Muscle
Arytenoid muscles (transverse and oblique)
Muscles linking the two arytenoid cartilages
High-yield
Interarytenoid activity helps close the posterior, intercartilaginous glottis. It works with the lateral cricoarytenoids, whose strongest closing effect is on the membranous vocal folds.
Overview
Behind the arytenoids, transverse fibers cross the midline and oblique fibers run diagonally between the cartilages. The transverse part is unpaired. Their contraction brings the arytenoids closer together; some oblique fibers continue toward the epiglottis and help narrow the laryngeal entrance.
Reference facts
- Origin
- Transverse fibers: posterior arytenoid surface. Oblique fibers: near the muscular process of an arytenoid.
- Insertion
- Transverse fibers reach the opposite posterior surface. Oblique fibers cross toward the opposite apex, with an aryepiglottic continuation in some fibers.
- Innervation
- Main motor supply from both recurrent laryngeal nerves, branches of CN X; communicating laryngeal nerve fibers also occur.
- Action
- Draw the arytenoids together and support posterior glottic closure. Oblique fibers continuing into the aryepiglottic folds assist inlet narrowing.
- Blood supply
- Laryngeal branches of the thyroid arterial system, especially the superior laryngeal artery, with anastomotic contributions.
Clinical correlation
Incomplete glottic closure can contribute to a breathy voice, but a small posterior gap is also seen in people with normal voices. Its appearance on examination does not by itself establish interarytenoid weakness.
Frequently asked questions
What do the arytenoid muscles (transverse and oblique) do?
Draw the arytenoids together and support posterior glottic closure. Oblique fibers continuing into the aryepiglottic folds assist inlet narrowing.
What nerve innervates the arytenoid muscles (transverse and oblique)?
Main motor supply from both recurrent laryngeal nerves, branches of CN X; communicating laryngeal nerve fibers also occur.
Where do the arytenoid muscles (transverse and oblique) attach?
Origin: Transverse fibers: posterior arytenoid surface. Oblique fibers: near the muscular process of an arytenoid. Insertion: Transverse fibers reach the opposite posterior surface. Oblique fibers cross toward the opposite apex, with an aryepiglottic continuation in some fibers.
What is the blood supply of the arytenoid muscles (transverse and oblique)?
Laryngeal branches of the thyroid arterial system, especially the superior laryngeal artery, with anastomotic contributions.