Lateral cricoarytenoid muscle

The lateral cricoarytenoid muscles extend from the lateral cricoid cartilage to the ipsilateral arytenoid cartilage. By rotating the arytenoid cartilages medially, these muscles adduct the vocal cords and thereby close the rima glottidis, protecting the airway. (Their action is antagonistic to that of the posterior cricoarytenoid muscles.) The lateral cricoarytenoid muscles receive innervation from the recurrent laryngeal branch of the vagus nerve (CN X).