A soft robotic sock device for ankle rehabilitation and prevention of deep vein thrombosis

Abstract

We present a soft robotic sock device developed to provide robotic assistance in ankle dorsiflexion and plantarflexion of stroke patients who are at high risk of developing deep vein thrombosis. The actuators extend when infused with pressurized air, so as to guide the ankle into plantarflexion motion. On the other hand, the actuators contract back to their initial length when deflated to pull the ankle into dorsiflexion. In this work, the actuators were characterized in terms of their linear displacement-pressure relationship at zero strain as well as force-pressure relationship at 100% strain. The device was also evaluated on stroke patients, together with conventional intermittent pneumatic calf pump, whereby the femoral venous profile of the ipsilateral limb was compared using Ultrasound Doppler. Preliminary clinical trial data showed that the soft robotic sock device was able to increase the superficial femoral vein flow velocity of the ipsilateral limb, which is likely to reduce the risk of developing deep vein thrombosis.