Human laryngeal reinnervation

Abstract

Bilateral vocal cord paralysis is fortunately an uncommon occurrence although the incidence of this injury secondary to external neck trauma is increasing. In general, a patient with this lesion is faced with the choice between adequate airway at the expense of a breathy, weak voice or a fairly good voice with the need for a permanent tracheotomy. In an effort to provide a better solution to this dilemma, an attempt has been made to develop a means of reinnervation of at least one vocal cord without the problems inherent in the usual nerve anastomosis techniques. After extensive preliminary work in dogs the nerve-muscle pedicle technique for reinnervation has been developed. In this procedure the branch of the ansa hypoglossi to the anterior belly of the omohyoid is mobilized and a small block of muscle containing the terminal branches is freed from the muscle proper. Using an approach similar to the Woodman arytenoidectomy, the posterior cricoarytenoid muscle is exposed, and its fibers are partially incised. The previously prepared nerve-muscle pedicle is sutured to it. In the first five patients subjected to this procedure, return of spontaneous abduction of the reinnervated vocal cord was noted between six and eight weeks post surgery. In no case was the voice weakened nor was there any problem with aspiration. All five patients have achieved sufficient air-way so that exercise tolerance for daily activities is adequate without a tracheotomy. The physiologic and histologic background of this technique is discussed in detail.