Proportional myoelectric control is still more refined. Electric arms are not without complications, especially for people who have nerve damage, excessive scar tissue or are missing an entire arm. When the wearer slightly shrugs, the shoulders pull on the harness and the sensor tells the arm to move. If at all possible, a myoelectric prosthesis should be worn for a trial period, giving the amputee and the rehabilitation team the opportunity to see if it is an appropriate prosthetic choice. A trial period also helps convince insurance companies which require proof of medical necessity before authorizing such a prosthesis.
Perseverance helps as well to show the wearer's motivation.
Even with the best instructions by the rehab team, wearing and using the prosthesis day to day, is of course, only under the amputee wearer's control. Harold H. Sears, Ph.D., is vice president of Iomed, inc., and general manager of Motion Control, which manufactures the Utah Arm. He received his doctorate in bioengineering in 1983 and was instrumental in developing the technology of myoelectric controls for upper extremity prostheses. Copyrighted by the Amputee Coalition of America. Local reproduction for use by ACA constituents is permitted as long as this copyright information is included.