bluuebunny/crossref_metadata_2025 huggingface dataset:
Vertebral synovial chondromatosis
Authors: Gallia Gary L. , Weiss Nirit , Campbell James N. , McCarthy Edward F. , Tufaro Anthony P. , Gokaslan Ziya L.
Published: May 2009

✓ Synovial chondromatosis is an uncommon disorder characterized by the formation of multiple cartilaginous nodules within the synovium, most commonly affecting large joints. Its involvement with the spine is rare; only six cases have been reported. The authors describe two patients with synovial chondromatosis involving the cervical spine. In the first case, synovial chondromatosis arose from the left C1–2 facet joint. This patient underwent a two-stage procedure including a posterior approach for tumor resection and occipitocervical fusion as well as a transmandibular circumglossal approach to the anterior craniocervical junction to complete the tumor removal. Interestingly, on histopathological examination, scattered foci of low-grade chondrosarcoma were intermixed within the synovial chondromatosis. To the authors' knowledge, this is the first report of secondary low-grade chondrosarcoma arising in vertebral synovial chondromatosis. In the second case, synovial chondromatosis involved the left C4–5 facet joint. Tumor resection and cervical fusion were performed via a posterior approach.

In this report, the authors describe the clinical presentation, radiographic findings, operative details, histopathological features, and clinicoradiological follow-up data obtained in these two patients and review the literature pertaining to this rare entity.
Positional vomiting due to a thoracic spinal dural arteriovenous fistula
Authors: Cordato Dennis J. , Davies Mark A. , Masters Lynette T. , Cremer Phillip D. , Schwartz Raymond S. , Sorby William , Becvarovski Zoran
Published: May 2009

✓ The authors report the unique case of a patient with a thoracic spinal dural arteriovenous fistula (DAVF) causing remote brainstem symptoms of positional vomiting and minimal vertigo. Magnetic resonance (MR) imaging of the brain demonstrated high signal abnormality in the medulla, presumably related to venous hypertension, and spinal MR imaging revealed markedly dilated veins along the dorsal aspect of the cord. Spinal angiography confirmed the presence of a thoracic spinal DAVF. Disconnection of the DAVF from the spine resulted in a marked improvement in symptoms and resolution of the preoperative MR imaging—documented abnormalities. The authors highlight the rare syndrome of positional vomiting as a brainstem symptom and conclude that spinal DAVFs should be considered in the differential diagnosis of high signal MR imaging abnormalities localized to the brainstem.
Percutaneous vertebroplasty for the treatment of burst fractures
Authors: Chen Jyi-Feng , Wu Chieh-Tsai , Lee Shih-Tseng
Published: May 2009

✓ Percutaneous vertebroplasty is a useful procedure for patients with vertebral osteoporotic compression fractures; however, there has been no mention in the literature of the use of percutaneous vertebroplasty for the treatment of traumatic spinal fractures. The authors report the case of a 33-year-old man who harbored L-1, L-2, and L-5 burst fractures sustained in a work-related accident. The patient was successfully treated by percutaneous vertebroplasty with polymethylmethacrylate. The authors propose this procedure as a useful intervention in selected patients with lumbar burst fractures. The complications associated with major surgical procedures are absent.
Spontaneous spinal hematomas and low-molecular-weight heparin
Authors: Heppner Peter A. , Monteith Stephen J. , Law Andrew J. J.
Published: May 2009

✓ The purpose of this article is to raise awareness of spontaneous spinal hematomas that develop after administration of low-molecular-weight heparin therapy. The authors describe four patients in whom these hematomas developed without precipitating events while receiving a treatment dose of enoxaparin (Clexane) (∼1 mg/kg). Spontaneous spinal hematomas (not related to trauma, surgery, or lumbar puncture) are a rare clinical entity. Several causes have been identified, including acquired and congenital clotting abnormalities and underlying vascular lesions. Aspirin, warfarin, tissue plasminogen activator, and heparin have all been implicated in causing spinal hematomas. Concerns regarding the use of low-molecular-weight heparin agents in neuraxis anesthesia have been well documented. Their possible contribution to nontraumatic spinal hematomas has been less well described. The authors believe that low-molecular-weight heparin agents present a small but significant risk of spinal hematoma. This should be considered when prescribing therapy because such a complication may be catastrophic.
Paleopathological examination of medieval spines with exceptional thoracic kyphosis most likely secondary to spinal tuberculosis
Authors: Weber Jochen , Czarnetzki Alfred , Pusch Carsten M.
Published: May 2009

✓ Spinal tuberculosis (TB) infrequently involves more than one to three vertebrae, and kyphotic angulation of greater than 30° is rare in paleopathological specimens and clinical studies. The authors describe findings obtained in two spines (dating from the Early and Late Middle Ages). Spinal TB was present in both as well as sharply angulated kyphosis (∼ 180°) resulting from complete destruction of five and seven vertebral bodies, respectively. In these two specimens obtained in individuals older than 12 years of age at the time of death we observed no involvement of the disease in posterior vertebral elements, and the laminae showed osseous fusion without signs of infection. The osseous diameter of the spinal canal was not narrowed in either case. These findings are discussed in the context of modern medical knowledge and paleopathological and genetic examinations.
Multimodality intraoperative monitoring during complex lumbosacral procedures: indications, techniques, and long-term follow-up review of 61 consecutive cases
Authors: Krassioukov Andrei V. , Sarjeant Roger , Arkia Homan , Fehlings Michael G.
Published: May 2009

Object. The purpose of this study was to examine the neurological outcomes after complex lumbosacral surgery in patients undergoing multimodality neurophysiological monitoring.

