bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spinal meningiomas in patients younger than 50 years of age: a 21-year experience
Authors: Cohen-Gadol Aaron A. , Zikel Ofer M. , Koch Cody A. , Scheithauer Bernd W. , Krauss William E. 
Published: May 2009

Object. Spinal meningiomas occur most frequently in older patients. They are well-circumscribed and slow-growing tumors that are associated with good patient outcomes following surgery. Spinal meningiomas occurring in younger patients may be more aggressive, with a worse prognosis. The authors present their 21-year experience with spinal meningiomas in patients younger than 50 years of age.
Methods. The authors reviewed data obtained in 40 patients (age < 50 years) treated at the Mayo Clinic, Rochester, during the past 21 years; in all cases the lesions were histologically confirmed spinal meningiomas. Five men (12.5%) and 35 women (87.5%) (mean age 34.5 ± 10.9 years) underwent 52 operations for 41 tumors. The mean follow-up duration was 82 ± 93 months (range 0–445 months). The data obtained in these patients were compared with those derived from a random control cohort of 40 patients older than age 50 years in whom spinal meningiomas were resected at the Mayo Clinic during a similar period. In this cohort, there were 33 women and seven men whose mean age was 67.1 ± 9.5 years. The mean follow-up duration for the older group was 88 ± 72.3 months (range 18–309 months).
Compared with the random cohort of older patients, younger patients there tended to have more tumors located in the cervical spine (39%) as well as a greater number of predisposing factors such as neurofibromatosis Type 2, radiation exposure, or trauma. Nine (22%) of the patients younger than 50 years of age required reoperation for residual or recurrent tumor compared with two (5%) in the older patient control group. The overall mortality rate at the completion of the study for the younger patients was 10%.
Conclusions. Spinal meningiomas in younger patients have a worse prognosis than similar tumors in older patients.
Microsurgical midline approach for the decompression of extraforaminal L5—S1 stenosis
Authors: Park Youn-Kwan , Kim Joo Han , Chung Hung Seob , Suh Jung Keun 
Published: May 2009

Object. When performing surgery, the extraforaminal window is very narrow at the L5—S1 level. The authors describe a microsurgical method for decompression of the L-5 nerve root trapped between a marginal osteophyte of the vertebral body and the transverse process. The procedure was performed in 16 patients with extraforaminal stenosis.
Methods. The cranial part of the L5—S1 facet joint and the caudal portion of the pedicle and transverse process of L-5 were removed via a midline skin incision and partial resection of the pars interarticularis; a high-speed drill was used as was a surgical microscope. The affected nerve root was decompressed and mobilized cranially.
Postoperatively all patients reported excellent relief of their sciatic pain, and there were no technique-associated complications. There was no recurrence during the follow-up period, that ranged from 14 to 70 months.
Conclusions. The authors recommend this technique for the effective decompression of symptomatic extraforaminal L5—S1 stenosis. The need for a dangerous and tedious removal of the vertebral osteophyte together with spinal fusion is avoided.
Neuroprotective effects of GYKI 52466 on experimental spinal cord injury in rats
Authors: Çolak Ahmet , Soy Osman , Uzun Hafize , Aslan Özcan , Barut Seref , Belce Ahmet , Akyildiz Ayşenur , Taşyürekli Mustafa 
Published: May 2009

