The effect of steroids on the incidence of gastrointestinal hemorrhage after spinal cord injury: a case-controlled study.

STUDY DESIGN: Retrospective case-controlled study. OBJECTIVES: To understand the incidence of gastrointestinal hemorrhage (GIH) and subsequent mortality rate associated with steroid use after acute spinal cord injury (SCI). SETTING: Miami, Florida, USA. METHODS: This case-controlled study investigates two sequential study groups with SCI treated by a single surgeon in a level I trauma center. The first study cohort (1997-2005) received steroids according to the NASCIS II protocol and the second (2005-2012) received no steroid treatment. The groups were comparable with respect to age, sex, severity and level of injury (43 vs 45 years old/3:1 male-female/AIS scale %-43.5 vs 41.7 A, 10.6 vs 11.1 B, 20.3 vs 13.4 C, 25.4 vs 33.5 D/64.3 vs 73.8% cervical, 35.6 vs 25.7% thoracic and lumbar). The incidence and mortality from GIH were the primary outcome measures. RESULTS: A total of 350 patients were evaluated during the study period. The incidence of GIH in the SCI group receiving steroids was 6/216 (2.77%) with 2 mortalities (33.3%). No gastrointestinal (GI) complications were noted in the 134 patients that did not receive any steroids (P=0.086). All GIH cases in the steroid group were in cervical SCI patients-6/139 (4.32%; P=0.043). Average time to onset of GIH was 16 days. CONCLUSION: The use of steroids in acute SCI appears to be a key risk factor in increasing the incidence of clinically overt GI complications with a subsequent high mortality rate, particularly in patients with cervical SCI.

Systemic hypothermia in acute cervical spinal cord injury: a case-controlled study.

INTRODUCTION: Systemic hypothermia remains a promising neuroprotective strategy. There has been recent interest in its use in patients with spinal cord injury (SCI). In this article, we describe our extended single center experience using intravascular hypothermia for the treatment of cervical SCI. METHODS: Thirty-five acute cervical SCI patients received modest (33 °C) intravascular hypothermia for 48 h. Neurological outcome was assessed by the International Standards for Neurological Classification of Spinal Cord Injury scale (ISNCSCI) developed by the American Spinal Injury Association. Local and systemic complications were recorded. RESULTS: All patients were complete ISNCSCI A on admission, but four converted to ISNCSCI B in <24 h post injury. Hypothermia was delivered in 5.76 (±0.45) hours from injury if we exclude four cases with delayed admission (>18 h). Fifteen of total 35 patients (43%) improved at least one ISNCSCI grade at latest follow up 10.07 (±1.03) months. Even excluding those patients who converted from ISNCSCI A within 24 h, 35.5% (11 out of 31) improved at least one ISNCSCI grade. Both retrospective (n=14) and prospective (n=21) groups revealed similar number of respiratory complications. The overall risk of any thromboembolic complication was 14.2%. CONCLUSION: The results are promising in terms of safety and improvement in neurological outcome. To date, the study represents the largest study cohort of cervical SCI patients treated by modest hypothermia. A multi-center, randomized study is needed to determine if systemic hypothermia should be a part of SCI patients' treatment for whom few options exist.

Characterization of the technique involved in isolating Schwann cells from adult human peripheral nerve.

Only recently has it been possible to isolate large quantities of adult derived Schwann cells (SCs) from peripheral nerves in cell culture. These techniques can be easily applied to the isolation of human SCs. We evaluated the influence of donor age and length of explant culture time on the purity of the human SC preparations obtained from a large number (n = 35) of live organ donors ranging in age from 1 to 63 years. The average SC purity from all donors was 92.7 +/- 2.73% and did not appear to be influenced by donor age or duration of culture time in excess of 1 week. Myelin debris was a prominent feature of human SCs prepared in culture and could be detected within histological sections of cultured peripheral nerve segments as well as within human SCs obtained from enzymatic dissociation of the peripheral nerves. This report supports the reproducibility of the techniques involved in isolating human SCs from peripheral nerve from a large series of donors and addresses the mechanism in which a period of cell culture permits the isolation of large quantities of adult human SCs.

