Ni–W alloys processed by spark plasma sintering

PubMed Central

Sadat, T.; Hocini, A.; Lilensten, L.; Faurie, D.; Tingaud, D.; Dirras, G.

2016-01-01

Bulk Ni–W alloys having composite-like microstructures are processed by spark plasma sintering (SPS) route of Ni and W powder blends as reported in a recent study of Sadat et al. (2016) (DOI of original article: doi:10.1016/j.matdes.2015.10.083) [1]. The present dataset deals with determination of mass density and evaluation of room temperature compressive mechanical properties as function of the amount of W (%wt. basis). The presented data concern: (i) measurement of the mass of each investigated Ni–W alloy which is subsequently used to compute the mass density of the alloy and (ii) the raw (stress (MPa) and strain (ΔLL0)) data, which can be subsequently used for stress/ strain plots. PMID:27158658

Studying the compactibility of the VT22 high-strength alloy powder obtained by the PREP method

NASA Astrophysics Data System (ADS)

Kryuchkov, D. I.; Berezin, I. M.; Nesterenko, A. V.; Zalazinsky, A. G.; Vichuzhanin, D. I.

2017-12-01

Compression curves are plotted for VT22 high-strength alloy powder under conditions of uniaxial compression at room temperature. The density of the compacted briquette at the loading and unloading stages is determined. It is demonstrated that strong interparticle bonds are formed in the area of the action of shear deformation. The results are supposed to be used to identify the flow model of the material studied and to perform the subsequent numerical modeling of the compaction process.

The phylogeny and ontogeny of autonomic control of the heart and cardiorespiratory interactions in vertebrates.

PubMed

Taylor, Edwin W; Leite, Cleo A C; Sartori, Marina R; Wang, Tobias; Abe, Augusto S; Crossley, Dane A

2014-03-01

Heart rate in vertebrates is controlled by activity in the autonomic nervous system. In spontaneously active or experimentally prepared animals, inhibitory parasympathetic control is predominant and is responsible for instantaneous changes in heart rate, such as occur at the first air breath following a period of apnoea in discontinuous breathers like inactive reptiles or species that surface to air breathe after a period of submersion. Parasympathetic control, exerted via fast-conducting, myelinated efferent fibres in the vagus nerve, is also responsible for beat-to-beat changes in heart rate such as the high frequency components observed in spectral analysis of heart rate variability. These include respiratory modulation of the heartbeat that can generate cardiorespiratory synchrony in fish and respiratory sinus arrhythmia in mammals. Both may increase the effectiveness of respiratory gas exchange. Although the central interactions generating respiratory modulation of the heartbeat seem to be highly conserved through vertebrate phylogeny, they are different in kind and location, and in most species are as yet little understood. The heart in vertebrate embryos possesses both muscarinic cholinergic and β-adrenergic receptors very early in development. Adrenergic control by circulating catecholamines seems important throughout development. However, innervation of the cardiac receptors is delayed and first evidence of a functional cholinergic tonus on the heart, exerted via the vagus nerve, is often seen shortly before or immediately after hatching or birth, suggesting that it may be coordinated with the onset of central respiratory rhythmicity and subsequent breathing.

Epidemiological burden of postmenopausal osteoporosis in Italy from 2010 to 2020: estimations from a disease model.

PubMed

Piscitelli, P; Brandi, M; Cawston, H; Gauthier, A; Kanis, J A; Compston, J; Borgström, F; Cooper, C; McCloskey, E

2014-11-01

The article describes the adaptation of a model to estimate the burden of postmenopausal osteoporosis in women aged 50 years and over in Italy between 2010 and 2020. For this purpose, a validated postmenopausal osteoporosis disease model developed for Sweden was adapted to Italy. For each year of the study, the 'incident cohort' (women experiencing a first osteoporotic fracture) was identified and run through a Markov model using 1-year cycles until 2020. Health states were based on the number of fractures and deaths. Fracture by site (hip, clinical vertebral, non-hip non-vertebral) was tracked for each health state. Transition probabilities reflected fracture site-specific risk of death and subsequent fractures. Model inputs specific to Italy included population size and life tables from 1970 to 2020, incidence of hip fracture and BMD by age in the general population (mean and standard deviation). The model estimated that the number of postmenopausal osteoporotic women would increase from 3.3 million to 3.7 million between 2010 and 2020 (+14.3%). Assuming unchanged incidence rates by age group over time, the model predicted the overall number of osteoporotic fractures to increase from 285.0 to 335.8 thousand fractures between 2010 and 2020 (+17.8%). The estimated expected increases in hip, vertebral and non-hip non-vertebral fractures were 22.3, 17.2 and 16.3%, respectively. Due to demographic changes, the burden of fractures is expected to increase markedly by 2020.

Identification, cloning, and sequencing of a fragment of Amsacta moorei entomopoxvirus DNA containing the spheroidin gene and three vaccinia virus-related open reading frames.

PubMed Central

Hall, R L; Moyer, R W

1991-01-01

Entomopoxvirus virions are frequently contained within crystalline occlusion bodies, which are composed of primarily a single protein, spheroidin, which is analogous to the polyhedrin protein of baculovirus. The spheroidin gene of Amsacta moorei entomopoxvirus was identified following the microsequencing of polypeptides generated from cyanogen bromide treatment of spheroidin and the subsequent synthesis of oligonucleotide hybridization probes. DNA sequencing of a 6.8-kb region of DNA containing the spheroidin gene showed that the spheroidin protein is derived from a 3.0-kb open reading frame potentially encoding a protein of 115 kDa. Three copies of the heptanucleotide, TTTTTNT, a sequence associated with early gene transcription in the vertebrate poxviruses, and four in-frame translational termination signals were found within 60 bp upstream of the putative spheroidin gene promoter (TAAATG). The spheroidin gene promoter region contains the sequence TAAATG, which is found in many late promoters of the vertebrate poxviruses and which serves as the site of transcriptional initiation, as shown by primer extension. Primer extension experiments also showed that spheroidin gene transcripts contain 5' poly(A) sequences typical of vertebrate poxvirus late transcripts. The 92 bases upstream of the initiating TAAATG are unusually A + T rich and contain only 7 G or C residues. An analysis of open reading frames around the spheroidin gene suggests that the colinear core of "essential genes" typical of the vertebrate poxviruses is absent in A. moorei entomopoxvirus. Images PMID:1942245

Beauty parlor stroke syndrome due to a bone fragment from an osteophyte of the atlas: case report.

PubMed

Kameda, Takuya; Otani, Koji; Tamura, Takamitsu; Konno, Shinichi

2018-04-01

Beauty parlor stroke syndrome (BPSS) is a rare condition characterized by mechanical impingement of a vertebral artery (VA) during neck rotation and/or hyperextension followed by vertebrobasilar insufficiency. However, there have been no reports of BPSS in which the cause of mechanical impingement was identified and no cases for which surgical treatment was reported. The authors report the case of a 56-year-old Japanese man who presented with presyncope that occurred during cervical extension. Given the possibility of vertebrobasilar insufficiency, digital subtraction angiography and CT angiography were performed. These studies revealed that the right VA was hypoplastic and the left VA was dominant. Moreover, in the position of cervical extension, the dominant left VA showed constriction caused by a bone fragment of an osteophyte of the atlas. Removal of the bone fragment was performed. Postoperative left vertebral angiography showed improvement of blood flow in the extended position, and the presyncope completely disappeared. The pathomechanism of this case was a bone fragment compressing the left VA in the C-1 groove during neck extension. In BPSS patients with recurrent transient symptoms, the possibility of this mechanism of VA constriction by a free bone fragment should be considered.

Lasp1 misexpression influences chondrocyte differentiation in the vertebral column.

PubMed

Hermann-Kleiter, Natascha; Ghaffari-Tabrizi, Nassim; Blumer, Michael J F; Schwarzer, Christoph; Mazur, Magdalena A; Artner, Isabella

2009-01-01

The mouse mutant wavy tail Tg(Col1a1-lacZ)304ng was created through transgene insertion and exhibits defects of the vertebral column. Homozygous mutant animals have compressed tail vertebrae and wedge-shaped intervertebral discs, resulting in a meandering tail. Delayed closure of lumbar neural arches and lack of processus spinosi have been observed; these defects become most prominent during the transition from cartilage to bone. The spina bifida was resistant to folic acid treatment, while retinoic acid administration caused severe skeletal defects in the mutant, but none in wild type control animals. The transgene integrated at chromosome 11 band D, in an area of high gene density. The insertion site was located between the transcription start sites of the Rpl23 and Lasp1 genes. LASP1 (an actin binding protein involved in cell migration and survival) was found to be produced in resting and hypertrophic chondrocytes in the vertebrae. In mutant vertebrae, temporal and spatial misexpression of Lasp1 was observed, indicating that alterations in Lasp1 transcription are most likely responsible for the observed phenotype. These data reveal a yet unappreciated role of Lasp1 in chondrocyte differentiation during cartilage to bone transition.

