The uses of lower limb exoskeleton, functional electrical stimulation, and future improvements for leg paralysis management - A systematic review

Introduction: Ambulatory disability is one of the causes of depression and decreased quality of life. The common treatments used by patients are wheelchair, walker, forearm crutches, or immobilization in their house. Other orthoses such as knee ankle foot orthosis (KAFO) is very useful in certain conditions. Replacement therapy with a lower limb exoskeleton may increase the quality of life. The current review aims to evaluate the lower limb exoskeleton with or without functional electrical stimulation (FES) in assisting mobility in paraplegic patients. Methods: A search was performed to identify studies that compared lower limb exoskeleton to KAFO or hybrid exoskeleton with FES in paraplegic patients. Three publications were identified, with subjects ranging from 1 to 3 presenting with spinal injuries between T6 to T10. The measured parameters were locomotion ability, exoskeleton motor power, and torque. Results: The single-use of lower limb exoskeleton in paraplegia patients resulted in 15 sec faster (96s) Timed Up Go (TUG) test, 38 seconds faster (58s) 10-meter walked test (10MWT), and a 27 m farther 6-minute walked test (6MWT) compared to KAFO. The combination of exoskeleton with functional electrical stimulation (FES) reduces muscle fatigue and prevents muscle atrophy by providing stimulus to the muscle that imitates physiological stimulation by nerves. Discussion: Exoskeleton may assist disabled individuals in performing daily routine activity by improving gait, lessening exertion, and thus increasing the quality of life. Further improvement to exoskeleton devices includes integration with FES. Exoskeleton fit on the user also needs to be adjusted to user age and leg dimension to optimize movement and quality of life.