TMR Improves Performance of Compensatory Tracking Using Myoelectric Control

We explored the performance of a glenohumeral TMR (targeted muscle reinnervation) patient in controlling the activity of two reinnervated muscles of the chest and back during a compensatory tracking task that implied quick switches of activity between the two muscles. The same task was conducted in intact-bodied subjects, using either the wrist flexor/extensor muscles (innervated by the nerves were used as donors in the TMR patient) or the chest/back muscles that were re-innervated in the patient following the TMR. As expected, the intact-bodied subjects showed better control performance when using the wrist muscles than when using the chest and back muscles. Using the reinnervated chest and back muscles, the TMR patient performed similarly in the compensatory task than the able-bodied subjects when they used wrist muscles and his performance was superior than that of the able-bodied subjects using their chest and back muscles for control. These results indicate that the control properties have been improved through TMR.