Achieving High Performance and Low Cost: Development of a High-Performing Passive Prosthetic Knee for Emerging Markets

Abstract

There is significant need for low-cost, high-performance prosthetic knees in low- and middle-income countries (LMICs) due to a large number of amputees and particularly challenging socioeconomic and environmental conditions. Prostheses are important for maintaining one’s participation in society, culture, and the economy, but many are either prohibitively expensive or do not provide near-able-bodied kinematics. Poor performing prosthetic knees cause discomfort and draw unwanted attention to transfemoral amputees. In this study, we refine the design of a high-performing, single-axis, passive prosthetic knee developed with a focus on the Indian market in order to reduce cost, weight, and part count; enhance manufacturability; and improve aesthetics. The load paths and functional componentry were critically analyzed to identify opportunities to streamline the design while maintaining strength and the near-able-bodied kinematics offered by the original design. The part count was reduced almost four-fold, and the mass of the prosthesis was reduced three-fold. An enclosure was also designed to encase the functional componentry in an aesthetically acceptable package. The changes made to the design are believed to significantly advance the usability and commercial viability of the prosthetic knee. This study may serve as an example of how products developed for emerging markets may achieve affordability without sacrificing performance.