Functional Performance of Voluntary Opening and Closing Body Powered Prostheses

Inclusion criteria * Unilateral transradial or wrist-disarticulation amputee * 18 to 85 years of age * At least 1 year from date of amputation * Be able to independently provide informed consent * Be willing to comply with study procedures Exclusion criteria * History of acute or chronic skin breakdown on the residual limb * Prosthetic socket adjustment within 90 days * Any condition that would prevent participation and pose increased risk (e.g. shoulder impingement, sub-acromial bursitis, severe arthritis of the shoulder, elbow, wrist, or fingers) * Injuries of the upper limb within the past 90 days (surgeries, sprains, strains, or fractures). * Unwillingness/inability to follow instructions Inclusion criteria for able-bodied subjects * 18 to 85 years of age * Able to provide independent, informed consent * Independent function by self-report * Free of any health ailment that would impair physical function Exclusion criteria for able-bodied subjects * Younger than 18 or older than 85 years of age * Any condition that would prevent participation and pose increased risk (e.g. shoulder impingement, sub-acromial bursitis, severe arthritis of the shoulder, elbow, wrist, or fingers) * No injuries of the upper limb within the past 90 days (surgeries, sprains, strains, or fractures). * Unwillingness/inability to follow instructions