Effect of indomethacin prophylaxis on heterotopic ossification after surgical fixation of elbow injuries: a randomized controlled trial.

BACKGROUND

Heterotopic ossification (HO) is a recognized complication following operative fixation of elbow trauma. While indomethacin prophylaxis is well established in hip and acetabular surgery, evidence for its role in elbow injuries remains limited. This randomized controlled trial evaluated whether oral indomethacin reduces the incidence and severity of HO after surgical treatment of acute elbow fractures and dislocations.

METHODS

Eighty-six adults with acute elbow injuries requiring surgical fixation were randomized 1:1 to receive either oral indomethacin (25 mg 3 times daily for three weeks) or no prophylaxis. Eighty-four patients completed follow-up. HO was assessed radiographically at scheduled intervals through the final follow-up and graded using the Hastings and Graham system. The Mantel-Haenszel method was used to calculate a pooled odds ratio adjusted for injury severity.

RESULTS

HO developed in 21 of 84 patients (25%), occurring in 14.3% of the indomethacin group vs. 35.7% of controls (P = .018), with indomethacin reducing both incidence (absolute risk reduction 21.4%; number needed to treat = 5) and severity (mean grade, 1.33 vs. 2.93, P = .013). All HO in the indomethacin group were low grade (G1-G2A), whereas high-grade HO (G2C-G3) occurred in 8 of 15 (53.3%) control patients. Stratified analysis demonstrated consistent trends across injury severity levels, with Mantel-Haenszel adjustment yielding similar estimates. Patients with HO in the indomethacin group had a greater range of motion compared to controls.

DISCUSSION AND

CONCLUSION

Indomethacin prophylaxis was associated with reduced incidence and severity of HO following operative fixation of elbow injuries. These findings should be interpreted in the context of baseline differences in injury severity between groups. Indomethacin may be a useful adjunct in patients at risk of HO following elbow trauma given its low cost, ease of administration and favorable safety profile, although further multicenter studies are required.