bluuebunny/crossref_metadata_2025 huggingface dataset:
Stabilizing effect of posterior lumbar interbody fusion cages before and after cyclic loading
Authors: Kettler Annette , Wilke Hans-Joachim , Dietl Rupert , Krammer Matthias , Lumenta Christianto , Claes Lutz
Published: May 2009

Object. The function of interbody fusion cages is to stabilize spinal segments primarily by distracting them as well as by allowing bone ingrowth and fusion. An important condition for efficient formation of bone tissue is achieving adequate spinal stability. However, the initial stability may be reduced due to repeated movements of the spine during everyday activity. Therefore, in addition to immediate stability, stability after cyclic loading is of remarkable relevance; however, this has not yet been investigated. The object of this study was to investigate the immediate stabilizing effect of three different posterior lumbar interbody fusion cages and to clarify the effect of cyclic loading on the stabilization.

Methods. Before and directly after implantation of a Zientek, Stryker, or Ray posterior lumbar interbody fusion cage, 24 lumbar spine segment specimens were each evaluated in a spine tester. Pure lateral bending, flexion—extension, and axial rotation moments (± 7.5 Nm) were applied continuously. The motion in each specimen was measured simultaneously. The specimens were then loaded cyclically (40,000 cycles, 5 Hz) with an axial compression force ranging from 200 to 1000 N. Finally, they were tested once again in the spine tester.

Conclusions. In general, a decrease of movement in all loading directions was noted after insertion of the Zientek and Ray cages and an increase of movement after implantation of a Stryker cage. In all three cage groups greater stability was demonstrated in lateral bending and flexion than in extension and axial rotation. Reduced stability during cyclic loading was observed in all three cage groups; however, loss of stability was most pronounced when the Ray cage was used.
Spinal aneurysm of the lateral sacral artery
Authors: Alberstone Cary D. , Rupp Frederick W. , Anson John A.
Published: May 2009

U Spinal aneurysms are rare, and those not associated with either an arteriovenous malformation or coarctation of the aorta are particularly rare. In this report, the authors present a case of spinal aneurysm involving the lateral sacral artery. The aneurysm presented as a cauda equina syndrome 6 years after the patient underwent a renal transplant contralateral to the side of the aneurysm parent vessel. To the authors' knowledge, only one similar case has been previously reported. They conclude that spinal aneurysms should be included in the differential diagnosis of an extramedullary spinal mass lesion.
Thoracic myelopathy due to enlarged ossified yellow ligaments
Authors: Payer Michael , Bruder Elisabeth , Fischer Jan A. , Benini Arnaldo
Published: May 2009

U Enlarged ossified yellow ligaments are a rare and poorly understood cause of thoracic myelopathy. The authors report the case of a patient in whom thoracic myelopathy was caused by enlarged ossified yellow ligaments.
Retrieval of broken pedicle screws by “friction” technique
Authors: Di Lorenzo Nicola , Conti Renato , Romoli Stefano
Published: May 2009

U The authors describe a simple and fast technique for removal of deeply situated broken pedicle screw fragments.

The screw fragments are removed using a fine-serrated, conically cored bit with a light rough inner surface that is mounted on a common slow-speed drill capable of rotating clockwise and counterclockwise. The cored head of the bit is pressed and engaged on the cut surface of the broken screw, and the drill is made to turn in counterclockwise rotation; this, by means of friction, causes the two surfaces to interlock, and consequently the broken screw fragment backs out. This technique was used to retrieve both broken titanium and stainless steel screws, and satisfying results were obtained. There were no complications associated with the application of the technique, and the pedicle as well as the screw hole were always preserved, offering, in the event that the vertebral instability continued, the possibility of applying a new screw of slightly larger diameter at the same screw hole.

This technical application offers the opportunity of removing deeply situated screw fragments by using a simple technique while maintaining the vertebral pedicle and screw-hole integrity.
Hook—rod with pedicle screw fixation for unstable spinal fracture
Authors: Stančić Marin F. , Mićcović Vladimir , Potočnjak Mark
Published: May 2009

U A technique is described in which spinal fracture repositioning, decompression, and stabilization are achieved by a combination of hook—rod and pedicle screw fixation. This straightforward technique is useful for performing acute decompression in patients with partial neurological deficits and multisystem injuries. A laminectomy allows for placement of a stiffer fixation system, and it improves the insufficient canal clearance obtained when performing annulotaxis alone.
Duration of leg pain as a predictor of outcome after surgery for lumbar disc herniation: a prospective cohort study with 1-year follow up
Authors: Nygaard Øystein P. , Kloster Roar , Solberg Tore
Published: May 2009

Object. The aim of this study was to investigate different variables in the duration of symptoms that can be used to predict outcome after lumbar microdiscectomy.

Methods. In a prospective study of 132 consecutive patients who underwent surgery for lumbar disc herniation, the authors evaluated the prognostic value of different variables in the duration of symptoms for the 1-year period after surgery. The 1-year follow-up investigation was conducted by an independent observer. Assessment of outcome was performed using a clinical overall score (COS), which was recently assessed for its reliability and validity. As for factors predictive of outcome, only duration of leg pain and sick leave reached statistical significance in the multivariate analysis. Results of the univariate analysis demonstrated that in patients experiencing preoperative leg pain fewer than 4 months and between 4 and 8 months, a significantly lower COS at the 1-year follow up was demonstrated compared with those in whom the duration of leg pain was longer (> 8 months). One hundred eight patients returned to work within the 1st year after surgery. Patients who took a sick leave of more than 28 weeks before the operation were at higher risk of not returning to work.

