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Origin posterior part of the cricoid Insertion muscular process of the arytenoid cartilage Nerve recurrent laryngeal nerve branch of the vagus Actions abducts and laterally rotates the cartilage, pulling the vocal ligaments away from the midline and forward and so opening the rima glottidis Antagonist Lateral cricoarytenoid muscle Latin Musculus cricoarytaenoideus posterior | ||
The posterior cricoarytenoid muscles are small, paired muscles that extend from the posterior cricoid cartilage to the arytenoid cartilages in the larynx.
Contents
Innervation
The posterior cricoarytenoid muscles receive innervation from the recurrent laryngeal branch of the vagus nerve.
Function
The posterior cricoarytenoid muscles are the only muscles to open the vocal cords. By rotating the arytenoid cartilages laterally, these muscles abduct the vocal cords and thereby open the rima glottidis. Their action opposes the lateral cricoarytenoid muscles.
Clinical significance
Paralysis of the posterior cricoarytenoid muscles may lead to asphyxiation as they are the only laryngeal muscles to open the true vocal folds, allowing inspiration and expiration.
References
Posterior cricoarytenoid muscle Wikipedia(Text) CC BY-SA