Nonoperative Treatment of Posterior Wall Acetabular Fractures After Dynamic Stress Examination Under Anesthesia: Revisited

Objectives: Performing an examination under general anesthesia (EUA) using dynamic stress fluoroscopy of patients with posterior wall acetabular fractures has been used as a tool to determine hip stability and the need for surgical intervention. The purpose of this study was to further evaluate the effectiveness of this technique, from a source other than its primary advocates, in patients with posterior wall acetabular fractures less than or equal to 50% who were stable on EUA and treated nonoperatively. Design: Retrospective case series. Setting: University Level 1 Trauma Center. Participants: Seventeen patients with a posterior wall acetabular fracture stable on EUA treated nonoperatively. Intervention: The patients were treated nonoperatively as guided by an EUA negative for instability. Patient follow-up averaged 30 months (range, 6-64 months). Main Outcome Measurements: Outcome evaluation included the modified Merle d'Aubigne clinical score and the Short Musculoskeletal Function Assessment Questionnaire. Radiographic evaluation for subluxation or arthritis consisted of the 3 standard pelvic radiographs. Results: Radiographic evaluation showed all hips to be congruent with a normal joint space. Sixteen of the 17 patients had radiographic outcomes rated as "excellent"; 1 patient was rated "good." The modified Merle d'Aubigne score (obtained in 12 patients) averaged very good, with only 1 having less than a good (graded as fair) clinical outcome. The Short Musculoskeletal Function Assessment Questionnaire scores (from 11 patients) were not significantly different from normal and were within the normal reported values for all indices and categories. There was no correlation between fracture fragment size and outcome. Conclusions: This study further supports the contention that a stable hip joint, as determined by EUA, after posterior wall acetabular fracture treated nonoperatively is predictive of continued joint congruity, an excellent radiographic outcome, and good-to-excellent early clinical and functional outcomes. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.