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Publications (4)9.78 Total impact

  • Article: The Impact of Facet Dislocation on Clinical Outcomes after Cervical Spinal Cord Injury: Results of a Multicenter North American Prospective Cohort Study.
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    ABSTRACT: Study Design. Multicenter prospective cohort study.Objective. To define differences in baseline characteristics and long-term clinical outcomes between cervical SCI patients with and without Facet Dislocation (FD).Summary of Background Data. Reports of dramatic neurological improvement in patients with FD and cervical SCI, treated with rapid reduction, have led to the hypothesis that this represents a subgroup of patients with significant recovery potential. However, without a large systematic comparative analysis, this hypothesis remains untested.Methods. Patients were classified into FD and non-FD groups based on imaging investigations at admission. The primary outcome was change in ASIA motor score (AMS) at 1-year follow-up. Secondary outcome measures included ASIA Impairment Scale (AIS) grade conversion and Functional Independence Measure score at 1-year post injury, as well as length of acute hospitalization. Baseline characteristics and long-term outcomes were also compared between patients with unilateral and bilateral FD.Results. Of 421 patients enrolled, 135(32.1%) had FD and 286(67.9%) had no FD. Patients in the FD group had a significantly worse presenting AIS grade and higher energy injury mechanisms (p<0.01). Bilateral FD patients had a greater severity of baseline neurological deficit compared to those with unilateral FD, as measured by AIS grade and AMS. The mean length of acute hospitalization was 41.2 days amongst FD patients and 30.0 amongst non-FD patients (p = 0.04). At 1-year follow-up, FD patients experienced a mean AMS improvement of 18.0 points, whereas non-FD patients experienced an improvement of 27.9 points (p<0.01). In performing an adjusted analysis, with backwards elimination of predictors with a p-value>0.05, FD patients continued to demonstrate less AMS recovery as compared to the non-FD patients (p = 0.04).Conclusion. As compared to those without FD, cervical SCI patients with FD tended to present with a more severe degree of initial injury and displayed less potential for motor recovery at 1-year follow-up.
    Spine 08/2012; · 2.08 Impact Factor
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    Article: Early versus delayed decompression for traumatic cervical spinal cord injury: results of the Surgical Timing in Acute Spinal Cord Injury Study (STASCIS).
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    ABSTRACT: There is convincing preclinical evidence that early decompression in the setting of spinal cord injury (SCI) improves neurologic outcomes. However, the effect of early surgical decompression in patients with acute SCI remains uncertain. Our objective was to evaluate the relative effectiveness of early (<24 hours after injury) versus late (≥ 24 hours after injury) decompressive surgery after traumatic cervical SCI. We performed a multicenter, international, prospective cohort study (Surgical Timing In Acute Spinal Cord Injury Study: STASCIS) in adults aged 16-80 with cervical SCI. Enrolment occurred between 2002 and 2009 at 6 North American centers. The primary outcome was ordinal change in ASIA Impairment Scale (AIS) grade at 6 months follow-up. Secondary outcomes included assessments of complications rates and mortality. A total of 313 patients with acute cervical SCI were enrolled. Of these, 182 underwent early surgery, at a mean of 14.2(± 5.4) hours, with the remaining 131 having late surgery, at a mean of 48.3(± 29.3) hours. Of the 222 patients with follow-up available at 6 months post injury, 19.8% of patients undergoing early surgery showed a ≥ 2 grade improvement in AIS compared to 8.8% in the late decompression group (OR = 2.57, 95% CI:1.11,5.97). In the multivariate analysis, adjusted for preoperative neurological status and steroid administration, the odds of at least a 2 grade AIS improvement were 2.8 times higher amongst those who underwent early surgery as compared to those who underwent late surgery (OR = 2.83, 95% CI:1.10,7.28). During the 30 day post injury period, there was 1 mortality in both of the surgical groups. Complications occurred in 24.2% of early surgery patients and 30.5% of late surgery patients (p = 0.21). Decompression prior to 24 hours after SCI can be performed safely and is associated with improved neurologic outcome, defined as at least a 2 grade AIS improvement at 6 months follow-up.
    PLoS ONE 01/2012; 7(2):e32037. · 4.09 Impact Factor
  • Article: Reliability and reproducibility of subaxial cervical injury description system: a standardized nomenclature schema.
