Presented: Yes
Presented at: AAOS Annual Meeting 2017

Authors: Darryl Auston, MD/PhD; Paul S. Whiting, MD; Frank R. Avilucea, MD; Michael Archdeacon, MD; Cory Collinge, MD; H. Claude Sagi, MD; Hassan R. Mir, MD, MBA, FACS
Author Affiliations: DA: OrthoOne, Thornton, CO; PSW, FRA, CC: Vanderbilt University, Nashville, TN; MA, HCS: University of Cincinnati, Cincinnati, OH; HRM: Florida Orthopaedic Institute, Tampa, FL

Introduction: Injuries to the pelvic ring are commonly seen following high-energy trauma. The ideal method for determining pelvic ring stability is a controversial topic in the orthopaedic trauma literature. Static radiographs or CT scans may not reflect the degree of displacement at the time of injury. The concept of dynamic pelvic instability has been increasingly recognized in the orthopaedic trauma literature and practice. Examination under anesthesia (EUA) has been advocated as a means of determining dynamic pelvic instability. Our purpose was to investigate the predictive value of a negative EUA for determining pelvic ring union without displacement.

Methods / Materials: Closed pelvic ring injuries at two academic level 1 trauma centers and one level 2 trauma center were identified that underwent pelvic EUA over a five year period. Operative reports and radiography were reviewed and all patients with a negative EUA were included in the analysis. A negative EUA was defined as one that did not reach operative criteria as defined in previous work by Sagi et al and was treated non-operatively (with no implants). Patient demographics, fracture classification, associated injuries, and post-operative weight-bearing status were recorded. Charts and radiographs were reviewed to determine union and displacement.

Results: 34 patients who had negative EUA of the pelvis were identified. Average age was 38.3 years (range 16-76), and 19 patients (55.8%) were males. 22 patients (64.7%) had Young-Burgess LC-1 injuries with complete sacral fractures, 4 patients (11.8%) had LC-2 injuries, and 8 patients (23.5%) had APC injuries. 7 patients (20.5%) had associated extremity injuries requiring restricted weight bearing for 6-12 weeks, while immediate weight-bearing as tolerated was permitted in the remaining 27 patients. Patients were followed for a minimum of 6 months or to union. No patients had displacement of their pelvic rings beyond the original deformity seen on injury films at the time of union. There were no instances of delayed operative fixation following negative EUA.

Discussion / Conclusion: Negative EUA accurately predicts pelvic ring union without displacement. No patient in our series required delayed pelvic ring fixation. Unless otherwise dictated by associated injuries, immediate weight-bearing as tolerated appears safe in the setting of a negative EUA.