bluuebunny/crossref_metadata_2025 huggingface dataset:
Traumatic burst fracture in a patient with a lumbar artificial disc
Authors: Gottfried Oren N. , Brodke Darrel S.
Published: February 2011

Lumbar disc arthroplasty is now a common treatment for lumbar degenerative disc disease. Whereas the immediate and delayed complications in patients with artificial lumbar discs are well reported, the durability of artificial disc hardware after severe spine trauma is unknown. The authors describe the management of a rare case of a traumatic lumbar burst fracture in a patient who had undergone disc arthroplasty. This 31-year-old male contractor had undergone placement of an L4–5 Charité artificial disc (DePuy Spine) and L5–S1 anterior lumbar fusion 10 months before he fell from a roof and sustained a traumatic L-3 burst fracture with significant canal compromise and cauda equina injury. Despite the considerable compressive load on his spine, the artificial disc (L4–5) remained intact without any radiological signs of hardware failure, and the vertebrae above (L-4) and below (L-5) the artificial disc had no signs of injury. For the L-3 burst fracture the patient underwent an open decompressive laminectomy at L2–3 and posterior fusion with instrumentation from L-2 to L-4. At 24 months postinjury, he had returned to full work activities as a contractor with minimal back pain and mild right lower-extremity sensory changes and weakness left over from the trauma. The total disc arthroplasty at L4–5 is functional and has preserved motion, and there is a solid fusion at L2–4 and L5–S1. This case demonstrates that a lumbar artificial disc can tolerate a significant load from trauma and remain functional without hardware failure even after a traumatic burst fracture at the adjacent lumbar vertebral body and shows the successful treatment of this fracture, with posterior fusion preserving the motion of an artificial disc.
Cervical spine dural arteriovenous fistula presenting with congestive myelopathy of the conus
Authors: Geibprasert Sasikhan , Pongpech Sirintara , Jiarakongmun Pakorn , Krings Timo
Published: February 2011

Spinal dural arteriovenous fistulas (DAVFs) are the spinal vascular malformations that are encountered most often, and they are usually encountered in the lower thoracic region. Cervical spine DAVFs are exceedingly rare and may be difficult to differentiate from radicular arteriovenous malformations, epidural arteriovenous shunts, or perimedullary AVFs. Typical angiographic findings in spinal DAVFs include a slow-flow shunt with converging feeding vessels from radiculomeningeal arteries draining via a radicular vein centripetally into perimedullary veins. The MR imaging findings such as spinal cord edema and perimedullary dilated vessels may be used to direct the spinal angiography that is needed to localize and classify the shunt. When the shunt is distant from the pathological imaging findings, the diagnosis may be difficult to establish, especially when the shunt is present at an atypical location such as the cervical spine. The authors present the case of a 51-year-old man presenting with lower thoracic and conus medullaris congestive edema due to a cervical spine DAVF that was located at the C-5 level. Transarterial embolization with N-butyl cyanoacrylate closed the proximal vein and completely obliterated the fistula. Clinical and imaging follow-up confirmed occlusion of the fistula, with improvement in clinical symptoms.
Clinical results of cervical myelopathy in patients older than 80 years of age: evaluation of spinal function with motor evoked potentials
Authors: Tanaka Nobuhiro , Nakanishi Kazuyoshi , Fujimoto Yoshinori , Sasaki Hirofumi , Kamei Naosuke , Hamasaki Takahiko , Yamada Kiyotaka , Yamamoto Risako , Nakamae Toshio , Ochi Mitsuo
Published: February 2011

Object

In this prospective analysis the authors describe the clinical results of surgical treatment in patients > 80 years of age in whom spinal function was evaluated with motor evoked potential (MEPs) monitoring.

Methods

The authors included 57 patients > 80 years of age who were suspected of having cervical myelopathy. The mean age of the patients was 83.0 years (range 80–90 years). The central motor conduction time (CMCT) was calculated from the latencies of the MEPs following transcranial magnetic stimulation and from M and F waves following peripheral nerve stimulation.

Results

Preoperative electrophysiological evaluation demonstrated significant elongation of CMCT or abnormalities in MEP waveforms in 37 patients (65%), and 35 patients of these underwent laminoplasty. In 30 patients cervical spondylotic myelopathy was diagnosed and 5 patients ossification of the posterior longitudinal ligament was diagnosed. The preoperative mean Japanese Orthopaedic Association Scale score was 8.6 (range 3–12.5) and the mean postoperative score was 12.6 (range 6–14.5) with an average recovery rate of 45% (range −21 to 100%). There were no major complications in any of the patients during the operative period and there were no cases of death resulting from operative intervention.

Conclusions

Sufficient clinical results are expected even in patients with myelopathy who are older than 80 years of age, provided the patients are correctly selected by electrophysiological evaluation with MEPs and CMCT.
The quality of quality of life publications in the spinal literature: are we getting any better?
Authors: Street John , Lenehan Brian , Fisher Charles
Published: February 2011

Object

Criteria for methodological quality have been widely accepted in many fields of surgical practice. These criteria include those of Velanovich and Gill and Feinstein. No such analysis of the spine surgery literature has ever been reported. This study is a systematic review of the quality of life (QOL) publications to determine if the recent interest in QOL measurements following spinal surgery has been accompanied by an improvement in the quality of the papers published.

