Terminal Branch of Recurrent Human Laryngeal Nerve

The importance of the recurrent laryngeal nerve in surgery on the anterior region of the neck has motivated many published papers on critical points of its pathway, relationship with the inferior thyroid artery, penetration in the larynx, division outside the larynx, and branches communicating with the internal branch of the superior laryngeal nerve. We analyze the terminal branches of the recurrent laryngeal nerve and their distribution through the laryngeal muscles. 44 laryngeal nerves had been dissected. Most frequently, the recurrent laryngeal nerve presents a division below or at the level of the lower margin of the cricoid cartilage (outside the larynx). One of these branches forms the communication with the internal branch of the superior laryngeal nerve, and the other penetrates the laryngeal space. Above the lower margin of the cricoid cartilage, the inferior laryngeal nerve issues a variable number of branches to muscles (3 to 7): to the posterior cricoarytenoid muscle; to the oblique and transversal arytenoid muscles; and to the lateral cricoarytenoid muscle and the thyroarytenoid muscle. 1. Introduction The anatomy of the recurrent laryngeal nerve is important in medical practice applications [1] and surgery [2, 3]. Nerve injuries may occur in interventions performed on the anterior cervical region [4, 5], particularly during thyroidectomy [6–12] or parathyroidectomy [13–15]. Such injuries result in speech, breathing, and swallowing disorders [16], causing health and behavioral disorders. Because of its variability, it is increasingly important knowing the anatomy of the recurrent laryngeal nerve [14, 17–19]. One controversial matter hotly debated by scientists and anatomists [3] concerns the levels at which nerve divisions occur [20–27], along with the nature [10, 19, 28–30] and destination of such branches [22, 31, 32]. Clarification of such issues is essential, since the clinical picture varies according to the injured branch [33]. Despite awareness of the importance of studying this nerve, anatomists and surgeons confront with controversies and doubts [17, 30, 34–36] in the literature available. Better understanding of the anatomy of the recurrent laryngeal nerve and its terminal branches would also help fit the basis for establishing techniques for reinnervation of the larynx following recurrent laryngeal nerve injury [4, 37, 38]. The objective of the research is to analyze the terminal branches of the recurrent laryngeal nerve and its distribution among the muscles of the larynx. Our hypothesis is as recurrent laryngeal nerve has great