Pathological fractures secondary to unicameral bone cysts.

We carried out a retrospective review of 75 children with unicameral bone cysts, who had sustained 52 pathological fractures, to determine which cysts were likely to be at risk and whether healing was accelerated after a fracture. Most lesions were in the metaphysis of a tubular bone, the commonest sites being the the upper part of the humerus and femur. The percentage of bone occupied by the cyst in the transverse plane was more than 85% in both anteroposterior and lateral radiographs in every case of pathological fracture. In most cases, the cyst recurred and sometimes became large without any acceleration of healing.