Naproxen for 8 days can prevent heterotopic ossification after hip arthroplasty.

The effect of 1 week of treatment with naproxen on the formation of heterotopic ossification after cemented total hip arthroplasty was studied in a prospective trial. Twenty-seven patients received 500 mg naproxen twice daily for 7 days postoperatively. The medication was started on the morning of the operation. The results were compared with a control group of 23 patients from a previous study who had not received any type of non-steroidal antiinflammatory drug. All radiographs were mixed randomly, and patient identification was blinded. Three months after the operation, heterotopic ossification had developed in 12 (52%) patients in the control group and in 3 (11%) patients in the naproxen-treated group. One year after the operation, 4 (17%) patients in the naproxen-treated group and 12 (52%) in the control group had heterotopic ossification (p < 0.05). Severe ossification developed in 3 patients in the control group and in none in the naproxen-treated group. The authors conclude that naproxen given for 1 week can decrease the incidence of heterotopic ossification after total hip arthroplasty.