Orthoses and Electrical Stimulation for Walking in Complete Paraplegia

Abstract

Orthotic systems, orthoses combined with functional neuromuscular stimulation (FNS), and FNS systems alone, are compared for their safety, function, and ease of use as walking systems for people with complete paraplegia. Despite the safety and joint protection offered by orthoses, the majority of paraplegics with lesions above the T-1 2 level discard braces at the termination of the rehabilitation period. Reasons include the limited function provided, poor cosmetic appearance, and high energy cost of use. Conventional bracing has been combined with FNS to facilitate the swing phase of gait, but the disadvantages of braces are still present; the advantage of slightly reduced energy cost with FNS is offset by the drawback of increased complexity. Trials of both surface and percutaneous FNS systems have demonstrated that FNS walking for paraplegics is feasible in the research environment. While pure FNS systems eliminate the disadvantages of bracing, they have the requirements of complex electrode application in the case of surface systems, or care of electrode skin sites and connections in the case of percutaneous systems. Additional problems of FNS systems are a high energy cost and lack of trunk and hip stability, requiring the use of a walker. The authors are addressing these problems through the development of closed-loop control of stimulation to utilize muscles in more normal on/off cycles and in the development of totally implanted systems to increase reliability and convenience.

Longitudinal Performance of a Surgically Implanted Neuroprosthesis for Lower-Extremity Exercise, Standing, and Transfers After Spinal Cord Injury

“…If the neurological damage from SCI is confined to upper motor neurons, then intact peripheral nerves can be excited with small electric currents, causing contractions of the muscle fibers they innervate. By coordinating the actions of a number of muscles to produce useful movements from the otherwise paralyzed limb, FES technology can provide individuals paralyzed by thoracic or low cervical spinal cord injuries with the ability to exercise, stand, and transfer 5, 6, 7 . Neuroprostheses can allow their users to circumvent environmental barriers and increase the ability to participate in meaningful activities 8, 9, 10, 11 , facilitate tasks that were previously difficult or impossible from the wheelchair, and improve the health, self-image, and sense of well-being of persons with paralysis 12, 13, 14 .…”

Neuromuscular electrical stimulation in neurorehabilitation

“…These systems are fitted to patients with complete or incomplete paraplegia. 146,197,265,266 One design combines a Louisiana State University Reciprocating Gait Orthosis (LSU-RGO) with a 4-channel transcutaneous stimulator and a flexible copolymer electrode cuff. Follow-up studies on RGO-based hybrid orthoses show that up to 41% of system recipients use it for gait 101 and 66% use it for exercise.…”

New Frontiers in SCI Rehabilitation

“…Standing and stepping have been improved with functional electrical stimulation (FES), but the energy cost has been great. FES alone and combined with one of the models of an RGO, HGO, or other assistive and bracing devices can allow walking as an exercise and in some instances permit stepping over indoor distances (26,27). Surface or implanted electrodes are used in the quadriceps for hip flexion and to help stand up, and, depending on the system, also over the hamstrings, glutei, and ankle dorsiflexors.…”