Treatment of a retroperitoneal lymphocele after lumbar fusion surgery with intralesional povidone iodine: technical case report.

OBJECTIVE AND IMPORTANCE: This case report illustrates an uncommon complication from the retroperitoneal exposure of the lumbar spine. The diagnosis and management of a retroperitoneal lymphocele is presented. The lymphocele was treated with intralesional povidone iodine (Betadine; Purdue-Frederick, Norwalk, CT), which eradicated the lesion and provided symptomatic relief to the patient. CLINICAL PRESENTATION: A young woman developed an iatrogenic, rapidly progressive spondylolisthesis after having undergone three previous lumbar surgeries for radiculopathy at the L5-S1 level. INTERVENTION: A back-front-back approach was used for operative reduction and fusion of the spondylolisthesis. The patient's postoperative course was complicated by a retroperitoneal lymphocele. She presented with symptoms of urinary urgency and incontinence. The lymphocele was successfully treated with repeated drainage and sclerosis with povidone iodine. The patient ultimately developed a solid fusion, and her pain resolved. CONCLUSION: A retroperitoneal lymphocele is an uncommon complication caused by the surgical exposure of the lumbar spine when a ventral approach is used. In this case, it was diagnosed and treated without further surgical intervention.

Tuberculosis of the axis in a patient with systemic sarcoidosis: technique of posterior open biopsy of the dens: case report.

OBJECTIVE AND IMPORTANCE: This case report illustrates the importance of obtaining tissue from a destructive lesion of the dens in a patient with systemic sarcoidosis. Although sarcoidosis can involve the axial skeleton, tissue obtained at the time of C1-C2 fusion demonstrated unsuspected pathological features, which dramatically altered the subsequent medical treatment. The technique of open posterior biopsy of the dens is illustrated, and the advantages of the approach are discussed. CLINICAL PRESENTATION: A 40-year-old woman with systemic sarcoidosis developed neck pain and atlantoaxial instability. Imaging revealed multiple thoracic and cervical vertebral abnormalities, including a destructive enhancing lesion involving the base of the dens. INTERVENTION: At the time of posterior C1-C2 fusion, we elected to perform an open biopsy of the base of the dens. A 16-gauge biopsy needle was introduced along the medial portion of the left C2 pars, aiming medially toward the base of the odontoid process. This procedure was performed under direct observation, with fluoroscopic guidance. The biopsy specimen contained caseating granulomas, and cultures were positive for Mycobacterium tuberculosis. CONCLUSION: The unusual presentation, the technique, and the importance of obtaining tissue to confirm the diagnosis of tuberculous involvement of the dens are emphasized. The relationship between sarcoidosis and tuberculosis reported in the literature is reviewed. In the current case, cell wall-positive tuberculous bacteria were cultured, confirming the presence of two separate diseases in the same patient.

Venous thromboembolism after brain tumor surgery: a retrospective review.

We retrospectively reviewed the incidence rate of clinical postoperative deep vein thrombosis and/or pulmonary embolism in 1703 patients undergoing initial craniotomy for meningioma, glioma, or cerebral metastasis. The incidence rate of clinical thromboembolic complications was 1.59% for all tumor groups within the first 4 weeks of surgery. Patients undergoing surgery for meningiomas had a statistically significant increased risk of thromboembolism despite fewer overall perioperative risk factors, when compared with the other tumor groups. The tumor-specific incidence rates of deep vein thrombosis and/or pulmonary embolism for meningioma, glioma, and metastasis were 3.09%, 0.97%, and 1.03%, respectively. Whether this difference was a result of increased surgical time or an inherent property of meningiomas could not be ascertained.

Clinical syndromes associated with disproportionate weakness of the upper versus the lower extremities after cervical spinal cord injury.