Methods. Sixty-one patients were consecutively enrolled in this study. These patients underwent complex intra- and extradural lumbosacral procedures with concomitant intraoperative electromyography (EMG) monitoring of the lower-limb muscles, external anal and urethral sphincters (EAS and EUS), and lower-limb somatosensory evoked potentials (SSEPs). Long-term (minimum 2-year) clinical follow-up data were obtained in all cases.

Most patients were treated for spinal/spinal cord tumors (61%) or adult tethered cord syndrome (25%). Recordable lower-extremity SSEPs were reported in 54 patients (89%). New postoperative neurological deficits occurred in only three patients (4.9%), and remained persistent in only one patient (1.6%) at long-term follow-up examination. In only one of these cases was a significant decrease in SSEP amplitude detected. Spontaneous EMG activity was observed in the lower-extremity muscles and/or EAS and EUS in 51 cases (84%). Intraoperatively, EMG demonstrated activity only in the EUS in 5% of patients and only in the EAS in 28%. In seven patients (11%) spontaneous intraoperative EMG activity was observed in both the EAS and the EUS; however, in only three of these cases was EMG activity recorded in both sphincters simultaneously. In addition to spontaneously recorded EMG activity, electrically evoked EMG activity was also used as an intraoperative adjunct. A bipolar stimulating electrode was used to identify functional neural tissue before undertaking microsurgical dissection in 58 individuals (95%). In the majority of these patients, evoked EMG activity occurred either in one (33%) or in two muscles (9%) simultaneously. The presence of electrically evoked EMG activity in structures encountered during microdissection altered the plan of treatment in 24 cases (42%).

Conclusions. The authors conclude that the combined SSEP and EMG monitoring of lower-limb muscles, EAS, and EUS is a practical and reliable method for obtaining optimal electrophysiological feedback during complex neurosurgical procedures involving the conus medullaris and cauda equina. Analysis of the results indicates that these intraoperative adjunctive modalities positively influence decision making with regard to microsurgery and reduce the risk of perioperative neurological complications. Validation of the clinical value of these approaches, however, will require further assessment in a larger prospective cohort of patients.
Bone morphogenetic proteins in anterior lumbar interbody fusion: old techniques and new technologies
Authors: Burkus J. Kenneth
Published: May 2009

Object. The author reports the clinical and radiographic outcomes obtained in three prospective multicenter clinical trials in which recombinant human bone morphogenetic protein—2 (rhBMP-2) was used in anterior lumbar interbody fusion (ALIF).

Methods. Stand-alone interbody fusion cages were used, and supplemental fixation was not performed as part of the study protocol. Patients were randomly assigned to one of two ALIF groups: one in which autologous iliac crest bone graft was used (control) and one in which an rhBMP-2—coated absorbable collagen sponge was placed (investigational group). In all patients who underwent rhBMP-2—augmented fusion, imaging demonstrated evidence of bone induction and early incorporation of the cortical allografts. Overall, more expedient clinical improvements and higher success rates were observed in the rhBMP-2 group.

Conclusions. In these studies it was shown that rhBMP-2 is a safe and effective material for facilitating ALIF and for decreasing pain and improving clinical outcomes.
Clinical outcomes and complications associated with pedicle screw fixation—augmented lumbar interbody fusion
Authors: Rivet Dennis J. , Jeck David , Brennan James , Epstein Adrian , Lauryssen Carl
Published: May 2009

Object. The authors conducted a prospective study to evaluate the clinical and radiological outcomes and complications associated with uni- and bilateral transforaminal lumbar interbody fusion (TLIF) performed using carbon fiber Brantigan I/F Cages and pedicle screw fixation.

Methods. Forty-two consecutive patients who had undergone uni- or bilateral TLIF between February 1999 and July 2000 were prospectively evaluated. Clinical outcome was graded using a modified Prolo Scale, the McGill Pain Index Scale, a follow-up questionnaire, and charts. An independent radiologist assessed radiological outcomes. All patients were followed for at least 1 year.

Based on Prolo Scale scores, an excellent or good 1-year outcome was achieved in 73% of patients; 90% of patients responded that they would undergo the procedure again. At 1 year, radiographic fusion was demonstrated in 74% and was statistically related to clinical outcome (p < 0.05).

There were no deaths or major hardware failures. Complications requiring repeated surgery included one case of cerebrospinal fluid (CSF) leakage and one case in which the hemovac drain was retained. There were four cases involving minor wound infections, eight involving CSF leaks, and none requiring repeated surgery. On routine follow-up radiography one pedicle screw was found to be broken; the patient remained asymptomatic and fusion occurred.

Conclusions. Unilateral and bilateral TLIF involving placement of carbon fiber cages and pedicle screw fixation are effective treatment options in patients with indications for lumbar arthrodesis. The procedures result in acceptable rates of fusion and clinical success, and a minimal incidence of morbidity when performed by an experienced surgeon.
Vertical atlantoaxial distraction injuries: radiological criteria and clinical implications
Authors: Gonzalez L. Fernando , Fiorella David , Crawford Neil R. , Wallace Robert C. , Feiz-Erfan Iman , Drumm Denise , Papadopoulos Stephen M. , Sonntag Volker K.H.
Published: May 2009

Object.The authors sought to establish radiological criteria for the diagnosis of C1–2 vertical distraction injuries.