Methods

The archives of the journals Journal of Neurosurgery: Spine, Spine, Journal of Spinal Disorders & Techniques, European Spine Journal, and The Spine Journal, for the years 2000–2004 inclusive, were examined, and all publications reporting QOL outcomes were analyzed. Each paper was scored according to the criteria of Velanovich and Gill and Feinstein, and the methodological quality of these manuscripts—and any time-dependent changes—were determined.

Results

During the study period, the total number of articles published increased by 36%, while the number of QOL articles increased by 102%. According to the criteria of Velanovich, there was a statistically significant improvement in the quality of the publications over the study period (p = 0.0394). In 2000, only 27% of outcome measures were disease specific, 77% were valid, and 77% were appropriate for the study design. In 2004, 43% were disease specific, 88% were valid, and 89% were appropriate. In 2000, 53% of studies used appropriate statistical analysis compared with 100 and 96% for 2003 and 2004, respectively. There was no demonstrable improvement in the fulfillment of the more rigorous Gill and Feinstein criteria for any of the 5 journals over the period of the study.

Conclusions

The authors' study illustrates a moderate improvement in the quality of these publications over the study period but much methodological improvement is required.
Positional vertebral artery compression and vertebrobasilar insufficiency due to a herniated cervical disc
Authors: Ujifuku Kenta , Hayashi Kentaro , Tsunoda Keishi , Kitagawa Naoki , Hayashi Tomayoshi , Suyama Kazuhiko , Nagata Izumi
Published: February 2011

The authors report a case of vertebrobasilar insufficiency caused by vertebral artery (VA) compression due to a herniated cervical disc, which was surgically treated with the aid of intraoperative angiography. This 78-year-old man visited the hospital because of syncope following head rotation. Admission CT scans revealed a calcified mass adjacent to the right lateral process of the C-4 spine. Cervical angiography demonstrated an obstruction of the right VA at this region on rotation of the head to the right. The operation revealed a cervical disc protruding toward the right VA. The disc was surgically removed, and then the decompression of the right VA was confirmed on intraoperative angiography studies. A histopathological examination showed fibrohyaline cartilage, indicating an ossified intervertebral disc. The postoperative course was uneventful, and he has not experienced any syncope since treatment. A cervical disc herniation could be a cause of vertebrobasilar insufficiency by exerting positional compression of the VA. Intraoperative angiography could be quite useful to confirm this condition during decompression surgery for a cervical VA.
Image classification of idiopathic spinal cord herniation based on symptom severity and surgical outcome: a multicenter study
Authors: Imagama Shiro , Matsuyama Yukihiro , Sakai Yoshihito , Nakamura Hiroshi , Katayama Yoshito , Ito Zenya , Wakao Norimitsu , Sato Koji , Kamiya Mitsuhiro , Kato Fumihiko , Yukawa Yasutsugu , Miura Yasushi , Yoshihara Hisatake , Suzuki Kazuhiro , Ando Kei , Hirano Kenichi , Tauchi Ryoji , Muramoto Akio , Ishiguro Naoki
Published: February 2011

Object

The purpose of this study was to provide the first evidence for image classification of idiopathic spinal cord herniation (ISCH) in a multicenter study.

Methods

Twelve patients who underwent surgery for ISCH were identified, and preoperative symptoms, severity of paralysis and myelopathy, disease duration, plain radiographs, MR imaging and CT myelography findings, surgical procedure, intraoperative findings, data from spinal cord monitoring, and postoperative recovery were investigated in these patients. Findings on sagittal MR imaging and CT myelography were classified into 3 types: a kink type (Type K), a discontinuous type (Type D), and a protrusion type (Type P). Using axial images, the location of the hiatus was classified as either central (Type C) or lateral (Type L), and the laterality of the herniated spinal cord was classified based on correspondence (same; Type S) or noncorrespondence (opposite; Type O) with the hiatus location. A bone defect at the ISCH site and the laterality of the defect were also noted.

Results

Patients with Type P herniation had a good postoperative recovery, and those with a Type C location had significant severe preoperative lower-extremity paralysis and a significantly poor postoperative recovery. Patients with a bone defect had a significantly severe preoperative myelopathy, but showed no difference in postoperative recovery.

Conclusions

The authors' results showed that a Type C classification and a bone defect have strong relationships with severity of symptoms and surgical outcome and are important imaging and clinical features for ISCH. These findings may allow surgeons to determine the severity of preoperative symptoms and the probable surgical outcome from imaging.
Quality of life assessment after central corpectomy for cervical spondylotic myelopathy: comparative evaluation of the 36-Item Short Form Health Survey and the World Health Organization Quality of Life–Bref
Authors: Thakar Sumit , Christopher Solomon , Rajshekhar Vedantam
Published: February 2011

Object

In this study, the authors assessed the construct validity and the reliability of the World Health Organization Quality of Life–Bref (WHOQOL-Bref) questionnaire in patients with cervical spondylotic myelopathy (CSM) and compared the performance of the WHOQOL-Bref and the 36-Item Short Form Health Survey (SF-36) in assessing quality of life (QOL) in patients with CSM.

