title: Relationship of Sacral Fractures to Nerve Injury: Is the Denis Classification Still Accurate?
abstract: OBJECTIVE
  Use modern computed tomographic imaging to reassess neurological injury risks associated with zone I-III sacral fractures as originally described by Denis et al.
  
  
  METHODS
  Retrospective case-control study.
  
  
  METHODS
  University Level I Trauma Center.
  
  
  METHODS
  One thousand five hundred seven consecutive patients who presented with sacral fractures between January 2000 and August 2012.
  
  
  METHODS
  Patients were stratified based on the diagnosis of acute neurological injury. The risk of severe and complex sacral fractures based on the presence of nerve injury was assessed.
  
  
  RESULTS
  The rate of nerve injury was significantly lower compared with historic data (3.5% vs. 21.6%, P < 0.001). Acute nerve injury was a significant risk factor for displaced (odds ratio [OR]: 8.4, 95% confidence interval [CI], 1.4-51.9) and comminuted (OR: 5.2, 95% CI, 1.7-16.3) sacral fractures as well as zone II (OR: 3.4, 95% CI, 1.1-10.1) and III (OR: 3.9, 95% CI, 1.0-16.4) fractures.
  
  
  CONCLUSIONS
  The incidence of nerve injuries associated with sacral fractures is significantly lower than originally published by Denis et al. Patients with a nerve injury were highly correlated with having a displaced, comminuted, or zone III fracture, or spinopelvic dissociation; the authors recommend a fine cut computerized tomography for further investigation if these findings are not apparent on initial radiographic imaging.
  
  
  METHODS
  Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: *Department of Orthopaedic Surgery, Wake Forest University School of Medicine, Winston-Salem, NC; and †Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, MO.
authors.forename: Jannat M
authors.initials: JM
authors.lastname: Khan
authors.forename: Alejandro
authors.initials: A
authors.lastname: Marquez-Lara
authors.forename: Anna N
authors.initials: AN
authors.lastname: Miller
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015984:Causality; D015897:Comorbidity; D005260:Female; D006801:Humans; D015994:Incidence; D008160:Lumbosacral Plexus / Q000000981:diagnostic imaging / Q000293:injuries; D008297:Male; D008875:Middle Aged; D008923:Missouri / Q000453:epidemiology; D059348:Peripheral Nerve Injuries / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D012447:Sacrum / Q000000981:diagnostic imaging* / Q000293:injuries*; D012680:Sensitivity and Specificity; D016103:Spinal Fractures / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000706:statistics & numerical data; D015599:Trauma Severity Indices; D055815:Young Adult