Tibial rotation-plasty for proximal femoral focal deficiency.

The most common treatment for proximal femoral focal deficiency is amputation at the level of the ankle joint and subsequent prosthetic fitting in the manner used for an above-the-knee amputee. Since 1967, five patients with proximal femoral focal deficiency were treated with the Van Nes procedure -- an 180-degree tibial rotation-plasty to convert the ankle joint to a knee joint. Two of the five patients had excellent results -- the tibial rotation-plasty allowed the ankle joint to function as a knee joint with 90 degrees of flexion and placed it at the level of the contralateral anatomical knee. Fusion of the anatomical knee above the tibial rotation-plasty in these two patients provided a stable tibiofemoral lever arm that functioned as the thigh. Two patients had good results -- satisfactory functional and cosmetic improvement. In the remaining patient, who had associated paraxial fibular hemimelia with absence of the fourth and fifth rays of the foot, the result was a failure.