Methods

In this prospective study, 70 patients with CSM were assessed preoperatively and again 1 year after central corpectomy using the Nurick scale, the SF-36, and the WHOQOL-Bref. Construct validity and reliability of the WHOQOL-Bref, its responsiveness compared with that of the SF-36, and the correlations between the 2 scales were studied.

Results

The WHOQOL-Bref was found to be valid (p < 0.001, Cuzick test for trend between the physical domain of the WHOQOL-Bref and Nurick grade) and reliable (Cronbach α > 0.7). It had smaller floor and ceiling effects (ranges 1.4–7.1% and 0–7.1%, respectively) than the SF-36 (ranges 2.9–71.4% and 0–14.1%, respectively). There was significant postoperative improvement in patient scores on all the SF-36 scales (p < 0.001) and the physical, psychological, and environment domains of the WHOQOL-Bref (p < 0.001). The SF-36 scales were more responsive to change (relative efficiency range 0.24–1) than the WHOQOL-Bref domains (relative efficiency range 0.002–0.73). Among scales measuring similar concepts, only the physical functioning and bodily pain scales of the SF-36 had a moderate correlation (r = 0.57 and 0.53, respectively; p < 0.001) with the physical domain of WHOQOL-Bref. Many of the scales of these 2 QOL instruments unexpectedly had a fair correlation with one another (r range = 0.2–0.4).

Conclusions

The WHOQOL-Bref, like the SF-36, is valid and reliable in assessing outcome in patients with CSM. It measures impairment in CSM in a more uniform manner than the SF-36, but its domains are less responsive to postoperative changes. Because the WHOQOL-Bref measures different constructs and has additive value, it should be used along with the SF-36 for QOL assessment in patients with CSM.
Importance of the vasculature in cyst formation after spinal cord injury
Authors: Rooney Gemma E. , Endo Toshiki , Ameenuddin Syed , Chen Bingkun , Vaishya Sandeep , Gross LouAnn , Schiefer Terry K. , Currier Bradford L. , Spinner Robert J. , Yaszemski Michael J. , Windebank Anthony J.
Published: February 2011

Object

Glial scar and cystic formation greatly contribute to the inhibition of axonal regeneration after spinal cord injury (SCI). Attempts to promote axonal regeneration are extremely challenging in this type of hostile environment. The objective of this study was to examine the surgical methods that may be used to assess the factors that influence the level of scar and cystic formation in SCI.

Methods

In the first part of this study, a complete transection was performed at vertebral level T9–10 in adult female Sprague-Dawley rats. The dura mater was either left open (control group) or was closed using sutures or hyaluronic acid. In the second part of the study, complete or subpial transection was performed, with the same dural closure technique applied to both groups. Histological analysis of longitudinal sections of the spinal cord was performed, and the percentage of scar and cyst formation was determined.

Results

Dural closure using sutures resulted in significantly less glial scar formation (p = 0.0248), while incorporation of the subpial transection surgical technique was then shown to significantly decrease cyst formation (p < 0.0001).

Conclusions

In this study, the authors demonstrated the importance of the vasculature in cyst formation after spinal cord trauma and confirmed the importance of dural closure in reducing glial scar formation.
Surgical treatment of spontaneous spinal epidural hematoma: a 5-year experience
Authors: Liao Cheng-Chih , Hsieh Po-Chuan , Lin Tzu-Kang , Lin Chih-Lung , Lo Yang-Lan , Lee Sai-Cheung
Published: February 2011

Object

Spontaneous spinal epidural hematoma (SSEH) is a rare disease. The goal of this study was to clarify the treatment results and management options in SSEH.

Methods

Patients with SSEH who were surgically treated in the authors' center between June 2003 and June 2008 were included in this study. Patients were treated as early as possible if their neurological deficits were incomplete or had been complete for 12 hours or less. The patients were assigned to 1 of 2 groups based on completeness of preoperative cord dysfunction (complete vs incomplete deficit). Surgical outcomes of the 2 groups were compared by functional performance, coded as Nurick grades at 1, 3, and 6 months after the operation. Also compared were duration of hospital stay and the number of days needed to regain the ability to function independently (defined as Nurick Grades 1 and 2) after the operation.

Results

There were 17 patients (7 female and 10 male) with pathologically confirmed SSEH. Coagulopathy, greater size (length) of SSEH, and preoperative complete spinal dysfunction were found to contribute to poor postoperative functional recovery (p < 0.05). Patients with incomplete preoperative deficits (ASIA Impairment Scale Grades B, C, and D) were able to achieve functional independent recovery within a month after surgery and had significantly better outcomes (lower Nurick grades) at 1, 3, and 6 months postoperatively than those with complete deficits (p < 0.001, p = 0.027, and p = 0.027, respectively). Median time to independent functional recovery and median length of hospital stay were significantly shorter in patients with incomplete preoperative deficits than in those with complete deficits (6 vs 110 and 9 vs 58 days, respectively; both p < 0.001).

