Computerized tomography-based radiotherapy improves heterotopic ossification outcomes

To report the impact of computerized tomography (CT) based radiotherapy (RT) on heterotopic ossification (HO) outcomes.

This is a single institution, retrospective study of 532 patients who were treated for traumatic acetabular fractures (TAF). All patients underwent open-reduction internal-fixation (ORIF) of the TAF followed by RT for HO prophylaxis. Postoperative RT was delivered within 72h, in a single fraction of 7Gy. The patients were divided into 2 groups based on RT planning: CT (A) vs. clinical setup (B).

At a median follow up of 8years the incidence of HO was 21.6%. Multivariate regression analysis revealed that group (A) vs. (B) had HO incidence of 6.6% vs. 24.6% (p<0.001), respectively. Furthermore, HO Brooker grade ≥3 was observed in 2.2% vs. 10.8% (p=0.007) in group (A) vs. (B), respectively. Thus, the odds of developing HO and Brooker grades ≥3 were 4.7 and 4.5 times higher, respectively, in patients who underwent clinical setup.

Our data suggest that using CT based RT allowed more accurate delineation of the tissues and better clinical outcomes. Although CT-based RT is associated with additional cost the efficacy of CT-based RT reduces the risk of HO, thereby decreasing the need for additional surgical interventions.