Spring-Loaded Dynamic Foot: An Act of Product Development in Economically Developing Country

Abstract

208 ABSTRACT Introduction: There is a need for a new prosthetic foot in economically developing countries that is technically simple yet functionally more equivalent to the dynamic response foot. Objectives: The aim of this study is to develop and clinically evaluate a new prosthetic foot with a simple technical design that is as energy efficient as a dynamic response foot. Study Design: This study is a crossover repeated measures study design comparing the new prosthetic foot to the participant s conventional high-end or low-end prosthetic foot. Methods: Twenty-meter and 2-minute walk tests were performed to measure gait speed, and energy expenditure was estimated using the physiological cost index (PCI) for both the conventional prosthetic foot and the new spring-loaded dynamic (SLD) foot. Results: The gait speed with the SLD foot was on average 0.27 m/s faster than conventional low-end foot (P < 0.0001), but −0.18 m/s slower than conventional high-end prosthetic foot (P < 0.0001). The PCI was similar across all three prosthetic feet technologies (P = 0.276). Conclusions: Themobility function of the SLD foot was nearer to the dynamic response foot as comparedwith the low-end prosthetic foot. Given its technical simplicity and cost-effectiveness, the SLD foot may be considered as a true alternative to the existing dynamic response foot in economically developing countries. This article describes a new design of prosthetic foot that is simple in design, cost-effective, andmade from readily available local material, yet shows clinical features that are nearer to the dynamic response foot. With further immaculate clinical and mechanical testing, it can be integrated to prosthetic users in developing countries. (J Prosthet Orthot. 2021;33:208–212)