Conclusions

Impaired preoperative hemostasis contributes to larger size of SSEH, high probability of postoperative recurrence of spinal epidural hematoma, and poor functional recovery following surgical evacuation. Incomplete spinal cord dysfunction before surgery predicts good outcome and warrants emergent evacuation of SSEH especially in the cervical and thoracic regions, where the clots are located in proximity to the spinal cord.
Utility of modified transarticular screw in the middle and lower cervical spine as intermediate fixation in posterior long fusion surgery
Authors: Miyamoto Hiroshi , Sumi Masatoshi , Uno Koki
Published: February 2011

Object

The use of a pedicle screw (PS) in the cervical spine ensures strong fixation. However, 6.7–29% of such screws appear to be malpositioned using manual insertion techniques, especially at C-3 to C-6 where the pedicle diameter is smaller, potentially causing catastrophic complications such as vertebral artery (VA) and spinal cord or nerve root injuries. To optimize safety, the authors use a new technique: cephalad and/or caudad ends at C-2 and C-7/T-1, respectively, are fixed with PSs, and intermediate points around C3–6 are fixed using a modified transarticular screw technique that captures 3 dorsal cortices and preserves the ventral cortex of the facet in posterior long fusion surgery involving occipitospinal fixation. The purpose of the present study was to demonstrate this technique and evaluate the clinical and radiological outcomes.

Methods

Thirty-nine patients, 8 men and 31 women, with a mean age of 61.7 ± 11.0 years at surgery, were included in the study. Twenty-eight occipitospinal fusions and 11 posterior long fusions were performed. Patients were divided into 2 groups: a rheumatoid arthritis (RA) group consisting of 26 patients and a non-RA group of 13 patients including 7 with athetoid cerebral palsy. Clinical outcomes were evaluated according to the Japanese Orthopaedic Association (JOA) score. For radiological evaluation, the Cobb angle on lateral radiographs was measured preoperatively, postoperatively, and at the final follow-up, and the degree of realignment from pre- to postoperation and the loss of correction from postoperation to the follow-up were compared between the 2 patient groups.

Results

The recovery rate of the JOA score was 50.6 ± 20.7% in the RA group and 37.3 ± 24.3% in the non-RA group. Neither VA injury nor spinal cord or nerve root injury occurred among this series. The degree of realignment was greater in the non-RA group (9.2 ± 13.9°) than the RA group (1.4 ± 12.7°) as the Cobb angle was more kyphotic preoperatively in the non-RA group (2.9 ± 18.6°) than in the RA group (17.4 ± 15.7°). However, 38.5% of patients in the non-RA group had a correction loss > 10% compared with 7.7% in the RA group; this difference was statistically significant.

Conclusions

The featured transarticular screw technique, which preserves the ventral cortex of the facet, as intermediate fixation in long fusion is a safe and easy procedure with few complications. It ensures acceptable clinical and radiological outcomes, especially in patients with RA.
Surgical site infection rates after minimally invasive spinal surgery
Authors: O'Toole John E. , Eichholz Kurt M. , Fessler Richard G.
Published: February 2011

Object

Postoperative surgical site infections (SSIs) have been reported after 2–6% of spinal surgeries in most large series. The incidence of SSI can be < 1% after decompressive procedures and > 10% after instrumented fusions. Anecdotal evidence has suggested that there is a lower rate of SSI when minimally invasive techniques are used.

Methods

A retrospective review of prospectively collected databases of consecutive patients who underwent minimally invasive spinal surgery was performed. Minimally invasive spinal surgery was defined as any spinal procedure performed through a tubular retractor system. All surgeries were performed under standard sterile conditions with preoperative antibiotic prophylaxis. The databases were reviewed for any infectious complications. Cases of SSI were identified and reviewed for clinically relevant details. The incidence of postoperative SSIs was then calculated for the entire cohort as well as for subgroups based on the type of procedure performed, and then compared with an analogous series selected from an extensive literature review.

Results

The authors performed 1338 minimally invasive spinal surgeries in 1274 patients of average age 55.5 years. The primary diagnosis was degenerative in nature in 93% of cases. A single minimally invasive spinal surgery procedure was undertaken in 1213 patients, 2 procedures in 58, and 3 procedures in 3 patients. The region of surgery was lumbar in 85%, cervical in 12%, and thoracic in 3%. Simple decompressive procedures comprised 78%, instrumented arthrodeses 20%, and minimally invasive intradural procedures 2% of the collected cases. Three postoperative SSIs were detected, 2 were superficial and 1 deep. The procedural rate of SSI for simple decompression was 0.10%, and for minimally invasive fusion/fixation was 0.74%. The total SSI rate for the entire group was only 0.22%.

Conclusions

Minimally invasive spinal surgery techniques may reduce postoperative wound infections as much as 10-fold compared with other large, modern series of open spinal surgery published in the literature.
Cross-sectional magnetic resonance imaging study of lumbar disc degeneration in 200 healthy individuals
Authors: Kanayama Masahiro , Togawa Daisuke , Takahashi Chihiro , Terai Tomoya , Hashimoto Tomoyuki
Published: February 2011

Object

The current cross-sectional observational MR imaging study aimed to investigate the prevalence and risk factors of lumbar disc degeneration in a healthy population and to establish the baseline data for a prospective longitudinal study.

Methods

Two hundred healthy volunteers participated in this study after providing informed consent. The status of lumbar disc degeneration was assessed by 3 independent observers, who used sagittal T2-weighted MR imaging. Demographic data collected included age, sex, body mass index, episode(s) of low-back pain, smoking status, hours of standing and sitting, and Roland-Morris Disability Questionnaire scores. There were 68 men and 132 women whose mean age was 39.7 years (range 30–55 years). Eighty-two individuals (41%) were smokers, and the Roland-Morris Disability Questionnaire scores were averaged to 0.6/24.

