Preventive cobalt therapy in heterotopic ossification consequent to prosthetic hip reimplantation.

Prosthetic hip reimplantation is considered to be a procedure at risk for the development of periprosthetic heterotopic ossification, which may be responsible for functional limitations of the hip operated on. Preventive treatment may be carried out with radiation or drug therapy. The authors report the results of 54 cases submitted to prosthetic reimplantation and treated by cobalt therapy, as compared to the results of 76 reimplantations (control group) that did not undergo any kind of treatment: the occurrence of high grade ossification (exceeding Brooker grade III) was 2% in cases treated, as compared to 9% in those not treated. Males were more at risk for the development of ossification.