Conclusions. Analysis of these results indicates that leg pain lasting more than 8 months correlates with an unfavorable postoperative outcome in patients with lumbar disc herniation, as well as a high risk of not returning to work.
Pathoanatomy of clinical findings in patients with sciatica: a magnetic resonance imaging study
Authors: Vroomen Patrick C. A. J. , de Krom Marc C. T. F. M. , Wilmink Jan T.
Published: May 2009

Object. Anatomical details of nerve root compression may explain the production of the signs and symptoms of sciatica. The authors of anatomical studies have offered many theories without clearly demonstrating the clinical relevance of the observations. Clinicoanatomical series are scarce and are affected to a great extent by selection bias.

Methods. We created a schematic drawing of the lumbar anatomy based on both the literature and in vitro anatomical observations. A diagnosis was then made with the aid of detailed and standardized clinical and magnetic resonance (MR) imaging studies in primary-care patients who presented with pain that radiated into the leg. Clinical and MR imaging findings were correlated. Finally, the anatomical drawing was compared with the clinical data.

The higher the vertebral level of symptomatic disc herniations, the more likely the compression will be more laterally situated. Classic symptoms of sciatica (typically, dermatomal pain; increase in pain when coughing, sneezing, or straining; and testing positive for pain during straight leg raising) were most likely to occur with compression of the nerve root in the axilla and with mediolateral disc herniations.

Conclusions. The L-3, L-4, L-5, and S-1 nerve roots each tend to be compressed at different sites along the rostrocaudal course of the nerve root. Disc herniations become symptomatic at different sites for each disc level. The schematic drawing produced a priori could well be used to explain these findings. Expectations of particular clinical findings can be predicted by specific pathoanatomical findings.
Outcome after surgical treatment of progressive posttraumatic cystic myelopathy
Authors: Lee Thomas T. , Alameda Gustavo J. , Gromelski Erika B. , Green Barth A.
Published: May 2009

Object. Progressive posttraumatic cystic myelopathy (PPCM) can occur after an injury to the spinal cord. Traditional treatment of PPCM consists of inserting a shunt into the cyst. However, some authors have advocated a more pathophysiological approach to this problem. The authors of the present study describe their surgical treatment protocol and outcome in a series of patients with syringomyelia.

Methods. Medical records of 34 patients undergoing surgical treatment for PPCM were reviewed. Laminectomies and intraoperative ultrasonography were performed. In patients without focal tethering of the spinal cord and in whom only a confluent cyst had been revealed on ultrasonography, a syringosubarachnoid shunt was inserted; in those with both tethering and a confluent cord cyst, an untethering procedure was performed first. When a significant reduction (> 50%) in the size of the cyst was shown after the untethering procedure, no shunt was inserted. When no changes in cyst size were demonstrated on ultrasonography, a short syringosubarachnoid shunt was used. The mean follow-up period was 28.7 months (range 12–102 months).

The interval between the mechanism of injury and the operation ranged from 5 months to 37 years (mean 11 years). Pain was the most frequent symptom, which was followed by motor deterioration and spasticity. Postoperative improvement was noted in 55% of patients who experienced motor function deterioration and in 53% of those who demonstrated worsening spasticity. In 14 of 18 patients with an associated tethered spinal cord, tethering alone caused significant collapse of the cyst. Postoperative magnetic resonance imaging demonstrated cyst collapse in 92% of patients who had undergone untethering alone and in 93% of those who underwent syringosubarachnoid shunt placement. Treatment failure was observed in 7% of the former group and in 13% of the latter.

Conclusions. Posttraumatic cystic myelopathy can occur with or without the presence of tethered cord syndrome. Intraoperative ultrasonography can readily demonstrate this distinction to aid in surgical decision making. Untethering alone in patients with tethered cord syndrome and cyst formation can reduce the cyst size and alleviate symptoms and signs of posttraumatic cystic myelopathy in the majority of these cases. Untethering procedures in which duraplasty is performed to expand the subarachnoid space may be a more physiologically effective way of treating tethered cord with associated syringomyelia.
Somatosensory evoked potential monitoring in anterior thoracic vertebrectomy
Authors: Deutsch Harel , Arginteanu Marc , Manhart Karen , Perin Noel , Camins Martin , Moore Frank , Steinberger A. Abe , Weisz Donald J
Published: May 2009

Object. Spine surgeons have used intraoperative cortical and subcortical somatosensory evoked potential (SSEP) monitoring to detect changes in spinal cord function when intraoperative procedures can be performed to prevent neurological deterioration. However, the reliability of SSEP monitoring as applied to anterior thoracic vertebral body resections has not been rigorously assessed.

Methods. The authors retrospectively reviewed hospital charts and operating room records obtained between August 1993 and December 1998 and found that SSEP monitoring was used in 44 surgical procedures involving an anterior approach for thoracic vertebral body resections.

