Transverse arytenoid

The transverse arytenoid is an unpaired intrinsic muscle of the larynx. It is situated deep to the two oblique arytenoids; the oblique and transverse arytenoids are often considered two parts of a single muscle - the interarytenoid (arytenoid) muscle (which is then said to have an oblique part and a transverse part).

The transverse arytenoid bridges the gap between the two arytenoid cartilage in the larynx, occupying the concavity of the lateral surface of each cartilage.

Attachments
The muscle attaches to both arytenoid cartilages, attaching onto each cartilage at the posterior aspect of its muscular process and the adjacent lateral border of the cartilage.

Innervation
The muscle receives motor innervation from the two recurrent laryngeal nerves (each being a branch of the ipsilateral vagus nerve (CN X)); the muscle also receives branches from the internal laryngeal branch, though the latter's contribution to the muscle's motor innervation is unclear.

Function
The muscle approximates the two arytenoid cartilages to close the posterior (intercartilaginous) part of rima glottidis.