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    ABSTRACT: Radiographic measurement study. To develop a standardized cervical injury nomenclature system to facilitate description, communication, and classification among health care providers. The reliability and reproducibility of this system was then examined. Description of subaxial cervical injuries is critical for treatment decision making and comparing scientific reports of outcomes. Despite a number of available classification systems, surgeons, and researchers continue to use descriptive nomenclature, such as "burst" and "teardrop" fractures, to describe injuries. However, there is considerable inconsistency with use of such terms in the literature. Eleven distinct injury types and associated definitions were established for the subaxial cervical spine and subsequently refined by members of the Spine Trauma Study Group. A series of 18 cases of patients with a broad spectrum of subaxial cervical spine injuries was prepared and distributed to surgeon raters. Each rater was provided with the full nomenclature document and asked to select primary and secondary injury types for each case. After receipt of the raters' first round of classifications, the cases were resorted and returned to the raters for a second round of review. Interrater and intrarater reliabilities were calculated as percent agreement and Cohen kappa (κ) values. Intrarater reliability was assessed by comparing a given rater's diagnosis from the first and second rounds. Nineteen surgeons completed the first and second rounds of the study. Overall, the system demonstrated 56.4% interrater agreement and 72.8% intrarater agreement. Overall, interrater κ values demonstrated moderate agreement while intrarater κ values showed substantial agreement. Analyzed by injury types, only four (burst fractures, lateral mass fractures, flexion teardrop fractures, and anterior distraction injuries) demonstrated greater than 50% interrater agreement. This study demonstrated that, even in ideal circumstances, there is only moderate agreement among raters regarding cervical injury nomenclature. It is hoped that more familiarity with the proposed system will increase reproducibility in the future. Additional research is required to establish the clinical utility of this novel nomenclature schema.
    Spine 05/2011; 36(17):E1140-4. · 2.08 Impact Factor
  • Article: Mean subaxial space available for the cord index as a novel method of measuring cervical spine geometry to predict the chronic stinger syndrome in American football players.
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    ABSTRACT: The chronic stinger syndrome is a distinct entity from acute stingers and has been shown to have its own pathophysiology that, unlike acute stingers, may reflect long-standing geometrical changes of the subaxial spinal canal and chronic irritation/degeneration of the exiting nerve root complex. There is no method available, however, to accurately predict these symptoms in athletes. The mean subaxial cervical space available for the cord (MSCSAC) is a novel alternative to the Torg ratio for predicting neurological symptoms caused by cervical spondylosis in elite athletes. It is the goal of this study to determine critical values for this measurement index and to retrospectively correlate those values to neurological symptoms. Magnetic resonance images obtained in 103 male athletes participating in the 2005 and 2006 National Football League Scouting Combine and a control group of 42 age-matched male nonathletes were retrospectively reviewed. The Torg ratio and SAC values were calculated in triplicate at each cervical level from C3-6 by using lateral radiographs and midsagittal T2-weighted MR images of the cervical spine, respectively. These values were then averaged for each individual to produce mean subaxial cervical Torg ratio (MSCTR) and MSCSAC values. Receiver operating characteristic curves were constructed for each measurement technique and were compared based on their respective area under the curves (AUCs). The MSCSAC difference between athletes with and without chronic stingers was statistically significant (p < 0.01). The difference between athletes with and without chronic stingers compared with controls was also statistically significant (p < 0.001 and p < 0.001, respectively). The AUC for the MSCSAC was 0.813, which was significantly greater than the AUC for both the MSCTR (p = 0.0475) and the individual Torg ratio (p = 0.0277). The MSCTR had the second largest AUC (0.676) and the conventional method of measuring individual Torg ratio values produced the lowest AUC (0.661). It was found that using the MSCSAC with a critical value of 5.0 mm produced a sensitivity of 80% and a negative likelihood ratio of 0.23 for predicting chronic stingers. Lowering the cutoff value to 4.3 mm for the MSCSAC resulted in a possible confirmatory test with a specificity of 96% and a positive likelihood ratio of 13.25. A critical value of 5.0 mm for the MSCSAC provides the clinician with a screening test for chronic stingers and anything < 4.3 mm adds additional confidence as a confirmatory test. These results are approximately 20% more accurate than the classic Torg ratio based on our AUC analysis. It was found that measuring the spinal geometry throughout the length of the subaxial cervical spine produced a more reliable method by which to predict neurological symptoms than the traditional approach of measuring individual levels. This shows that the underlying pathogenesis of the chronic stinger syndrome is best characterized as a process that involves the entire subaxial region uniformly.
    Journal of Neurosurgery Spine 09/2009; 11(3):264-71. · 1.53 Impact Factor