There were no patients in whom SSEP changes did not return to baseline during the surgical procedure. Patients in four cases, despite their stable SSEP recordings throughout the procedure, were noted immediately postoperatively to have experienced significant neurological deterioration. The false-negative rate in SSEP monitoring was 9%. Sensitivity was determined to be 0%.

Conclusions. It is important to recognize high false-negative rates and low sensitivity of SSEP monitoring when it is used to record spinal cord function during anterior approaches for thoracic vertebrectomies. The insensitivity of SSEPs for motor deterioration during anterior thoracic vertebrectomies is likely due to the limitation of SSEPs, which monitor only posterior column function whereas motor paths are conveyed in the anterior and anterolateral spinal cord. The authors believe that SSEPs can not be relied on to detect reversible spinal damage during anterior thoracic vertebrectomies.
Treatment of severe retromastoid pain secondary to C1–2 arthrosis by using cervical fusion
Authors: HOLLY Langsto T. , Batzdorf Ulrich , Foley Kevin T.
Published: May 2009

Object. In this report the authors review their 5-year experience in the diagnosis and management of nine patients with severe retromastoid pain secondary to C1–2 arthrosis. Patients with symptomatic joints unresponsive to nonoperative therapy underwent cervical fusion procedures.

Methods. The mean age of the patients was 71 years, and the onset of prior symptoms ranged from 6 months to 18 years. All patients suffered similar discrete nonneuropathic pain without radicular symptoms ipsilateral to the diseased facet joint. Four patients experienced relief from pain with the use of nonoperative therapy. Five patients continued to experience intractable pain and underwent C1–2 fusion. The follow-up period ranged from 6 to 26 months. The cervical fusion procedure was successful in treating the retromastoid pain in all patients. In patients who underwent surgery, complete relief of pain was demonstrated in four and significantly reduced in the fifth.

Conclusions. The authors have drawn several conclusions. First, C1–2 arthrosis has a rather unique presentation and is a potential cause of upper posterior neck and head pain predominantly in elderly patients. Second, nonoperative management significantly improved the pain in nearly half of their patients and should be the first line of treatment. Last, C1–2 fusion was successful in treating the pain in patients in whom nonoperative management had failed to resolve symptoms.
Image-guided surgery: applications to the cervical and thoracic spine and a review of the first 120 procedures
Authors: Bolger Ciaran , Wigfield Crispin
Published: May 2009

Object. The authors undertook a study to demonstrate that frameless stereotaxy can be applied safely to the cervical and thoracic spine to minimize complications and associated morbidity.

Methods. A retrospective review of cases was conducted involving the use of an image-guidance system for the accurate placement of surgical implants or for resection of lesions within the cervical and thoracic spine. The outcome measures considered were neural injury, vascular injury, wound infection, surgical revision, and death.

Conclusions. Image-guidance systems are useful intraoperative tools that can be applied accurately to spinal surgery. In addition, such systems can be of great use in the preoperative planning of complex spinal surgery.
Coaxial double-lumen methylmethacrylate reconstruction in the anterior cervical and upper thoracic spine after tumor resection
Authors: Miller Daniel J. , Lang Frederick F. , Walsh Garrett L. , Abi-Said Dima , Wildrick David M. , Gokaslan Ziya L.
Published: May 2009

Object. A unique method of anterior spinal reconstruction after decompressive surgery was used to prevent methylmethacrylate—dural contact in cancer patients who underwent corpectomy. The purpose of this study was to assess the efficacy and stability of polymethylmethacrylate (PMMA) anterior surgical constructs in conjunction with anterior cervical plate stabilization (ACPS) in these patients.

Methods. Approximately 700 patients underwent spinal surgery at The University of Texas M. D. Anderson Cancer Center over a 4-year period. The authors conducted a retrospective outcome study for 29 of these patients who underwent anterior cervical or upper thoracic tumor resections while in the supine position. These patients were all treated using the coaxial, double-lumen, PMMA technique for anterior spinal reconstruction with subsequent ACPS. No postoperative external orthoses were used. Twenty-seven patients (93%) harbored metastatic spinal lesions and two (7%) harbored primary tumors. At 1 month postsurgery, significant improvement was seen in spinal axial pain (p < 0.001), radiculopathy (p < 0.00 1), gait (p = 0.008), and Frankel grade (p = 0.002). A total of nine patients (31%) underwent combined anterior—posterior 360° stabilization. Twenty-one patients (72%) experienced no complications. Complications related to instrumentation failure occurred in only two patients (7%). There were no cases in which the patients' status worsened, and there were no neurological complications or infections. The median Kaplan—Meier survival estimate for patients with spinal metastases was 9.5 months. At the end of the study, 13 patients (45%) had died and 16 (55%) were alive. Postoperative magnetic resonance images consistently demonstrated that the dura and PMMA in all patients remained separated.

Conclusions. The anterior, coaxial, double-lumen, PMMA reconstruction technique provides a simple means of spinal cord protection in patients in the supine position while undergoing surgery and offers excellent results in cancer patients who have undergone cervical vertebrectomy.
The apical ligament: anatomy and functional significance
Authors: Tubbs R. Shane , Grabb Paul , Spooner Alan , Wilson Wally , Oakes W. Jerry
Published: May 2009

Object. The authors conducted a study to describe the detailed anatomy of the apical ligament and to acknowledge or refute its historical description as a functionally significant contributor to craniocervical stability.

