Prevention of heterotopic ossification in hip arthroplasties by means of an early single-dose radiotherapy (6 Gy).

Radiotherapy has proven to be efficient in the prevention of heterotopic bone formation. Its importance is increasing in the treatment of uncemented implants in prosthetic hip surgery, where a localized irradiation field is applied to cover the bone-implant interface. In a prospective study the efficiency of two radiation concepts using two different doses to prevent heterotopic ossifications after total hip arthroplasties or revision arthroplasties was compared. In 7 patients after fractioned irradiation (5 × 2 Gy), two recurrences of periarticular ossification occurred, whilst in 17 patients after a single-shot irradiation of 6 Gy on the first postoperative day, no recurrences were seen. There were no side-effects from the radiation. Radiological signs of lucent cement-free implants or delayed wound-healing were absent. Thus, a single shot of 6 Gy applied within 24 h postoperatively reliably prevents heterotopic bone formation. It is safer than 5 × 2 Gy and facilitates the management of the patient.