Methods.Conventional radiography, computerized tomography (CT), and magnetic resonance (MR) imaging findings in five patients with a C1–2 vertical distraction injury were correlated with their clinical history, operative findings, and autopsy findings. The basion—dens interval (BDI) and the C-1 and C-2 lateral mass interval (LMI) were measured in 93 control patients who underwent CT angiography; these measurements were used to define the normal BDI and LMI. The MR imaging results obtained in 30 healthy individuals were used to characterize the normal signal intensity of the C1–2 joint. The MR imaging results were compared with MR images obtained in five patients with distraction injuries.

In the 93 patients, the BDI averaged 4.7 mm (standard deviation [SD] 1.7 mm, range 0.6–9 mm) and the LMI averaged 1.7 mm (SD 0.48 mm, range 0.7–3.3 mm). Based on CT scanning in the five patients with distraction injuries, the BDIs (mean 11.9 mm, SD 3.2 mm; p < 0.001) and LMIs (mean 5.5 mm, SD 2 mm; p < 0.0001) were significantly greater than in the control group. Fast—spin echo inversion-recovery MR images obtained in these five patients revealed markedly increased signal distributed throughout the C1–2 lateral mass articulations bilaterally.

Conclusions.In 95% of healthy individuals, the LMI ranged between 0.7 and 2.6 mm. An LMI greater than 2.6 mm indicates the possibility of a distraction injury, which can be confirmed using MR imaging. Patients with a suspected C1–2 distraction injury may be candidates for surgical fusion of C1–2.
Single-stage posterolateral transpedicular approach for resection of epidural metastatic spine tumors involving the vertebral body with circumferential reconstruction: results in 140 patients
Authors: Wang Jeremy C. , Boland Patrick , Mitra Nandita , Yamada Yoshiya , Lis Eric , Stubblefield Michael , Bilsky Mark H.
Published: May 2009

Object.Patients with metastatic spine tumors often have multicolumn involvement and high-grade epidural compression, requiring circumferential decompression and instrumentation. Secondary medical and oncological issues add morbidity to combined approaches. The authors present their experience in using the single-stage posterolateral transpedicular approach (PTA) to decompress the spine circumferentially and to place instrumentation.

Methods.From September 1997 to February 2004, 140 patients with spine metastases underwent the PTA. Magnetic resonance imaging revealed high-grade spinal cord compression in 120 patients (86%) and lytic vertebral body destruction in all patients. Preoperatively 84 patients (60%) received radiotherapy directed to the involved level and 42 (30%) underwent tumor embolization. Following circumferential decompression, all patients underwent anterior reconstruction with polymethylmethacrylate and Steinmann pins, and posterior segmental fixation.

The median operative time was 5.1 hours, the median blood loss was 1500 ml, and the median hospital stay was 9 days. Ninety-six percent of the patients experienced postoperative pain improvement and improvement in or stabilization of neurological status. In 51 nonambulatory patients with poor Eastern Cooperative Oncology Group grades, 75% regained the ability to walk. One month postoperatively 90% of patients achieved good-to-excellent performance scores.

The overall median patient survival time was 7.7 months. Patients with colon and lung carcinomas had significantly shorter survival times. Major operative complications occurred in 20 patients (14.3%). Wound complications occurred in 16 patients (11.4%), but this was not correlated with preoperative radiation treatment.

Conclusions.The PTA allows circumferential epidural tumor decompression and the placement of anterior and posterior spinal column instrumention. Immediate spinal stability is achieved without the use of brace therapy. This technique achieved a high success rate for pain palliation, neurological preservation, and functional improvement, while avoiding the morbidity associated with combined approaches.
An anatomical study of the C-2 pedicle
Authors: Naderi Sait , Arman Candan , Güvençer Mustafa , Korman Esin , ŞsenoğLu Mehmet , Tetik Süleyman , Arda Nuri
Published: May 2009

Object. The C-2 pedicle plays an important role regarding screw purchase for spinal fixation. The aim of this study was to measure the C-2 pedicle—related linear and angular parameters.

Methods. Seven parameters in 160 C-2 pedicles (80 dry vertebrae) were measured using a Vernier caliper (accurate to 0.1 mm) and goniometer. The Student t-test was used to determine statistical significance.

The authors found that the C-2 isthmus (pars interarticularis) and the C-2 pedicle are distinct structures. The C-2 isthmus covers the pedicle. The isthmus is present between the superior and inferior articular processes, and the pedicle is the structure beneath the C-2 isthmus. It connects the lateral mass—inferior articular process to the body of the axis. The heights of the right and the left C-2 pediculoisthmic components (PICs) were 10.3 ± 1.6 and 9.9 ± 1.5 mm, respectively. The posterior part of the superior aspect of the PIC was wider than the anterior portion. The widths of the posterosuperior aspect of the PIC were 11.1 ± 2 and 11 ± 1.7 mm on the right and left sides, whereas the widths of the anterosuperior aspect of the PIC were 7.9 ± 1.7 and 8.5 ± 1.6 mm, respectively. The inferior widths of this component were 6.0 ± 1.5 and 5.5 ± 1.3 mm on the right and left side, respectively. The lengths of the component were 28.8 ± 2.9 mm on the right and 28.8 ± 3.4 mm on the left side. The PIC exhibits a lateral-to-medial and an inferior-to-superior angle. Its axial angles were 28.4 ± 2.5 and 28.6 ± 2.2° on the right and left sides, respectively; its sagittal angles were 18.8 ± 2.1 and 18.8 ± 1.7°, respectively.

