| Functional neuromuscular stimulation (FNS) has been proposed as a potential therapy for restoring activity to a denervated muscle. FNS provides an innovative treatment in the management of patients with laryngeal paralysis. The injury of recurrent laryngeal nerve is relatively frequent clinically. The incidence of long-standing laryngeal paralysis is about 3%. The primary symptom of unilateral laryngeal paralysis is dysphonia. Clinically two kinds of therapies, Injection of vocal cords and internal arytenoidopexy, were often chosen to improve the quality of voice . To rehabilitate the patients with long-standing bilateral laryngeal paralysis and allow for removal of the tracheostomy tube, lateral cordopexy, arytenoidectomy, cordotomy and tracheotomy have been proposed to widen the airway on the plane of glottis. The disadvantage of these procedures is that the widen glottis increases the susceptibility to aspiration while simultaneously decreasing of the quality of voice .In order to restore to normal laryngeal function, numerous clinicalresearch were done to seek for the possibility of reinnervation with nerve to strengthen laryngeal function by restoring the movement of vocal cord and providing an adequate airway during inspiration with allowing normal voice production and airway protection.In treatment of long-standing paralysis, successful surgical reinnervation and laryngeal function restoration might be adversely influenced by many factors. First, extensive denervation atrophy has occurred, successful reinnervation might be precluded because of irreversible muscle fibrosis and degeneration of muscle endplates. After serious nerve injury, the regenerated axon might connect to the wrong target muscle, named inappropriate reinnervation, causing synkinesis and thus impairment of function. Furthermore, in case of long-standing laryngeal immobility, the cricoarytenoid joints may become fixed, this would, of course, impede restoration of laryngeal mobility despite successful reinnervation.FNS was conceived and introduced into the field of otolaryngology by Zealear and Dedo firstly. In experiments with canines, the use of FNS could restore laryngeal mobility and prevent deinnervated posterior cricoarytenoid muscle (PCA) atrophy and fibrosis and strengthen muscles contractility. Furthermore, in experiments of neural regeneration, FNS could influence the pattern of neural regeneration by a special way. It preferentially opposed reinnervation by foreign nerve fibers, and promoted selective reinnervation by its own nerve fiber. This characteristic avoided laryngeal synkinesis caused by misdirect reinnervation. But FNS had its disadvantage too, which could repress the formation of endplate.placed on the operating table in a supine position, limbs were stabilized, head was fixed with ribbon and was maintained at medial place. Before operation, laryngoscope was used to verify the mobilization well of vocal cord. Cervical skin was shaved and prepared with povidone iodine and draped in a sterile manner. Using cervical median incision from hyoid to the plane of sternum notch, platysma and cervical band-shaped muscle were separated. Tissue was bluntly dissected along paratrachea to visualize and identify the left recurrent laryngeal nerve. Dissociate left recurrent laryngeal nerve upward till the level of thyroid cartilage and downward till the inlet of thorax, and then inferior constrictor of pharynx on the left of cervix was dissected, cricopharyngeus muscle was cut and ligated. After all those were finished, left recurrent laryngeal nerve was cut and anastomosed immediately with 10-0suture silk on the level of the second tracheal ring. Now it should be sure that left voice cord was immobile. Then the stimulating electrode was laterally implanted in the left PCA. Nerve stimulating electrode was fixed together with left recurrent laryngeal nerve 2cm under the level of the second tracheal ring with silicon ring. Electrode wires were buried subcutaneously and the end of these electrod...
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