General Medical Information

Larynx

Susan D. John
Michael D. Maves

The major structural elements of the larynx are the shield-shaped thyroid cartilage and cricoid cartilages. They join through the cricothyroid joint. The superior cornua of the thyroid ala articulate through several small cartilages with the hyoid bone. Overlying the structure of this skeletal framework are the infrahyoid muscles, which include the paired sternohyoid, sternothyroid, omohyoid, and thyrohyoid muscles.

The epiglottis is formed of fibroelastic cartilage and has multiple perforations that allow free access of lymphatic drainage or tumor to the preepiglottic space. The preepiglottic space is a C-shaped space bounded superiorly by the median glossoepiglottic ligament, inferiorly by the thyroid cartilage, anteriorly by the thyrohyoid membrane, and posterolaterally by the epiglottis and aryepiglottic folds. Free dissemination of tumor can occur within the preepiglottic space. The paired arytenoid cartilages provide an attachment for the vocal ligament and movement of the vocal folds. The intrinsic muscles of the larynx are innervated by the recurrent laryngeal nerve. The exception is the cricothyroid muscle, which is innervated by the superior laryngeal nerve. The recurrent laryngeal nerve enters inferiorly and laterally to the cricothyroid articulation through the Killian-Jamieson area. The recurrent laryngeal nerve on the left originates over the aortic arch and ascends in the neck to innervate the larynx. On the right, this structure goes around the subclavian artery.