The effectiveness of electrical stimulation therapy in promoting peripheral nerve regeneration has been fully affirmed through a large number of clinical practice. The electric field stimulated by electricity can accelerate the migration, crawling, growth and development of Schwann cells, increase the nerve growth factor secreted by the corresponding Schwann cells, and the electric field has a tendency effect on the structural protein, microfilament and microtubule of axons, which not only improves the nerve growth speed, but also enables the nerve fibers to grow into the distal end of the nerve accurately along the direction of the electric field. After nerve injury, the muscle will lose its motor function and degenerate and atrophy. Kern et al.  found that the proportion of fat and connective tissue in atrophic muscles decreased significantly after functional electrical stimulation. He believed that functional electrical stimulation can thicken and regenerate muscle fibers that have not yet atrophied, and regenerate organelles coupled with muscle contraction and excitation contraction, so as to prevent muscle atrophy. Marqueste et al.  confirmed that functional electrical stimulation can maintain a high percentage of type 2 muscle fibers in muscle. When the muscle atrophy reaches a certain degree, even if the nerve function recovers, the muscle will not contract, so we must give certain electrical stimulation in time after the muscle is denervated. Electrical stimulation is the use of current to promote the regeneration of injured peripheral nerve function and prevent denervated atrophy of skeletal muscle. At present, there are three commonly used electrical stimulation methods: surface stimulation, percutaneous stimulation and total implantation. The advantages of surface stimulation avoid the cumbersome operation of embedding electrodes in the body, the need for reoperation and the trauma caused by needle electrodes. It is convenient, painless and has a wide range of indications. At the same time, it also has no potential infection and injury caused by percutaneous stimulation. At present, the mechanism of functional electrical stimulation promoting peripheral nerve regeneration and preventing muscle atrophy is still unclear, but many studies show that electrical stimulation can indeed delay the process of muscle atrophy, reduce the loss of muscle weight, shorten the time of electrical activity of muscle motor units and spontaneous muscle contraction, accelerate the speed of axon regeneration and shorten the time of muscle denervation, Improve the quality of motor function recovery after muscle reinnervation.
Although surface electrical stimulation is an effective treatment for the recovery of nerve function, 6 cases in this group can not recover completely. In addition to the degree of original injury and the method of surgical repair, the intensity, location, time and method of surface electrical stimulation are the influencing factors. Due to the limited stimulation intensity (patients with higher stimulation intensity will feel uncomfortable and have the possibility of skin scald), the interval between two stimuli is too long (because the surface stimulation treatment is carried out in the hospital), the poor compliance of patients after three courses of treatment and other factors will affect the curative effect. Therefore, in practice, we should make our own individualized treatment plan.
In short, early transcutaneous neuromuscular electrical stimulation can improve the local blood circulation of damaged nerves, improve the excitability of neuromuscles, enhance muscle coordination, prevent muscle atrophy and promote the regeneration of peripheral nerves.