Muscle · Neck

Cricothyroid

Musculus cricothyroideus

The only muscle of the larynx that lies on its outside, and the only one not supplied by the recurrent laryngeal nerve — two exceptions that make it the muscle to learn first. It runs from the front of the ring-shaped cricoid cartilage up and back to the lower edge of the thyroid cartilage, and when it shortens it tilts the thyroid cartilage forward and down on the cricoid. That tilt increases the distance between the front and back attachments of the vocal folds, so the folds are stretched longer and thinner, and the pitch of the voice rises. Its action is a tilt of one cartilage on another rather than a movement at any joint of the skeleton, which is why no joint motion is listed for it.