Spiral swimming behavior due to cranial and vertebral lesions associated with Cytophaga psychrophila infections in salmonid fishes

USGS Publications Warehouse

Kent, M.L.; Groff, J.M.; Morrison, J.K.; Yasutake, W.T.; Holt, R.A.

1989-01-01

C. psychrophila infections of the cranium and anterior vertebrae in salmonid fishes were associated with ataxia, spiral swimming along the axis of the fish, and death. The syndrome was observed in 2-10% of underyearling coho salmon Oncorhynchus kisutch, rainbow troutSalmo gairdneri, and steelhead trout S. gairdneri at several private, state, and federal hatcheries in Washington and Oregon, USA, between 1963 and 1987. Affected fish did not recover and ultimately died. Histological examination consistently revealed subacute to chronic periostitis, osteitis, meningitis, and ganglioneuritis. Inflammation and periosteal proliferation of the anterior vertebrae at the junction of the vertebral column with the cranium with extension into the cranial case was a consistent feature. The adjacent nervous tissue, particularly the medulla, was often compressed by the proliferative lesion, and this may have caused the ataxia. Though bacteria were seldom observed in these lesions. C. psychrophilawas isolated in culture from the cranial cavity of all affected fish that were tested. Epidemiological observations suggested that this bacterium is the causative agent because the spiral swimming behaviour and lesions were observed only in populations that had recovered from acute C. psychrophila infections.

Shedding light into the function of the earliest vertebrate skeleton

NASA Astrophysics Data System (ADS)

Martinez-Perez, Carlos; Purnell, Mark; Rayfield, Emily; Donoghue, Philip

2016-04-01

Conodonts are an extinct group of jawless vertebrates, the first in our evolutionary lineage to develop a biomineralized skeleton. As such, the conodont skeleton is of great significance because of the insights it provides concerning the biology and function of the primitive vertebrate skeleton. Conodont function has been debated for a century and a half on the basis of its paleocological importance in the Palaezoic ecosystems. However, due to the lack of extanct close representatives and the small size of the conodont element (under a milimiter in length) strongly limited their functional analysis, traditional restricted to analogy. More recently, qualitative approaches have been developed, facilitating tests of element function based on occlusal performance and analysis of microwear and microstructure. In this work we extend these approaches using novel quantitative experimental methods including Synchrotron Radiation X-ray Tomographic Microscopy or Finite Element Analysis to test hypotheses of conodont function. The development of high resolution virtual models of conodont elements, together with biomechanical approaches using Finite Element analysis, informed by occlusal and microwear analyses, provided conclusive support to test hypothesis of structural adaptation within the crown tissue microstructure, showing a close topological co-variation patterns of compressive and tensile stress distribution with different crystallite orientation. In addition, our computational analyses strongly support a tooth-like function for many conodont species. Above all, our study establishes a framework (experimental approach) in which the functional ecology of conodonts can be read from their rich taxonomy and phylogeny, representing an important attempt to understand the role of this abundant and diverse clade in the Phanerozoic marine ecosystems.

Correlation between surface topography and lubricant migration in steel sheets for the autobody manufacturing process

NASA Astrophysics Data System (ADS)

Benati, F.; Sacerdotti, F.; Griffiths, B. J.; Butler, C.; Karila, J. M.; Vermeulen, M.; Holtkamp, H.; Gatti, S.

2002-05-01

Material for the production of autobody panels is usually dispatched in the form of coils. Because of their weight, they tend to `compress' the lubricant applied for rust protection and some of it leaks from the coil. Those areas affected by lubricant starvation are known as `dry-spots' and are a cause of a number of product rejections during the subsequent forming operation. A test was deployed with the combined work of Ocas, CORUS IJmuiden and Renault that proved that surface topography controls, amongst other factors, affects lubricant migration. The test consists of compressing a stack of lubricated steel sheets at known pressure for a known time using different lubricants in different amounts. It was observed that, because of the `compression', the lubricant tends to migrate to the side of the sheet, and its migration was quantified using a Fischer Betascope MMS module. Analysis consisted of analysis of variance on several designs of experiments and subsequent correlation with surface topography 3D parameters. These experiments showed the importance of standard amplitude surface parameters and new closed area surface parameters to characterize lubricant migration under pressure.

Is breast compression associated with breast cancer detection and other early performance measures in a population-based breast cancer screening program?

PubMed

Moshina, Nataliia; Sebuødegård, Sofie; Hofvind, Solveig

2017-06-01

We aimed to investigate early performance measures in a population-based breast cancer screening program stratified by compression force and pressure at the time of mammographic screening examination. Early performance measures included recall rate, rates of screen-detected and interval breast cancers, positive predictive value of recall (PPV), sensitivity, specificity, and histopathologic characteristics of screen-detected and interval breast cancers. Information on 261,641 mammographic examinations from 93,444 subsequently screened women was used for analyses. The study period was 2007-2015. Compression force and pressure were categorized using tertiles as low, medium, or high. χ 2 test, t tests, and test for trend were used to examine differences between early performance measures across categories of compression force and pressure. We applied generalized estimating equations to identify the odds ratios (OR) of screen-detected or interval breast cancer associated with compression force and pressure, adjusting for fibroglandular and/or breast volume and age. The recall rate decreased, while PPV and specificity increased with increasing compression force (p for trend <0.05 for all). The recall rate increased, while rate of screen-detected cancer, PPV, sensitivity, and specificity decreased with increasing compression pressure (p for trend <0.05 for all). High compression pressure was associated with higher odds of interval breast cancer compared with low compression pressure (1.89; 95% CI 1.43-2.48). High compression force and low compression pressure were associated with more favorable early performance measures in the screening program.

Postoperative re-irradiation using stereotactic body radiotherapy for metastatic epidural spinal cord compression.

PubMed

Ito, Kei; Nihei, Keiji; Shimizuguchi, Takuya; Ogawa, Hiroaki; Furuya, Tomohisa; Sugita, Shurei; Hozumi, Takahiro; Keisuke Sasai; Karasawa, Katsuyuki

2018-06-15

OBJECTIVE This study aimed to clarify the outcomes of postoperative re-irradiation using stereotactic body radiotherapy (SBRT) for metastatic epidural spinal cord compression (MESCC) in the authors' institution and to identify factors correlated with local control. METHODS Cases in which patients with previously irradiated MESCC underwent decompression surgery followed by spine SBRT as re-irradiation between April 2013 and May 2017 were retrospectively reviewed. The surgical procedures were mainly performed by the posterior approach and included decompression and fixation. The prescribed dose for spine SBRT was 24 Gy in 2 fractions. The primary outcome was local control, which was defined as elimination, shrinkage, or no change of the tumor on CT or MRI obtained approximately every 3 months after SBRT. In addition, various patient-, treatment-, and tumor-specific factors were evaluated to determine their predictive value for local control. RESULTS Twenty-eight cases were identified in the authors' institutional databases as meeting the inclusion criteria. The histology of the primary disease was thyroid cancer in 7 cases, lung cancer in 6, renal cancer in 3, colorectal cancer in 3, and other cancers in 9. The most common previous radiation dose was 30 Gy in 10 fractions (15 cases). The mean interval since the most recent irradiation was 16 months (range 5-132 months). The median duration of follow-up after SBRT was 13 months (range 4-38 months). The 1-year local control rate was 70%. In the analysis of factors related to local control, Bilsky grade, number of vertebral levels in the treatment target, the interval between the latest radiotherapy and SBRT, recursive partitioning analysis (RPA), the prognostic index for spinal metastases (PRISM), and the revised Tokuhashi score were not significantly correlated with local control. The favorable group classified by the Rades prognostic score achieved a significantly higher 1-year local control rate than the unfavorable group (1-year local control rate: 100% vs 33%; p < 0.01). Radiation-induced myelopathy and vertebral compression fracture were observed in 1 and 3 patients, respectively. No other grade 3 or greater toxicities were encountered. CONCLUSIONS The results indicate that spine SBRT as postoperative re-irradiation was effective, and it was especially useful for patients classified as having a good survival prognosis according to the Rades score.

Some new conceptions in the approach to harnessing tidal energy

NASA Astrophysics Data System (ADS)

Gorlov, A. M.