Results

The prevalence of disc degeneration was 7.0% in L1–2, 12.0% in L2–3, 15.5% in L3–4, 49.5% in L4–5, and 53.0% in L5–S1. A herniated disc was observed at the corresponding levels in 0.5, 3.5, 6.5, 25.0, and 35.0% of cases respectively. Spondylolisthesis was observed in < 3% of this population. Multiple logistic regression analysis demonstrated that age and hours sitting were significantly related to L4–5 disc herniation. Episode of low-back pain, smoking status, body mass index, and hours standing did not affect the prevalence of disc degeneration.

Conclusions

The current study established the baseline data of lumbar disc degeneration in a 30- to 55-year-old healthy population for a prospective longitudinal study. Hours spent sitting significantly increased the prevalence of disc herniation, but episode of low-back pain, smoking status, obesity, and standing hours were not significant risk factors.
Surgical management of cervical degenerative disease: the evidence related to indications, impact, and outcome
Authors: Fehlings Michael G. , Arvin Babak
Published: February 2011

In this special edition of Journal of Neurosurgery: Spine, a series of systematic reviews sponsored by the Section on Disorders of the Spine and Peripheral Nerves of the American Association of Neurological Surgeons/Congress of Neurological Surgeons is presented. This collection of comprehensive reviews summarizes the medical evidence related to the surgical management of cervical degenerative disc disease. Several of the key conclusions are discussed in this introduction to the issue:

There is Class II evidence to suggest that the clinical condition remains stable when observed over a 3-year period in patients with mild-to-moderate cervical spondylotic myelopathy (CSM) and age younger than 75 years.

There is consistent Class III evidence that the duration of symptoms, and possibly advancing age, negatively affect outcome in patients with CSM.

There is Class II evidence that somatosensory evoked potentials have prognostic value in patients with CSM. There is Class I evidence to show that electromyographic abnormalities (as well as the presence of radiculopathy) are predictive of the development of myelopathy in minimally symptomatic patients with cervical stenosis and spinal cord compression.

The presence of a low signal on T1-weighted images, high signal on T2-weighted images, and the presence of cord atrophy on preoperative MR images are indicators of a poor outcome in CSM.

There is Class III evidence to show that anterior or posterior surgical approaches that effectively decompress the cervical canal promote short-term improvements in outcome. However, there appears to be a risk of late kyphosis in patients who undergo laminectomy or anterior cervical discectomy alone compared with patients in whom decompression is combined with fusion.

The use of BMP-2 is discouraged for anterior cervical spine surgery based on evidence suggesting that the risks outweigh any potential benefits.

Finally, in patients with symptomatic cervical radiculopathy, arthroplasty achieves outcomes that are equivalent to anterior cervical decompression and fusion, although evidence for superiority is lacking.

Further prospective longitudinal data are required to better define the role and timing of surgical intervention in CSM and to determine the appropriate use of cervical arthroplasty in the management of symptomatic cervical degenerative disc disease.
En bloc spondylectomy for treatment of tumor-induced osteomalacia
Authors: Sciubba Daniel M. , Petteys Rory J. , Shakur Sophia F. , Gokaslan Ziya L. , McCarthy Edward F. , Collins Michael T. , McGirt Matthew J. , Hsieh Patrick C. , Nelson Clarke S. , Wolinsky Jean-Paul
Published: February 2011

En bloc spondylectomy represents a radical resection of a spinal segment most often reserved for patients presenting with a primary extradural spine tumor or a solitary metastasis in the setting of an indolent, well-controlled systemic malignancy. The authors report a case in which en bloc spondylectomy was conducted to control a metabolically active spine tumor. A 56-year-old woman, who suffered from severe tumor-induced osteomalacia, was found to have a fibroblast growth factor-23–secreting phosphaturic mesenchymal tumor in the T-8 vertebral body. En bloc resection was conducted, leading to resolution of her tumor-induced osteomalacia. This case suggests that radical spondylectomy may be beneficial in the management of metabolically or endocrinologically active tumors of the spine.
Imaging correlation of the degree of degenerative L4–5 spondylolisthesis with the corresponding amount of facet fluid
Authors: Cho Bo Young , Murovic Judith A. , Park Jon
Published: February 2011

Object

The aim of this study was to correlate the degree of L4–5 spondylolisthesis on plain flexion-extension radiographs with the corresponding amount of L4–5 facet fluid visible on MR images.

Methods

Patients underwent evaluation at the Neurosurgical Spine Clinics of Stanford University Medical Center and National Health Insurance Medical Center (Goyang, South Korea) between January 2006 and December 2007. Only patients who were diagnosed with L4–5 degenerative spondylolisthesis (DS) and who had both lumbosacral flexion-extension radiographs and MR images available for review were eligible for this study. Each patient's dynamic motion index (DMI) was measured using the lateral lumbosacral plain radiograph and was the percentage of the degree of anterior slippage seen on flexion versus that seen on extension. Axial T2-weighted MR images of the L4–5 facet joints obtained in each patient was analyzed for the amount of facet fluid, using the image showing the widest portion of the facets. The facet fluid index was calculated from the ratio of the sum of the amounts of facet fluid found in the right plus left facets over the sum of the average widths of the right plus left facet joints.

