A Case Study Approach: Walking Assist Scheme Exploiting Somatic Reflex of a Leg-Paralysis Patient
Kojiro Matsushita, Akihiro Yamakawa, Hiroshi Yokoi,
and Tamio Arai
Department of Precision Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
We propose a walking-assist scheme that exploits residual functions of a hemiplegic patient with a unique case of leg paralysis – involving the somatic reflex that prevented her from raising her left leg, leaving it to drag on the ground instead. She prevented this by pressing a specific spot on her leg with her fingers. We measured electromyographic (EMG) signals and found that although she could not voluntary activate her thigh and tibial muscle, mechanical stimulus activates them. We concluded that her paralysis was a unique somatic reflex of her nerve system and we developed a mechanical stimulator that she used to train her muscles in walking and improved her gait to approach that of an unparalyzed person.
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