Visual Biofeedback of Force Information for Eccentric Training of Hemiplegic Patients

Motor learning issues for hemiplegics not only include motor impairments such as spastic paralysis, but reportedly also an inability to appropriately recognize somatic sensations. In this regard, biofeedback of movement information through visual information and auditory information has been found effective as a method for drawing attention to appropriate somatic sensations. In this context, here, we propose a novel eccentric training system utilizing visual biofeedback of force information. We first develop a compact and highly portable rehabilitation robot for home use. The robot estimates the force on the tiptoe without the use of a force sensor, and a display connected to the robot presents the force information to the trainee. Clinical trials with two chronic hemiplegics have been conducted. The results show that the timed up and go tests of both trainees are shortened after training twice a week for three weeks (six times in total). Simultaneously, the co-contraction index scores of the tibialis anterior and gastrocnemius muscles decrease. These findings in conjunction with previous results suggest that training with visual biofeedback of force information may enhance reciprocal inhibition of the tibialis anterior muscle and reduces co-contraction.