Prosthesis hand grasp control following targeted muscle reinnervation in individuals with transradial amputation

Transradial amputation is the most common level of major upper limb amputation. Despite the growing availability of multifunctional prosthetic hands, users control of these hands and overall functional abilities remain limited. The combination of pattern recognition control and targeted muscle reinnervation (TMR) surgery, an innovative technique where amputated nerves are transferred to reinnervate new muscle targets in the residual limb, has been used to improve prosthesis control of individuals with more proximal upper limb amputation levels (i.e., shoulder disarticulation and transhumeral amputation). The goal of this study was to determine if similar prosthesis control improvements could be seen for individuals with amputations at the transradial level. Participants controlled 3-5 grips with a multi-articulating hand prosthesis under myoelectric pattern recognition control for at least 8 weeks at home pre- and post-TMR surgery. Users gained some significant functional control benefits using a multi-articulating hand prosthesis with pattern recognition at 9-12 months post-TMR surgery. Additionally, a majority of subjects noted an improvement in their residual limb and phantom limb sensations post-TMR. An additional offline EMG analysis showed a decrease in grip classification error post-TMR surgery compared to pre-TMR surgery.