Methods. In 20 adult human cadavers measurements of the apical ligament were obtained, and its detailed anatomy was observed. Ranges of motion were also assessed to discern the function of the apical ligament.

Conclusions. Results of the study support the concept that the apical ligament is best described as a vestigial structure that offers no significant added stability to the craniocervical junction. In fact, this ligament was absent in 20% of the specimens examined. These data will aid physicians who frequently view images or manage clinical problems of the craniocervical junction because they may focus on other ligaments of this area and not the apical ligament.
Segmental cervical spine motion during orotracheal intubation of the intact and injured spine with and without external stabilization
Authors: Lennarson Peter J. , Smith Darin , Todd Michael M. , Carras Douglas , Sawin Paul D. , Brayton John , Sato Yutaka , Traynelis Vincent C.
Published: May 2009

Object. The purpose of this study was to establish a cadaveric model for evaluating cervical spine motion in both the intact and injured states and to examine the efficacy of commonly used stabilization techniques in limiting that motion.

Methods. Intubation was performed in fresh human cadavers with intact cervical spines, following the creation of a C4–5 posterior ligamentous injury. Movement of the cervical spine during direct laryngoscopy and intubation was recorded using video fluoroscopy and examined under the following conditions: 1) without external stabilization; 2) with manual in-line cervical immobilization; and 3) with Gardner—Wells traction. Subsequently, segmental motion of the occiput through C-5 (Oc—C5) was measured from digitized frames of the recorded video fluoroscopy.

The predominant motion, at all levels measured in the intact spine, was extension. The greatest degree of motion occurred at the atlantooccipital (Oc—C1) junction, followed by the C1–2 junction, with progressively less motion at each more caudal level. After posterior destabilization was induced, the predominant direction of motion at C4–5 changed from extension to flexion, but the degree of motion remained among the least of all levels measured. Traction limited but did not prevent motion at the Oc—C1 junction, but neither traction nor immobilization limited motion at the destabilized C4–5 level.

Conclusions. Cadaveric cervical spine motion accurately reflected previously reported motion in living, anesthetized patients. Traction was the most effective method of reducing motion at the occipitocervical junction, but none of the interventions significantly reduced movement at the subaxial site of injury. These findings should be considered when treating injured patients requiring orotracheal intubation.
Spontaneous resolution and recurrence of a Chiari I malformation and associated syringomyelia
Authors: Sun John C. L. , Steinbok Paul , Cochrane D. Douglas
Published: May 2009

✓ The spontaneous resolution of syringomyelia has been reported infrequently. In patients with Chiari I malformations, resolution of the syringomyelia has sometimes been associated with improvement of their malformation. The authors present a case of spontaneous resolution followed by recurrence of syringomyelia and a corresponding change in the Chiari malformation. This case is of interest in light of the theories postulated to explain spontaneous resolution of syringomyelia.
Myolipoma in a tethered cord
Authors: Brown Peter G. , Shaver Ellen G.
Published: May 2009

✓ The intradural myolipoma is a very rare tumor, consisting of fully differentiated striated muscle fibers mingled with fat. Only four previous cases have been identified. The authors present a case in which this tumor was associated with a symptomatic tethered spinal cord in an 18-year-old man.
Multiple hemangiomas (hemangiomatosis) of the cauda equina and spinal cord
Authors: Roncaroli Federico , Scheithauer Bernd W. , Deen H. Gordon
Published: May 2009

✓ A case of multiple hemangiomas of the cauda equina nerve roots, conus medullaris, and lower spinal cord is described. The 74-year-old male patient presented with a 9-month history of progressive bilateral leg weakness. He had a history of lymphoma at the age of 39 years and renal cell carcinoma in his early 40s. Neither disease was evident at the time of this presentation. A magnetic resonance image revealed multiple enhancing nodules in the cauda equina region as well as on the pial surface of the lower thoracic spinal cord and conus medullaris. The patient underwent an L2–3 laminectomy. Cauda equina nerve roots were found to be studded with numerous purple nodules, the largest measuring 6 to 8 mm. The nodules were adherent to nerve roots from which they could not be resected. Two lesions were histologically examined and found to be capillary hemangiomas. Twelve months into an uneventful postoperative course, the patient is neurologically unchanged. This unique case might represent a distinct form of hemangiomatosis confined to the cauda equina nerve roots and spinal cord.
Methylprednisolone for acute spinal cord injury: an inappropriate standard of care
Authors: Hurlbert R. John
Published: May 2009

Object. Since publication in 1990, results from the National Acute Spinal Cord Injury Study II (NASCIS II) trial have changed the way patients suffering an acute spinal cord injury (SCI) are treated. More recently, recommendations from NASCIS III are being adopted by institutions around the world. The purpose of this paper is to reevaluate carefully the results and conclusions of these studies to determine the role they should play in influencing decisions about care of the acutely spinal cord—injured patient.

Methods. Published results from NASCIS II and III were reviewed in the context of the original study design, including primary outcomes compared with post-hoc comparisons. Data were retroconverted from tabular form back to raw form to allow direct inspection of changes in treatment groups. These findings were further analyzed with respect to justification of practice standards.

