Development of a gait re-education system in incomplete spinal cord injury.

OBJECTIVE The aim of the paper is to present the development of a system for swing phase restoration in patients with incomplete spinal cord injury. METHODS The functional electrical stimulation based gait re-education system comprises a sensory system, a system providing cognitive feedback and a motor augmentation system facilitating and correcting the movement of the swinging extremity. Mathematical algorithms estimate swing quality and classify the swing phase of walking into 3 levels, termed cognitive feedback, which is provided to the patient as an auditory signal. A single-channel peroneal functional electrical stimulation was applied as a motor augmentation system to provide the patient with the motor assistance required. The important novelty of the proposed system is that motor assistance is provided only at the level that enables the patient to perform a good swing. RESULTS The developed system was tested in a patient with incomplete spinal cord injury, with C4-5 lesion, whilst walking on a treadmill. The results show that the automated sensory-driven functional electrical stimulation augmentation system, providing only the minimal assistance required based on the subject's performance, is a viable approach that successfully releases a therapist from the task of delivering properly timed stimulation of adequate intensity in assisting the swing phase of walking.