A method of converting ocean tide energy into compressed air energy for subsequent conversion to electrical and other forms of industrial energy is presented. The tidal energy is converted to compressed air energy by means of specialized chambers which are put on the ocean bed. Ocean water from the dammed region passes through the chamber where it works as a natural piston compressing air in the upper part of the closure. The compressed air can be expanded through high speed compact gas turbines or any type of reciprocating engine. The flexible reinforced plastic barrier should be substantially cheaper than a conventional rigid dam and can be designed so that by means of special floats it becomes a self-supported and self-regulated weightless structural system which can dam a large shallow space of ocean without having to be connected to special bays.

[Biomaterials in bone repair].

PubMed

Puska, Mervi; Aho, Allan J; Vallittu, Pekka K

2013-01-01

In orthopedics, traumatology, and craniofacial surgery, biomaterials should meet the clinical demands of bone that include shape, size and anatomical location of the defect, as well as the physiological load-bearing stresses. Biomaterials are metals, ceramics, plastics or materials of biological origin. In the treatment of large defects, metallic endoprostheses or bone grafts are employed, whereas ceramics in the case of small defects. Plastics are employed on the artificial joint surfaces, in the treatment of vertebral compression fractures, and as biodegradable screws and plates. Porosity, bioactivity, and identical biomechanics to bone are fundamental for achieving a durable, well-bonded, interface between biomaterial and bone. In the case of severe bone treatments, biomaterials should also imply an option to add biologically active substances.

Invasive histiocytic sarcoma of the lumbar spine in a ferret (Mustela putorius furo).

PubMed

Warschau, M; Hoffmann, M; Dziallas, P; Hansmann, F; Baumgärtner, W; Mischke, R; Cichowski, S; Fehr, M

2017-02-01

This report describes the history, clinical examination and histopathology of a histiocytic sarcoma in a domestic ferret. Clinical signs were acute paraplegia and dysuria. Physical examination revealed a firm, smooth, touch-sensitive mass in and around the lumbar vertebral column. Neurologic examination was consistent with a lesion between spinal cord segments T3 and L3. Magnetic resonance images revealed bone lesions of L2 and L3 combined with compression of the spinal cord due to a homogenous, isointense mass that was diagnosed as a malignant round cell tumour and the ferret was euthanased. Histopathology confirmed the diagnosis of an infiltrative histiocytic sarcoma. © 2017 British Small Animal Veterinary Association.

The chick embryo: a leading model in somitogenesis studies.

PubMed

Pourquié, Olivier

2004-09-01

The vertebrate body is built on a metameric organization which consists of a repetition of functionally equivalent units, each comprising a vertebra, its associated muscles, peripheral nerves and blood vessels. This periodic pattern is established during embryogenesis by the somitogenesis process. Somites are generated in a rhythmic fashion from the presomitic mesoderm and they subsequently differentiate to give rise to the vertebrae and skeletal muscles of the body. Somitogenesis has been very actively studied in the chick embryo since the 19th century and many of the landmark experiments that led to our current understanding of the vertebrate segmentation process have been performed in this organism. Somite formation involves an oscillator, the segmentation clock whose periodic signal is converted into the periodic array of somite boundaries by a spacing mechanism relying on a traveling threshold of FGF signaling regressing in concert with body axis extension.

Spine Patterning Is Guided by Segmentation of the Notochord Sheath.

PubMed

Wopat, Susan; Bagwell, Jennifer; Sumigray, Kaelyn D; Dickson, Amy L; Huitema, Leonie F A; Poss, Kenneth D; Schulte-Merker, Stefan; Bagnat, Michel

2018-02-20

The spine is a segmented axial structure made of alternating vertebral bodies (centra) and intervertebral discs (IVDs) assembled around the notochord. Here, we show that, prior to centra formation, the outer epithelial cell layer of the zebrafish notochord, the sheath, segments into alternating domains corresponding to the prospective centra and IVD areas. This process occurs sequentially in an anteroposterior direction via the activation of Notch signaling in alternating segments of the sheath, which transition from cartilaginous to mineralizing domains. Subsequently, osteoblasts are recruited to the mineralized domains of the notochord sheath to form mature centra. Tissue-specific manipulation of Notch signaling in sheath cells produces notochord segmentation defects that are mirrored in the spine. Together, our findings demonstrate that notochord sheath segmentation provides a template for vertebral patterning in the zebrafish spine. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Distinct patterns of notochord mineralization in zebrafish coincide with the localization of Osteocalcin isoform 1 during early vertebral centra formation

PubMed Central

2012-01-01

Background In chondrichthyans, basal osteichthyans and tetrapods, vertebral bodies have cartilaginous anlagen that subsequently mineralize (chondrichthyans) or ossify (osteichthyans). Chondrocytes that form the vertebral centra derive from somites. In teleost fish, vertebral centrum formation starts in the absence of cartilage, through direct mineralization of the notochord sheath. In a second step, the notochord is surrounded by somite-derived intramembranous bone. In several small teleost species, including zebrafish (Danio rerio), even haemal and neural arches form directly as intramembranous bone and only modified caudalmost arches remain cartilaginous. This study compares initial patterns of mineralization in different regions of the vertebral column in zebrafish. We ask if the absence or presence of cartilaginous arches influences the pattern of notochord sheath mineralization. Results To reveal which cells are involved in mineralization of the notochord sheath we identify proliferating cells, we trace mineralization on the histological level and we analyze cell ultrastructure by TEM. Moreover, we localize proteins and genes that are typically expressed by skeletogenic cells such as Collagen type II, Alkaline phosphatase (ALP) and Osteocalcin (Oc). Mineralization of abdominal and caudal vertebrae starts with a complete ring within the notochord sheath and prior to the formation of the bony arches. In contrast, notochord mineralization of caudal fin centra starts with a broad ventral mineral deposition, associated with the bases of the modified cartilaginous arches. Similar, arch-related, patterns of mineralization occur in teleosts that maintain cartilaginous arches throughout the spine. Throughout the entire vertebral column, we were able to co-localize ALP-positive signal with chordacentrum mineralization sites, as well as Collagen II and Oc protein accumulation in the mineralizing notochord sheath. In the caudal fin region, ALP and Oc signals were clearly produced both by the notochord epithelium and cells outside the notochord, the cartilaginous arches. Based on immunostaining, real time PCR and oc2:gfp transgenic fish, we identify Oc in the mineralizing notochord sheath as osteocalcin isoform 1 (Oc1). Conclusions If notochord mineralization occurs prior to arch formation, mineralization of the notochord sheath is ring-shaped. If notochord mineralization occurs after cartilaginous arch formation, mineralization of the notochord sheath starts at the insertion point of the arches, with a basiventral origin. The presence of ALP and Oc1, not only in cells outside the notochord, but also in the notochord epithelium, suggests an active role of the notochord in the mineralization process. The same may apply to Col II-positive chondrocytes of the caudalmost haemal arches that show ALP activity and Oc1 accumulation, since these chondrocytes do not mineralize their own cartilage matrix. Even without cartilaginous preformed vertebral centra, the cartilaginous arches may have an inductive role in vertebral centrum formation, possibly contributing to the distinct mineralization patterns of zebrafish vertebral column and caudal fin vertebral fusion. PMID:23043290

Distinct patterns of notochord mineralization in zebrafish coincide with the localization of Osteocalcin isoform 1 during early vertebral centra formation.

PubMed

Bensimon-Brito, Anabela; Cardeira, João; Cancela, Maria Leonor; Huysseune, Ann; Witten, Paul Eckhard

