title: Indomethacin prophylaxis for heterotopic ossification after acetabular fracture surgery increases the risk for nonunion of the posterior wall.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  Prospective randomized double-blinded trial.
  
  
  METHODS
  Level 1 regional trauma center.
  
  
  METHODS
  Skeletally mature patients treated operatively for an acute acetabular fracture through a Kocher-Langenbeck approach.
  
  
  METHODS
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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 mm for group 1, 33,800 mm for group 2, 6300 mm for group 3 (P = 0.005), and 11,100 mm 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).
  
  
  CONCLUSIONS
  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.
  
  
  METHODS
  Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: *Orthopaedic Trauma Service, Florida Orthopaedic Institute, Tampa, FL; and †Department of Orthopaedic Surgery, Harborview Medical Center, Seattle, WA.
authors.forename: H Claude
authors.initials: HC
authors.lastname: Sagi
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Jordan
authors.forename: David P
authors.initials: DP
authors.lastname: Barei
authors.forename: Rafael
authors.initials: R
authors.lastname: Serrano-Riera
authors.forename: Barbara
authors.initials: B
authors.lastname: Steverson
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging / Q000293:injuries / Q000601:surgery*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D017102:Fracture Healing / Q000187:drug effects; D050723:Fractures, Bone / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D005599:Fractures, Ununited / Q000139:chemically induced*; D006801:Humans; D007213:Indomethacin / Q000009:adverse effects* / Q000494:pharmacology / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009999:Ossification, Heterotopic / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control*; D011446:Prospective Studies; D011859:Radiography; D055815:Young Adult
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D007213:Indomethacin