Total Ankle Arthroplasty for Posttraumatic Arthritis of the Ankle Joint
The ankle joint is a complex structure, comprising articulations between the distal tibia, the fibula, and the talus and constrained by multiple surrounding ligaments. Despite the high proteoglycan synthesis rate of ankle joint chondrocytes, posttraumatic arthritis is the most common etiology for end stage arthritis of the ankle. In select patients, especially patients who are too young for TAA, some surgeons recommend ankle distraction arthroplasty; however, the majority of end stage ankle arthritis is managed with either ankle arthrodesis (fusion) or total ankle arthroplasty (TAA). As techniques and outcomes improve, the indications for total ankle arthroplasty (TAA) are expanding, with many more surgeons favoring arthroplasty over arthrodesis. Several design factors such as mobile-bearing versus fixed-bearing prostheses, resurfacing versus flat cut talar components, intramedullary versus extramedullary referencing for component alignment, and, more recently, three-dimensional (3D) printing of patient-specific instrumentation (PSI). Advances in revision TAA, techniques for converting painful arthrodesis to TAA, and 3D printing, including custom implants and even total talus replacement, now enable preservation of motion over arthrodesis even in patients with complex ankle deformity and bone loss. Outcomes of TAA are generally favorable, but surgeons performing TAA must be prepared to manage potential complications such as wound breakdown, implant loosening, and infection. While revision TAA may be possible following even complex complications, the TAA surgeon must be familiar with salvage procedures, including tibio-talo-calcaneal arthrodesis with structural allograft or a 3D printed spacer, a procedure that is not as reliable in progressing to fusion as a primary ankle arthrodesis.
