A 2-Week Course of Naproxen for Heterotopic Ossification Prophylaxis Is Effective Following Hip Arthroscopy for Femoroacetabular Impingement

PURPOSE: To evaluate the effectiveness of 2 weeks of naproxen prophylaxis for heterotopic ossification (HO) after primary hip arthroscopy for femoroacetabular impingement (FAI). METHODS: All consecutive hip arthroscopy cases by a single surgeon from January 1, 2015, to December 31, 2016, were retrospectively reviewed. Cases were included if they met the following criteria: (1) Primary hip arthroscopy, including femoral neck osteoplasty, for FAI; (2) naproxen prophylaxis for 2 weeks’ duration; and (3) radiographic follow-up at a minimum of 3 months postoperatively. Radiographic imaging for each patient was evaluated for the presence of HO, and independent radiology reports were used to confirm patients with HO. Maximal size of HO was measured and classified according to the Brooker criteria. Demographic and operative variables of the patients included in this study who received naproxen prophylaxis for 2 weeks were formally compared with a cohort of patients who received naproxen prophylaxis for 3 weeks in a previous randomized controlled trial. RESULTS: A total of 185 patients who received naproxen prophylaxis for 2 weeks were included in the study, 5 of whom developed HO (3%). A total of 48 patients who received naproxen prophylaxis for 3 weeks were included for comparison, 2 of whom developed HO (4%). There was no significant difference in the rate of HO formation between 2 weeks and 3 weeks of naproxen prophylaxis (P = .597). All 7 cases of HO were classified as Brooker class 1. CONCLUSIONS: The observed rate of postoperative heterotopic ossification after 2 weeks of naproxen prophylaxis in this study was equivalent to that observed after 3 weeks’ prophylaxis in a previously published study. Two weeks of naproxen prophylaxis may be a sufficient treatment course for the prevention of heterotopic ossification after primary hip arthroscopy for FAI. LEVEL OF EVIDENCE: Level III – Retrospective Comparative Study.