Myoelectric Prosthesis for a Partial Hand Amputee

ROBERT PICKEN, CP* Chicago, Illinois

A 6-year-old girl with transmetacarpal amputation was fitted with a myoelectric prosthesis using the intrinsic muscles of the hand for control of the prosthesis. She could operate the myoelectric hand when it was unattached for fitting purposes. When the hand was attached to the partial hand socket, the child was unable to lift or operate it. As a result, she was fitted as a wrist disarticulation amputee with a socket crossing, and therefore immobilizing, the wrist joint. To save length, the wrist unit of the VV2-6 hand was replaced with a low-profile connecting piece that fitted into the hand shell. Batteries and the myoprocessor were installed in the hand and covered with a custom-made shell. Flexible electrodes and cables were laminated into the socket. Metal clips were exposed for recharging and a magnet was used to open and close the on/off switch in the myoprocessor. The result was a partial hand myoelectric prosthesis that was not significantly longer than the contralateral side.

*Rehabilitation Institute of Chicago, 345 East Superior Street, Chicago, IL 60611