The Crescent Fracture: A Posterior Fracture Dislocation of the Sacroiliac Joint

Summary Between October 1987 and August 1992, 22 patients with crescent fractures, a posterior fracture-dislocation of the sacroiliac joint, were admitted, treated, and available for review at Tampa General Hospital and The Hospital for Special Surgery. The purpose of the study was twofold: (a) to evaluate the incidence, severity, and pattern of associated injuries, and (b) to determine the efficacy of a treatment protocol using a posterior extrapelvic approach and extraarticular internal fixation. The study population was composed of 13 females and nine males; the average age was 25 years (range 10-52). Despite the fracture pattern resulting in a rotationally unstable hemipelvis, all patients were hemodynamically stable at the time of presentation. Fourteen patients (64%) had other associated injuries, including five (23%) with closed head injury. In all cases a posterior extrapelvic approach was used with an anatomic reduction of the fractured iliac wing and the sacroiliac joint dislocation. Stable extraarticular internal fixation was obtained using inter-table lag screws and outer-table neutralization plates. All the fractures were clinically and radiographically healed within 8-10 weeks postoperatively, and there were no acute wound, neurologic, or vascular complications. One patient developed osteomyelitis of the iliac crest 6 months postoperatively.