Conclusions. The C-2 pedicle can be seen in the inferior aspect of the vertebra, and it connects posterior vertebral elements (that is, the lateral mass and inferior articular process) to the axial body. The isthmus drapes the pedicle. The authors suggest that this be termed “the pediculoisthmic component.”
Inhibition of the nuclear factor—κB activation with pyrrolidine dithiocarbamate attenuating inflammation and oxidative stress after experimental spinal cord trauma in rats
Authors: La Rosa Giovanni , Cardali Salvatore , Genovese Tiziana , Conti Alfredo , Di Paola Rosanna , La Torre Domenico , Cacciola Fabio , Cuzzocrea Salvatore
Published: May 2009

Object.The nuclear factor—κB (NF-κB) is a transcription factor that plays a pivotal role in the induction of genes involved in physiological processes and in the response to inflammation. The authors of recent studies have demonstrated that NF-κB and oxidative stress contribute to secondary injury after impact-induced spinal cord injury (SCI) in the rat. Dithiocarbamates are antioxidants that are potent inhibitors of NF-κB. The authors postulated that pyrrolidine dithiocarbamate (PDTC) would attenuate NF-κB—related inflammatory and oxidative events that occur after SCI.

Methods.Spinal cord injury was induced by the application of vascular clips (force of 50 g) to the dura mater after a four-level T5–8 laminectomy. The authors investigated the effects of PDTC (30 mg/kg administered 30 minutes before SCI and 6 hours after SCI) on the development of the inflammatory response associated with SCI in rats. Levels of myeloperoxidase activity were measured as an indicator of polymorphonuclear infiltration; malondialdehyde levels in the spinal cord tissue were determined as an indicator of lipid peroxidation. The following studies were performed: immunohistochemical analysis to assess levels of inducible nitric oxide synthase (iNOS), nitrotyrosine formation, poly([adenosine diphosphate]-ribose) polymerase (PARP) activity; Western blot analysis to determine cytoplasmic levels of inhibitory—κB-α (IκB-α); and electrophoretic mobility-shift assay to measure the level of DNA/NF-κB binding.

The PDTC treatment exerted potent antiinflammatory effects with significant reduction of polymorphonuclear cell infiltration, lipid peroxidation, and iNOS activity. Furthermore, administration of PDTC reduced immunohistochemical evidence of formation of nitrotyrosine and PARP activation in the spinal cord section obtained in the SCI-treated rats. Additionally, PDTC treatment significantly prevented the activation of NF-κB (electrophoretic mobility-shift assay and immunoblot analysis).

Conclusions.Overall, the results clearly demonstrate that PDTC-related prevention of the activation of NF-κB reduces the development of some secondary injury events after SCI. Therefore, inhibition of NF-κB may represent a novel approach in the treatment of SCIs.
Mechanically engineered hydrogel scaffolds for axonal growth and angiogenesis after transplantation in spinal cord injury
Authors: Bakshi Ajay , Fisher Omar , Dagci Taner , Himes B. Timothy , Fischer Itzhak , Lowman Anthony
Published: May 2009

Object. Spinal cord injury (SCI) is a complex pathological entity, the treatment of which requires a multipronged approach. One way to integrate different therapeutic strategies for SCI is to develop implantable scaffolds that can deliver therapies in a synergistic manner. Many investigators have developed implantable “bridges,” but an important property of such scaffolds—that is, mechanical compatibility with host tissues—has been neglected. In this study, the authors evaluated the results of implanting a mechanically matched hydrogel-based scaffold to treat SCI.

Methods. A nonbiodegradable hydrogel, poly(2-hydroxyethylmethacrylate) (PHEMA), was engineered using thermally initiated free radical solution polymerization. Two groups of 12 adult Sprague—Dawley rats underwent partial cervical hemisection injury followed by implantation of either PHEMA or PHEMA soaked in 1 µg of brain-derived neurotrophic factor (BDNF). Four rats from each group were killed 1, 2, or 4 weeks after induction of the injury. Immunofluorescence staining was performed to determine the presence of scarring, cellular inflammatory responses, gliosis, angiogenesis, and axonal growth in and around the implanted scaffolds.

Conclusions. The implanted PHEMA with 85% water content had a compressive modulus of 3 to 4 kPa, which matched the spinal cord. Implanted PHEMA elicited modest cellular inflammatory responses that disappeared by 4 weeks and minimal scarring was noted around the matrix. Considerable angiogenesis was observed in PHEMA, and PHEMA soaked in BDNF promoted axonal penetration into the gel. The authors conclude that mechanically engineered PHEMA is well accepted by host tissues and might be used as a platform for sustained drug delivery to promote axonal growth and functional recovery after SCI.
Laminoplasty for cervical myelopathy caused by subaxial lesions in rheumatoid arthritis
Authors: Mukai Yoshihiro , Hosono Noboru , Sakaura Hironobu , Ishii Takahiro , Fuchiya Tsuyoshi , Fijiwara Keiju , Fuji Takeshi , Yoshikawa Hideki
Published: May 2009

Object. Although controversy exists regarding surgical treatment for rheumatoid subaxial lesions, no detailed studies have been conducted to examine the efficacy of laminoplasty in such cases. To discuss indications for laminoplasty in rheumatoid subaxial lesions, the authors retrospectively investigated clinical and radiological outcomes in patients who underwent laminoplasty for subaxial lesions.

