Cricothyroid muscle

The cricothyroid muscle (Cricothyroideus) is a muscle of the larynx; even, triangular, with superior vertex. It is inserted, below, on the anterior face of the cricoid cartilage; above, on the lower edge and on the anterior and posterior surfaces of the thyroid cartilage.

Innervated by the external branch of the superior laryngeal nerve, branch of the cranial nerve X, or vagus nerve, is the only laryngeal muscle innervated by this branch of the vagus nerve. It is supplied by the external laryngeal artery (or cricothyroid branch), a branch of the superior thyroid.

Function

This muscle rotates the thyroid cartilage forward and downward over the cricothyroid joint. It is the tensor of the vocal cords.