Arytenoid muscle

The Arytenoid is a single muscle, filling up the posterior concave surfaces of the arytenoid cartilages.

It arises from the posterior surface and lateral border of one arytenoid cartilage, and is inserted into the corresponding parts of the opposite cartilage.

It consists of oblique and transverse parts.


 * The Arytænoideus obliquus, the more superficial, forms two fasciculi, which pass from the base of one cartilage to the apex of the opposite one, and therefore cross each other like the limbs of the letter X; a few fibers are continued around the lateral margin of the cartilage, and are prolonged into the aryepiglottic fold; they are sometimes described as a separate muscle, the Aryepiglotticus.


 * The Arytænoideus transversus crosses transversely between the two cartilages.

Action
The Arytœnoideus approximates the arytenoid cartilages, and thus closes the opening of the glottis, especially at its back part.