A Low-Cost Customizable Prosthetic Foot with Energy Return Capabilities

Background: Energy storage and return prosthetic feet improve the mobility of lower-limb amputees but prosthetic solutions available in the Under-Developed World do not meet the needs of active amputees. Case description and methods: This study aimed at developing and testing a hand-manufactured low-cost modular prosthetic foot with energy-return capabilities. Carbon fiber layers of varying stiffness were assembled to construct the toe section. Static tests were performed to measure the overall foot stiffness and ensure that our prototype withstands proof and ultimate loads. Two unilateral amputees performed gait trials to assess the prototype’s behaviour during gait. Findings and outcomes: Interchangeable toe layers enabled the prototype’s stiffness to vary between 31 and 40 N/mm, to withstand proof and ultimate ISO loads, and to return about 70% of the energy stored during loading. Two amputees tested the foot and were able to maintain temporal gait parameters within 10% of the values measured when using their own prosthetic feet. Conclusion: This study confirmed the feasibility of handmanufacturing a low-cost modular composite fibre prosthetic foot with energy return capabilities.