Case Western Reserve University, Cleveland, OH,
Departments of Orthopedic Surgery,
Biomedical Engineering
and Mechanical and Aerospace Engineering
Eight channels of electrical stimulation and computer controlled bracing provided functional standing and walking to complete paraplegic individuals.
Six subjects with complete paraplegia (TI-TII) utilized the combination of an 8 channel radio frequency controlled and powered implantable stimulator, or a percutaneous FES system, with a low weight, functional orthosis with computer controlled joint locks. A physical therapist evaluated outcomes by utilizing standard and modified mobility assessment instruments and direct interview to determine the users function in the household or the community. A Bechman Metabolic Analyzer estimated energy consumption.
Surgical technique developments allow implantation of an 8 channel RF powered and controlled FES system in one surgical session. A prototype trunk support will automatically reduce movement constraints when not walking. The computer synchronized prototype knee joint locks. Computer simulation now exists for a hip joint which aids stair climbing and trunk stability without the RGO reciprocator. Physical therapists demonstrated that some subjects previously unable to use RGOs alone can be taught to utilize braces with FES and crutches. Sit to stand maneuvers and ambulation are also simplified with the application of FES. Subjects using this system (brace, FES & crutches) ambulated a total of 500m to 800m with 5 min rests between ten 50m walks. Energy consumption was 7 METs for short walks.
The less constrained brace with an implantable FES system appears capable of giving a complete paraplegic user a limited but acceptable level of walking.
Supported by NIH R01 Grant # NS/HD - 33287 and the Rehabilitation Research and Development Service of the Department of Veterans Affairs.