2012-10-09

In chondrichthyans, basal osteichthyans and tetrapods, vertebral bodies have cartilaginous anlagen that subsequently mineralize (chondrichthyans) or ossify (osteichthyans). Chondrocytes that form the vertebral centra derive from somites. In teleost fish, vertebral centrum formation starts in the absence of cartilage, through direct mineralization of the notochord sheath. In a second step, the notochord is surrounded by somite-derived intramembranous bone. In several small teleost species, including zebrafish (Danio rerio), even haemal and neural arches form directly as intramembranous bone and only modified caudalmost arches remain cartilaginous. This study compares initial patterns of mineralization in different regions of the vertebral column in zebrafish. We ask if the absence or presence of cartilaginous arches influences the pattern of notochord sheath mineralization. To reveal which cells are involved in mineralization of the notochord sheath we identify proliferating cells, we trace mineralization on the histological level and we analyze cell ultrastructure by TEM. Moreover, we localize proteins and genes that are typically expressed by skeletogenic cells such as Collagen type II, Alkaline phosphatase (ALP) and Osteocalcin (Oc). Mineralization of abdominal and caudal vertebrae starts with a complete ring within the notochord sheath and prior to the formation of the bony arches. In contrast, notochord mineralization of caudal fin centra starts with a broad ventral mineral deposition, associated with the bases of the modified cartilaginous arches. Similar, arch-related, patterns of mineralization occur in teleosts that maintain cartilaginous arches throughout the spine.Throughout the entire vertebral column, we were able to co-localize ALP-positive signal with chordacentrum mineralization sites, as well as Collagen II and Oc protein accumulation in the mineralizing notochord sheath. In the caudal fin region, ALP and Oc signals were clearly produced both by the notochord epithelium and cells outside the notochord, the cartilaginous arches. Based on immunostaining, real time PCR and oc2:gfp transgenic fish, we identify Oc in the mineralizing notochord sheath as osteocalcin isoform 1 (Oc1). If notochord mineralization occurs prior to arch formation, mineralization of the notochord sheath is ring-shaped. If notochord mineralization occurs after cartilaginous arch formation, mineralization of the notochord sheath starts at the insertion point of the arches, with a basiventral origin. The presence of ALP and Oc1, not only in cells outside the notochord, but also in the notochord epithelium, suggests an active role of the notochord in the mineralization process. The same may apply to Col II-positive chondrocytes of the caudalmost haemal arches that show ALP activity and Oc1 accumulation, since these chondrocytes do not mineralize their own cartilage matrix. Even without cartilaginous preformed vertebral centra, the cartilaginous arches may have an inductive role in vertebral centrum formation, possibly contributing to the distinct mineralization patterns of zebrafish vertebral column and caudal fin vertebral fusion.

Lumbar vertebrae fracture injury risk in finite element reconstruction of CIREN and NASS frontal motor vehicle crashes.

PubMed

Jones, Derek A; Gaewsky, James P; Kelley, Mireille E; Weaver, Ashley A; Miller, Anna N; Stitzel, Joel D

2016-09-01

The objective of this study was to reconstruct 4 real-world motor vehicle crashes (MVCs), 2 with lumbar vertebral fractures and 2 without vertebral fractures in order to elucidate the MVC and/or restraint variables that increase this injury risk. A finite element (FE) simplified vehicle model (SVM) was used in conjunction with a previously developed semi-automated tuning method to arrive at 4 SVMs that were tuned to mimic frontal crash responses of a 2006 Chevrolet Cobalt, 2012 Ford Escape, 2007 Hummer H3, and 2002 Chevrolet Cavalier. Real-world crashes in the first 2 vehicles resulted in lumbar vertebrae fractures, whereas the latter 2 did not. Once each SVM was tuned to its corresponding vehicle, the Total HUman Model for Safety (THUMS) v4.01 was positioned in 120 precrash configurations in each SVM by varying 5 parameters using a Latin hypercube design (LHD) of experiments: seat track position, seatback angle, steering column angle, steering column telescoping position, and d-ring height. For each case, the event data recorder (EDR) crash pulse was used to apply kinematic boundary conditions to the model. By analyzing cross-sectional vertebral loads, vertebral bending moments, and maximum principal strain and stress in both cortical and trabecular bone, injury metric response as a function of posture and restraint parameters was computed. Tuning the SVM to specific vehicle models produced close matches between the simulated and experimental crash test responses for head, T6, and pelvis resultant acceleration; left and right femur loads; and shoulder and lap belt loads. Though vertebral load in the THUMS simulations was highly similar between injury cases and noninjury cases, the amount of bending moment was much higher for the injury cases. Seatback angle had a large effect on the maximum compressive load and bending moment in the lumbar spine, indicating the upward tilt of the seat pan in conjunction with precrash positioning may increase the likelihood of suffering lumbar injury even in frontal, planar MVCs. In conclusion, precrash positioning has a large effect on lumbar injury metrics. The lack of lumbar injury criteria in regulatory crash tests may have led to inadvertent design of seat pans that work to apply axial force to the spinal column during frontal crashes.

Cost-Effectiveness Analysis of Percutaneous Vertebroplasty for Osteoporotic Compression Fractures.

PubMed

Takura, Tomoyuki; Yoshimatsu, Misako; Sugimori, Hiroki; Takizawa, Kenji; Furumatsu, Yoshiyuki; Ikeda, Hirotaka; Kato, Hiroshi; Ogawa, Yukihisa; Hamaguchi, Shingo; Fujikawa, Atsuko; Satoh, Toshihiko; Nakajima, Yasuo

2017-04-01

Single-center, single-arm, prospective time-series study. To assess the cost-effectiveness and improvement in quality of life (QOL) of percutaneous vertebroplasty (PVP). PVP is known to relieve back pain and increase QOL for osteoporotic compression fractures. However, the economic value of PVP has never been evaluated in Japan where universal health care system is adopted. We prospectively followed up 163 patients with acute vertebral osteoporotic compression fractures, 44 males aged 76.4±6.0 years and 119 females aged 76.8±7.1 years, who underwent PVP. To measure health-related QOL and pain during 52 weeks observation, we used the European Quality of Life-5 Dimensions (EQ-5D), the Rolland-Morris Disability Questionnaire (RMD), the 8-item Short-Form health survey (SF-8), and visual analogue scale (VAS). Quality-adjusted life years (QALY) were calculated using the change of health utility of EQ-5D. The direct medical cost was calculated by accounting system of the hospital and Japanese health insurance system. Cost-effectiveness was analyzed using incremental cost-effectiveness ratio (ICER): Δ medical cost/Δ QALY. After PVP, improvement in EQ-5D, RMD, SF-8, and VAS scores were observed. The gain of QALY until 52 weeks was 0.162. The estimated lifetime gain of QALY reached 1.421. The direct medical cost for PVP was ¥286,740 (about 3061 US dollars). Cost-effectiveness analysis using ICER showed that lifetime medical cost for a gain of 1 QALY was ¥201,748 (about 2154 US dollars). Correlations between changes in EQ-5D scores and other parameters such as RMD, SF-8, and VAS were observed during most of the study period, which might support the reliability and applicability to measure health utilities by EQ-5D for osteoporotic compression fractures in Japan as well. PVP may improve QOL and ameliorate pain for acute osteoporotic compression fractures and be cost-effective in Japan.

Compressive myelopathy in severe angular kyphosis: a series of ten patients.

PubMed

Zhang, Zhengfeng; Wang, Honggang; Liu, Chao

2016-06-01

Compressive myelopathy in severe angular kyphosis is rare and challenging for surgical treatment. The goal of this retrospective study was to report a series of ten patients with compressive myelopathy in severe angular kyphosis and the results of surgical decompression and correction of kyphosis. Between 2010 and 2014, 10 patients were surgically treated for severe angular kyphosis with a progressive onset or a sudden onset of paraplegia in investigator group. In these ten patients (seven males and three females), the etiologic diagnosis included eight cases of congenital kyphosis and two of neurofibromatosis; the distribution of spine level was from C5 to T11; the duration from onset until surgery ranged from 1 to 120 months; follow-up ranged from 12 to 26 months (mean 18.5 months); the kyphosis angle of the patients ranged from 50° to 180°. Magnetic resonance imaging demonstrated the spinal cord thinning and compression at apex in most of patients. All patients underwent decompressive surgery by single-stage posterior vertebral column resection or both anterior corpectomy fusion and posterior fixation. Neurological status was evaluated using the ASIA impairment classification and the motor score. Postoperatively, all patients had different kyphosis correction rate from 24 to 100 %. Nine patients showed neurological improvement; one patient showed no improvement. Among them, one sudden onset ASIA A adolescent paraplegic patient improved to ASIA E within 1 year of follow-up. One ASIA C adolescent paraplegic patients deteriorated neurologically to ASIA A after surgery and improved to ASIA D with 12-month follow-up. Compressive myelopathy in severe angular congenital kyphosis is usually occurred high incidence rate at apex of upper thoracic spine (T1-T4). The duration from onset of paraplegia until surgery and the severity of paraplegia before surgery are two key factors for neurological prognosis after surgery.

Conservation of globin genes in the "living fossil" Latimeria chalumnae and reconstruction of the evolution of the vertebrate globin family.

