A soft supernumerary hand for rehabilitation in sub-acute stroke: a pilot study on spasticity

In sub-acute stroke patients, task-specific training is the most effective rehabilitation treatment for the upper limb. However, in those patients with severe paresis and initial spasticity, task-specific training could increase the risk to develop severe spasticity in the following months. Four sub-acute patients, at high risk of developing spasticity, underwent task-specific training using a supernumerary, aesthetically and functionally anthropomorphic, soft robotic hand (SoftHand-X), driven by the residual movements of the patient's paretic hand. A 1-year follow up was done. All subjects presented a remarkable recovery of upper limb function. No worsening of spasticity was found. The proposed SoftHand-X-based rehabilitation technique for task-specific training in sub-acute stroke patients does not increase the risk of developing severe spasticity.