Patients with cervical spinal cord injuries who present with weakness or paralysis of the hands and arms with relative preservation of lower extremity strengths are often categorized as having two clinical syndromes, cruciate paralysis and acute central cervical spinal cord injury. The explanation for the pathophysiological findings of the dissociated strength in the upper versus the lower extremities has relied on the assumption that there is a localized injury within a somatotopically organized corticospinal tract. This article summarizes the evidence that there is no somatotopic organization within the corticospinal tract in the medulla or cervical spinal cord in primates. An alternative hypothesis for these two syndromes is presented and is based on evidence that has demonstrated that the corticospinal tract in primates is critical for hand function but not for locomotion. Other prevailing theories are reviewed. Thus, we propose that a syndrome consisting of relatively greater hand and arm weakness compared with leg weakness can occur after an injury to the corticospinal tracts in the medulla or the cervical cord. The proposed mechanism, based on the function of the corticospinal tract, unifies a spectrum of injuries of the lower medulla and cervical spinal cord, which produce similar clinical syndromes (cruciate paralysis and acute central cervical spinal cord injury).

Computer-assisted fluoroscopic targeting system for pedicle screw insertion.

OBJECTIVE: Biplanar fluoroscopic imaging linked to a computer-driven mechanical end-effector is under development as a targeting system for spinal surgery. This technology has the potential to enhance standard intraoperative fluoroscopic information for localization of the pedicle entry point and trajectory, and it may be an effective alternative to the computed tomography-based image-guided system (IGS) in pedicle screw placement. A preclinical study to assess the accuracy and time efficiency of this system versus a conventional IGS was conducted. METHODS: Pedicle screw placement was performed in six cadavers from T1 to S1 levels using the ViewPoint IGS (Picker International, Inc., Cleveland, OH) on one side versus the Fluorotactic guidance system (Z-Kat, Inc., Miami, FL) on the other side. Of 216 possible pedicles, 208 were instrumented; 8 pedicle diameters were too small or were not adequately imaged. Postinsertion, each pedicle was assessed for the presence and location of cortical perforation using computed tomographic scanning and direct visualization. RESULTS: The number of successful screw placements was 89 (87.3%) of 102 for IGS and 87 (82.1 %) of 106 for the Fluorotactic guidance system, respectively. The mean time to register and operate on one level using the Fluorotactic guidance system was 14:34 minutes (minutes:seconds), compared with 6:50 minutes using the IGS. The average fluoroscope time was 4.6 seconds per pedicle. CONCLUSION: Our data indicate that this first-generation fluoroscopy-based targeting system can significantly assist the surgeon in pedicle screw placement. The overall accuracy is comparable to an IGS, especially in the region of T9-L5. A second-generation system with a faster end-effector and user-friendly interface should significantly reduce the operating and fluoroscope time.

Spinal hemangioblastoma, syrinx, and hydrocephalus in a two-year-old child.

A two-year-old child presented with an acute inability to bear weight. Radiological investigation revealed a large cervicothoracolumbar syrinx of no known cause. During investigation, acute communicating hydrocephalus developed, which required a shunt. At surgery, a small thoracic spinal cord hemangioblastoma was discovered and excised. Complete recovery with collapse of the syrinx followed. The clinical features of this rare childhood tumor and its associated effects are discussed.

Subacute posttraumatic ascending myelopathy after spinal cord injury. Report of three cases.

Subacute posttraumatic ascending myelopathy is a rare disorder, unrelated to syrinx formation or mechanical instability, that may gradually emerge within the first 1 to 2 weeks after a spinal cord injury. The authors describe three patients with this syndrome and discuss its possible causes as well as its clinical presentation, imaging characteristics, treatment, and patient prognosis.

Management of postoperative infections after spinal instrumentation.

The authors retrospectively reviewed 452 consecutively treated patients who underwent a spinal instrumentation procedure at a single institution to establish which patients and which surgical approaches might be associated with an increased risk of developing deep wound infections and to determine the efficacy with which the institution's current treatment strategy eradicates these infections. Wound infections occurred in 17 patients (10 men and seven women) with spinal instrumentation (incidence 3.8%). All infections occurred after posterior spinal instrumentation procedures (7.2%); there were no infections after anterior instrumentation procedures regardless of the level. Each patient was assigned an infection risk factor (RF) score depending on the number of RFs identified in an individual patient preoperatively. The mean RF score of patients who developed infections was 2.18, whereas the mean RF score for a procedure-matched, infection-free control group was 0.71. The mean number of days from surgery to clinical presentation was 27.6 days (range 4-120 days), and the mean increase in hospitalization time for the subset of patients who developed infections was 16.6 days. The most common organism isolated from wound cultures was Staphylococcus aureus (nine of 17 cases). Of the 17 patients, five had infections involving multiple organisms. All patients were infection free at a minimum of 8 months follow-up review. The current treatment regimen advocated at this institution consists of operative debridement of the infected wound, a course of intravenous followed by oral antibiotic medications, insertion of an antibiotic-containing irrigation-suction system for a mean of 5 days, and maintenance of the instrumentation system within the infected wound.