PubMed

Schwarze, Kim; Burmester, Thorsten

2013-09-01

The (hemo-)globins are among the best-investigated proteins in biomedical sciences. These small heme-proteins play an important role in oxygen supply, but may also have other functions. In addition to well known hemoglobin and myoglobin, six other vertebrate globin types have been identified in recent years: neuroglobin, cytoglobin, globin E, globin X, globin Y, and androglobin. Analyses of the genome of the "living fossil" Latimeria chalumnae show that the coelacanth is the only known vertebrate that includes all eight globin types. Thus, Latimeria can also be considered as a "globin fossil". Analyses of gene synteny and phylogenetic reconstructions allow us to trace the evolution and the functional changes of the vertebrate globin family. Neuroglobin and globin X diverged from the other globin types before the separation of Protostomia and Deuterostomia. The cytoglobins, which are unlikely to be involved in O2 supply, form the earliest globin branch within the jawed vertebrates (Gnathostomata), but do not group with the agnathan hemoglobins, as it has been proposed before. There is strong evidence from phylogenetic reconstructions and gene synteny that the eye-specific globin E and muscle-specific myoglobin constitute a common clade, suggesting a similar role in intracellular O2 supply. Latimeria possesses two α- and two β-hemoglobin chains, of which one α-chain emerged prior to the divergence of Actinopterygii and Sarcopterygii, but has been retained only in the coelacanth. Notably, the embryonic hemoglobin α-chains of Gnathostomata derive from a common ancestor, while the embryonic β-chains - with the exception of a more complex pattern in the coelacanth and amphibians - display a clade-specific evolution. Globin Y is associated with the hemoglobin gene cluster, but its phylogenetic position is not resolved. Our data show an early divergence of distinct globin types in the vertebrate evolution before the emergence of tetrapods. The subsequent loss of globins in certain taxa may be associated with changes in the oxygen-dependent metabolism. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins. Copyright © 2013 Elsevier B.V. All rights reserved.

Sublaminar fixation for traumatic lumbar fracture subluxation with lateral listhesis in a 2-year-old patient.

PubMed

Yanni, Daniel S; Cruz, Aurora S; Halim, Alexander Y; Gill, Amandip S; Muhonen, Michael G; Heary, Robert F; Goldstein, Ira M

2018-05-04

Pediatric spinal trauma can present a surgeon with difficult management decisions given the rarity of these cases, pediatric anatomy, and a growing spine. The need to stabilize a traumatically unstable pediatric spine can be an operative challenge given the lack of instrumentation available. The authors present a surgical technique and an illustrative case that may offer a novel, less disruptive method of stabilization. A 2-year-old girl presented after an assault with an L1-2 fracture subluxation with lateral listhesis and fractured jumped facets exhibited on CT scans. CT also showed intact growth plates at the vertebral body, pedicles, and posterior elements. MRI showed severe ligamentous injury, conus medullaris compression, and an epidural hematoma. Neurologically, the patient moved both lower extremities asymmetrically. Given the severity of the deformity and neurological examination and disruption of the stabilizing structures, the authors made the decision to surgically decompress the L-1 and L-2 segments with bilateral laminotomies, evacuate the epidural hematoma, and reduce the deformity with sublaminar stabilization using braided polyester cables bilaterally, thus preserving the growth plates. They also performed a posterolateral onlay fusion at L-1 and L-2 using autograft and allograft placed due to the facet disruption. At the 42-month follow-up, imaging showed fusion of L-1 and L-2 with good alignment, and the hardware was subsequently explanted. The patient was neurologically symmetric in strength, ambulating, and had preserved alignment. Her bones and spinal canal continued to grow in relation to the other levels.

Bone Tumor Environment as a Potential Therapeutic Target in Ewing Sarcoma

PubMed Central

Redini, Françoise; Heymann, Dominique

2015-01-01

Ewing sarcoma is the second most common pediatric bone tumor, with three cases per million worldwide. In clinical terms, Ewing sarcoma is an aggressive, rapidly fatal malignancy that mainly develops not only in osseous sites (85%) but also in extra-skeletal soft tissue. It spreads naturally to the lungs, bones, and bone marrow with poor prognosis in the two latter cases. Bone lesions from primary or secondary (metastases) tumors are characterized by extensive bone remodeling, more often due to osteolysis. Osteoclast activation and subsequent bone resorption are responsible for the clinical features of bone tumors, including pain, vertebral collapse, and spinal cord compression. Based on the “vicious cycle” concept of tumor cells and bone resorbing cells, drugs, which target osteoclasts, may be promising agents as adjuvant setting for treating bone tumors, including Ewing sarcoma. There is also increasing evidence that cellular and molecular protagonists present in the bone microenvironment play a part in establishing a favorable “niche” for tumor initiation and progression. The purpose of this review is to discuss the potential therapeutic value of drugs targeting the bone tumor microenvironment in Ewing sarcoma. The first part of the review will focus on targeting the bone resorbing function of osteoclasts by means of bisphosphonates or drugs blocking the pro-resorbing cytokine receptor activator of NF-kappa B ligand. Second, the role of this peculiar hypoxic microenvironment will be discussed in the context of resistance to chemotherapy, escape from the immune system, or neo-angiogenesis. Therapeutic interventions based on these specificities could be then proposed in the context of Ewing sarcoma. PMID:26779435

Bone Tumor Environment as a Potential Therapeutic Target in Ewing Sarcoma.

PubMed

Redini, Françoise; Heymann, Dominique

2015-01-01

Ewing sarcoma is the second most common pediatric bone tumor, with three cases per million worldwide. In clinical terms, Ewing sarcoma is an aggressive, rapidly fatal malignancy that mainly develops not only in osseous sites (85%) but also in extra-skeletal soft tissue. It spreads naturally to the lungs, bones, and bone marrow with poor prognosis in the two latter cases. Bone lesions from primary or secondary (metastases) tumors are characterized by extensive bone remodeling, more often due to osteolysis. Osteoclast activation and subsequent bone resorption are responsible for the clinical features of bone tumors, including pain, vertebral collapse, and spinal cord compression. Based on the "vicious cycle" concept of tumor cells and bone resorbing cells, drugs, which target osteoclasts, may be promising agents as adjuvant setting for treating bone tumors, including Ewing sarcoma. There is also increasing evidence that cellular and molecular protagonists present in the bone microenvironment play a part in establishing a favorable "niche" for tumor initiation and progression. The purpose of this review is to discuss the potential therapeutic value of drugs targeting the bone tumor microenvironment in Ewing sarcoma. The first part of the review will focus on targeting the bone resorbing function of osteoclasts by means of bisphosphonates or drugs blocking the pro-resorbing cytokine receptor activator of NF-kappa B ligand. Second, the role of this peculiar hypoxic microenvironment will be discussed in the context of resistance to chemotherapy, escape from the immune system, or neo-angiogenesis. Therapeutic interventions based on these specificities could be then proposed in the context of Ewing sarcoma.

Effect of component compression on the initial performance of an IPV nickel-hydrogen cell

NASA Technical Reports Server (NTRS)

Gahn, Randall F.

1987-01-01

An experimental method was developed for evaluating the effect of component compression on the charge and discharge voltage characteristics of a 3 1/2 in. diameter boiler plate cell. A standard boiler plate pressure vessel was modified by the addition of a mechanical feedthrough on the bottom of the vessel which permitted different compressions to be applied to the components without disturbing the integrity of the stack. Compression loadings from 0.94 to 27.4 psi were applied by suspending weights from the feedthrough rod. Cell voltages were measured for 0.96-C, 55-min charge and for 1.37-C, 35-min and 2-C, 24-min discharges. An initial change in voltage performance on both charge and discharge as the loading increased was attributed to seating of the components. Subsequent variation of the compression from 2.97 to 27.4 psi caused only minor changes in either the charge or the discharge voltages. Several one month open-circuit voltage stands and 1100 cycles under LEO conditions at the maximum loading have produced no change in performance.

Effect of component compression on the initial performance of an IPV nickel-hydrogen cell. [Individual Pressure Vessel

NASA Technical Reports Server (NTRS)

Gahn, Randall F.

1987-01-01

An experimental method was developed for evaluating the effect of component compression on the charge and discharge voltage characteristics of a 3 1/2 in. diameter boiler plate cell. A standard boiler plate pressure vessel was modified by the addition of a mechanical feedthrough on the bottom of the vessel which permitted different compressions to be applied to the components without disturbing the integrity of the stack. Compression loadings from 0.94 to 27.4 psi were applied by suspending weights from the feedthrough rod. Cell voltages were measured for 0.96-C, 55-min charge and for 1.37-C, 35-min and 2-C, 24-min discharges. An initial change in voltage performance on both charge and discharge as the loading increased was attributed to seating of the components. Subsequent variation of the compression from 2.97 to 27.4 psi caused only minor changes in either the charge or the discharge voltages. Several one month open-circuit voltage stands and 1100 cycles under LEO conditions at the maximum loading have produced no change in performance.

