Heterotopic ossification and other perioperative complications of acetabular fractures.

Thirty-eight operatively treated fractures of the acetabulum were evaluated retrospectively for perioperative complications. Functionally significant heterotopic ossification (Brooker class III or IV) developed in 23% of those patients who did not receive adequate prophylactic irradiation or indomethacin. Irradiation and indomethacin were effective in the prevention of severe heterotopic ossification. The development of severe heterotopic ossification (class III or IV) was associated with increased time from injury to operation. We conclude that prophylaxis against heterotopic ossification is warranted to decrease the incidence of this potentially preventable complication in patients who incur significant time delays prior to surgery. Other significant complications included avascular necrosis (26%), infection (13%), and neural injury (16%). Avascular necrosis developed in one patient who did not have a documented dislocation.