Prevention of periarticular heterotopic ossification following total hip arthroplasty. Clinical experience with indomethacin and ibuprofen.

Prophylactic treatment with indomethacin or ibuprofen to prevent periarticular heterotopic ossification (PHO) was investigated in a consecutive series of 200 total hip replacements (THR) performed for primary coxarthrosis in 170 patients. No widespread PHO (grades III and IV) occurred in 166 THR treated with indomethacin or ibuprofen from the 1st to the 21st postoperative day. Only one patient exhibited moderate (grade-II) ossification. In contrast, the incidence of PHO grades III and IV was found to be high (23%) in the 35 THR for which the patients did not receive prophylaxis according to intention. It was concluded that 3 weeks' postoperative treatment with indomethacin or ibuprofen is sufficient to prevent the development of clinically significant heterotopic ossification.