Radiation therapy for heterotopic ossification prophylaxis acutely after elbow trauma: a prospective randomized study.

BACKGROUND Heterotopic ossification around the elbow can result in pain, loss of motion, and impaired function. We hypothesized that a single dose of radiation therapy could be administered safely and acutely after elbow trauma, could decrease the number of elbows that would require surgical excision of heterotopic ossification, and might improve clinical results. METHODS A prospective randomized study was conducted at three medical centers. Patients with an intra-articular distal humeral fracture or a fracture-dislocation of the elbow with proximal radial and/or ulnar fractures were enrolled. Patients were randomized to receive either single-fraction radiation therapy of 700 cGy immediately postoperatively (within seventy-two hours) or nothing (the control group). Clinical and radiographic assessment was performed at six weeks, three months, and six months postoperatively. All adverse events and complications were documented prospectively. RESULTS This study was terminated prior to completion because of an unacceptably high number of adverse events reported in the treatment group. Data were available on forty-five of the forty-eight patients enrolled in this study. When the rate of complications was investigated, a significant difference was detected in the frequency of nonunion between the groups. Of the nine patients who had a nonunion, eight were in the treatment group. The nonunion rate was 38% (eight) of twenty-one patients in the treatment group, which was significantly different from the rate of 4% (one) of twenty-four patients in the control group (p = 0.007). There were no significant differences between the groups with regard to the prevalence of heterotopic ossification, postoperative range of motion, or Mayo Elbow Performance Score noted at the time of study termination. CONCLUSIONS This study demonstrated that postoperative single-fraction radiation therapy, when used acutely after elbow trauma for prophylaxis against heterotopic ossification, may play a role in increasing the rate of nonunion at the site of the fracture or an olecranon osteotomy. The clinical efficacy of radiation therapy could not be determined on the basis of the sample size. Further research is needed to determine the role of limited-field radiation for prophylaxis against heterotopic ossification after elbow trauma.