Thyroid cartilage

The thyroid cartilage is the largest of the nine cartilages that make up the laryngeal skeleton, the cartilage structure in and around the trachea that contains the larynx.

Additional recommended knowledge

Essential Laboratory Skills Guide

Daily Sensitivity Test

Correct Test Weight Handling Guide: 12 Practical Tips

Structure

It is composed of two plate-like laminae that come together on the anterior side of the cartilage to form a peak, called the laryngeal prominence. This prominence is often referred to as the "Adam's apple". The laryngeal prominence is obvious in both sexes, but it tends to be somewhat more robust in the adult male.

The lip of the thyroid cartilage just superior to the laryngeal prominence is called the thyroid notch or superior thyroid notch.

Layers and articulations

The two laminae that make up the main lateral, surfaces of the thyroid cartilage extend obliquely to cover either side of the trachea. The oblique line marks the superior lateral borders of the thyroid gland.

The posterior edge of each lamina articulates with the cricoid cartilage inferiorly at a joint called the cricothyroid joint.

Movement of the cartilage at this joint produces a change in tension at the vocal folds, which in turn produces variation in voice.

The entire superior edge of the thyroid cartilage is attached to the hyoid bone by the hyothyroid membrane.

Function

The thyroid cartilage forms the bulk of the anterior wall of the larynx, and serves to protect the vocal folds ("vocal cords") which are located directly behind it.

It also serves as an attachment for several laryngeal muscles.

Additional images