Methods. Thirty patients (11 men and 19 women) underwent laminoplasty for rheumatoid subaxial lesions. The patients were divided into those with mutilating-type rheumatoid arthritis (RA) and those with nonmutilating-type RA according to the number of eroding joints. As of final follow-up examination laminoplasty resulted in improvement of myelopathy in 24 patients (seven with mutilating- and 17 with nonmutilating-type RA) and transient or no improvement in six (five with mutilating- and one with nonmutilating-type RA). In the group with mutilating-type RA, significantly poorer results were displayed (p < 0.05). In most patients preoperative radiographs demonstrated vertebral slippage less than or equal to 5 mm at only one or two levels. Postlaminoplasty deterioration of subaxial subluxation and unfavorable alignment change occurred significantly more often in patients with mutilating-type RA (p < 0.05).

Conclusions. Patients with nonmutilating-type RA can benefit from laminoplasty for myelopathy due to subaxial lesions.
Anterior correction of cervical kyphotic deformity: effects on myelopathy, neck pain, and sagittal alignment
Authors: Ferch Richard D. , Shad Amjad , Cadoux-Hudson Tom A. D. , Teddy Peter J.
Published: May 2009

Object. Cervical myelopathy may develop as a result of spinal cord compression with or without deformity. The effect of persistent kyphotic deformity on the ability of the cervical cord to recover following decompressive surgery is not known.

Methods. Between 1997 and 2000, a total of 28 patients with progressive myelopathy and kyphotic deformity underwent anterior decompression, deformity correction (0–4° of lordosis), and fusion with anterior plating. Patients received clinical and radiological follow-up care, with independent analysis. Variables assessed included patient characteristics, severity of preoperative myelopathy, neck pain, and cervical sagittal alignment.

Twenty-six patients (93%) underwent follow-up review for a minimum of 18 months. Two patients died: one died in the perioperative period and was excluded from further analysis, and in the other only 3 months of follow-up data could be obtained. Local deformity was corrected to neutral or lordosis in 24 cases (89%), and the overall cervical curve was corrected to neutral or lordosis in 20 cases (74%). There was a significant improvement in myelopathy scores in those patients in whom the target (0 to 4° of lordosis) local angle was achieved (p = 0.04). There was a variable change in overall cervical sagittal alignment following local correction. Improvement in myelopathy was unrelated to patient age, previous surgery, or number of segments fused. Improvement in pain score was not related to correction of kyphotic angle.

Conclusions. The correction of sagittal alignment may promote recovery in spinal cord function in patients with kyphotic deformity.
Tracheostomy placement in patients with complete cervical spinal cord injuries: American Spinal Injury Association Grade A
Authors: Harrop James S. , Sharan Ashwini D. , Scheid Edward H. , Vaccaro Alexander R. , Przybylski Gregory J.
Published: May 2009

Object. The authors sought to identify variables that predispose patients with acute American Spinal Injury Association (ASIA) Grade A cervical spinal cord injury (SCI) to require tracheostomies for ventilator support or airway protection.

Methods. A retrospective analysis was performed of 178 consecutive patients with a cervical ASIA Grade A SCI who were admitted through the Delaware Valley SCI Center at Thomas Jefferson Hospital during a 6-year period. Exclusion criteria included injury occurring more than 48 hours prior to admission, death within 14 days of admission or nontraumatic SCI. Twenty-two patients were excluded based on these criteria. Parameters evaluated in the remaining population (156 patients) included demographics, cervical vertebral ASIA level, tracheostomy placement, pneumonia, premorbid pulmonary disease, smoking history, evidence of direct thoracic/lung trauma, operative intervention, associated appendicular trauma, and preexisting medical comorbidities.

The ASIA classification of the 156 patients included in this analysis were C-2 (eight), C-3 (11), C-4 (64), C-5 (36), C-6 (20), C-7 (13), and C-8 (four). Tracheostomies were performed in 107 of these 156 patients. Statistical analysis revealed a significant relationship between tracheostomy and patient age (p = 0.0048), preexisting medical conditions (p = 0.0417), premorbid lung disease (p = 0.0177), higher cervical ASIA level (p < 0.0001), and the presence of pneumonia (p < 0.0001). No patient with a C-8 ASIA A injury required tracheostomy, whereas all C-2 and C-3 ASIA A—injured patients underwent tracheostomies. Patients older than 45 years of age with ASIA A levels between C-4 and C-7 more commonly required tracheostomy (p < 0.005) than patients younger than 45 years of age.

Conclusions. Several risk factors were identified that corresponded to the frequent tracheostomy placement in the acute injury phase after complete cervical SCI. Early tracheostomy may be considered in patients with multiple risk factors to reduce duration of stay in the intensive care unit and facilitate ventilatory weaning.
Experience in the surgical management of spontaneous spinal epidural hematoma
Authors: Liao Cheng-Chih , Lee Shih-Tseng , Hsu Wen-Chin , Chen Li-Rong , Lui Tai-Ngar , Lee Sai-Cheung
Published: May 2009

Object. Spontaneous spinal epidural hematoma (SSEH) is a rare disease entity. Although many cases have been reported in the literature, controversy persists as to its origin, diagnosis, and timing of treatment. The authors conducted a study in patients treated in their hospital and report the results.

Methods. Clinical data obtained in 35 patients with SSEH were retrospectively reviewed. Age, sex, history of hypertension, and history of anticoagulation therapy were recorded, and data were analyzed to clarify the possible predisposing factors of SSEH. Neurological outcomes were reappraised using a standardized grading system and correlated with the time interval from initial ictus to surgery, duration of complete neurological deficits, and the rapidity of deterioration of paralysis. Nonparametric methods and Spearman rank-correlation coefficients were used for statistical analysis.

