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Objective: Nerve root decompression to relieve pain and radiculopathy remains one of the main goals of fusion-promoting procedures in the subaxial cervical spine. The use of allograft facet spacers has been suggested as a potential alternative for performing foraminotomies to increase the space available for the cervical nerve roots while providing segmental stiffening. Therefore, the goal of this cadaveric biomechanical study was to determine the acute changes in kinetics and foraminal area after the insertion of cortical bone facet spacers into the subaxial cervical spine., Methods: Allograft spacers (2 mm in height) were placed bilaterally into cadaveric cervical spine specimens (C2-T1, age of donors 57.5 ± 9.5 years, n = 7) at 1 (C4-5) and 3 (C3-6) levels with and without laminectomies and posterior lateral mass screw fixation. Standard stereophotogrammetry under pure moment loading was used to assess spinal kinetics. In addition, the authors performed 3D principal component analysis of CT scans to determine changes in foraminal cross-sectional area (FCSA) available for the spinal nerve roots., Results: Generally, the introduction of 2-mm-height facet spacers to the cervical spine produced mild, statistically insignificant reductions in motion with particular exceptions at the levels of implantation. No significant adjacent-level motion effects in any bending plane were observed. The addition of the posterior instrumentation (PI) to the intact spines resulted in statistically significant reductions in motion at all cervical levels and bending planes. The same kinetic results were obtained when PI was added to spines that also had facet spacers at 3 levels and spines that had been destabilized by en bloc laminectomy. The addition of 2-mm facet spacers at C3-4, C4-5, and C5-6 did produce statistically significant increases in FCSA at those levels., Conclusions: The addition of allograft cervical facet spacers should be considered a potential option to accomplish indirect foraminal decompression as measured in this cadaveric biomechanical study. However, 2-mm spacers without supplemental instrumentation do not provide significantly increased spinal segmental stability.

Object: One often overlooked aspect of spinal epidural abscesses (SEAs) is the timing of surgical management. Limited evidence is available correlating earlier intervention with outcomes. Spinal epidural abscesses, once a rare diagnosis carrying a poor prognosis, are steadily becoming more common, with one recent inpatient meta-analysis citing an approximate incidence of 1 in 10,000 admissions with a mortality approaching 16%. One key issue of contention is the benefit of rapid surgical management of SEA to maximize outcomes. Timing of surgical management is definitely one overlooked aspect of care in spinal infections. Therefore, the authors performed a retrospective analysis in which they evaluated patients who underwent early (evacuation within 24 hours) versus delayed surgical intervention (> 24 hours) from the point of diagnosis, in an attempt to test the hypothesis that earlier surgery results in improved outcomes., Methods: A retrospective review of a prospectively maintained adult neurosurgical database from 2009 to 2011 was conducted for patients with the diagnostic heading: epidural abscess, infection, osteomyelitis, osteodiscitis, spondylodiscitis, and abscess. The primary end point for each patient was neurological grade, measured as an American Spinal Injury Association Impairment Scale grade using hospital inpatient records on admission and discharge. Patients were divided into early surgical (< 24 hours) and delayed surgical cohorts., Results: Eighty-seven consecutive patients were identified (25 females; mean age 55.5 years, age range 18-87 years). Fifty-four patients received surgery within 24 hours of admission (mean time from admission to incision, 11.2 hours), and 33 underwent surgery longer than 24 hours (mean 59 hours) after admission. Of the 54 patients undergoing early surgery 45 (85%) had a neurological deficit, whereas in the delayed surgical group 21 (64%) of 33 patients presented with a neurological deficit (p = 0.09). Patients in the delayed surgery cohort were significantly older by 10 years (59.6 vs 51.8 years, p = 0.01). With regard to history of prior revision, body mass index, intravenous drug abuse, tobacco use, prior radiation therapy, diabetes, chronic systemic infection, and prior osteomyelitis, there were no significant differences. There was no significant difference between early and delayed surgery groups in neurological grade on presentation, discharge, or location of epidural abscess. The most common organism isolated was Staphylococcus aureus (n = 51, 59.3%). The incidence of methicillin-resistant S. aureus was 21% (18 of 87)., Conclusions: Evacuation within 24 hours appeared to have a relative advantage over delayed surgery with regard to discharge neurological grade. However, due to a limited, variable sample size, a significant benefit could not be shown. Further subgroup analyses with larger populations are required.

