A review of the STAR prosthetic system and the biomechanical considerations in total ankle replacements.

The ankle is a complex joint, anatomically and biomechanically. Pathologically diseased ankle joints, which require surgical intervention, now have the option of a total ankle replacement system rather than the long-standing arthrodesis procedure, first described by Albert in 1878. The anatomical features and forces acting across the joint are important when designing total ankle replacement (TAR) systems. This review discusses the history and evolution of TAR prosthetic systems and considers how the ankle's normal physiology and biomechanics is incorporated into their design. The Scandinavian total ankle replacement (STAR) is a three component prosthetic system and this review concludes that its size, shape and surgical insertion technique allows the biomechanical requirements of the ankle to be met with an adequate stress distribution in particular.