Prostheses reduce the incidence of contralateral overuse syndrome in upper-limb amputees by encouraging balanced, bimanual limb usage. Benefits include reduced pain and muscular atrophy, increased productivity and self-reliance, improved self-image, a sense of well being, and increased social acceptance. Body- powered prostheses are used extensively in the United States (US) and abroad owing to their relative affordability, high reliability, and excellent utility. Invisible Hand Enterprises (IHE), LLC is developing an innovative biomimetic prehensile digit technology that will extend these benefits to two underserved populations: 1) partial-hand amputees, for whom very few components exist that enable useful grasp, and 2) upper-limb amputees worldwide who need prosthetic terminal devices resembling the anatomical hand with excellent cosmesis and realistic movement for reasons pertaining to social and cultural acceptance. In Phase I of this Small Business Innovation Research (SBIR) program, IHE demonstrated technological and economical viability of its core digit technology. Polymer resins and high-performance textile filaments replicate key structures and functions of the anatomical finger, resulting in devices that are low-cost, lightweight, exceptionally robust, and that require no lubrication. As modular building-blocks, the digits are clinically flexible, enabling prosthetists to create partial-hand prostheses optimized t function in concert with remaining natural digits. Incorporated into a whole-hand terminal device, the digits deliver cosmesis and movements that are psychologically satisfying to amputees, particularly females, and that help deflect attention in regions where stigmas against limb deficiencies are deeply entrenched and often lead to social rejection. In Phase II, IHE will make necessary design refinements and translate its core technology into a modular digit form suitable for commercial distribution. Digits will also be integrated into an existing hand structur, developed previously, that was highly praised by amputee evaluators but rejected for its lack of cable-operation and realistic movement. These products will be clinically evaluated using validated and industry-approved assessment protocols along with extended field performance validations, all performed by volunteer subjects. Manufacturing infrastructure and production processes will be established to support Phase III commercialization activities. Both modular digits and whole hand terminal devices will be brought to market as commercial products using IHE's existing US and international distributors, along with humanitarian agencies. IHE's mission is to delight amputees in the US and abroad by providing affordable new options that help them relish living and enjoy an even higher quality of life. This work is important and worthwhile, and wholly consistent with the spirit and purposes of the National Institute of Health's SBIR program.

Public Health Relevance

A new biomimetic prehensile digit technology is described that gives partial-hand prostheses and whole-hand terminal devices excellent cosmesis, realistic movement, and useful grasp. The technology addresses longstanding needs of partial-hand amputees who need affordable options, and upper-limb amputees abroad, particularly females, who require functional prosthetic hands to help them overcome cultural stigmas against disability. The devices proposed will help these amputees become productive members of society, bringing renewed self-sufficiency, sense of purpose, personal dignity, and improved quality of life.

National Institute of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Small Business Innovation Research Grants (SBIR) - Phase II (R44)
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Musculoskeletal Rehabilitation Sciences Study Section (MRS)
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Quatrano, Louis A
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Invisible Hand Enterprises, LLC
United States
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