Functional Electric Stimulation (FES)
Healthy muscle function consists of a contraction phase and a relaxation phase. When a muscle is not functioning properly, one of these responses is typically absent or shortened - this is interpreted as "spasm". Furthermore, injured muscle contains muscle fibers that are held in a firm, contracted state to protect the muscle from being over used and causing further injury - this is interpreted as a “knot” in the muscle.
The goal of FES is to replicate the body’s own natural functions by stimulating the cyclic activity of muscle contraction and relaxation, thereby returning the muscle to a more normal functioning pattern.
FES was first used many decades ago in the rehabilitation of human spinal cord injury patients to generate muscle movement and prevent atrophy. There have since been multiple human studies that have shown the ability of FES to reverse muscle atrophy for denervated muscle tissue to obtain standing and walking in spinal cord injury patients. Today, FES has been shown to be effective for multiple purposes including the treatment of both spastic and flaccid muscle.