[Radiation therapy in the prevention of periarticular, heterotopic ossification following implantation of a total hip endoprosthesis].

From June 1988 to January 1991 the efficacy of a low-dose (5 x 2 Gy) versus a high-dose (10 x 2 Gy, resp. 5 x 3,5 Gy) prophylactic postoperative radiotherapy was assessed in a prospective randomized trial. 60 patients at the highest risk for formation of heterotopic ossification (HO) were included in this study, i.e. patients that presented already HO in the ipsi- or contralateral hip at the time of surgery. After both irradiation regimen the incidence and severity of HO was significantly less than without prophylaxis; there was no significant difference (regarding the severity of HO, the hip score (16) and the hip mobility) between the two regimen.