Subtrochanteric femoral fractures due to simple bone cysts in children.

Seven children were treated surgically as a result of a pathologic fracture through a simple bone cyst in the subtrochanteric region of the proximal femur. Average age at surgery was 10.6 years. Six children were treated primarily. One child was operated for a refracture through a persistent cyst and malunion of a previous fracture that had been treated nonoperatively. Surgery included curettage of cysts in all patients. The cysts were filled with autologous bone graft in five patients and Osteoset bone substitute in two patients. The fracture was stabilized using a blade plate in three patients, a screw and side plate in three patients and an external fixator in one. At average follow-up of 4.7 years, all fractures had healed uneventfully. The cyst was fully obliterated in five patients and partially obliterated in two patients. One patient had a relative lengthening of 2 cm on the affected side. All patients were asymptomatic, fully active and had full range of motion.