Results

Fifty-four patients with L4–5 DS were included in this study. Of these 54 patients, facet fluid was noted on MR images in 29 patients (53.7%), and their mean DMI was 6.349 ± 2.726. Patients who did not have facet fluid on MR imaging had a mean DMI of 1.542 ± 0.820; this difference was statistically significant (p < 0.001). There was a positive linear association between the facet fluid index and the DMI in the group of patients who exhibited facet fluid on MR images (Pearson correlation coefficient 0.560, p < 0.01). In the subgroup of 29 patients with L4–5 DS who showed facet fluid on MR images, flexion-extension plain radiographs in 10 (34.5%) showed marked anterolisthesis, while the corresponding MR images did not.

Conclusions

There is a linear correlation between the degree of segmental motion seen on flexion-extension plain radiography in patients with DS at L4–5 and the amount of L4–5 facet fluid on MR images. If L4–5 facet fluid in patients with DS is seen on MR images, a corresponding anterolisthesis on weight-bearing flexion-extension lateral radiographs should be anticipated. Obtaining plain radiographs will aid in the diagnosis of anterolisthesis caused by an L4–5 hypermobile segment, which may not always be evident on MR images obtained in supine patients.
Use of pimecrolimus to prevent epidural fibrosis in a postlaminectomy rat model
Authors: Cemil Berker , Tun Kagan , Kaptanoglu Erkan , Kaymaz Figen , Cevirgen Banu , Comert Ayhan , Tekdemir Ibrahim
Published: February 2011

Object

Epidural fibrosis is the scar tissue formed over the dura mater after a laminectomy. Extensive epidural fibrosis may be an important underlying cause of failed back syndrome. Pimecrolimus, an ascomycin derivative, is one of the new classes of immunomodulating macrolactams and was specifically developed for the treatment of inflammatory diseases. This study examined the preventive effects of the local application of pimecrolimus in minimizing spinal epidural fibrosis in a rat laminectomy model.

Methods

Thirty Wistar rats were divided into 3 equal groups: control, mitomycin C (MMC), and pimecrolimus groups. Each rat underwent a laminectomy at the L-3 lumbar level. In the experimental groups, a cotton pad soaked with MMC (0.5 mg/ml) or 5 mg pimecrolimus was placed on the exposed dura mater. No treatment was performed in the control group rats. Thirty days after surgery, the rats were killed and the dura mater thickness, epidural fibrosis, and arachnoidal involvement were quantified.

Results

The mean dura thickness was measured at 9.28 ± 3.39 μm in the MMC group and at 8.69 ± 2.32 μm in the pimecrolimus group, compared with 14.70 ± 4.14 μm in the control group. In addition, the epidural fibrosis and arachnoidal involvement were reduced significantly in the treatment groups compared with the control group.

Conclusions

In this animal model, it was shown that locally applied pimecrolimus effectively reduces epidural fibrosis and dural adherence in rats that underwent lumbar laminectomy. Mitomycin C was equally effective as pimecrolimus in reducing epidural fibrosis and dural adherence in this study.
Intraosseous ultrasonography to determine the accuracy of drill hole positioning prior to the placement of pedicle screws: an experimental study
Authors: Kantelhardt Sven Rainer , Larsen Jörg , Bockermann Volker , Schillinger Wolfgang , Giese Alf , Rohde Veit
Published: February 2011

Object

Dorsal fixation with rods and pedicle screws (PSs) is the most frequently used surgery to correct traumatic and degenerative instabilities of the human spine. Prior to screw placement, screw holes are drilled along the vertebral pedicles. Despite the use of a variety of techniques, misplacement of screw holes, and consequently of the PSs, is a common problem. The authors investigated the usefulness of an intraspinal, intraosseous ultrasonography technique to determine the accuracy of drill hole positioning.

Methods

An endovascular ultrasound transducer was used for the intraluminal scanning of bore holes in trabecular bovine bone, 12 pedicle drill holes in cadaveric human spine, and 4 pedicle drill holes in a patient undergoing thoracic spondylodesis. Seven of the experimental bore holes in the cadaveric spine were placed optimally (that is, inside the pedicle) and 5 were placed suboptimally (breaching the medial or lateral cortical surface of the pedicle). Computed tomography scans were obtained in the patient and cadaveric specimen after the procedure.

Results

The image quality achieved in examinations of native bovine bone tissue, the formalin-fixed human spine specimen, and human vertebrae in vivo was equal. The authors endosonographically identified correct intrapedicular and intravertebral positions as well as poor (cortex breached) placement of drill holes.

Conclusions

Intraosseous ultrasonography is a promising technique for the investigation of PS holes prior to screw implantation, and may add to the safety of PS placement.
Percutaneous transplantation of human umbilical cord blood–derived multipotent stem cells in a canine model of spinal cord injury
Authors: Lee Jae-Hoon , Chang Hwa-Seok , Kang Eun-Hee , Chung Dai-Jung , Choi Chi-Bong , Lee Jong-Hwan , Hwang Soo-Han , Han Hoon , Kim Hwi-Yool
Published: February 2011

Object

The authors describe a method for percutaneous transplantation of human umbilical cord blood (hUCB)–derived multipotent stem cells (MSCs) under fluoroscopic guidance. The investigators then tested whether percutaneous transplantation of hUCB-derived MSCs improved neurological functional recovery after acute spinal cord injury (SCI).

