Myoelectric control of an implanted neuroprosthesis to restore gait in incomplete spinal cord injury

Functional electrical stimulation can be used to restore gait after incomplete spinal cord injury but needs to be coordinated with the user´s retained volitional control. This paper outlines the case study of an implanted neuroprosthesis comparing an open-loop, pre-set pattern of stimulation with use of intramuscular electromyogram (EMG) recordings to trigger changes in stimulation. The user could modulate walking speed with the EMG control between 0.20 and 0.48 m/s by altering the amount of time spent in double support, while velocity was maintained at 0.31 m/s without the EMG control. Further investigation is warranted, but this preliminary finding demonstrates that the EMG control should allow users to modulate speed to walk faster in open spaces or slow down to navigate confined areas.