To determine if indomethacin has a positive clinical effect for the prophylaxis of heterotopic ossification (HO) after acetabular fracture surgery. To determine whether indomethacin affects the union rate of acetabular fractures.
Prospective randomized double-blinded trial.
Level 1 regional trauma center.
Skeletally mature patients treated operatively for an acute acetabular fracture through a Kocher–Langenbeck approach.
Patients were randomly allocated to 1 of 4 groups comparing placebo (group 1) to 3 days (group 2), 1 week (group 3), and 6 weeks (group 4) of indomethacin treatment.
Factors analyzed included the overall incidence, Brooker class and volume of HO, radiographic union of the acetabular fracture, and pain. Patients were followed clinically and radiographically at 6 weeks, 3 months, 6 months, and 1 year. Serum levels of indomethacin were drawn at 1 month to assess compliance. Computed tomographic scans were performed at 6 months to assess healing and volume of HO.
Ninety-eight patients were enrolled into this study, 68 completed the follow-up and had the 6-month computed tomographic scan, and there was a 63% compliance rate with the treatment regimen. Overall incidence of HO was 67% for group 1, 29% for group 2 (P = 0.04), 29% for group 3 (P = 0.019), and 67% for group 4. The volume of HO formation was 17,900 mm3 for group 1, 33,800 mm3 for group 2, 6300 mm3 for group 3 (P = 0.005), and 11,100 mm3 for group 4. The incidence of radiographic nonunion was 19% for group 1, 35% for group 2, 24% for group 3, and 62% for group 4 (P = 0.012). Seventy-seven percent of the nonunions involved the posterior wall segment. Pain visual analog scores (VASs) were significantly higher for patients with radiographic nonunion (VAS 4 vs. VAS 1, P = 0.002).
Treatment with 6 weeks of indomethacin does not appear to have a therapeutic effect for decreasing HO formation after acetabular fracture surgery and appears to increase the incidence of nonunion. Treatment with 1 week of indomethacin may be beneficial for decreasing the volume of HO formation without increasing the incidence of nonunion.
Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
*Orthopaedic Trauma Service, Florida Orthopaedic Institute, Tampa, FL; and
†Department of Orthopaedic Surgery, Harborview Medical Center, Seattle, WA.
Reprints: H. Claude Sagi, MD, FACS, Orthopaedic Trauma Service, Florida Orthopaedic Institute, Tampa General Hospital, 5 Tampa General Circle, Suite 710, Tampa, FL 33606 (e-mail: email@example.com).
The authors report no conflict of interest.
Supported through a grant provided by the Orthopedic Research and Education Foundation.
Presented in part at the Annual Meeting of the Orthopaedic Trauma Association, October 2012, Minneapolis, MN.
Accepted September 12, 2013