Apoptosis after traumatic human spinal cord injury.

OBJECT: Apoptosis is a form of programmed cell death seen in a variety of developmental and disease states, including traumatic injuries. The main objective of this study was to determine whether apoptosis is observed after human spinal cord injury (SCI). The spatial and temporal expression of apoptotic cells as well as the nature of the cells involved in programmed cell death were also investigated. METHODS: The authors examined the spinal cords of 15 patients who died between 3 hours and 2 months after a traumatic SCI. Apoptotic cells were found at the edges of the lesion epicenter and in the adjacent white matter, particularly in the ascending tracts, by using histological (cresyl violet, hematoxylin and eosin) and nuclear staining (Hoechst 33342). The presence of apoptotic cells was supported by staining with the terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick-end labeling technique and confirmed by immunostaining for the processed form of caspase-3 (CPP-32), a member of the interleukin-1beta-converting enzyme/Caenorhabditis elegans D 3 (ICE/CED-3) family of proteases that plays an essential role in programmed cell death. Apoptosis in this series of human SCIs was a prominent pathological finding in 14 of the 15 spinal cords examined when compared with five uninjured control spinal cords. To determine the type of cells undergoing apoptosis, the authors immunostained specimens with a variety of antibodies, including glial fibrillary acidic protein, 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase), and CD45/68. Oligodendrocytes stained with CNPase and a number of apoptotic nuclei colocalized with positive staining for this antibody. CONCLUSIONS: These results support the hypothesis that apoptosis occurs in human SCIs and is accompanied by the activation of caspase-3 of the cysteine protease family. This mechanism of cell death contributes to the secondary injury processes seen after human SCI and may have important clinical implications for the further development of protease inhibitors to prevent programmed cell death.

Clival chordoma presenting with acute brain stem hemorrhage.

The authors present a case of a 29-year-old man who developed rapidly progressive cranial nerve palsies and a right hemiparesis secondary to a pontine hemorrhage. The rare but correct diagnosis of a clival chordoma which had invaded the brain stem and subsequently hemorrhaged was based on computed tomography and magnetic resonance imaging. The diagnosis was confirmed at surgery when the patient underwent a successful operative decompression of tumor and clot from the pons via a sub-occipital craniotomy. This represents the first case of a clival chordoma to hemorrhage into the brain stem, which was diagnosed preoperatively and the patient survived.

Management of posttraumatic syringomyelia using an expansile duraplasty. A case report.

STUDY DESIGN: A patient in whom posttraumatic syringomyelia developed 34 years after an L2 fracture is reported. OBJECTIVES: To review the pathophysiology and current management modalities for posttraumatic syringomyelia. The delayed presentation and management rationale of this case are emphasized. SUMMARY OF BACKGROUND DATA: This case represents the most delayed onset of symptoms from a posttraumatic syrinx reported in the literature. Although lysis of arachnoid adhesions and expansile duraplasty to recreate the subarachnoid space have been described for nonshuntable syrinxes, this form of management was used as the primary management modality in this case. METHODS: A posttraumatic syrinx was managed by lysis of the arachnoid adhesions, fenestration of the cyst, and an expansile duraplasty. RESULTS: After surgery, the patient's symptoms improved, and magnetic resonance imaging showed a decrease in the size of the syrinx. CONCLUSION: Posttraumatic syringomyelia represents one of the few surgically remediable presentations of spinal cord injury. Consequently, it is necessary to continuously develop and monitor new management options for this disease. In the case reported here, the syrinx was treated successfully without the implanting a drainage tube.

Surgery for lumbar disc herniation during pregnancy.

