Efficiency of dynamic elastic response prosthetic feet.

Following years of accepting the Solid Ankle Cushion Heel (SACH) foot as the optimum compromise between durability and functional effectiveness, as well as being of reasonable cost, several new feet with dynamic elastic response qualities have been designed. The stimulus for these new designs is the recent development of materials which offer the potential to "store and release energy" in a manner that facilitates walking and running . Numerous new prosthetic feet have become available commercially. The effectiveness of these designs is not known, though each has its strong clinical advocates (1,2,3,4). It is claimed that these feet reduce the energy required for walking, and increase mobility. Four dynamic elastic response (DER) feet representative of this design were selected for study. The objectives of this project were to compare the efficiency of four DER prosthetic foot designs (Seattle, Flex-Foot, Carbon Copy II, Sten) to that of the traditional SACH foot ; define the gait mechanics induced by each foot ; and determine the relative effectiveness and cost/benefit ratio of these new feet for the dysvascular and traumatic amputee populations.