Optimal Surgical Therapy in a Porcine (Sus scrofa) Model of Extra-Thoracic Penetrating Trauma Resulting in Hemorrhagic Shock: ED Thoracotomy vs. Immediate Trans-Abdominal Vascular Control. A Porcine Model for Evaluating the Management of Non-Compressible Torso Hemorrhage

DTIC Science & Technology

2010-11-08

celiac aortic clamping (n=6), direct vascular control (n=6), and endovascular aortic occlusion n=6). This study presents a large animal model of class...including thoracic aortic clamping, supra- celiac aortic clamping, direct vascular control, and proximal endovascular balloon occlusion. Following vascular...subsequently underwent non-compressible hemorrhage with thoracic aortic clamping (n=6), supra- celiac aortic clamping (n=6), direct vascular control (n=6

Clinical outcomes of vertebroplasty or kyphoplasty for patients with vertebral compression fractures: a nationwide cohort study.

PubMed

Tsai, Yi-Wen; Hsiao, Fei-Yuan; Wen, Yu-Wen; Kao, Yu-Hsiang; Chang, Li-Chuan; Huang, Weng-Foung; Peng, Li-Ning; Liu, Chien-Liang; Chen, Liang-Kung

2013-01-01

To evaluate the outcome of vertebroplasty or kyphoplasty (VK), in comparison with non-VK treatment, among patients hospitalized for first-ever vertebral compression fractures (VCFs). A population-based retrospective cohort study. Taiwan' s National Health Insurance claims data. All individuals aged ≥ 60 years who were newly discharged after hospitalization for a primary VCF diagnosis. Percutaneous vertebroplasty or kyphoplasty. Study outcomes were discharge outcome (re-hospitalization within 1 week, 1 month or 6 months, categorized by diagnosis) and the prescription of anti-osteoporosis medication for secondary fracture prevention. Potential selection bias was adjusted by using propensity score matching to select one conservatively treated patient (e.g. lumbar brace, analgesics, or physical therapy) matched to one patient receiving VK. The study cohort consisted of 9238 patients who had been discharged after hospitalization for a first-ever VCF between 2004 and 2007. During the index hospitalization, 1018 patients received VK, compared with 8,220 patients who did not receive VK. Patients receiving percutaneous procedure group had a consistently lower incidence of 7-day re-hospitalization for any of the three outcomes (OR = 0.48; 95% CI: 0.32-0.72). Considering the cause of re-hospitalization separately, the vertebroplasty/kyphoplasty group had a significantly lower risk of 7-day re-hospitalization for fracture-related diagnosis (OR = 0.28, 95% CI: 0.12-0.68) and musculoskeletal diagnosis (OR = 0.08, 95% CI: 0.01-0.88) as well as a significantly lower risk of 1-month re-hospitalization (OR = 0.74; 95% CI: 0.59-0.93). VK may protect patients with VCFs from short-term re-hospitalization and a greater need exists for anti-osteoporosis medication as secondary prevention for this at-risk patient group. Copyright © 2013 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

Cost-effectiveness analysis of treatments for vertebral compression fractures.

PubMed

Edidin, Avram A; Ong, Kevin L; Lau, Edmund; Schmier, Jordana K; Kemner, Jason E; Kurtz, Steven M

2012-07-01

Vertebral compression fractures (VCFs) can be treated by nonsurgical management or by minimally invasive surgical treatment including vertebroplasty and balloon kyphoplasty. The purpose of the present study was to characterize the cost to Medicare for treating VCF-diagnosed patients by nonsurgical management, vertebroplasty, or kyphoplasty. We hypothesized that surgical treatments for VCFs using vertebroplasty or kyphoplasty would be a cost-effective alternative to nonsurgical management for the Medicare patient population. Cost per life-year gained for VCF patients in the US Medicare population was compared between operated (kyphoplasty and vertebroplasty) and non-operated patients and between kyphoplasty and vertebroplasty patients, all as a function of patient age and gender. Life expectancy was estimated using a parametric Weibull survival model (adjusted for comorbidities) for 858 978 VCF patients in the 100% Medicare dataset (2005-2008). Median payer costs were identified for each treatment group for up to 3 years following VCF diagnosis, based on 67 018 VCF patients in the 5% Medicare dataset (2005-2008). A discount rate of 3% was used for the base case in the cost-effectiveness analysis, with 0% and 5% discount rates used in sensitivity analyses. After accounting for the differences in median costs and using a discount rate of 3%, the cost per life-year gained for kyphoplasty and vertebroplasty patients ranged from $US1863 to $US6687 and from $US2452 to $US13 543, respectively, compared with non-operated patients. The cost per life-year gained for kyphoplasty compared with vertebroplasty ranged from -$US4878 (cost saving) to $US2763. Among patients for whom surgical treatment was indicated, kyphoplasty was found to be cost effective, and perhaps even cost saving, compared with vertebroplasty. Even for the oldest patients (85 years of age and older), both interventions would be considered cost effective in terms of cost per life-year gained.

Item response theory analysis to evaluate reliability and minimal clinically important change of the Roland-Morris Disability Questionnaire in patients with severe disability due to back pain from vertebral compression fractures.

PubMed

Lee, Minji K; Yost, Kathleen J; McDonald, Jennifer S; Dougherty, Ryne W; Vine, Roanna L; Kallmes, David F

2017-06-01

The majority of validation done on the Roland-Morris Disability Questionnaire (RMDQ) has been in patients with mild or moderate disability. There is paucity of research focusing on the psychometric quality of the RMDQ in patients with severe disability. To evaluate the psychometric quality of the RMDQ in patients with severe disability. Observational clinical study. The sample consisted of 214 patients with painful vertebral compression fractures who underwent vertebroplasty or kyphoplasty. The 23-item version of the RMDQ was completed at two time points: baseline and 30-day postintervention follow-up. With the two-parameter logistic unidimensional item response theory (IRT) analyses, we derived the range of scores that produced reliable measurement and investigated the minimal clinically important difference (MCID). Scores for 214 (100%) patients at baseline and 108 (50%) patients at follow-up did not meet the reliability criterion of 0.90 or higher, with the majority of patients having disability due to back pain that was too severe to be reliably measured by the RMDQ. Depending on methodology, MCID estimates ranged from 2 to 8 points and the proportion of patients classified as having experienced meaningful improvement ranged from 26% to 68%. A greater change in score was needed at the extreme ends of the score scale to be classified as having achieved MCID using IRT methods. Replacing items measuring moderate disability with items measuring severe disability could yield a version of the RMDQ that better targets patients with severe disability due to back pain. Improved precision in measuring disability would be valuable to clinicians who treat patients with greater functional impairments. Caution is needed when choosing criteria for interpreting meaningful change using the RMDQ. Copyright © 2017 Elsevier Inc. All rights reserved.

A new method to include the gravitational forces in a finite element model of the scoliotic spine.

PubMed

Clin, Julien; Aubin, Carl-Éric; Lalonde, Nadine; Parent, Stefan; Labelle, Hubert

2011-08-01

The distribution of stresses in the scoliotic spine is still not well known despite its biomechanical importance in the pathomechanisms and treatment of scoliosis. Gravitational forces are one of the sources of these stresses. Existing finite element models (FEMs), when considering gravity, applied these forces on a geometry acquired from radiographs while the patient was already subjected to gravity, which resulted in a deformed spine different from the actual one. A new method to include gravitational forces on a scoliotic trunk FEM and compute the stresses in the spine was consequently developed. The 3D geometry of three scoliotic patients was acquired using a multi-view X-ray 3D reconstruction technique and surface topography. The FEM of the patients' trunk was created using this geometry. A simulation process was developed to apply the gravitational forces at the centers of gravity of each vertebra level. First the "zero-gravity" geometry was determined by applying adequate upwards forces on the initial geometry. The stresses were reset to zero and then the gravity forces were applied to compute the geometry of the spine subjected to gravity. An optimization process was necessary to find the appropriate zero-gravity and gravity geometries. The design variables were the forces applied on the model to find the zero-gravity geometry. After optimization the difference between the vertebral positions acquired from radiographs and the vertebral positions simulated with the model was inferior to 3 mm. The forces and compressive stresses in the scoliotic spine were then computed. There was an asymmetrical load in the coronal plane, particularly, at the apices of the scoliotic curves. Difference of mean compressive stresses between concavity and convexity of the scoliotic curves ranged between 0.1 and 0.2 MPa. In conclusion, a realistic way of integrating gravity in a scoliotic trunk FEM was developed and stresses due to gravity were explicitly computed. This is a valuable improvement for further biomechanical modeling studies of scoliosis.

The Biomechanical Properties of Pedicle Screw Fixation Combined With Trajectory Bone Cement Augmentation in Osteoporotic Vertebrae.