STUDY DESIGN: The case reports of three pregnant patients with lumbar disc herniation causing cauda equina syndrome or severe neurologic deficits are presented to illustrate that disc surgery during gestation is a safe method of management. OBJECTIVE: To emphasize the importance of recognizing and definitively treating lumbar disc displacement causing neurologic deficits during pregnancy. SUMMARY OF BACKGROUND DATA: The advent of magnetic resonance imaging and modern surgical techniques for treatment of lumbar disc displacement allows safe management of this condition at any stage of gestation. A review of the literature on the risks of nonobstetric surgery and the risks of delaying disc surgery until delivery shows that operating at any stage during gestation for severe neurologic deficit secondary to lumbar disc displacement is justified. METHODS: A review of the literature on the use of magnetic resonance imaging scan and nonobstetric surgery during pregnancy was performed. Three case reports of the authors' patients who had lumbar disc displacement with cauda equina syndrome or severe neurologic deficit are presented. Patients were placed prone on a four-poster frame, and an epidural anesthetic agent was administered. A one-level hemilaminectomy, partial facetectomy, and disc excision were performed in all three cases. RESULTS: The methods used for diagnosis and surgical treatment of three patients with disc herniation during pregnancy resulted in a satisfactory outcome for both mother and child. The medical literature supports surgical intervention in pregnant patients with cauda equina syndrome and severe and/or progressive neurologic deficit(s) from lumbar disc displacement at any state of gestation. CONCLUSION: Although extremely rare, cauda equina syndrome and severe and/or progressive neurologic deficit caused by lumbar disc displacement can occur during pregnancy. The prevalence of symptomatic lumbar disc herniation during pregnancy may be on the increase because of the increasing age of patients who are becoming pregnant. These cases showed, and the literature confirms, that pregnancy at any stage is no contraindication to magnetic resonance imaging scan, epidural and/or general anesthesia, and surgical disc excision.

The radiographic and imaging characteristics of porous tantalum implants within the human cervical spine.

STUDY DESIGN: Seven cadaveric cervical spines were implanted with a porous tantalum spacer and a titanium alloy spacer, and their radiographic and imaging characteristics were evaluated. OBJECTIVE: To determine the radiographic characteristics of porous tantalum and titanium implants used as spacers in the cervical spine. SUMMARY OF BACKGROUND DATA: Anterior decompressive surgery of the disc space or the vertebral body creates a defect that frequently is repaired with autologous bone grafts to promote spinal fusion. Donor site morbidity, insufficient donor material, and additional surgical time have spurred the development of biomaterials to replace or supplement existing spinal reconstruction techniques. Although the promotion of a solid bony fusion is critical, the implanted biomaterial should be compatible with modern imaging techniques, should allow visualization of the spinal canal and neural foramina, and should permit radiographic assessment of bony ingrowth. METHODS: Cadaveric spines containing the implants were imaged with plain radiography, computerized tomography, and magnetic resonance imaging. The image distortion produced by the implants was determined qualitatively and quantitatively. RESULTS: The tantalum and titanium spacers were opaque on plain radiographic films. On computed tomographic scans, more streak artifact was associated with the tantalum implants than with the titanium. On magnetic resonance imaging, the porous tantalum implant demonstrated less artifact than did the titanium spacer on T1- and T2-weighted spin echo and on T2*-weighted gradient-echo magnetic resonance images. Overall, the tantalum implant produced less artifact on magnetic resonance imaging than did the titanium spacer and therefore allowed for better visualization of the surrounding bony and neural structures. CONCLUSION: The material properties of titanium and porous tantalum cervical interbody implants contribute to their differential appearance in different imaging methods. The titanium implant appears to image best with computed tomography, whereas the porous tantalum implant produces less artifact than does the titanium implant on several magnetic resonance imaging sequences.

Contemporary management of adult intramedullary spinal tumors-pathology and neurological outcomes related to surgical resection.