Object. The toxic effects of glutamate in the central nervous system are well known. This neurotoxicity occurs through metabotropic and ionotropic receptors, the latter group composed of N-methyl-d-aspartate, α-amino-3-hydroxy-5-methylisoxazole-4-proprionic acid (AMPA), and kainate receptors. The authors investigated the neuroprotective effects of GYKI 52466, a 2,3-benzodiazepine that is a selective and potent AMPA receptor antagonist, in a rat spinal cord trauma model.
Methods. Sixty Wistar albino rats were studied in three groups of 20 animals each: sham-operated controls (Group 1); spinal cord—injured rats (Group 2); and spinal cord—injured plus GYKI 52466—treated rats (Group 3). In Groups 2 and 3, spinal cord injury (SCI) was induced at the thoracic level by applying an aneurysm clip to the cord for 1 minute. One minute after the clip was removed, the rats in Group 3 received an intraperitoneal injection of 15 mg/kg GYKI 52466. Responses to injury and treatment were evaluated based on biochemical parameters (lipid peroxidation and adenosine 5′-triphosphate [ATP] levels in tissue), and on light and transmission electron microscopy findings in cord tissue collected at different times post-SCI. Five rats from each group underwent assessment of functional recovery at 1, 3, and 5 days after SCI; evaluation was performed using the inclined-plane technique and Tarlov motor grading scale.
The mean lipid peroxidation levels in Groups 1 and 2 were 21.73 ± 4.35 and 35.53 ± 2.99 nmol/g of wet tissue, respectively. The level in Group 3 was 27.98 ± 3.93 nmol/g of wet tissue, which was significantly lower than that in Group 2 (p < 0.01). The mean ATP levels in Groups 1 and 2 were 166.21 ± 25.57 and 41.72 ± 12.28 nmol/g of wet tissue, respectively. The ATP level in Group 3 was 85.82 ± 13.92 nmol/g of wet tissue, which was significantly higher than that in Group 2 (p < 0.01). Light microscopic examination of Group 2 tissues showed hemorrhage, necrosis, polymorphonuclear leukocyte infiltration, and vascular thrombi. In contrast, the examination of Group 3 tissues showed limited hemorrhage and no necrosis or vascular thrombi. The most prominent findings in Group 2 were hemorrhage and necrosis, whereas the most prominent findings in Group 3 were focal hemorrhage and leukocyte infiltration. Electron microscopy demonstrated that GYKI 52466 protected the neurons, myelin, axons, and intracellular organelles. The mean inclined-plane angles in Groups 1, 2, and 3 were 65°, 40 to 45°, and 55°, respectively. Motor scale results in all groups showed a similar trend.
Conclusions. The findings in this rat model suggest that GYKI 52466 may provide significant therapeutic protection from secondary damage after acute SCI. This agent may be a viable alternative treatment for SCI.
Spinal cord edema: unusual magnetic resonance imaging findings in cervical spondylosis
Authors: Lee Jangbo , Koyanagi Izumi , Hida Kazutoshi , Seki Toshitaka , Iwasaki Yoshinobu , Mitsumori Kenji 
Published: May 2009

Object
Spinal cord edema is a rare radiological finding in chronic degenerative disorders of the spine. Between 1997 and 2001, the authors treated six patients with cervical spondylotic myelopathy in whom postoperative spinal cord edema was demonstrated. The authors describe the radiological and clinical features of this unusual condition.

Methods
The six patients were all men, and ranged in age from 44 to 72 years. All patients presented with mild quadriparesis and underwent laminoplasty or anterior fusion. Preoperative magnetic resonance (MR) imaging revealed marked spinal cord compression with intramedullary hyperintensity on T2-weighted sequences and spinal cord enhancement at the compression level after administration of Gd.
After surgery, spinal cord edema was observed in all patients; the spinal cord appeared swollen on the postoperative MR images. Preoperative and postoperative Gd-enhanced MR imaging demonstrated clear enhancement of the white matter at the compressed segment. Neurologically, five of six patients experienced good improvement of symptoms; however, the spinal cord edema as documented on follow-up MR imaging persisted for several months after surgery.

Conclusions
The radiological characterization of spinal cord edema was based on the reversible white matter lesion most likely caused by disturbed local venous circulation induced by chronic spinal cord compression. Such unusual MR findings in cervical spondylotic myelopathy should be differentiated from intramedullary spinal cord tumors, demyelinating disorders, or inflammatory processes.
Synovial cysts of the lumbar spine: surgery-related results and outcome
Authors: Pirotte Benoit , Gabrovsky Nicolay , Massager Nicolas , Levivier Marc , David Philippe , Brotchi Jacques 
Published: May 2009

Object
The authors conducted a study to determine the surgery-related results and outcomes in patients with synovial cysts of the lumbar spine. They emphasize several specific characteristics useful in clinical management.

Methods
Forty-six consecutive patients with 54 lumbar synovial cysts underwent surgery between 1990 and 2001. A retrospective analysis of the clinical presentation and follow-up data, radiological findings, and surgical techniques was performed. Clinical presentation was dominated by acute or subacute sciatic pain. No specific symptom allowed differentiation of synovial cyst from a lumbar disc herniation. Computerized tomography scanning aided in establishing the correct diagnosis in 19 of 30 cases and magnetic resonance (MR) imaging did so in all cases. Three of the 46 patients presented with bilateral lumbar synovial cysts. The L4–5 level was affected in 61%, and radiological signs of disc degeneration/spondylosis were observed in 54% of the patients. Immediate symptom relief without local recurrence was obtained by complete microsurgical excision in which bipolar coagulation was used to remove the synovial membrane and in which the interapophysial joint was preserved. During the 1st postoperative year, a newly formed symptomatic synovial cyst developed on the contralateral side or at a superior vertebral level in five patients. They underwent surgery; results were good and there was no recurrence.

