Indomethacin versus meloxicam for prevention of heterotopic ossification after total hip arthroplasty

Heterotopic ossification (HO) is a recognized postsurgical complication after total hip arthroplasty. Brooker et al. [6] established a grading system to define the degree of HO. The results of several studies have shown that non-steroidal anti-inflammatory drugs (NSAID) and radiation therapy reliably reduce the occurrence of severe HO. The exact cause and mechanism of bone formation are not known. The efficacy of indomethacin versus meloxicam for the prevention of heterotopic periarticular ossification and clinical NSAID side-effects after primary, cementless total hip arthroplasty was evaluated.

Probands underwent cementless total hip replacements at the Orthopaedic Department, Hospital Wiener Neustadt, from January 1997 to January 1998, did not take NSAID up to 4 weeks preoperatively and had no NSAID contraindications. Patients were separated into two groups by different hospitalisation floors. All patients selected for this study suffered from primary or secondary coxarthrosis. Data were collected as a prospective, randomised, parallel group study. Patients were given 50 mg indomethacin 2 times daily ( n=58) vs 7.5 mg meloxicam ( n=58) in a 12-day treatment course.

A two-sided Cochran-Armitage trend test showed no statistically significant difference ( p<0.05) for one of the drugs regarding influence on ectopic bone formation according to the grading system of Brooker et al.

Our study demonstrates that there is no statistically significant trend that indomethacin or meloxicam protects a hip arthroplasty better from heterotopic bone formation. We prefer indomethacin therapy because it is almost half the price of meloxicam therapy, and we recommend indomethacin in a 12-day treatment course given 50 mg 2 times daily as an effective, inexpensive and easily administered HO prophylaxis.