The lateral cricoarytenoid is the primary vocal cord adductor, rotating the arytenoid cartilage to bring the vocal process medially and close the glottis for phonation and airway protection during swallowing. It works in direct antagonism with the posterior cricoarytenoid abductor. The coordinated adduction of both vocal cords for glottic closure is critical for the protective laryngeal closure reflex that prevents aspiration.
| Origin | Superior border of the cricoid arch |
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| Insertion | Muscular process of the arytenoid cartilage |
| Nerve Supply | Recurrent laryngeal nerve (CN X) |
| Blood Supply | Superior laryngeal artery |
| Actions | Adducts the vocal cords (closes the glottis for phonation and airway protection); Works with the thyroarytenoid and interarytenoid muscles to close the glottis during swallowing |
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During swallowing the lateral cricoarytenoid, thyroarytenoid, and interarytenoid muscles produce the three-level glottic closure (true cords, false cords, and aryepiglottic folds) that prevents aspiration of the food bolus into the trachea.
Glottic closure weakness from lateral cricoarytenoid and thyroarytenoid palsy in unilateral RLN injury produces aspiration risk from incomplete laryngeal protection during swallowing, in addition to the breathy voice. Posterior cordotomy for bilateral vocal cord palsy must balance the competing requirements of glottic opening (for breathing) against glottic closure (for swallowing protection and voice).
Not externally palpable. Laryngoscopy demonstrates adductor function.
Lateral cricoarytenoid paralysis from RLN injury producing incomplete vocal fold adduction, causing breathy voice and aspiration risk managed with vocal fold augmentation.
