The subcapsular approach for lesions of the femoral neck.

VOL. 75-B, No. 2, MARCH 1993 (Fig. 1). The usual below-knee amputation would have left too short a stump. We therefore decided to amputate the bone, 6 cm below the knee, and turn up a section of the healthy distal tibia on a long posterior flap to lengthen the stump. We excised the middle two-thirds of the tibia, with the anterior and lateral compartments, and disarticulated the foot at the ankle. A long posterior flap was fashioned to include all the posterior soft tissues down to and including the heel, with the distal 6 cm of tibia attached (Fig. 2a). This composite flap was turned up, and the two segments of tibia fixed together with wire (Figs 2b, c). The two disease-free portions of the tibia gave a belowknee stump of good length with the heel pad just below the patella (Fig. 3a). Bone union occurred and the stump functioned well, with flexion from 0#{176} to 100#{176} (Fig. 3b). Discussion. The bone-flap technique which we describe can be used to make below-knee amputation possible when a large part of the proximal tibial diaphysis is lost or is to be excised for extensive osteomyelitis, trauma or tumour. In our case only wide en-bloc resection was likely to succeed. When the knee is intact and distal tissues are healthy, either the distal tibia or the bones of the foot can be used to lengthen the proximal segment (Sanders 1989) and avoid the need for an above-knee amputation or knee disarticulation.