Experience with a hand grasp neuroprosthesis incorporating natural sensory feedback

This paper presents experience with a hand grasp neuroprosthesis that is controlled by means of signals from natural sensors in the skin. The signals from the natural sensors were recorded with a cuff electrode implanted around the palmar digital nerve innervating the radial aspect of the index finger. The implanted muscle stimulator is part of the commercial FREEHAND® System. A data-recording unit allowed storage and off-line analysis of the stimulator command and the recorded nerve signal. The system was used by a tetraplegic volunteer to test the feasibility of including natural sensors in a hand grasp neuroprosthesis for activities of daily living.