Rotationplasty about the knee: surgical technique and anatomical considerations.

Rotationplasty is an intercalary resection of a bone segment with subsequent reconstruction of the lower limb by rotating it through an arc of 180 degrees. After rotation, the rotated ankle functions as a knee joint, thereby powering a custom-made below-knee prosthesis. Rotationplasty is a satisfactory treatment option in selected patients. A prerequisite for this type of surgery is an intact sciatic nerve. Rotationplasty is indicated for skeletally immature patients with a tumoral lesion about the knee (<8-10 years of age), for older patients with large lesions that are not candidates for limb salvage as an alternative to above-knee amputation, and as a salvage procedure for chronically infected prosthetic implants. Preoperative planning includes the prediction of the exact remaining bone growth, because the ipsilateral distal tibial epiphysis will not completely substitute for the growth deficit resulting from the resected distal femoral and proximal tibial epiphyses. Therefore, minimal over length of the ankle of the operated leg is retained. Technical details of the surgery are described with particular emphasis on anatomical considerations. It provides a durable and biologic reconstruction and allows patients to become good functional below-knee prosthesis users and allows participation in recreational activities and sports.