Methods

The authors induced SCI in 10 dogs by percutaneous balloon compression. The 10 injured dogs were assigned randomly to the following groups (2 dogs each): Group 1, evaluated 2 weeks after sham transplantation; Group 2, evaluated 2 weeks after transplantation; Group 3, evaluated 4 weeks after sham transplantation; Group 4, evaluated 4 weeks after transplantation; and Group 5, evaluated 4 weeks after multispot transplantations. The dogs with sham transplantation (Groups 1 and 3) received the same volume of saline, as a control. A spinal needle was advanced into the spinal canal, and the investigators confirmed that the end of the spinal needle was located in the ventral part of spinal cord parenchyma by using contrast medium under fluoroscopic guidance. The hUCB-derived MSCs were transplanted into the cranial end of the injured segment in 6 injured dogs at 7 days after SCI.

Results

Two dogs in Group 2 showed no improvement until 2 weeks after transplantation. Three of 4 dogs (Groups 4 and 5) that received cellular transplants exhibited gradual improvement in hindlimb locomotion from 3 weeks after cell transplantation. The CM-DiI–labeled hUCB-derived MSCs were observed in the spinal cord lesions at 4 weeks posttransplantation and exerted a significant beneficial effect by reducing cyst and injury size. The transplanted cells were positive for NeuN, glial fibrillary acidic protein, and von Willebrand factor.

Conclusions

The percutaneous transplantation technique described here can be easily performed, and it differs from previous techniques by avoiding surgical exposure and allowing cells to be more precisely transplanted into the spinal cord. This technique has many potential applications in the treatment of human SCI by cell transplantation. The results also suggest that transplantation of hUCB-derived MSCs may have therapeutic effects that decrease cavitation for acute SCI.
Bioabsorbable instrumentation for single-level cervical degenerative disc disease: a radiological and clinical outcome study
Authors: Tomasino Andre , Gebhard Harry , Parikh Karishma , Wess Christian , Härtl Roger
Published: February 2011

Object

The authors present the radiological and clinical outcome data obtained in patients who underwent single-level anterior cervical discectomy and fusion (ACDF) for cervical spondylosis and/or disc herniation; bioabsorbable plates were used for instrumentation. The use of metallic plates in ACDF has gained acceptance as a stabilizing part of the procedure to increase fusion rates, but when complications occur with these devices, the overall effectiveness of the procedure is compromised. As a possible solution, bioabsorbable implants for ACDF have been developed. This study investigates the feasibility and radiological and clinical outcomes of the bioabsorbable plates for ACDF.

Methods

The radiological and clinical outcomes of 30 patients were investigated retrospectively. All patients presented with cervical radiculopathy or myelopathy and underwent single-level ACDF in which a bioabsorbable anterior cervical plate and an allograft bone spacer were placed at a level between C-3 and C-7. Radiological outcome was assessed based on the fusion rate, subsidence, and Cobb angle of the surgical level. Clinical outcome was determined by using a visual analog scale, the Neck Disability Index, and the Odom criteria.

Results

There were no intraoperative complications, and no hardware failure was observed. No signs or symptoms of adverse tissue reaction caused by the implant were seen. Two reoperations were necessary due to postoperative blood collections. The overall complication rate was 16.7%. After 6 months, radiographic fusion was seen in 92.3% of patients. Subsidence at 11.3 ± 7.2 months was 3.1 ± 5.8 mm (an 8.2% change over the immediately postoperative results), and the change in the sagittal curvature was –2.7 ± 2.7°. The visual analog scale score for neck and arm pain and Neck Disability Index improved significantly after surgery (p < 0.001). Overall at 19.5 months postoperatively, 83% of the patients had favorable outcomes based on the Odom criteria.

Conclusions

Absorbable instrumentation provides better stability than the absence of a plate but graft subsidence and deformity rates may be higher than those associated with metal implants. There were no device-related complications, but adverse late effects cannot be excluded. The fusion rate and outcome are comparable to the results achieved with metallic plates. The authors were satisfied with the use of bioabsorbable plates as a reasonable alternative to metal, avoiding the need for lifelong metallic implants.
Microvascular system of the lumbar dorsal root ganglia in rats. Part I: a 3D analysis with scanning electron microscopy of vascular corrosion casts
Authors: Kobayashi Shigeru , Mwaka Erisa Sabakaki , Baba Hisatoshi , Takeno Kenichi , Miyazaki Tsuyoshi , Matsuo Hideaki , Uchida Kenzo , Meir Adam
Published: February 2011

Object

So far, the morphological features of the vascular system supplying the dorsal root ganglion (DRG) have been inferred only from microangiograms. However, in the past most of these studies lacked 3D observations. This study presents the details of the microvasculature of the lumbar DRG visualized by scanning electron microscopy of vascular corrosion casts.