Although well-designed and well-executed, both NASCIS II and III failed to demonstrate improvement in primary outcome measures as a result of the administration of methylprednisolone. Post-hoc comparisons, although interesting, did not provide compelling data to establish a new standard of care in the treatment of patients with acute SCI.

Conclusions. The use of methylprednisolone administration in the treatment of acute SCI is not proven as a standard of care, nor can it be considered a recommended treatment. Evidence of the drug's efficacy and impact is weak and may only represent random events. In the strictest sense, 24-hour administration of methylprednisolone must still be considered experimental for use in clinical SCI. Forty-eight-hour therapy is not recommended. These conclusions are important to consider in the design of future trials and in the medicolegal arena.
Spectrum of occipitoatlantoaxial injury in young children
Authors: Sun Peter P. , Poffenbarger Glen J. , Durham Susan , Zimmerman Robert A.
Published: May 2009

Object. Injuries of the occipitoatlantoaxial (Oc—C2) region are the predominant form of cervical injury in children younger than 10 years of age. Magnetic resonance (MR) imaging can be used to visualize directly the traumatic ligamentous and soft-tissue abnormalities of the Oc—C2 region. A retrospective review was undertaken to examine the spectrum of pediatric Oc—C2 injuries seen on MR imaging, their correlation with plain x-ray film and computerized tomography findings, and their clinical course.

Methods. Seventy-one consecutive children younger than 10 years of age underwent cervical MR imaging for evaluation of traumatic injury. Magnetic resonance imaging was used to document abnormalities in 23 children; 20 of these injuries involved the Oc—C2 region. Abnormalities in the Oc—C2 region included disruptions of the musculature, apical ligament, atlantooccipital joint(s), tectorial membrane, and spinal cord. A spectrum of injury with progressive involvement of these structures was seen, ranging from isolated muscular injury to the multiple soft-tissue and ligamentous disruptions with craniocervical dislocation. Involvement of the tectorial membrane was the critical threshold in the transition from stable to unstable injury. Analysis of plain x-ray films revealed that a novel interspinous C1–2:C2–3 ratio criteria of greater than or equal to 2.5 was predictive of tectorial membrane abnormalities on MR imaging, with 87% sensitivity and 100% specificity. In patients with tectorial membrane abnormalities who underwent immobilization alone, interim platybasia was demonstrated on follow-up MR images.

Conclusions. A progressive spectrum of distinct Oc—C2 injuries can occur in young children; the tectorial membrane is a critical stabilizing ligamentous structure in the Oc—C2 complex; and tectorial membrane abnormalities may be identified by a C1–2:C2–3 ratio of greater than or equal to 2.5.
New method for intraoperative determination of proper screw insertion or screw malposition
Authors: Açıkbaş Sabri Cem , Tuncer Mehmet Recai
Published: May 2009

Object. Inadequate imaging techniques may lead to misjudgment of screw positioning when applying transpedicular instrumentation; this can create potential risks of major vessel and nerve damage. In this article the authors present a new method to determine screw malpositioning intraoperatively.

Methods. The authors retrospectively evaluated pre- and postoperative plain radiographs of 97 spinal segments in which screws had been placed in 41 patients suffering from thoracolumbar injury who had previously undergone transpedicular screw fixation. They developed a new mathematical equation with which they determine the distance ratios of two screw tips in the same segment by comparing the distance between the pedicles on preoperative radiographs with those on postoperative radiographs. Subsequently, the results are compared with postoperative computerized tomography findings to determine which screws are in the correct position and which are penetrating the medial or lateral cortex of the pedicle. It was found that the ratio range of correctly placed screw tips was 46 ± 10% (mean ± standard deviation) in the thoracic region and 60 ± 9% in the lumbar region (ranges 43–50% and 57–63%, respectively, 95% confidence intervals). Higher ratios (higher percentages) than these values indicated extreme closeness of screw tips and therefore medial malpositioning. Lower ratios (lower percentages) indicated lateral malpositioning.

Conclusions. This proposed method may provide intraoperative determination of correct screw positioning or malpositioning. This method allows surgeons to replace the malpositioned screw, and, consequently, early resolution of neurovascular injuries is made possible. Additionally, repositioning of the screw correctly will avoid rigidity failure of the fixation device.
Surgical evaluation and management of lumbar synovial cysts: the Mayo Clinic experience
Authors: Lyons Mark K. , Atkinson John L. D. , Wharen Robert E. , Deen H. Gordon , Zimmerman Richard S. , Lemens Susan M.
Published: May 2009

Object. The authors report a retrospective analysis of 194 patients surgically treated at their institutions for symptomatic lumbar synovial cysts from January 1974 to January 1996.

