ADAPTING THE BOSTON DIGITAL ARM TO ACCEPT FIVE INDEPENDENT INPUTS FROM TMR AMPUTEES

In conventional myoelectric control, muscles are assigned to control functions differing from those controlled in the intact limb. In 1984 a bilateral amputee was fitted with four myoelectric inputs around the shoulder. These were to be used in pairs to independently control operation of the gripper and elbow flexion-extension. Since none of the muscles were doing their original assignment, a program was set up to train the user on the system. After many sessions, the amputee and trainer agreed that simultaneous control was never going to work. The control system was reconfigured, and the user mastered controlling one device at a time sequentially with the two best control sites. Twenty years later people are again trying to control several devices simultaneously, but with a difference. Now, with targeted muscle reinnervation (TMR) each muscle is being used to control the same function as in the intact limb.