Primary Versus Secondary Radiotherapy for Heterotopic Ossification Prevention About the Elbow.

OBJECTIVES: To examine the efficacy and safety of radiotherapy for the prevention of heterotopic ossification (HO) about the elbow.

DESIGN: Retrospective chart review.

SETTING: Level 1 Trauma Center.

PATIENTS/PARTICIPANTS: Two hundred and twenty-nine patients who received prophylactic radiotherapy (XRT) over a 15 year period were identified. Patients were included if they received XRT to the elbow joint and had at least 12 weeks of follow up after XRT. Fifty-four patients were ultimately included.

INTERVENTION: All patients were treated with a single dose of 7 Gy. 98% of patients received XRT within 24 hours after surgery, and all patients received XRT within 72 hours after surgery.

MAIN OUTCOMES MEASUREMENTS: The primary study measures evaluated were the presence or absence of clinically symptomatic HO and the presence of radiographic HO after XRT to the elbow joint.

RESULTS: Eighteen patients were treated with XRT after a traumatic injury requiring surgery (primary prophylaxis), and 36 were treated with XRT after excision surgery to remove HO which had already formed (secondary prophylaxis). In the primary cohort, 16.7% developed symptomatic HO after XRT, and 11.1% required surgery to resect heterotopic bone. In the secondary cohort, 11.1% developed symptomatic HO after surgery and XRT, and 5.5% required resection surgery. No secondary malignancies were identified.

CONCLUSIONS: Our findings suggest that XRT for elbow HO may be safe and effective for both primary and secondary HO. XRT for HO was not shown to be associated with radiation-induced sarcoma in this series, at least in the short term. Further study in a large patient population with extended follow up is required to better characterize populations at high risk for development of HO and secondary malignancy. [ZERO WIDTH SPACE].

LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.