Methods. Patient characteristics including age, sex, symptoms, signs, and preoperative neuroimaging studies were reviewed. Surgical procedures, complications, results, and pathological findings were correlated with preoperative assessment. One hundred ninety-four patients were surgically treated for symptomatic lumbar synovial cysts. Eighty percent were diagnosed and treated between 1987 and 1996. There were 100 men and 94 women with an average age of 66 years (range 28–94 years). The most common symptoms were painful radiculopathy (85%) and neurogenic single or multiroot claudication (44%). However, sensory loss (43%) and motor weakness (27%) were also presenting symptoms. Eleven percent of patients had undergone previous lumbar surgery prior to being referred to the Mayo Clinic. Preoperative neurological examination demonstrated motor weakness (40%), sensory loss (45%), reflex changes (57%), and variants of cauda equina syndrome (13%). In 19% of patients, normal neurological status was demonstrated. There was equal left/right-sided laterality, and eight patients presented with bilateral synovial cysts. The most commonly affected level was L4–5 (64%). All patients underwent laminectomy and resection of the cyst. Concomitant fusion was performed in 18 patients in whom clinical evidence of instability had been observed. However, subsequent fusion was required in only four patients who developed symptomatic spondylolisthesis. Surgery-related complications included cerebrospinal fluid leak (three patients), discitis (one patient), epidural hematoma (one patient), seroma (one patient), and deep vein thrombosis (one patient). One patient died 3 days after surgery of cardiac dysrhythmia. Follow-up data obtained for at least 6 months postoperatively were available in 147 patients. Of these, 134 (91%) reported good relief of their pain and 82% experienced improvement in their motor deficits.

Conclusions. Lumbar synovial cysts are a more common cause of lumbar radicular pain than previously thought. Surgical removal of the cyst is a safe and effective treatment for symptomatic relief in patients with lumbar synovial cysts. A concomitant fusion procedure may be performed in select cases. In this study, only a few patients developed symptomatic spinal instability requiring a second operation.
Protein kinase inhibition by fasudil hydrochloride promotes neurological recovery after spinal cord injury in rats
Authors: Hara Masahito , Takayasu Masakazu , Watanabe Kazuhiko , Noda Atsushi , Takagi Teruhide , Suzuki Yoshio , Yoshida Jun
Published: May 2009

Object. In Japan fasudil hydrochloride (HA1077), a protein kinase inhibitor, is widely administered to prevent vasospasm in patients after subarachnoid hemorrhage. The effects of fasudil on experimental spinal cord injury (SCI) were investigated and compared with those obtained using methylprednisolone.

Methods. Spinal cord contusion was induced in rats by applying an aneurysm clip extradurally to the spinal cord at T-3 for 1 minute. After injury three groups of rats were treated with intravenously administered saline (control), intraperitoneally administered fasudil (10 mg/kg), or intravenously administered methylprednisolone (four 30 mg/kg injections). Neurological recovery was evaluated periodically over 1 month by using a modified combined behavioral scale and histopathological examination. Leukocyte infiltration near the injury site was evaluated by measuring myeloperoxidase (MPO) activity at 24 hours. Spinal cord blood flow was measured at intervals up to 3 hours after injury by using laser Doppler flowmetry.

In rats in the fasudil-treated group significant improvement in modified combined behavioral score was demonstrated at each time point, whereas in the methylprednisolone-treated rats no beneficial effects were shown. In the fasudil-treated group, reduction of traumatic spinal cord damage was evident histologically in the caudal portion of the injured areas, and tissue MPO activity in tissue samples was reduced. Spinal cord blood flow was not significantly different between fasudiltreated and control group rats.

Conclusions. Fasudil hydrochloride showed promise of effectiveness in promoting neurological recovery after traumatic SCI. Possible mechanisms of this effect include protein kinase inhibition and decreased infiltration by neutrophils.
Spinal stability with anterior or posterior Ray threaded fusion cages
Authors: Hitchon Patrick W. , Goel Vijay , Rogge Thomas , Dooris Andrew , Drake John , Torner James
Published: May 2009

Object. The authors conducted a study to determine if the rigidity supplied to the spine by posterior placement of the Ray threaded fusion cage (TFC) is further enhanced by the placement of pedicle screws and, additionally, if bilateral anteriorly placed TFCs render the spine more rigid than a single anteriorly placed TFC.

Methods. Ten human cadaveric spinal specimens (L2—S1) were affixed within a testing frame. Loads of 1.5, 3, 4.5, and 6 Nm were applied to the spine in six degrees of freedom: flexion—extension, right and left lateral bending, and right and left axial rotation. Motion in an x, y, and z cartesian axis system was tracked using dual video cameras following light-emitting diodes attached to the spine and base plate. Load testing of the spines was performed in the intact mode, following which the spinal segments were randomized to receive anterior or posterior instrumentation. In five spine specimens we performed posterior discectomy, posterior lumbar interbody fusion (PLIF) with placment of femoral rings and pedicle screws, PLIF with bilateral TFCs, and bilateral TFCs with pedicle screws. Five other spines underwent anterior-approach discectomy, followed by implantation of a unilateral cage and bilateral cages. Load testing was performed after each step.

Conclusion. Spines in which PLIF with pedicle screws and TFCs with pedicle screws were placed were more rigid than after discectomy in all directions of motion except flexion. Anterior discectomy provided significantly (p ≤ 0.05) less stability in left and right axial rotation than the intact spines and following posterior discectomy. Following anterior implantation of bilateral TFCs, spines were significantly more rigid than after discectomy in all directions except extension.
Microendoscopic posterior cervical foraminotomy: a cadaveric model and clinical application for cervical radiculopathy
Authors: Burke Timothy G. , Caputy Anthony
Published: May 2009

Object. Cervical radiculopathy caused by either soft herniated disc material or foraminal stenosis is a common problem. Anterior and posterior surgical approaches are commonly used to decompress the nerve root. The authors undertook a study to establish the feasibility of performing a microendoscopic posterior approach for cervical foraminotomy in the clinical setting.

