Developing a Myoelectric-Driven Rehabilitation Robot for Acquiring Upper-Limb Muscle-Coordinated Activity Patterns in Patients with Post-Stroke Hemiplegia

We explored the efficacy of a myoelectric-driven rehabilitation robot in enhancing upper limb motor function among patients with post-stroke hemiplegia, focusing on the potential of targeted muscle activity during reaching. Four individuals with chronic stroke underwent a training regimen involving reaching movements in eight directions, utilizing a robot that activates specific muscle activity patterns pertinent to the reaching direction. The training spanned 1–2 months, comprising 8 sessions, with each session consisting of 3 sets of 10 reaching motions in each direction. The training effectiveness was evaluated using four indices: normalized integrated electromyogram (IEMG), number of velocity peaks, movement time, and the Fugl-Meyer Assessment (FMA). Three of four participants demonstrated significant improvements in muscle activity patterns and kinematic parameters, suggesting a potential enhancement in upper limb motor function. In particular, the training showcased promising outcomes for patients with moderate-to-severe chronic stroke hemiplegia both by activating necessary muscles and limiting compensatory movements. However, the effectiveness was not universally applicable, since one participant evidenced no appreciable improvements. This preliminary study highlights the potential of myoelectric-driven robots in rehabilitation. It sets the stage for future research to validate and further optimize this methodology for patients with stroke and motor function impairment.