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Relationship of Sacral Fractures to Nerve Injury: Is the Denis Classification Still Accurate?
Jannat M Khan1, Alejandro Marquez-Lara, Anna N Miller
1*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.
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.
Design:
Retrospective case-control study.
Setting:
University Level I Trauma Center.
Patients/Participants:
One thousand five hundred seven consecutive patients who presented with sacral fractures between January 2000 and August 2012.
Main Outcome Measurements:
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.
Level Of Evidence:
Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
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