Conclusions. Surgery is a safe and effective procedure to treat SSEH. The disease-related mortality rate was 5.7%, the surgery-related complication rate was 2.9%, and there were no operation-related deaths. Neurological outcome after surgery is positively correlated with preoperative neurological deficits (88.9% complete recovery in patients with incomplete neurological deficits compared with 37.5% in those with complete deficits [p < 0.001]). In patients in whom the time interval from initial ictus was shorter (< 48 hours) and in whom the duration of complete neurological symptoms was also briefer (< 12 hours), there is a positive correlation with better neurological and functional recovery (p < 0.05).
Mitomycin C in preventing spinal epidural fibrosis in a laminectomy model in rats
Authors: Lee Jin-Yul , Stenzel Werner , Ebel Heinrich , Wedekind Christoph , Ernestus Ralf-Ingo , Klug Norfrid
Published: May 2009

Object. Extensive epidural fibrosis after lumbar surgery may be the underlying cause in most cases of failed—back surgery syndrome. Various materials have been used to prevent epidural fibrosis, but only moderate success has been shown.

Mitomycin C, an alkylosing antibiotic substance isolated from Streptomyces caespitosus, potentially supresses fibroblast proliferation after surgery. In this study, the authors investigated the effect of mitomycin C by local application on spinal epidural fibrosis in a rat laminectomy model.

Methods. Five Wistar rats underwent laminectomy at cervical, thoracic, and lumbar levels. Based on data obtained from ophthalmological studies, mitomycin C was applied to the laminectomy sites in various concentrations (0.01, 0.05, and 0.1 mg/ml). One laminectomy site in each rat was left untreated and thus served as a control. Evoked potentials were measured pre- and postoperatively, and all rats underwent clinical evaluation. Mobility status and evidence of neurological deficit were recorded. Twelve weeks later, the rats were killed, and the spinal column, including surrounding muscle tissue, was removed en bloc, decalcified, and fixed in formaldehyde. Epidural fibrosis was evaluated histologically.

In all mitomycin C—treated laminectomy sites, epidural scarring was significantly reduced compared with control sites. Remarkably, dural adhesions were absent in laminectomy defects treated with mitomycin C concentrations of 0.05 and 0.1 mg/ml. Moderate to marked epidural fibrosis with adhesion to the dura mater was noted at sites receiving 0.01 mg/ml of mitomycin C. All control sites showed dense epidural fibrosis with marked dura adherence.

Conclusions. In this experimental model, mitomycin C applied locally at a concentration of 0.1 mg/ml effectively reduced epidural fibrosis, completely avoided dural adherence, and induced no side effects.
Transvertebral interbody cage and pedicle screw fixation for high-grade spondylolisthesis
Authors: Bozkus Hakan , Dickman Curtis A.
Published: May 2009

✓ Surgical stabilization of high-grade lumbosacral spondylolisthesis is clinically challenging, and the success of deformity reduction and fusion varies. The authors describe a patient with Grade III spondylolisthesis at L5—S1. Partial reduction was achieved and fusion involved pedicle screw fixation and a posterior transvertebral interbody cage. This patient had developed progressive spondylolisthesis after decompression and posterolateral fusion for L5—S1 spondylolisthesis failed. Clinical and early radiographic results were excellent. Transsacral cage fixation can be considered a viable option to buttress the region in which high-grade L5—S1 spondylolisthesis has been reduced. The cage provides substrate for interbody arthrodesis and acts as a biomechanical stabilizer that helps prevent pedicle screw failure.
Thoracic paraplegia due to missed thoracic compressive lesions after lumbar spinal decompression surgery
Authors: Takeuchi Akihiko , Miyamoto Kei , Hosoe Hideo , Shimizu Katsuji
Published: May 2009

✓ The authors discuss the cases of three patients in whom thoracic paraplegia developed after lumbar spinal decompressive surgery for slight lumbar spinal canal stenosis. Careful computerized tomography myelography and magnetic resonance imaging examination of the thoracic spine revealed another compressive lesion (spinal cord tumor, disc herniation, osteophyte of vertebral body, and ossification of the ligamentum flavum). Additional thoracic decompressive surgery provided partial amelioration of each patient's neurological condition. The authors suggest that to avoid such a complication physical and radiographic examination of the thoracic spine should be performed preoperatively if the lumbar imaging is inconclusive.
Giant cell ependymoma of the spinal cord
Authors: Fourney Daryl R. , Siadati Abdolreza , Bruner Janet M. , Gokaslan Ziya L. , Rhines Laurence D.
Published: May 2009

✓ Several rare histological variants of ependymoma have been described. The authors report on a patient in whom cervical spinal cord astrocytoma was originally diagnosed after evaluation of a limited biopsy specimen. More abundant tissue obtained during gross-total resection included areas of well-differentiated ependymoma. The histological features of the tumor were extremely unusual, with a major component of pleomorphic giant cells. Its histological, immunohistochemical, and electron microscopic features, however, were consistent with ependymoma. Only two cases of terminal filum and two of supratentorial giant cell variant of ependymoma have been reported. To the authors' knowledge, this represents the first case of giant cell ependymoma of the spinal cord. The clinical significance is the potential for misdiagnosis with anaplastic (gemistocytic) astrocytoma, especially in cases in whom limited biopsy samples have been obtained.
Clinical course of patients with ossification of the posterior longitudinal ligament: a minimum 10-year cohort study
Authors: Matsunaga Shunji , Sakou Takashi , Taketomi Eiji , Komiya Setsuro
Published: May 2009

Object. Ossification of the posterior longitudinal ligament (OPLL) may produce quadriplegia. The course of future neurological deterioration in patients with radiographic evidence of OPLL, however, is not known. The authors conducted a long-term follow-up cohort study of more than 10 years to clarify the clinical course of this disease progression.

