Remarkable advances in signal processing techniques, materials sciences, battery technologies, and computer-aided design and computer-aided manufacturing (CAD/CAM) processes have led to significant developments in assistive technologies. Coordinated research and commercialization have dramatically increased prosthetic function, utility, personalization, comfort-and unfortunately, cost. The initial cost of modern upper-extremity prostheses ranges from US$10,000 to US$40,000 (excluding recurring costs for maintenance and repair), placing them well-beyond the economic reach of many amputees worldwide. The extensive customization required to create modern sockets is a large component of the initial and recurring cost;socket replacement and refitting is recommended every three to five years. The monetary cost of purchasing, repairing, and maintaining prostheses combined with a lack of clinical infrastructure in some countries precludes a large percentage of the world's amputee population from accessing modern prosthetic technologies. In response to diverse patient needs, increasingly restrictive insurance regulations, and laws prohibiting the re-use of equipment, clinical prosthetists are faced with an urgent need for new prosthetic technologies that are 1) economically appropriate for disadvantaged persons, 2) designed to withstand repetitive rigorous use, and 3) easily fit on amputees without extensive customization. The critical element necessary to satisfy this need is an economically and technologically viable upper extremity socket (UES). Phase I of this proposed Small Business Innovation Research (SBIR) project successfully demonstrated the technical and economic feasibility of creating a low-cost UES that can be easily adjusted to accommodate residual limb variations in shape and volume over a defined size range (representative of a selected quartile of amputees). Elastic, rigid, and compliant materials were used to realize a design that remains stable and comfortable when used to support a load of 50 lbs during the performance of physically demanding activities such as lifting, pulling, and other actions commonly associated with farming, ranching, and manual labor. The design is easily adjustable, able to be fit on individuals within one (1) hour, and in production quantities has a manufacturing cost of less than US$50. Phase II encompasses making design refinements identified in Phase I and using anthropometric dimensional data from the protective equipment and garment industries to expand the basic socket design into a family of products covering three standard sizes: small (S), medium (M), and large (L). Manufacturing infrastructure will be established to produce commercial product for release into the marketplace in Phase III. This research effort has been intentionally formulated to address an important need revealed by the market, and to use NIH funding in a way that will significantly benefit disadvantaged men, women, and children in the United States and abroad who are affected by upper-limb deficiencies, in keeping with the spirit and purposes of the SBIR program.
Modern prosthetic sockets are highly functional, require extensive customization, and are prohibitively expensive for some individuals. A versatile new prosthetic socket for upper-limb amputees has been devised using advanced engineering methods and materials to realize appreciable cost savings. The socket is easily adjustable for individual users, is comfortable and stable, and enables disadvantaged amputees to perform physically demanding tasks associated with agricultural work and subsistence farming.