Conclusions
The findings in this series suggest that synovial cysts can occur at multiple lumbar sites within a short period of time and could be predisposed to developing in certain individuals, predominantly in women older than 40 years of age. Postoperative follow up is recommended and MR imaging mandatory in cases of recurrent sciatica.
Focal fractionated radiotherapy for intramedullary spinal arteriovenous malformations: 10-year experience
Authors: Hida Kazutoshi , Shirato Hiroki , Isu Toyohiko , Seki Toshitaka , Onimaru Rikiya , Aoyama Hidefumi , Ushikoshi Satoshi , Miyasaka Kazuo , Iwasaki Yoshinobu 
Published: May 2009

Object
Radiosurgical treatment of spinal arteriovenous malformations (AVMs) is becoming a practical therapeutic option as methodology improves, but no comparative study has yet been published on focal fractionated radiotherapy. The authors report their experience with conventional and hypofractionated radiotherapy for spinal AVM.

Methods
Candidates for this study were patients who experienced symptoms due to an intramedullary AVM but were ineligible for embolization or surgery. Of 21 patients with spinal AVMs, 10 cases in a 10-year period met this criterion. Angiography and contrast-enhanced computerized tomography scanning were used for treatment planning in all cases. Fractionated radiotherapy was performed using a linear accelerator, extracranial immobilization system, and frequent orthogonal linacographic verification. The starting radiation dose was 32 Gy in two, 36 Gy in three, and 40 Gy in two patients, in a regimen involving 1.8 to 2—Gy daily fractions; this was recently changed to a hypofractionation schedule of 30 Gy (in eight sessions) in one and 20 Gy (in four sessions) in two patients.

Results
The follow-up period ranged from 26 to 124 months (median of 49 months). There were no hemorrhages nor any adverse reactions attributable to irradiation. Of the seven patients who consented to undergo follow-up angiography, the nidus size decreased in five, but complete obliteration did not occur in any patient.

Conclusions
Because no patient experienced adverse effects, the maximum tolerable radiation dose for the spinal cord associated with an AVM could not be identified, although it presumably is higher than those administered. The lack of rebleeding in patients in whom complete angiographic occlusion was absent suggests that the natural history of spinal AVMs may be less aggressive than previously reported.
Computerized tomography—guided percutaneous transforaminodiscal biopsy sampling of vertebral body lesions
Authors: Sucu Hasan Kamil , Bezircioglu Hamdi , Çiçek Canan , Ersşahin Yusuf 
Published: May 2009

Object
The posterolateral approach is the common route for obtaining percutaneous biopsy samples in lumbar and thoracic vertebral bodies (VBs). This procedure, however, is associated with the risk of complications. Because of this, the authors devised a new method for percutaneous biopsy sampling of VB lesions.

Methods
The percutaneous computerized tomography (CT)—guided transforaminodiscal biopsy procedure was undertaken in 20 patients during a 10-month period. The VBs in 18 cases were successfully accessed using this technique. There were no procedure-related complications.

Conclusions
Transforaminodiscal CT-guided spinal biopsy procedure is a safe and effective method for accessing VB lesions. It is possible to obtain a biopsy sample in the major part of the VB. This technique is a good alternative to the standard posterolateral approach.
Image-guided resection for thoracic ossification of the ligamentum flavum
Authors: Seichi Atsushi , Nakajima Susumu , Takeshita Katsushi , Kitagawa Tomoaki , Akune Toru , Kawaguchi Hiroshi , Nakamura Kozo 
Published: May 2009

Object
The purpose of this study was to evaluate the advantages of using an image guidance system to aid in the resection of ossified of the ligamentum flavum (OLF) in the thoracic spine. The procedure and surgery-related outcome are discussed.

Methods
Ten patients with myelopathy underwent laminotomy with medial facetectomy and an image guidance system was used to remove the OLF. No neurological deterioration occurred, and postoperative computerized tomography scanning demonstrated successful decompression and good preservation of the lateral parts of the facet joints.

