Load Bearing Capacity in Total Ankle Joint Replacement

Abstract

The influence of some simple design variations on the compressive load bearing capacity of tibial and talar prosthetic components in total ankle joint replacement were investigated in an attempt to suggest improvements to current prosthetic designs.

Eighteen paired ankle joint preparations were fitted with three types of tibial components and two types of talar components. The tibial component with an intramedullary peg tolerated significantly higher loads before mechanical failure than the two other designs that were equal in load bearing capacity. The mean value of ultimate force was 40 per cent higher and the mean value of yield force was 15 per cent higher. However, for the coefficient of stiffness there was a significant fall of 18 per cent in the mean value. The talar components were equal in load bearing capacity and stiffness.