Lower limb prosthesis liner design for amputees with diabetes

This project investigates the needs of diabetic and vascular amputees to establish design criteria for a new lower-limb prosthesis liner specifically for diabetes and vascular patients. Initially, a literature review was conducted to investigate liner material properties and outcomes during use, as well as how often diabetic and older amputees were used as human subjects or referenced in prosthesis liner research. This literature review drew conclusions specifically for diabetes and vascular patients and proposed design considerations for this patient population. For additional design considerations, a formal contextual inquiry with patients, clinicians, Certified Prosthetists and Orthotists, podiatrists, and physiotherapists was conducted to learn more about diabetes and vascular patients, their prosthesis usage, their exercise routines, and patient care. Additionally, marketing and business perspectives are also included as design considerations, or inputs to the design criteria. It was found that the most important issues for the diabetic and vascular amputee are that liner and socket issues cause decreased prosthesis usage and decreased mobility and health. These liner and socket issues can be categorized into three root causes: the hard socket material, poor liner suspension, and sweat inside the liner. These root causes lead to pain, bruising, and wounds on the residual limb. Due to the decreased wound sensation and healing abilities found in diabetic and vascular patients, these patients cease or greatly decrease their prosthesis usage, leading to less mobility and decreased health. With this information, design criteria were developed. Afterformulating design criteria, conceptual solutions were brainstormed, developed and evaluated using the Harris Profile scoring system. Based on this scoring, the most appropriate conceptual solutions were prototyped. These design improvements were quantitatively evaluated against the relevant design criteria and a qualitatively evaluated based on user feedback. Improvements to amputee comfort and knee bending were achieved with the new design. Future work includes further prototyping and implementation of advanced concepts brainstormed in the conceptual solutions