Walking Ankle Robot for Foot Drop in Aging and Disabled Populations: A Demonstration Project

Many individuals with central nervous system (CNS) injuries (e.g., a stroke) or peripheral nervous system (PNS) injuries (e.g., peroneal nerve injury, neuropathy, radiculopathy, and/or musculoskeletal injury) that affect their ankle movement have residual impairments that affect their walking and balance. These impairments include the disability "foot drop," which increases the risk for falling.

This study will focus on PNS injuries that cause foot drop.

Current therapy to address foot drop is limited primarily to the use of ankle foot orthoses (braces) that help keep the foot from hitting the ground to prevent falling. Also, some individuals with foot drop use functional electrical stimulation to the leg nerve to lift the foot. Regardless, none of these, or other existing, methods to address foot drop cures or even improves significantly the underlying neurological deficit behind this disability. Braces improve walking safety only while they are worn, and functional electrical stimulation does not work when it is turned off, or when the nerve has been severely damaged. Thus, the increased fall risk due to foot drop is generally considered life-long and incurable.

The investigators have developed a shoe-interfaced ankle robot with an adaptive control system, to assist an individual with ankle movement only as needed. Data from the investigators' previous studies on foot drop due to stroke show great promise for this ankle robot as a new rehabilitation tool for invididuals with foot drop, when used during treadmill walking. The investigators would like to utilize our findings from these stroke studies in learning how they can be used for PNS-related foot drop.