Heterotopic bone formation affecting the hip joint is preventable in high risk patients by post-operative radiation

Between 1984 and 1993, 40 high risk patients (45 hips) received postoperative irradiation as prophylaxis against heterotopic ossification (HO). Radiotherapy was commenced within 5 days of the surgery in 43 of 45 hips. The development of HO was assessed by comparison of radiographic films prior to irradiation and at least 2 months after treatment (median interval 12 months). Progression of HO was observed in only two of 45 hips (4.3%) and of clinical significance in one (2.2%). Treatment was well tolerated with no acute complications or loosening of prosthetic components attributable to irradiation. During the study period, the treatment programme changed from 20 Gy in 10 fractions to 6-8 Gy in a single fraction, without loss of treatment efficacy. As well as improving resource utilization, single fraction techniques allow fewer patient transfers thereby reducing patient discomfort and risk of hip dislocation. This procedure is uncomplicated and should be considered more widely in the management of this disabling non-malignant condition.