The transverse arytenoid is an intrinsic muscle of the larynx that functions primarily to adduct (bring together) the arytenoid cartilages, thereby contributing to the closure of the glottis.
Anatomical location and structure
- The muscle is positioned within the posterior part of the laryngeal cavity, spanning horizontally between the posterior surfaces of the two arytenoid cartilages.
- It is a flat, thin muscle that lies deep to the vocal cords and superficial to the posterior cricoarytenoid muscles.
- The transverse arytenoid is part of the “interarytenoid” muscle group, which also includes the oblique arytenoid muscles.
Origin and insertion
- Origin: Posterior surfaces of the arytenoid cartilages.
- Insertion: Opposite posterior surface of the contralateral arytenoid cartilage, forming a single muscular band that connects the two cartilages.
Innervation
- The muscle receives motor innervation from the recurrent laryngeal branch of the vagus nerve (cranial nerve X).
Vascular supply
- Blood is supplied by branches of the superior thyroid artery and the cricothyroid artery.
Function
- By pulling the arytenoid cartilages together, the transverse arytenoid narrows the rima glottidis, facilitating phonation and protecting the lower airway during swallowing.
- It works synergistically with the oblique arytenoid muscles and the lateral cricoarytenoid muscles to achieve complete glottic closure.
Clinical relevance
- Paralysis or dysfunction of the recurrent laryngeal nerve can impair the transverse arytenoid, leading to vocal fold paresis, hoarseness, or an increased risk of aspiration.
- Surgical procedures on the larynx, such as medialization thyroplasty, consider the integrity and tension of the transverse arytenoid to restore adequate glottic closure.
Comparative anatomy
- The transverse arytenoid is present in most mammals, reflecting its essential role in voice production and airway protection across species.
References
- Standring, S. (Ed.). (2022). Gray’s Anatomy: The Anatomical Basis of Clinical Practice (43rd ed.). Elsevier.
- Patel, R. & J. L. Brown. (2020). “Intrinsic laryngeal muscles: anatomy, function, and clinical implications.” Journal of Voice, 34(5), 657‑666.
