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.

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.

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.

Multi-tiered treatment of pressure sores in two cynomologous macaques (Macaca fascicularis).

Successful treatment of one Grade IlI and two Grade IV pressure sores on two female Macaca fascicularis, subsequent to a T11 hemilaminectomy and left spinal cord hemisection, was achieved through a combined strategy of wound care, diet, and husbandry. Wound care consisted of early and thorough debridement of all necrotic tissue, initial twice daily cleaning with an iodine scrub and application of a multi-ingredient ointment. Tissue hydrolyzer, a drying agent, vitamin E, ground selenium, and topical antibiotics were applied to the wound during the respective 45- and 46-day courses of treatment. Oral antibiotics were administered; vitamins C and E, and selenium were increased in the diet. No infection occurred and both animals recovered fully to complete the study. Importantly, pressure sores in subsequent study animals were prevented by post-operative padding of the perch with towel-covered foam and placement of a wheelchair cushion on the floor of the cage.

The management of traumatic cervical bilateral facet fracture-dislocations with unicortical anterior plates.

The goal of this study was to evaluate single-level anterior cervical discectomy and stabilization for bilateral facet fracture dislocations using bone graft and anterior titanium plates with unicortical screw fixation in the clinical setting. We conducted a retrospective review during a consecutive 6-year period of patients treated in a single institution for traumatic single-level cervical bilateral facet fracture-dislocation. All fracture-dislocations that could be aligned with traction were subsequently stabilized using an anterior cervical discectomy with bone graft and titanium unicortical locking plates. All patients were examined after operation for radiographic evidence of healing and neurologic outcome. Twenty-two patients (M:F ratio, 16:6; average age, 47.7 years) underwent an anterior cervical discectomy and stabilization with either an allograft (n = 12) or an autograft (n = 10) and a titanium unicortical locking plate. Most patients had sustained a spinal cord injury (87%) or a radicular injury (9%). The average follow-up was 32 months, with a minimum follow-up of 1 year (range, 13 to 77 months). There was one instrumentation-related failure, but all 22 patients ultimately had evidence of stability at the instrumented level on the final follow-up examination. Anterior fixation with unicortical cervical locking plates as a single procedure offers an excellent surgical alternative in the management of many cervical bilateral facet fracture dislocations in patients who can be reduced preoperatively.

A histopathological analysis of the human cervical spinal cord in patients with acute traumatic central cord syndrome.

STUDY DESIGN: We have applied conventional histochemical and morphometric techniques to study the changes within the human spinal 'hand' motor neuron pool after spinal cord injury in patients who presented with acute traumatic central cord syndrome (ATCCS). OBJECTIVE: To determine whether a reduction of large alpha motor neurons at the C7, C8 and T1 spinal cord levels underlies the mechanism which causes hand dysfunction seen in patients with (ATCCS). BACKGROUND: The etiology of upper extremity weakness in ATCCS is debated and injury and/or degeneration of motor neurons within the central gray matter of the cervical enlargement has been advanced as one potential etiology of hand weakness. METHODS: The spinal cords of five individuals with documented clinical evidence of ATCCS and three age-matched controls were obtained. The ATCCS spinal cords were divided into acute/sub-acute (two cases) and chronic (three cases) groups depending on the time to death after their injury; the chronic group was further subdivided according to the epicenter of injury. We counted the motor neurons using light microscopy in 10 randomly selected axial sections at the C7, C8 and T1 spinal cord levels for each group. We also analyzed the lateral and ventral corticospinal tracts (CST) in all groups for evidence of Wallerian degeneration and compared them to controls. RESULTS: A primary injury to the lateral CST was present in each case of ATCCS with evidence of Wallerian degeneration distal to the epicenter of injury. There was minimal Wallerian degeneration within the ventral corticospinal tracts. In the chronic low cervical injury group, there was a decrease in motor neurons supplying hand musculature relative to the other injury groups where the motor neurons sampled at the time of death were not reduced in number when compared to the control group. CONCLUSIONS: We hypothesize that hand dysfunction in ATCCS can be observed after spinal cord injury without any apparent loss in the number of motor neurons supplying the hand musculature as seen in our acute/sub-acute (n=2) and our chronic high injury (n=1) groups. The motor neuron loss seen in the chronic low level injury was felt to be secondary to the loss of C7, C8, and T1 neurons adjacent to the injury epicenter.

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.

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.

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.

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.

Assessment of the malignant potential of mitogen stimulated human Schwann cells.

Human Schwann cells (SCs) can be isolated and expanded with mitogens using cell culture techniques. These cells have been demonstrated to promote axonal regrowth in both the central and peripheral nervous system. Primary rat SCs can be immortalized with long-term exposure to mitogens. Transplantation of these cells into an autogenic host sciatic nerve results in the formation of tumors. Human cells are, in general, relatively more resistant to malignant transformation, but any potential risk for inducing tumor after transplantation of SCs in humans must be excluded. In this study, the malignant potential of mitogen expanded human SCs injected into the sciatic nerve of immunodeficient mice was investigated. Human SCs were isolated from human peripheral nerves and placed in cell culture, expanded with mitogens (heregulin and forskolin) for many passages (0-6 times), and then injected within the sciatic nerve of Severe Combined Immunodeficient (SCID) rat or mice. As a positive control for tumor formation in this xenograft model, human glioma cells were also injected. The proliferation index (PI) of the human SCs gradually decreased with each passage in cell culture. SC purity remained stable until the 6th passage, and then decreased significantly for older passages, so that the cultures were over-grown with fibroblasts. The incidence for rat or human glioma cells to induce tumors was 100% and 92%, respectively. In contrast, there was no tumor induced by human primary or mitogen expanded SCs. Demyelination, remyelination and formation of connective sheath at the injection site were observed in some cases after injection of the human SCs. Thus, mitogen-expanded human SCs do not produce tumors when transplanted in vivo, which suggests that these cells are safe, and deserve further study towards their use in clinical transplantation.

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.

Cold preserved nerve allografts: changes in basement membrane, viability, immunogenicity, and regeneration.

Rat sciatic nerve graft segments were harvested and pretreated by either placement in the University of Wisconsin Cold Storage Solution at 5 degrees C and storage from 1 to 26 weeks, or repeatedly freezing (-40 degrees C) and thawing (20 degrees C). Following pretreatment, grafts were transplanted as either syngeneic or allogeneic nerve grafts. Storage and freeze-thawing did not affect the Schwann cell basal lamina or laminin distribution of the peripheral nerve. Graft cell viability decreased with increasing time of storage, with some viable cells detectable even after 3 weeks of storage. Freeze-thawed grafts were not viable. Increasing time of storage led to decreasing immune response and graft rejection, but improved regeneration. Freeze-thawed and 26-week stored allografts were nonimmunogenic and rejection was not seen, but regeneration was delayed compared to autografts. Graft storage may become a useful adjunct to clinical nerve allografting to permit elective scheduling of surgery, provide greater time for preoperative tissue testing, and possibly blunt the immune response.

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.

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.

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.