Electrostimulation of the median nerve in tetraplegics by means of implanted stimulators.

Since 1971 we studied on the possibility of utilization of implanted stimulators in tetraplegics caused by spinal cord injury of the cervical segment. Restoration to tetraplegic patients of the ability to perform some grasping functions of the hand may make them recover some independence and reduce the degree of disability. The examination conducted so far supplied much valuable information regarding reactions of a neuromuscular system at implanted stimulators as well the influence of systematic stimulation training on functions of the hand. This was not observed by other authors using transcutaneous stimulation. The examinations we performed revealed a several-fold increase in the force and prolongation of the period of maintenance of the maximal moment developed by the stimulation as well as the result of the stimulation training. Another observation we made was the possibility of active influence of the patient on the stimulation results. It consists in the possibility of active increase by the patient of the value of forces developed by the stimulated, previously paralysed muscles. The effect on the stimulation level, and on the extent of the "stimulation base" was found. The effect of active "support" of stimulation by the patient is the more effective, the lower the stimulation base is. We believe that our observations may have practical significance. Perfection of control over the stimulators' activity from inner sources will probably permit in many instances to utilize functionally tetraplegics' paralysed hand.