- Targeted Muscle Reinnervation (TMR): TMR is a technique whereby a series of nerve transfers is utilized to reinnervate specific target muscles to create additional prosthetic control sites after proximal limb amputation. These nerve transfers offer intuitive control of distal prostheses because the reinnervated muscles are controlled by the same nerves that once innervated the amputated limb. Signals created by the residual nerves are amplified by the recipient muscles, which are captured by surface electrodes and transduced to the distal prosthesis. TMR procedures have been performed on more than 40 patients to date. Limitations of this technique, however, include the finite number of available electromyographic signal sites due to anatomic constraints and issues with long-term signal fidelity.