Conclusions
The image guidance system allows accurate resection of the OLF while preserving as much as possible the facet joints and posterior elements of the thoracic spine.
Surgical management of lumbosacral nerve root hemangioblastomas in von Hippel—Lindau syndrome
Authors: Lonser Russell R. , Wait Scott D. , Butman John A. , Vortmeyer Alexander O. , Walther McClellan M. , Governale Lance S. , Oldfield Edward H. 
Published: May 2009

Object
Hemangioblastomas in the lumbosacral region are rare, and the authors of prior reports have not defined the surgical management, histopathological features, or outcome in a group of patients after resection of these tumors. To identify features that will help guide the operative and clinical management of these lesions, the authors reviewed data obtained in a series of patients with von Hippel—Lindau syndrome who underwent resection of lumbosacral nerve root hemangioblastomas.

Methods
Six consecutive patients (three men and three women; mean age at surgery 39 years [range 31–48 years]) who underwent operations for resection of lumbosacral nerve root hemangioblastomas were included in this study. The mean follow-up period was 23 months (range 6–45 months). Data derived from examination, hospital charts, operative findings, histopathological analysis, and magnetic resonance imaging were used to analyze surgical management and clinical outcome. The resected tumors were located in the lumbar (five cases) or sacral (one case) regions; the mean tumor size was 2728 mm3 (range 80–15,022 mm3). Consistent with central nervous system (CNS) regional variation of space available to accommodate the neural compressive effect of the hemangioblastoma size, the mean tumor volume (2728 mm3) of these symptomatic lesions was much larger than that of symptomatic hemangioblastomas resected in the other regions of the CNS. Histopathological examination showed infiltration of the associated nerve root by the hemangioblastoma in each case. In five of the six patients complete resection was achieved, and in one patient intradural exploration of two hemangioblastomas was performed, but resection was not achieved because of motor root involvement. In all cases involving complete resections the patients experienced symptomatic improvement.

Conclusions
Lumbosacral nerve root hemangioblastomas can be safely removed in most patients with von Hippel—Lindau syndrome. Generally, hemangioblastomas of the lumbosacral nerve roots should be resected when they become symptomatic. Because these neoplasms appear to originate from the nerve root, it is necessary to sacrifice the nerve root from which the hemangioblastoma originates to achieve complete resection.
Topical mitomycin C—induced inhibition of postlaminectomy peridural fibrosis in rabbits
Authors: Dogulu Fikret , Kurt Gokhan , Emmez Hakan , Erdem Ozlem , Memis Leyla , Baykaner Kemali , Ceviker Necdet 
Published: May 2009

Object
The authors conducted a study to determine the effectiveness of mitomycin C in preventing postlaminectomy peridural fibrosis in rabbits.

Methods
Laminectomies were performed at L-4 in 12 rabbits. Color-coded cotton pads soaked either with 0.02% mitomycin C or saline were applied in a blinded fashion to the operative sites, with saline-treated laminectomy sites serving as controls. The rabbits were killed 30 days after surgery. The extent of peridural fibrosis was evaluated by histological analysis.
The mitomycin C—treated sites showed significantly decreased peridural fibrosis.

Conclusions
Peridural fibrosis can be a devastating condition that develops after laminectomy. Topical application of mitomycin C may be a successful method of preventing postlaminectomy peridural fibrosis.
Biomechanical comparison of expandable cages for vertebral body replacement in the cervical spine
Authors: Kandziora Frank , Pflugmacher Robert , Schaefer Jan , Scholz Matti , Ludwig Kathrin , Schleicher Philip , Haas Norbert P. 
Published: May 2009

Object
Recently, expandable cages for vertebral body replacement in the cervical spine have been developed. The purpose of this study was to compare the biomechanical properties of expandable cages with those of a tricortical iliac crest graft and a nonexpandable cage.

Methods
Forty human cervical spines (C3–5) were tested in flexion, extension, axial rotation, and lateral bending. First all motion segments were evaluated intact. After corpectomy of C-4 the spines were divided into five groups of eight and the following stabilization techniques were used: 1) autologous iliac crest bone graft; 2) mesh titanium cage; 3) anterior distraction device; 4) Synex-C titanium; and 5) Synex-C PEEK. Additionally, anterior plating and anterior plating plus posterior screw/rod fixation were applied. Stiffness, range of motion, and neutral and elastic zones were determined.
In comparison with the intact motion segment all implants significantly increased stiffness in flexion and bending, but decreased stiffness in extension. There were no biomechanical differences between the nonexpandable and expandable cages. Furthermore, there were no biomechanical differences between the tricortical iliac crest graft and the cages, except for Synex-C in rotation. Additional anterior plating significantly increased biomechanical stiffness in all test modes; particularly in rotation mode, combined anterior-posterior stabilization increased stiffness by up to 102% compared with anterior plating alone.