STUDY DESIGN: Retrospective chart review and review of the recent literature. OBJECTIVES: To present our experience, over an 8-year period, with aggressive microsurgical resection of intramedullary spinal tumors in adults focusing on histology, microsurgical techniques, short-term neurological outcomes, complication avoidance and dorsal column dysfunction (DCD). SETTING: University of Miami/Jackson Memorial Medical Center Miami, FL, USA. METHODS: We conducted a retrospective review of a series of adult patients with intramedullary spinal tumors treated with microsurgical excision at the University of Miami/Jackson Memorial Medical Center between January 1997 and September 2005. RESULTS: Histologic analysis revealed a predominance of ependymomas (50%) with astrocytomas only comprising 12.5% of the tumors. We found no significant difference in pre- and postoperative McCormick grades. Although patients did not manifest significant motor weakness postoperatively as a result of surgery, 43.6% of patients exhibited the signs and symptoms of DCD, resulting in significant postoperative morbidity. CONCLUSION: We present a contemporary adult series of intramedullary spinal tumors. The most significant postoperative morbidity experienced by patients was DCD. The neurosurgeon should recognize the impact of these symptoms, prepare the patient and his/her family for the possibility of DCD, and minimize dorsal column manipulation in an attempt to decrease its prevalence.

Expression of neurotrimin in the normal and injured adult human spinal cord.

STUDY DESIGN: Neurotrimin (Ntm) is a member of the family of neural cell adhesion molecules. Its expression pattern suggests that Ntm promotes axonal fasciculation, guides nerve fibers to specific targets and stabilizes synapses as it accumulates coincident with synaptogenesis. Strong labeling of Ntm was observed in motor and sensory areas of the postnatal rat cortex. It is not known whether Ntm is present in adult human spinal cord (SC). In the present study, a monoclonal antibody specific for Ntm (1B1), is applied to the first study of the expression of Ntm in normal and injured adult human SC. OBJECTIVE: (1) To investigate the expression pattern of Ntm in adult normal human SC, and (2) to observe the changes of Ntm expression after SC injury and compare the differences between normal and injured adult human SC. METHODS: Human SC tissue was obtained from necropsies of patients with (n=5) and without (n=4) SC injury. The 1B1 Ntm monoclonal antibody was used for immunohistochemical staining on paraffin embedded sections with an ABC kit. RESULTS: (1) In total, 12 slides were analyzed for each group from both cervical and thoracic levels. Motor neurons and Clarke's neurons and glial-like cells were mild to moderately positive in all uninjured SC specimens. (2) In injured SC, no staining was observed in the injury epicenter between two and three levels proximally and distally, but was detected five levels away. (3) In patients older than 67 years of age, Ntm-positive inclusions were present in the white matter of the SC with or without injury. (4) Some meningeal cells were strongly Ntm-positive, especially in the uninjured human SC. CONCLUSION: Ntm is expressed by motor and Clarke's neurons and glial cells in uninjured human SC. The downregulation of Ntm in the injured SC suggests that its expression is regulated by afferent input.

High-dose methylprednisolone may cause myopathy in acute spinal cord injury patients.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: Although Bracken et al have demonstrated a significant neuroprotective effect of high-dose intravenous (i.v.) methylprednisolone (MP) within 8 h post spinal cord injury (SCI), this practice has recently been challenged. We hypothesized it is possible that acute corticosteroid myopathy (ACM) may occur secondary to the MP. This pilot study was performed to test this hypothesis. SETTING: University of Miami School of Medicine/Jackson Memorial Hospital, Miami VA Medical Center, FL, USA. METHODS: Subjects included five nonpenetrating traumatic SCI patients, who received 24 h MP according to National Acute Spinal Cord Injury Studies (NASCIS) protocol, and three traumatic patients who suffered SCI and did not receive MP. Muscle biopsies and electromyography (EMG) were performed to determine if myopathic changes existed in these patients. RESULTS: Muscle biopsies from the SCI patients who received 24 h of MP showed muscle damage consistent with ACM in four out of five cases. EMG studies demonstrated myopathic changes in the MP-treated patients. In the three patients who had SCI but did not receive MP, muscle biopsies were normal and EMGs did not reveal evidence of myopathy. CONCLUSION: Our data suggest that MP in the dose recommended by the NASCIS may cause ACM. If this is true, part of the improvement of neurological recovery showed in NASCIS may be only a recording of the natural recovery of ACM, instead of any protection that MP offers to the injured spinal cord.