An artificial ankle joint.

Ankle fusion has been the time-honored treatment for painful debilitating conditions of the ankle due to osteoarthritis and rheumatoid arthritis. It is not a uniformly successful operation and has a high complication rate. If there is pre-existing disease in the knee or midtarsal joints, the pain is frequently made worse by ankle fusion. If there is no pre-existing disease, then painful degenerative changes frequently occur in the midtarsal joints subsequently. An artificial ankle joint has been used successfully since 1973 in patients who otherwise would require ankle fusion. The design of the prosthesis allows unrestricted motion in all planes. It also allows imperfect placement of the device without compromising results. The dome of the talus is not resected during insertion of the prosthesis. Only 1 cm of distal tibia is resected, thus allowing fusion without difficulty should it later become necessary. The superior position of the polyethylene device decreases wear from particulate matter which might settle by gravity. Study of 50 total ankle arthroplasty cases shows that predictably good results can be obtained in ankles with good stability, reasonably normal anatomy, and rheumatoids who are not on long-term steroid therapy.