In modern prosthetics a suction liner provides a mechanical connection to the rigid socket by ?gripping? the residual limb of the patient by either skin traction or suction. Conventionally, liners are made from materials that are impermeable to water such as silicone and polyurethane. Prolonged moisture accumulation inside the liner adversely affects fit and contributes to issues such as maceration (tissue softening from constant water exposure), breakdown, and infection, as well as issues of comfort and hygiene. Managing this issue could revolutionize the clinical implementation of this widely used suspension system. We propose to develop a new type of advanced-material prosthetic liner system that maintains skin traction and suction but also absorbs, wicks, channels, and manages the water from sweat. This material will improve clinical practice by providing a more stable, comfortable, and less problematic interface between the limb and socket. Our objective is to develop a highly cross-linked prototype hydrated material system, for use in place of the water-impermeable silicone liner, to maintain airless skin traction and suction while managing sweat and keeping a static volume in relation to water content. This new liner material will require the development of two advanced materials, a sweat- transporting medium incorporating silicone cellulose nanocrystal nanocomposites (CNCs), and a polymer/clay aerogel which can absorb and retain moisture until it is deliberately removed. Both of these materials will be developed and tested to optimize their mechanical and sweat-diffusion properties. Finally, these materials will be layered along with a third, sealant layer made of standard liner silicone into a three-layered prototype for further mechanical, sweat management, durability, and regeneration testing aswellashygieneexaminationcoupledtofunctionalevaluationofthematerialinarigid walkingboot. Improving water management in this critical component will fundamentally improve standard of care for a large population of lower and upper limb amputees.
This proposal aims to develop a new prosthetic socket liner material to transport and sequester sweat away from an amputee's skin. The number of amputees, particularly double- and triple-amputees, in our veteran population has steadily increased over the last decade. Meanwhile, advances in prosthesis technology have produced devices with increasing functional potential of which our veteran amputee users want to take full advantage. In contrast, conventional silicone socket liners have advanced relatively little, including an undesirable tendency to accumulate sweat during use, particularly for physically active amputees. A liner material which keeps this moisture away from the user's skin would not only improve comfort and hygiene, but also the critically-important fit and thus the overall performance of the prosthesis.