Methods. The authors performed an endoscopic posterior foraminotomy technique in which they used a rigid endoscope, in both a cadaver model and in three clinical cases, including one in which a multiple-level procedure was undertaken. Postoperatively, all patients returned to functional work status within 4 weeks. The mean length of hospitalization was 1.3 days.

Conclusions. The advantages to this technique include improved intraoperative visualization, a smaller incision, and significantly less postoperative discomfort compared with a traditional keyhole approach.
Neurocutaneous vascular hamartomas mimicking Cobb syndrome
Authors: Wakabayashi Yukihiro , Isono Mitsuo , Shimomura Tsuyoshi , Tajima Atushi , Terashi Hiroto , Asada Yuuji , Izumi Tatsuro , Hori Shigeaki
Published: May 2009

✓ The authors report the rare case of a patient with neurocutaneous vascular hamartomas mimicking Cobb syndrome. An 8-year-old boy was admitted to the authors' hospital with progressive urinary disturbance and upper back pain. Multiple skin nevi had been noted at the child's birth. Radiological examination revealed multiple cavernous angiomas in the spinal cord in the same metamere in which the skin nevi had been observed and also in the left cerebral hemisphere. His symptoms gradually improved without surgical intervention. Four years later he was readmitted because of a cerebral hemorrhage involving the left cerebral peduncle. Nonsurgical treatment was chosen because his symptoms promptly improved.

To the best of the authors' knowledge, this is the first case of multiple cavernous angiomas in the brain and spinal cord associated with skin nevi. The authors discuss this clinical entity and the significance of the disease.
Spinal intramedullary tuberculous lesion: medical management
Authors: Rao G. Prakash
Published: May 2009

✓ The author describes the successful medical management of intramedullary tuberculous lesions in four patients who received treatment between 1994 and 1997. The role of magnetic resonance imaging and the treatment protocol for intramedullary tuberculous lesions are also discussed.
Intramedullary spinal cord metastasis from gastric cancer
Authors: Taniura Seijiro , Tatebayashi Kyoko , Watanabe Kenji , Watanabe Takashi
Published: May 2009

✓ A case of intramedullary spinal cord metastasis from gastric cancer is reported. A 51-year-old woman presented with hemicord syndrome that had progressed within 1 month to tetraplegia. Despite total resection of the tumor, she died of disseminated intravascular coagulation and multiple organ failure. Examination of pathological findings demonstrated undifferentiated adenocarcinoma, and postoperative gastroendoscopic study revealed advanced gastric cancer. To the authors' knowledge this is the first case of intramedullary spinal cord metastasis from gastric cancer. The clinical characteristics of the disease are discussed.
Cervical epidural pseudotumor and multifocal fibrosclerosis
Authors: Gilliard Claude , Coene Beatrijs De , Lahdou Joseph Bou , Boutsen Yves , Noël Henri , Godfraind Catherine
Published: May 2009

✓ The authors present the case of a 45-year-old man suffering from progressive quadriplegia due to an expansive C3—T2 epidural mass. Neuropathological examination demonstrated pseudotumor tissue. The patient had had an orbital pseudotumor 5 years before admission, and other systemic manifestations of an idiopathic inflammatory disease were discovered. This case is extremely rare. Nine cases of multifocal fibrosclerosis with central nervous system involvement are described in the literature. To the authors' knowledge, this is the first description of a cervical epidural pseudotumor. Modern imaging has made the diagnosis of such an entity possible, and it is important for the neurosurgeon to consider this syndrome because the combination of surgery and systemic medical therapy can ensure a long-term survival with good quality of life.
Use of calcitonin for the treatment of an odontoid fracture
Authors: Darakchiev Borimir J. , Bulas Robert V. , Dunsker Stewart B.
Published: May 2009

✓ The authors report on the efficacy of nonsurgical treatment of an older patient with a fractured odontoid process. The patient, an 85-year-old woman, had multiple medical problems that put her at an increased surgery-related risk. Therefore, an alternative approach was elected, including immobilization with a Philadelphia collar and the provision of calcitonin nasal spray. Bone union and clinical recovery were achieved within 8 weeks of initiating the nasal calcitonin therapy (12 weeks postinjury). Considering the patient's age, comorbidities, and the severity of the fracture, the recovery period was unusually short. The authors believe that calcitonin played a pivotal role in the healing process of the fractured odontoid bone.

There is no question that the fusion in this patient could be unrelated to the medical therapy. This description of one patient, as well as the lack of a large randomized study, precludes any scientific conclusions. Nevertheless, the authors believe that the development of a successful fusion in this high-risk patient should be reported as an observation that merits confirmation and study.