Methods. A total of 450 patients, including 304 managed conservatively and 146 treated by surgery, were enrolled in the study. All patients underwent neurological and radiographical follow-up examinations for a mean of 17.6 years. Myelopathy was graded using Nurick classification and the Japanese Orthopaedic Association scale.

Fifty-five (17%) of 323 patients without myelopathy evident at the first examination developed myelopathy during the follow-up period. Risk factors associated with the evolution of myelopathy included greater than 60% OPLL-induced stenotic compromise of the cervical canal, and increased range of motion of the cervical spine. Using Kaplan—Meier analysis, the myelopathy-free rate in patients without first-visit myelopathy was 71% after 30 years. A significant difference in final functional outcome was not observed between nonsurgical and surgical cases in which preoperative Nurick grades were 1 or 2. In patients with Nurick Grade 3 or 4 myelopathy, however, only 12% who underwent surgery eventually became wheelchair bound or bedridden compared with 89% of those managed conservatively. Surgery proved ineffective in the management of patients with Grade 5 disease.

Conclusions. Results of this long-term cohort study elucidated the clinical course of OPLL following conservative or surgical management. Surgery proved effective for the management of patients with Nurick Grades 3 and 4 myelopathy.
Biomechanical evaluation of cervical lateral mass fixation: a comparison of the Roy-Camille and Magerl screw techniques
Authors: Barrey Cédric , Mertens Patrick , Rumelhart Claude , Cotton François , Jund Jérôme , Perrin Gilles
Published: May 2009

Object. The purpose of this study was to assess human cervical spine pullout force after lateral mass fixation involving two different techniques: the Roy-Camille and the Magerl techniques. Although such comparisons have been conducted previously, because of the heterogeneity of results and the importance of this procedure in clinical practice, it is essential to have data derived from a prospective and randomized biomechanical study involving a sufficient sample of human cervical spines. The authors also evaluated the influence of the sex, the vertebral level, the bone mineral density (BMD), the length of bone purchase, and the thickness of the anterior cortical purchase.

Methods. Twenty-one adult cervical spines were harvested from fresh human cadavers. Computerized tomography was performed before and after placing 3.5-mm titanium lateral mass screws from C-3 to C-6. Pullout forces were evaluated using a material testing machine. The load was applied until the pullout of the screw was observed. A total of 152 pullout tests were available, 76 for each type of screw fixation. The statistical analysis was mainly performed using the Kaplan—Meier survival method.

The mean pullout force was 266 ± 124 N for the Roy-Camille technique and 231 ± 94 N for the Magerl technique (p < 0.025). For the C3–4 specimen group, Roy-Camille screws were demonstrated to exert a significantly higher resistance to pullout forces (299 ± 114 N) compared with Magerl screws (242 ± 97 N), whereas no difference was found between the two techniques for the C5–6 specimen group (Roy-Camille 236 ± 122 N and Magerl 220 ± 86 N). Independent of the procedure, pullout strengths were greater at the C3–4 level (271 ± 114 N) than the C5–6 level (228 ± 105 N) (p < 0.05).

No significant correlation between the cancellous BMD, the thickness of the anterior cortical purchase, the length of bone purchase, and maximal pullout forces was found for either technique.

Conclusions. The difference between pullout forces associated with the Roy-Camille and the Magerl techniques was not as significant as has been previously suggested in the literature. It was interesting to note the influence of the vertebral level: Roy-Camille screws demonstrated greater pullout strength (23%) at the C3–4 vertebral level than Magerl screws but no significant difference between the techniques was observed at C5–6.
Biomechanical comparison of anterior and posterior stabilization methods in atlantoaxial instability
Authors: Kim Sung-Min , Lim T. Jesse , Paterno Josemaria , Hwang Tae-Jin , Lee Kun-Woo , Balabhadra Raju S. V. , Kim Daniel H.
Published: May 2009

Object. The authors compared the biomechanical stability of two anterior fixation procedures—anterior C1–2 Harms plate/screw (AHPS) fixation and the anterior C1–2 transarticular screw (ATS) fixation; and two posterior fixation procedures—the posterior C-1 lateral mass combined with C-2 pedicle screw/rod (PLM/APSR) fixation and the posterior C1–2 transarticular screw (PTS) fixation after destabilization.

Methods. Sixteen human cervical spine specimens (Oc—C3) were tested in three-dimensional flexion—extension, axial rotation, and lateral bending motions after destabilization by using an atlantoaxial C1–2 instability model. In each loading mode, moments were applied to a maximum of 1.5 Nm, and the range of motion (ROM), neutral zone (NZ), and elastic zone (EZ) were determined and values compared using the intact spine, the destabilized spine, and the postfixation spine.

The AHPS method produced inferior biomechanical results in flexion—extension and lateral bending modes compared with the intact spine. The lateral bending NZ and ROM for this method differed significantly from the other three fixation techniques (p < 0.05), although statistically significant differences were not obtained for all other values of ROM and NZ for the other three procedures. The remaining three methods restored biomechanical stability and improved it over that of the intact spine.

