Designing for Affordability, Application, and Performance: The International Transradial Adjustable Limb Prosthesis

摘要

A multidisciplinary team including engineers, prosthetists, physicians, and amputees has developed a new transradial prosthesis currently being validated. The International Transradial Adjustable Limb (ITAL) comprises an innovative variable-compression, variable-geometry below-elbow interface, a new body-powered prehensor with adjustable pinch force, control harness, and cable. Globally, prosthesis options are increasingly limited by cost and lack of infrastructure required to fit and maintain them. The ITAL was designed for use in harsh environments, with consideration of local technical knowledge and infrastructure available to economically disadvantaged amputees in the United States and developing countries. The relatively low-cost ITAL prostheses restore bimanual capacity to perform strenuous physical labor, enabling amputees to earn a living and be self-reliant. Packaged in kits, units can be taken directly to amputees and fit or serviced within about 1 hour using simple hand tools, without requiring amputees to visit or be transported to a central facility. Ten amputees in Jamaica, United States, Haiti, and Thailand have shown the ITAL to be an appropriate solution, and they now use it for daily activities. Users rate the ITAL's comfort at approximately 75% that of custom-fabricated prostheses but equivalent in utility. This article outlines key elements of the adjustable prehensor, the transradial interface, and the harness and presents a summary of results from the preliminary evaluation of the ITAL. Future work aims to further increase comfort while refining the aesthetics to address cultural needs.