Functional walking in paralyzed patients by means of electrical stimulation

Three partially paralyzed patients were unable to walk even after maximal rehabilitation attempts at a major rehabilitation center. One 36-year-old man had transverse myelitis, a 57-year-old man had had a stroke, and the third patient, a 35-year-old man, had incurred a traumatic brain injury. The three patients were unable to flex the hips, had adductor spasm and weak hip and knee extension, and lacked ankle dorsiflexion. Intramuscular stainless steel wire electrodes activated by timers were placed in the quadriceps, hip flexors, extensors, and abductors, as needed. Muscle force and foot contact evaluations were done using the Cybex and the Cleveland Veterans Administration Gait Laboratory. After implantation of intramuscular electrodes, all three patients had improved function but still desired some supervision in walking. A ten-fold increase in knee torque was noted in one patient, thereby providing him with nearly normal strength. No implant complications were noted. The study demonstrated the feasibility of functional neuromuscular stimulation (FNS) gait augmentation in a previously nonwalking patient outside the laboratory. Further improvements will require the development of an implantable, multichannel, programmable microprocessor-controlled stimulator.