The authors also discuss the physiological effects of calcitonin and the research and clinical experience with this hormone in different conditions affecting bone.
Evaluation of the 11th rib extrapleural—retroperitoneal approach to the thoracolumbar junction
Authors: Kim Miriam , Nolan Paul , Finkelstein Joel A.
Published: May 2009

Object. The 11th rib extrapleural—retroperitoneal approach offers an alternative means for access to the thoracolumbar junction. It provides excellent operative exposure without the need to transgress the diaphragm, resulting in less morbidity and reduced risk of pulmonary complications. This approach, however, has been dismissed by many surgeons offering the unsubstantiated criticism that it affords limited access. Thus far, only technical descriptions of the operative procedure are available in the literature, without documentation of the clinical outcomes of these patients.

In the current study the authors describe the 11th rib extrapleural—retroperitoneal approach to the thoracolumbar junction, and they evaluate the associated early and late morbidity in these patients.

Methods. From September 1996 to August 1999, the authors collected prospective data of consecutive patients who underwent surgery for a variety of pathological conditions of the thoracolumbar junction via this approach. In 26 consecutive patients requiring an anterior spinal procedure, lesions located between T-10 and T-11 were studied and followed for a mean period of 17 months (range 1–36 months). There were 13 men and 13 women whose mean age was 47 years (range 16–80 years), with the following pathological entities: trauma (13 cases), neoplasm (six cases), infection (two cases), and deformity (five cases). There were no cases of neurological deterioration. There were no significant pulmonary complications, and only one patient required insertion of a postoperative chest tube.

Conclusions. The 11th rib extrapleural—retroperitoneal approach was successfully used to treat patients with a variety of lesions in the thoracolumbar junction and was associated with little morbidity. The authors believe that previous criticism suggesting that this approach provides only limited access is unsubstantiated.
Radical excision of intramedullary spinal cord tumors: surgical morbidity and long-term follow-up evaluation in 164 children and young adults
Authors: Constantini Shlomi , Miller Douglas C. , Allen Jeffrey C. , Rorke Lucy B. , Freed Diana , Epstein Fred J.
Published: May 2009

Object. The majority of intramedullary spinal cord tumors (IMSCT) in children and young adults are low-grade gliomas. Radical resection of similar tumors in the cerebral hemisphere or cerebellum is usually curative; however, the conventional management for IMSCTs remains partial resection followed by radiotherapy because of the concern for surgical morbidity. Nevertheless, radical resection of IMSCTs without routine adjuvant treatment has been the rule at our institution since 1980. In an attempt to resolve this controversy, the long-term morbidity and survival in a large series of children have been retrospectively reviewed.

Methods. The database records and current status of 164 patients 21 years of age and younger in whom an IMSCT was resected were reviewed. A gross-total resection (> 95%) was achieved in 76.8% of the surgical procedures. Subtotal resections (80–95%) were performed in 20.1%. The majority of patients (79.3%) had histologically low-grade lesions.

There were no deaths due to surgery. When comparing the preoperative and 3-month postoperative functional grades, 60.4% stayed the same, 15.8% improved, and 23.8% deteriorated. Only 13 patients deteriorated by more than one functional grade. Patients with either no deficits or only mild deficits before surgery were rarely injured by the procedure, reinforcing the importance of early diagnosis and treatment.

The major determinant of long-term patient survival was histological composition of the tumor. The 5-year progression-free survival rate was 78% for patients with low-grade gliomas and 30% for those with high-grade gliomas. Patients in whom an IMSCT was only partially resected (< 80%) fared significantly worse.

Conclusions. The long-term survival and quality of life for patients with low-grade gliomas treated by radical resection alone is comparable or superior to minimal resection and radiotherapy. The optimum therapy for patients with high-grade gliomas is yet to be determined.
Treatment of Down syndrome—associated craniovertebral junction abnormalities
Authors: Taggard Derek A. , Menezes Arnold H. , Ryken Timothy C.
Published: May 2009

Object. Operative intervention for craniovertebral junction (CVJ) instability in patients with Down syndrome has become controversial, with reports of a low incidence of associated neurological dysfunction and high surgical morbidity rates. The authors analyzed their experience in light of these poor results and attempted to evaluate differences in management.

Methods. Medical and radiographic records of 36 consecutive patients with Down syndrome and CVJ abnormalities were reviewed. The most common clinical complaints included neck pain (15 patients) and torticollis (12 patients). Cervicomedullary compression was associated with ataxia and progressive weakness. Hyperreflexia was documented in a majority of patients (24 cases), and 13 patients suffered from varying degrees of quadriparesis. Upper respiratory tract infection precipitated the presentation in five patients. Four patients suffered acute neurological insults after a minor fall and two after receiving a general anesthetic agent.

Atlantoaxial instability was the most common radiographically observed abnormality (23 patients), with a rotary component present in 14 patients. Occipitoatlantal instability was also frequently observed (16 patients) and was coexistent with atlantoaxial dislocation in 15 patients. Twenty individuals had bone anomalies, the most frequent of which was os odontoideum (12 patients) followed by atlantal arch hypoplasia and bifid anterior or posterior arches (eight patients).

Twenty-seven patients underwent surgical procedures without subsequent neurological deterioration, and a 96% fusion rate was observed. In five of 11 patients basilar invagination was irreducible and required transoral decompression. Overall, 24 patients enjoyed good or excellent outcomes.

Conclusions. The results of this series highlight the clinicopathological characteristics of CVJ instability in patients with Down syndrome and suggest that satisfactory outcomes can be achieved with low surgical morbidity rates.