PubMed

Fan, Haitao T; Zhang, Renjie J; Shen, Cailiang L; Dong, Fulong L; Li, Yong; Song, Peiwen W; Gong, Chen; Wang, Yijin J

2016-03-01

The biomechanics of pedicle screw fixation combined with trajectory cement augmentation with various filling volumes were measured by pull-out, periodic antibending, and compression fatigue tests. To investigate the biomechanical properties of the pedicle screw fixation combined with trajectory bone cement (polymethylmethacrylate) augmentation in osteoporotic vertebrae and to explore the optimum filling volume of the bone cement. Pedicle screw fixation is considered to be the most effective posterior fixation method. The decrease of the bone mineral density apparently increases the fixation failure risk caused by screw loosening and displacement. Trajectory bone cement augmentation has been confirmed to be an effective method to increase the bone intensity and could markedly increase the stability of the fixation interface. Sixteen elderly cadaveric 1-5 lumbar vertebral specimens were diagnosed with osteoporosis. The left and right vertebral pedicles were alternatively randomized for treatment in all groups, with the contralateral pedicles as control. The study groups included: group A (pedicle screw fixation with full trajectory bone cement augmentation), group B (75% filling), group C (50% filling), and group D (25% filling). Finally, the bone cement leakage and dispersion were assessed and the mechanical testing was conducted. The bone cement was well dispersed around the pedicle screw. The augmented bone intensity, pull-out strength, periodic loading times, and compression fatigue performance were markedly higher than those of the control groups. With the increase in trajectory bone cement, the leakage was also increased (P<0.05). The pull-out strength of the pedicle screw was increased with an increase in bone mineral density and trajectory bone cement. It peaked at 75% filling, with the largest power consumption. The optimal filling volume of the bone cement was 75% of the trajectory volume (about 1.03 mL). The use of excessive bone cement did not increase the fixation intensity but increased the risk of leakage.

The floor plate is sufficient for development of the sclerotome and spine without the notochord.

PubMed

Ando, Takashi; Semba, Kei; Suda, Hiroko; Sei, Akira; Mizuta, Hiroshi; Araki, Masatake; Abe, Kuniya; Imai, Kenji; Nakagata, Naomi; Araki, Kimi; Yamamura, Ken-ichi

2011-01-01

Danforth'sshort-tail (Sd) mouse is a semi-dominant mutation affecting the development of the vertebral column. Although the notochord degenerates completely by embryonic day 9.5, the vertebral column exists up to the lumber region, suggesting that the floor plate can substitute for notochord function. We previously established the mutant mouse line, Skt(Gt), through gene trap mutagenesis and identified the novel gene, Skt, which was mapped 0.95cM distal to the Sd locus. Taking advantage of the fact that monitoring notochordal development and genotyping of the Sd locus can be performed using the Skt(Gt) allele, we assessed the development of the vertebra, notochord, somite, floor plate and sclerotome in +-+/+-Skt(Gt), Sd-+/+-+, Sd-Skt(Gt)/+-+, Sd-Skt(Gt)/+-Skt(Gt), Sd-+/Sd-+ and Sd-Skt(Gt)/Sd-Skt(Gt) embryos. In Sd homozygous mutants with a C57BL/6 genetic background, the vertebral column was truncated in the 6th thoracic vertebra, which was more severe than previously reported. The floor plate and sclerotome developed to the level of somite before notochord degeneration and the number of remaining vertebrae corresponded well with the level of development of the floor plate and sclerotome. Defects to the sclerotome and subsequent vertebral development were not due to failure of somitogenesis. Taken together, these results suggest that the notochord induced floor plate development before degeneration, and that the remaining floor plate is sufficient for maintenance of differentiation of the somite into the sclerotome and vertebra in the absence of the notochord. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Evolutionary history of the enolase gene family.

PubMed

Tracy, M R; Hedges, S B

2000-12-23

The enzyme enolase [EC 4.2.1.11] is found in all organisms, with vertebrates exhibiting tissue-specific isozymes encoded by three genes: alpha (alpha), beta (beta), and gamma (gamma) enolase. Limited taxonomic sampling of enolase has obscured the timing of gene duplication events. To help clarify the evolutionary history of the gene family, cDNAs were sequenced from six taxa representing major lineages of vertebrates: Chiloscyllium punctatum (shark), Amia calva (bowfin), Salmo trutta (trout), Latimeria chalumnae (coelacanth), Lepidosiren paradoxa (South American lungfish), and Neoceratodus forsteri (Australian lungfish). Phylogenetic analysis of all enolase and related gene sequences revealed an early gene duplication event prior to the last common ancestor of living organisms. Several distantly related archaebacterial sequences were designated as 'enolase-2', whereas all other enolase sequences were designated 'enolase-1'. Two of the three isozymes of enolase-1, alpha- and beta-enolase, were discovered in actinopterygian, sarcopterygian, and chondrichthian fishes. Phylogenetic analysis of vertebrate enolases revealed that the two gene duplications leading to the three isozymes of enolase-1 occurred subsequent to the divergence of living agnathans, near the Proterozoic/Phanerozoic boundary (approximately 550Mya). Two copies of enolase, designated alpha(1) and alpha(2), were found in the trout and are presumed to be the result of a genome duplication event.

Expression patterns of sex differentiation-related genes during gonadal sex change in the protogynous wrasse, Halichoeres trimaculatus.

PubMed

Horiguchi, Ryo; Nozu, Ryo; Hirai, Toshiaki; Kobayashi, Yasuhisa; Nakamura, Masaru

2018-02-01

The three-spot wrasse, Halichoeres trimaculatus, can change sex from female to male (i.e. protogyny) due to sharp decrease in endogenous estrogen. During the sex change, ovarian tissue degenerates and testicular tissue arises newly. Finally, ovarian tissue disappears completely and replaces into mature testis. In order to predict the molecular mechanisms controlling the processes of sex change, we investigated the expression patterns of four genes (rspo1, figla, sox9b and amh), which have been thought to be associated with ovarian/testicular differentiation in vertebrates. Expression levels of rspo1 and figla, which play important roles for ovarian differentiation in vertebrates, were stable until the middle stage of the sex change, and subsequently down-regulated. Therefore, it was indicated that decrease in rspo1 and figla could result from ovarian degeneration. On the other hand, basis on the expression pattern, it was indicated that sox9b and amh, which are involved in testicular differentiation in vertebrates, were implicated in testicular formation and spermatogenesis during the sex change as well. The present results could be fundamental information for investigating the relationship between these factors and E2 depletion, which is crucial trigger for sex change. Copyright © 2017 Elsevier Inc. All rights reserved.

Stress and aversive learning in a wild vertebrate: the role of corticosterone in mediating escape from a novel stressor.

PubMed

Thaker, Maria; Vanak, Abi T; Lima, Steven L; Hews, Diana K

2010-01-01

Elevated plasma corticosterone during stressful events is linked to rapid changes in behavior in vertebrates and can mediate learning and memory consolidation. We tested the importance of acute corticosterone elevation in aversive learning of a novel stressor by wild male eastern fence lizards (Sceloporus undulatus). We found that inhibiting corticosterone elevation (using metyrapone, a corticosterone synthesis blocker) during an encounter with a novel attacker impaired immediate escape responses and limited learning and recall during future encounters. In the wild and in outdoor enclosures, lizards whose acute corticosterone response was blocked by an earlier metyrapone injection did not alter their escape behavior during repeated encounters with the attacker. Control-injected (unblocked) lizards, however, progressively increased flight initiation distance and decreased hiding duration during subsequent encounters. Aversive responses were also initially higher for control lizards exposed to a higher intensity first attack. Further, we demonstrate a role of corticosterone elevation in recollection, since unblocked lizards had heightened antipredator responses 24-28 h later. Exogenously restoring corticosterone levels in metyrapone-injected lizards maintained aversive behaviors and learning at control (unblocked) levels. We suggest that the corticosterone mediation of antipredator behaviors and aversive learning is a critical and general mechanism for the behavioral flexibility of vertebrate prey.

Symposium on the evolution and development of the vertebrate head.

PubMed

Depew, Michael J; Olsson, Lennart

2008-06-15

Among the symposia held at the seminal meeting of the European Society for Evolutionary Developmental Biology was one centered on the development and evolution of the vertebrate head, an exquisitely complex anatomical system. The articles presented at this meeting have been gathered in a special issue of the Journal of Experimental Zoology, and are here reviewed by the organizers of the symposia. These articles cover a breadth of subjects, including interactions between cells derived from the different germ layers, such as those underlying neural crest cell migration and fate and cranial muscle specification, as well as placode development and the origin, development, and evolution of important evolutionary innovations such as jaws and the trabecula cranii. In this introduction, we provide a short historical overview of themes of research into the fundamental organization, structure, and development of the vertebrate head, including the search for head segmentation and the relevance of the New Head Hypothesis, and subsequently present the topics discussed in each of the articles. This overview of the past and the present of head evo-devo is then followed by a glimpse at its possible future and a brief examination of the utility of the notions of heterochrony, heterotopy, and heterofacience in describing evolutionarily important changes in developmental events. (c) 2008 Wiley-Liss, Inc.

