A functional electrical stimulation exercise system designed to increase bone density in spinal cord injured individuals

A prototype exercise system that uses computerized electrical stimulation to control muscular movements has been developed. The system incorporates a biomechanical stimulus that stimulated an osteogenic response in an animal model. The purpose of this development was to increase the bone strength of spinal cord injured people, in order to reduce the high rate of spontaneous fractures, and the expected increased rate of fractures when walking with functional electrical stimulation (FES) systems is attempted. The mechanical stimulus the user experiences is modeled after gait analysis experiments, which measured the force profile during walking. The mechanical stimulus occurs when the foot experiences a rapid increase in resistance, produced by a hydropneumatic system that incorporates an electrical proportional valve, controlled by a single board computer system. The computer system has a user friendly character display and keypad interface. The user can set the parameters for the impact force, the electrical stimulus ramp rate to the muscles, the maximum current, and the exercise time period