What is thyroid cartilage?

Thyroid cartilage, also called the Adam's apple, is a large piece of cartilage forming most of the anterior wall of the larynx (voice box).

Anatomy

Position

The thyroid cartilage lies in the median plane of the neck on the level of C4-C5 vertebrae, just below the hyoid bone. It is superficial and can be easily palpated through the skin.

Shape and Structure

It has two quadrilateral-shaped laminae, fused in the median plane; the fusion is complete in males, whereas it is incomplete in females, forming the laryngeal prominence (Adam's apple). The lower border of the thyroid cartilage is connected by the cricothyroid ligament to the cricoid cartilage below, while its upper border is connected by the thyrohyoid ligament to the hyoid bone above.

At the posterior surface, the superior cornu is curved superiorly and posteriorly and gives attachment to the thyrohyoid muscle. On either side of the midline below the superior cornu, there is an oval facet for articulation with the arytenoid cartilage. The inferior cornu gives attachment to the lateral cricothyroid muscle.

Articulations

Thyrohyoid articulation

Cricothyroid articulation