Chemoprophylaxis for Heterotopic Ossification After Hip Arthroscopy: A Systematic Review and Meta-analysis.

Background: Heterotopic ossification (HO) is a common complication after hip arthroscopy that has historically been prophylactically treated with postoperative radiation. Newer prophylactic treatments use nonsteroidal anti-inflammatory drugs (NSAIDs) in place of radiation. Purpose: To examine the incidence of HO after hip arthroscopy with and without the use of chemoprophylactic agents. Study Design: Systematic review; Level of evidence, 4. Methods: PubMed and Scopus electronic databases were queried for all studies published between January 2000 and July 2025 that evaluated HO after hip arthroscopy. Information on study design, the use of exclusive NSAID chemical prophylaxis and regimen, presence of HO, and length of follow-up were collected from all studies. The Brooker classification was used for determining severity of HO. Matched-cohort studies were combined for meta-analysis and analyzed using the DerSimonian and Laird method of random-effects meta-analysis. Results: A total of 44 studies including a total of 32,603 patients were included. The incidence of HO in patients who received chemoprophylaxis after hip arthroscopy was 15.3 per 1000 patients per year compared with 80.1 per 1000 patients per year in those who did not receive chemoprophylaxis (P = .01). Patients who received chemoprophylaxis had a higher portion of Brooker 1 grade HO (73.6%) compared with patients who did not receive chemoprophylaxis (63.1%) (X 2 = 8.6558; P = .03). Meta-analysis of 6 studies comparing chemoprophylaxis with no chemoprophylaxis had an odds ratio of 0.10 (95% CI, 0.03-0.35; P < .001). Conclusion: Postoperative NSAIDs were effective in reducing the incidence and severity of HO after hip arthroscopy. Meta-analysis of matched-cohort studies estimated a 10-fold decrease in the incidence.