Interarytenoid

Interarytenoid refers to a group of intrinsic laryngeal muscles located on the posterior aspect of the larynx that connect the arytenoid cartilages. The interarytenoid muscle group consists of the transverse interarytenoid and the oblique interarytenoid muscles, which together contribute to glottic closure and vocal function.

Anatomy and relationships: The transverse interarytenoid muscle runs horizontally between the posterior surfaces of the two arytenoid cartilages. The oblique interarytenoid muscles originate near the base or muscular processes of one arytenoid and insert into the apex of the opposite arytenoid, forming an oblique, crossing arrangement. These muscles lie behind the vocal folds, forming part of the posterior wall of the glottis and helping to create a tight posterior glottic seal during phonation and swallowing.

Function: The primary action of the interarytenoid muscles is to adduct the arytenoid cartilages, bringing the vocal folds closer together and closing the posterior portion of the glottis. This action is essential for efficient voice production and for protecting the airway during swallowing.

Nerve supply: The interarytenoid muscles are innervated by the inferior laryngeal nerve, a branch of the recurrent laryngeal nerve from the vagus nerve.

Clinical significance: Proper function of the interarytenoid muscles supports normal voice quality by enabling complete glottic closure. Dysfunction or paralysis, often due to recurrent laryngeal nerve injury, can impair glottic adduction, leading to breathy voice and increased risk of aspiration. In clinical practice, these muscles are recognized as key components of posterior glottic mechanics and may be considered in laryngeal surgery and diagnostic assessments.