Object: Thoracolumbar spine injuries are commonly encountered in patients with trauma, accounting for almost 90% of all spinal fractures. Thoracolumbar burst fractures comprise a high percentage of these traumatic fractures (45%), and approximately half of the patients with this injury pattern are neurologically intact. However, a debate over complication rates associated with operative versus nonoperative management of various thoracolumbar fracture morphologies is ongoing, particularly concerning those patients presenting without a neurological deficit., Methods: A MEDLINE search for pertinent literature published between 1966 and December 2013 was conducted by 2 authors (G.G. and R.D.), who used 2 broad search terms to maximize the initial pool of manuscripts for screening. These terms were "operative lumbar spine adverse events" and "nonoperative lumbar spine adverse events.", Results: In an advanced MEDLINE search of the term "operative lumbar spine adverse events" on January 8, 2014, 1459 results were obtained. In a search of "nonoperative lumbar spine adverse events," 150 results were obtained. After a review of all abstracts for relevance to traumatic thoracolumbar spinal injuries, 62 abstracts were reviewed for the "operative" group and 21 abstracts were reviewed for the "nonoperative" group. A total of 14 manuscripts that met inclusion criteria for the operative group and 5 manuscripts that met criteria for the nonoperative group were included. There were a total of 919 and 436 patients in the operative and nonoperative treatment groups, respectively. There were no statistically significant differences between the groups with respect to age, sex, and length of stay. The mean ages were 43.17 years in the operative and 34.68 years in the nonoperative groups. The majority of patients in both groups were Frankel Grade E (342 and 319 in operative and nonoperative groups, respectively). Among the studies that reported the data, the mean length of stay was 14 days in the operative group and 20.75 in the nonoperative group. The incidence of all complications in the operative and nonoperative groups was 300 (32.6%) and 21 (4.8%), respectively (p = 0.1065). There was no significant difference between the 2 groups with respect to the incidence of pulmonary, thromboembolic, cardiac, and gastrointestinal complications. However, the incidence of infections (pneumonia, urinary tract infection, wound infection, and sepsis) was significantly higher in the operative group (p = 0.000875). The incidence of instrumentation failure and need for revision surgery was 4.35% (40 of 919), a significant morbidity, and an event unique to the operative category (p = 0.00396)., Conclusions: Due to the limited number of high-quality studies, conclusions related to complication rates of operative and nonoperative management of thoracolumbar traumatic injuries cannot be definitively made. Further prospective, randomized studies of operative versus nonoperative management of thoracolumbar and lumbar spine trauma, with standardized definitions of complications and matched patient cohorts, will aid in properly defining the risk-benefit ratio of surgery for thoracolumbar spine fractures.

Object: The authors performed a study to determine if lesion expansion occurs in humans during the early hours after spinal cord injury (SCI), as has been established in rodent models of SCI, and to identify factors that might predict lesion expansion., Methods: The authors studied 42 patients with acute cervical SCI and admission American Spinal Injury Association Impairment Scale Grades A (35 patients) and B (7 patients) in whom 2 consecutive MRI scans were obtained 3-134 hours after trauma. They recorded demographic data, clinical information, Injury Severity Score (ISS), admission MRI-documented spinal canal and cord characteristics, and management strategies., Results: The characteristics of the cohort were as follows: male/female ratio 37:5; mean age, 34.6 years; and cause of injury, motor vehicle collision, falls, and sport injuries in 40 of 42 cases. The first MRI study was performed 6.8 ±2.7 hours (mean ± SD) after injury, and the second was performed 54.5 ± 32.3 hours after injury. The rostrocaudal intramedullary length of the lesion on the first MRI scan was 59.2 ± 16.1 mm, whereas its length on the second was 88.5 ± 31.9 mm. The principal factors associated with lesion length on the first MRI study were the time between injury and imaging (p = 0.05) and the time to decompression (p = 0.03). The lesion's rate of rostrocaudal intramedullary expansion in the interval between the first and second MRI was 0.9 ± 0.8 mm/hour. The principal factors associated with the rate of expansion were the maximum spinal cord compression (p = 0.03) and the mechanism of injury (p = 0.05)., Conclusions: Spinal cord injury in humans is characterized by lesion expansion during the hours following trauma. Lesion expansion has a positive relationship with spinal cord compression and may be mitigated by early surgical decompression. Lesion expansion may be a novel surrogate measure by which to assess therapeutic effects in surgical or drug trials.