Mechanisms of Oxidative Stress Resistance in The Brain: Lessons Learned From Hypoxia Tolerant Extremophilic Vertebrates

PubMed Central

Garbarino, Valentina R.; Orr, Miranda E.; Rodriguez, Karl A.; Buffenstein, Rochelle

2016-01-01

The Oxidative Stress Theory of Aging has had tremendous impact in research involving aging and age-associated diseases including those that affect the nervous system. With over half a century of accrued data showing both strong support for and against this theory, there is a need to critically evaluate the data acquired from common biomedical research models, and to also diversify the species used in studies involving this proximate theory. One approach is to follow Orgel’s second axiom that “evolution is smarter than we are” and judiciously choose species that may have evolved to live with chronic or seasonal oxidative stressors. Vertebrates that have naturally evolved to live under extreme conditions (e.g., anoxia or hypoxia), as well as those that undergo daily or seasonal torpor encounter both decreased oxygen availability and subsequent reoxygenation, with concomitant increased oxidative stress. Due to its high metabolic activity, the brain may be particularly vulnerable to oxidative stress. Here, we focus on oxidative stress responses in the brains of certain mouse models as well as extremophilic vertebrates. Exploring the naturally evolved biological tools utilized to cope with seasonal or environmentally variable oxygen availability may yield key information pertinent for how to deal with oxidative stress and thereby mitigate its propagation of age-associated diseases. PMID:25841340

Permo-Triassic vertebrate extinctions: A program

NASA Technical Reports Server (NTRS)

Olson, E. C.

1988-01-01

Since the time of the Authors' study on this subject, a great deal of new information has become available. Concepts of the nature of extinctions have changed materially. The Authors' conclusion that a catastrophic event was not responsible for the extinction of vertebrates has modified to the extent that hypotheses involving either the impact of a massive extra-terrestrial body or volcanism provide plausible but not currently fully testable hypotheses. Stated changes resulted in a rapid decrease in organic diversity, as the ratio of origins of taxa to extinctions shifted from strongly positive to negative, with momentary equilibrium being reached at about the Permo-Triassic boundary. The proximate causes of the changes in the terrestrial biota appear to lie in two primary factors: (1) strong climatic changes (global mean temperatures, temperature ranges, humidity) and (2) susceptibility of the dominant vertebrates (large dicynodonts) and the glossopteris flora to disruption of the equlibrium of the world ecosystem. The following proximate causes have been proposed: (1) rhythmic fluctuations in solar radiation, (2) tectonic events as Pangea assembled, altering land-ocean relationships, patterns of wind and water circulation and continental physiography, (3) volcanism, and (4) changes subsequent to impacts of one or more massive extra terrestrial objects, bodies or comets. These hypotheses are discussed.

Uneventful upper cervical manipulation in the presence of a damaged vertebral artery.

PubMed

Michaud, Thomas C

2002-09-01

To discuss a case in which a patient with a previously injured vertebral artery underwent manipulation in the upper cervical spine without alteration of her symptom pattern. The literature concerning the relative safety of specific upper cervical manipulative techniques is reviewed. A 42-year-old woman had a 3-week history of unilateral suboccipital pain that she related to a sudden twisting of her head and neck that occurred while she was putting sheets of drywall on top of her car. Subsequent examination by a neurologist 2 weeks later was unremarkable, and a tension-type headache was diagnosed. Approximately 10 days later (3 weeks after injury), a single high-velocity upper-cervical manipulation (incorporating slight rotation and full lateral flexion) was performed with no change in her symptom pattern. Two weeks after that, the patient had development of a lateral medullary syndrome (also known as Wallenberg syndrome) after she briefly extended and rotated her upper cervical spine while painting a ceiling. The patient was treated with anticoagulant therapy, and the lateral medullary infarct healed without incident. The spinocerebellar and subtle motor symptoms also resolved, but the ipsilateral suboccipital headache and the loss of temperature sensation associated with the spinothalamic tract lesion were still present 9 months later. This case report demonstrates that vigorous manipulation of the upper cervical spine is possible without injuring an already damaged vertebral artery. It is suggested that the line of drive used during the single manipulation, almost pure lateral flexion with slight rotation, was responsible for the apparent innocuous response. Guidelines for the evaluation and management of vertebral artery dissection are reviewed. Because it is currently impossible to identify patients at risk of having a dissected vertebral artery with standard in-office examination procedures, rotational manipulation of the upper cervical spine should be abandoned by all practitioners, and schools should remove such techniques from their curriculums.

A primary phosphorus-deficient skeletal phenotype in juvenile Atlantic salmon Salmo salar: the uncoupling of bone formation and mineralization.

PubMed

Witten, P E; Owen, M A G; Fontanillas, R; Soenens, M; McGurk, C; Obach, A

2016-02-01

To understand the effect of low dietary phosphorus (P) intake on the vertebral column of Atlantic salmon Salmo salar, a primary P deficiency was induced in post-smolts. The dietary P provision was reduced by 50% for a period of 10 weeks under controlled conditions. The animal's skeleton was subsequently analysed by radiology, histological examination, histochemical detection of minerals in bones and scales and chemical mineral analysis. This is the first account of how a primary P deficiency affects the skeleton in S. salar at the cellular and at the micro-anatomical level. Animals that received the P-deficient diet displayed known signs of P deficiency including reduced growth and soft, pliable opercula. Bone and scale mineral content decreased by c. 50%. On radiographs, vertebral bodies appear small, undersized and with enlarged intervertebral spaces. Contrary to the X-ray-based diagnosis, the histological examination revealed that vertebral bodies had a regular size and regular internal bone structures; intervertebral spaces were not enlarged. Bone matrix formation was continuous and uninterrupted, albeit without traces of mineralization. Likewise, scale growth continues with regular annuli formation, but new scale matrix remains without minerals. The 10 week long experiment generated a homogeneous osteomalacia of vertebral bodies without apparent induction of skeletal malformations. The experiment shows that bone formation and bone mineralization are, to a large degree, independent processes in the fish examined. Therefore, a deficit in mineralization must not be the only cause of the alterations of the vertebral bone structure observed in farmed S. salar. It is discussed how the observed uncoupling of bone formation and mineralization helps to better diagnose, understand and prevent P deficiency-related malformations in farmed S. salar. © 2015 The Authors.Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.

Naturally occurring secondary nutritional hyperparathyroidism in cattle egrets (Bubulcus ibis) from central Texas.

PubMed

Phalen, David N; Drew, Mark L; Contreras, Cindy; Roset, Kimberly; Mora, Miguel

2005-04-01

Naturally occurring secondary nutritional hyperparathyroidism is described in the nestlings of two colonies of cattle egrets (Bubulcus ibis) from Central Texas (Bryan and San Antonio, Texas, USA). Nestlings from a third colony (Waco, Texas, USA) were collected in a subsequent year for comparison. Birds from the first two colonies consistently had severe osteopenia and associated curving deformities and folding fractures of their long bones. These birds also had reduced bone ash, increased osteoclasia, a marked decrease in osteoblast activity, variable lengthening and shortening of the hypertrophic zone of the epiphyseal cartilage, decreased and disorganized formation of new bone, and a marked hypertrophy and hyperplasia of the parathyroid glands as compared to birds collected from the third colony. Fibrous osteodystrophy was found in all of the birds from San Antonio and Bryan. Evidence of moderate to severe calcium deficiency was also identified in 33% of the cattle egrets collected from Waco. Gut contents of affected chicks contained predominately grasshoppers and crickets; vertebrate prey items were absent from the Bryan birds. Grasshoppers and crickets collected from fields frequented by the adult egrets in 1994 had 0.12-0.28% calcium and 0.76-0.81% phosphorus. Pooled grasshoppers and crickets collected during a subsequent wet early spring averaged 0.24% calcium and 0.65% phosphorus. Although the phosphorus content of the insect prey was adequate for growth, calcium was approximately one-third the minimum calcium requirement needed for growth for other species of birds. It was postulated that cattle egrets breeding in Central Texas have expanded their range into habitat that contains less vertebrate prey, and as a result, many nestling egrets are being fed diets that contain suboptimal calcium. Therefore, in years where vertebrate prey is scarce and forage for insect prey is reduced in calcium, nestling egrets are at risk for developing secondary nutritional hyperparathyroidism.