Methods

Wistar rats were anesthetized with intraperitoneal sodium pentobarbital. After thoracotomy, the vascular system was perfused with heparinized saline, and Mercox resin was injected into the thoracic aorta. After polymerization of the resin, the vascular casts were macerated with potassium hydroxide, washed with water, and dried. The casts were examined with a scanning electron microscope.

Results

The vascular cast of the DRG was observed to have a higher density of vessels than the nerve root. Bifurcation or anastomoses of capillaries took place at approximately right angles, in a T-shaped pattern. Within the DRG, both the arterial supply and the capillary network contained blood flow control structures (ring-shaped constrictions in the cast probably representing a vascular sphincter in the microvessel). Three types of vessels could be distinguished: tortuous, straight, and bead-like capillaries. The dilations, bulges, and tortuousness of capillaries could serve the function of locally increasing the capillary surface area in a sensory neuron.

Conclusions

The results of this study suggest a causal relationship between the metabolic demands of local neuronal activity and both the density of the capillary network and the placement of the blood flow control structures.
Effect of spinal cord signal intensity changes on clinical outcome after surgery for cervical spondylotic myelopathy
Authors: Chatley Anooj , Kumar Raj , Jain Vijendra K. , Behari Sanjay , Sahu Rabi Narayan
Published: February 2011

Object

The presence of intramedullary T2 high signal intensity changes in patients with cervical spondylotic myelopathy (CSM) indicates the existence of a chronic spinal cord compressive lesion. However, the prognostic significance of signal intensity changes remains controversial. The purpose of this study was to evaluate the effect of spinal cord T2 signal intensity changes on the outcome after surgery for CSM.

Method

In a prospective study, 64 patients with CSM who underwent surgical treatment between October 2006 and April 2008 using an anterior approach were included. Based on the clinical symptoms and signs present, the severity of neurological deficits of all patients was scored according to a modified Japanese Orthopaedic Association scale score for CSM just before the surgery and at 6 months follow-up. Recovery rates were calculated at 6 months.

Results

There were 22 patients who did not have spinal cord intensity changes on MR imaging and 44 who demonstrated high-intensity signal changes on T2-weighted images (focal or segmental). No statistically significant differences were found in recovery rates between cases with T2 signal intensity changes and those with no signal intensity changes. However, the postoperative modified Japanese Orthopaedic Association scale scores and the recovery rates were much lower in patients with multisegmental signal intensity changes compared with those without these changes or those with focal signal intensity change, and ANOVA demonstrated this difference to be statistically significant (p < 0.05).

Conclusion

Multisegmental spinal cord signal intensity changes on T2-weighted MR imaging are predictors of a poor outcome in terms of functional recovery rate in patients undergoing operations for CSM.
Effect of hyperglycemia on apoptosis of notochordal cells and intervertebral disc degeneration in diabetic rats
Authors: Won Ho-Yeon , Park Jong-Beom , Park Eun-Young , Riew K. Daniel
Published: February 2011

Object

Diabetes mellitus is thought to be an important etiologic factor in intervertebral disc degeneration. It is known that notochordal cells gradually disappear from the nucleus pulposus (NP) of the intervertebral disc with age by undergoing apoptosis. What is not known is whether diabetes has an effect on apoptotic rates of notochordal cells. The purpose of this study was to investigate the effect of hyperglycemia on apoptosis of notochordal cells and intervertebral disc degeneration in age-matched OLETF (diabetic) and LETO (control) rats.

Methods

Lumbar disc tissue (L1–2 through L5–6), including cranial and caudal cartilaginous endplates, was obtained from 6- and 12-month-old OLETF and LETO rats (40 rats, 10 in each of the 4 groups). The authors examined the NP using TUNEL, histological analysis, and Western blot for expression of matrix metalloproteinase (MMP)–1, -2, -3, and -13, tissue inhibitor of metalloproteinase (TIMP)–1 and -2, and Fas (apoptosis-related protein). The apoptosis index of notochordal cells was calculated. The degree of transition of notochordal NP to fibrocartilaginous NP was classified on a scale ranging from Grade 0 (no transition) to Grade 4 (transition > 75%). The degree of expression of MMP-1, -2, -3, and -13, TIMP-1 and -2, and Fas was evaluated by densitometry.

Results

At 6 and 12 months of age, OLETF rats showed increased body weight and abnormal 2-hour glucose tolerance tests compared with LETO rats. The apoptosis index of notochordal cells was significantly higher in the OLETF rats than in the LETO rats at both 6 and 12 months of age. The degree of transition of notochordal NP to fibrocartilaginous NP was significantly higher in the OLETF rats than in the LETO rats at 6 and 12 months of age. The expression of MMP-1, -2, -3, and -13, TIMP-1, and Fas was higher in the OLETF rats at 6 and 12 months of age. The expression of TIMP-2 was significantly higher in the OLETF rats than in the LETO rats at 6 months of age, but not at 12.

Conclusions

The findings suggest that diabetes is associated with premature, excessive apoptosis of NP notochordal cells. This results in an accelerated transition of a notochordal NP to a fibrocartilaginous NP, which leads to early intervertebral disc degeneration. It remains to be determined if these premature changes are due to hyperglycemia or some other factors associated with diabetes. Understanding the mechanism by which diabetes affects disc degeneration is the first step in designing therapeutic modalities to delay or prevent disc degeneration caused by diabetes mellitus.