Conclusions. The PLM/APSR fixation method was found to have the highest biomechanical stiffness followed by PTS, ATS, and AHPS fixation. The PLM/APSR fixation and AATS methods can be considered good procedures for stabilizing the atlantoaxial joints, although specific fixation methods are determined by the proper clinical and radiological characteristics in each patient.
Sciatic nerve entrapment in the upper thigh caused by an injury sustained during World War II at the Battle of Anzio
Authors: Oldershaw John B. , Salem Ayman , Storrs Bruce B. , Milner Brenton , Omer George E.
Published: May 2009

✓ The authors present an unusual case of sciatic nerve entrapment due to a World War II shrapnel injury to the left thigh suffered during the battle of Anzio in 1943. The patient presented for evaluation of left lower-extremity pain in the sciatic nerve distribution. Magnetic resonance imaging of the lumbosacral spine revealed a disc bulge at L5—S1 that would not explain severe sciatica. A positive Tinel sign was present in the posterior aspect of the upper thigh at the site of a scar resulting from a World War II shrapnel injury. The patient underwent exploratory external neurolysis of the area, and the sciatic nerve was released from fibrous adhesive entrapment. The patient improved dramatically following surgery. During a 3-year follow-up period, no recurrence of symptoms was noted.
Radiation-induced malignant triton tumor associated with severe spinal cord compression
Authors: Mut Melike , Çataltepe Oğuz , Söylemezoğlu Figen , Akalan Nejat , Özgen Tunçalp
Published: May 2009

✓ Malignant triton tumor (MTT) is a variant of malignant peripheral nerve sheath tumors. The authors report a case of radiation-induced MTT in a patient with severe cervicothoracic cord compression and review the related literature. This 36-year-old man presented with pain and weakness in his left arm. His medical history was significant for a biopsy procedure involving the sampling of an aneurysmal bone cyst located at T1–3 near the left lung apex; this was performed 6 years prior to presentation and was followed by radiotherapy. Neurological examination demonstrated radicular findings involving the left C-8 and T-1 nerve roots. Neuroimaging studies revealed a large mass lesion extending from C-6 to T-2 along the vertebral column, invading the upper thoracic cavity and the adjacent lung apex, and infiltrating the paravertebral muscles. A subtotal resection was performed, but the tumor regrew extensively within a short time. It invaded the spinal canal and caused significant cord compression. The patient underwent surgery two more times for tumor debulking and to relieve progressive airway and spinal canal compromise. He eventually became quadriplegic, however, and died 13 months after diagnosis of MTT. This is the seventh case of radiation-induced MTT and the fifth of MTT with spinal canal involvement to be reported in the literature.
High cervical disc herniation presenting with C-2 radiculopathy
Authors: Deshmukh Vivek R. , Rekate Harold L. , Sonntag Volker K. H.
Published: May 2009

✓ The authors report the case of a 78-year-old man with a C2–3 disc herniation that had migrated rostrally, causing C-2 radiculopathy. The C-2 radiculopathy manifested immediately after the patient underwent placement of a ventriculoperitoneal shunt for normal-pressure hydrocephalus. Myelography and computerized tomography scanning of the cervical spine revealed an extradural lesion anterolateral to the thecal sac eccentric to the right. The patient underwent a C1–3 laminectomy, C-2 nerve root decompression, and excision of the lesion. Postoperatively the patient's radiculopathy resolved completely. To the authors' knowledge, this is the first case of a C2–3 disc herniation manifesting as C-2 radiculopathy and treated via a posterior extradural approach.
Recurrent atlantoaxial rotatory fixation in children: a rare complication of a rare condition
Authors: Crossman John E. , Thompson Dominic , Hayward Richard D. , Ransford Andrew O. , Crockard H. Alan
Published: May 2009

✓ Atlantoaxial rotatory fixation (AARF) is an uncommon condition of childhood. Occasionally AARF may recur. The authors describe the cases of four patients with recurrent AARF (RAARF).

The probable cause of the RAARF and operative procedure selected are discussed. In three cases, attempts were made to stabilize the atlantoaxial complex rather than to perform fusion to preserve the function of the joint complex.

Joint stabilization is performed by incorporating a “check ligament” into the joint construct between the axial spinous process and the atlantal lateral mass. The authors believe this technique of joint stabilization augments the strength of the joint, allowing normal, but preventing excessive, rotation, until the joint reaches physiological maturity.
Pseudoaneurysm of the thoracic radiculomedullary artery with subarachnoid hemorrhage
Authors: Yahiro Tatsumi , Hirakawa Katsuyuki , Iwaasa Mitsutoshi , Tsugu Hitoshi , Fukushima Takeo , Utsunomiya Hidetsuna
Published: May 2009

✓ The authors report a rare case of a patient with a left-sided T-5 radiculomedullary artery pseudoaneurysm who presented with spinal subarachnoid hemorrhage (SAH). The patient, a 71-year-old woman, was hospitalized for progressive paraplegia and sensory loss with bladder and rectal dysfunction. Computerized tomography scanning revealed an SAH at the posterior fossa. Spinal T2-weighted magnetic resonance imaging demonstrated SAH and an inhomogeneous and slightly low signal intensity mass at T4–5. Spinal angiography revealed a tiny masslike staining without arteriovenous shunting. The resected specimen, which caused the spinal SAH, was diagnosed as a pseudoaneurysm based on operative and pathological findings.