Conclusions
In comparison to a tricortical iliac crest bone graft and a nonexpandable cage, expandable cages have no biomechanical advantages. Due to the low extension and rotational stiffness, none of the implants can be recommended as a stand-alone device. Additional anterior plating increased biomechanical stability adequately. Therefore, additional posterior stabilization should only be considered in cases of severe rotational instability of the cervical spine.
Biomechanical analysis of multilevel cervical corpectomy and plate constructs
Authors: Porter Randall W. , Crawford Neil R. , Chamberlain Robert H. , Park Sung Chan , Detwiler Paul W. , Apostolides Paul J. , Sonntag Volker K. H. 
Published: May 2009

Object
The authors compared the biomechanical stability of two multilevel cervical constructs involving the placement of equal size anterior cervical plates (ACPs) after decompressive surgery: the first is placed after three-level corpectomy with strut graft and the second after two-level corpectomy and aggressive discectomy with strut graft. In addition, both constructs were evaluated with and without the application of a screw attaching the ACP to the strut graft to determine whether the additional screw enhanced stability in any mode of loading.

Methods
Nondestructive repeated-measures in vitro flexibility tests were performed in human cadaveric cervical spines. Nonconstraining pure moments of up to 1.5 Nm were applied while recording three-dimensional angular motion stereophotogrammetrically at each level from C4–5 to C7—T1. Nine specimens underwent the three-level corpectomy/strut graft procedure and eight specimens the two-level corpectomy/discectomy strut graft procedure. Failures during testing eliminated two of the former specimens and three of the latter specimens from analysis.
The construct applied after the two-level procedure allowed a significantly smaller normalized neutral zone during flexion—extension than the three-level construct (p = 0.04). Normalized elastic zone and range of motion were consistently smaller in the two- than in the three-level construct, but the differences were not significant. Addition of a screw to the strut graft significantly reduced motion in the three-level procedure—treated specimens during flexion and lateral bending but had no effect on two-level corpectomy—treated specimens.

Conclusions
The construct associated with the two-level corpectomy/discectomy provided better immediate postoperative stability than that associated with the three-level corpectomy. The addition of a screw to the strut graft conferred stability on the three-level construct but not the two-level construct.
Pedicle screw fixation for isthmic spondylolisthesis: does posterior lumbar interbody fusion improve outcome over posterolateral fusion?
Authors: La Rosa Giovanni , Conti Alfredo , Cacciola Fabio , Cardali Salvatore , La Torre Domenico , Gambadauro Nicola Maria , Tomasello Francesco 
Published: May 2009

Object. Posterolateral fusion involving instrumentation-assisted segmental fixation represents a valid procedure in the treatment of lumbar instability. In cases of anterior column failure, such as in isthmic spondylolisthesis, supplemental posterior lumbar interbody fusion (PLIF) may improve the fusion rate and endurance of the construct. Posterior lumbar interbody fusion is, however, a more demanding procedure and increases costs and risks of the intervention. The advantages of this technique must, therefore, be weighed against those of a simple posterior lumbar fusion.
Methods. Thirty-five consecutive patients underwent pedicle screw fixation for isthmic spondylolisthesis. In 18 patients posterior lumbar fusion was performed, and in 17 patients PLIF was added. Clinical, economic, functional, and radiographic data were assessed to determine differences in clinical and functional results and biomechanical properties.
At 2-year follow-up examination, the correction of subluxation, disc height, and foraminal area were maintained in the group in which a PLIF procedure was performed, but not in the posterolateral fusion—only group (p < 0.05). Nevertheless, no statistical intergroup differences were demonstrated in terms of neurological improvement (p = 1), economic (p = 0.43), or functional (p = 0.95) outcome, nor in terms of fusion rate (p = 0.49).
Conclusions. The authors' findings support the view that an interbody fusion confers superior mechanical strength to the spinal construct; when posterolateral fusion is the sole intervention, progressive loss of the extreme correction can be expected. Such mechanical insufficiency, however, did not influence clinical outcome.