Total ankle arthroplasty: state of the art.

Total ankle arthroplasty results from the 1970s and 1980s were comparatively poor. The outcomes of these surgeries deteriorated rather dramatically with time. Causes of failure were multifactorial, but the 2 features that seemed central to implant failure were constrained designs and cement fixation. Total ankle operations are considered technically demanding procedures, with relatively high early postoperative complication rates. As yet, the ideal total ankle patient remains to be defined. With the current implant results as a guide, the optimal patient is an older person who is low demand and has multiple joint problems involving either the ipsilateral foot or knee or contralateral ankle. Good alignment and ligamentous stability are essential. Osteonecrosis and profound osteoporosis are associated with poor results due to problems with bony fixation. Patients should be advised that the implant may fail, and that this may require further surgery, including the potential need for an ankle fusion or below-knee amputation. The results of ankle fusions, although usually initially good, seem to deteriorate with time (Table 2). Not uncommonly, patients develop either transverse tarsal or subtalar degenerative joint disease several years after an ankle arthrodesis. Because of the associated pain and functional limitations that can follow ankle fusion, efforts to develop a workable total ankle replacement continue. At present, the long-term results of most new designs are unknown. Today, total ankle arthroplasty probably should be limited to centers where surgeons have the volume of patients to master the demanding techniques needed for these operations and conduct prospective clinical trials to determine what factors lead to successful and unsuccessful outcomes.