User performance with a transradial multi-articulating hand prosthesis during pattern recognition and direct control home use

Individuals with a transradial amputation are often fitted with a hand or a hand and wrist prosthesis in attempts to restore functional ability. A wide variety of devices are available clinically, from single degree-of-freedom to multi-articulating hands, and include body-powered, myoelectric direct or pattern recognition control. The goal of this study was to investigate at-home use of a multi-articulating hand prosthesis. Individuals with a transradial amputation were fitted with and trained to use an OSSUR i-limb Ultra Revolution with Coapt COMPLETE CONTROL system. They participated in two 8-week home trials using the hand under myoelectric direct and pattern recognition control in a randomized order. While at home, participants demonstrated broader usage of grips in pattern recognition compared to direct control. After the home trial, they showed significant improvements in the Assessment of Capacity for Myoelectric Control outcome measure while using pattern recognition control compared to direct control; other outcome measures showed no differences between control styles. Additionally, this study provided a unique opportunity to evaluate EMG signal quality during home use. While EMG signal noise was identified during some pattern recognition calibrations, overall EMG quality was sufficient to provide users with control performance at or better than direct control.