inferior pharyngeal constrictor function

The inferior laryngeal nerves are the endpoint of the recurrent laryngeal nerves, which have an interesting course. Inferior to the vocal cords, sensory innervation is all provided by the recurrent laryngeal nerves.

This nerve is the principal motor supply to vocal production. They continue their course superiorly, posterior to the cricothyroid joint, to enter the larynx. Once in the larynx, the recurrent laryngeal nerve is referred to as the inferior laryngeal nerve, innervating all the intrinsic musculature of the larynx except for the cricothyroid muscle. Both recurrent laryngeal nerves travel superiorly along the lateral surface of the esophagus and trachea, coursing posterior to the thyroid lobes. The left recurrent laryngeal nerve lies inferior to the aortic arch distal to the ligamentum arteriosus. The recurrent laryngeal nerve anatomy differs depending on its laterality-the right recurrent laryngeal nerve branches from the vagus nerve in proximity to the right subclavian artery. While the internal branch of the superior laryngeal nerve pierces through the thyrohyoid membrane and carries sensory fibers that innervate the laryngeal mucosa superior to the vocal cords. The external branch of the superior laryngeal nerve follows a course with the superior thyroid vessels and contains motor fibers that innervate the cricothyroid muscle. The superior laryngeal nerve then divides into external and internal branches. The superior laryngeal nerve is a branch from the vagus nerve arising above the carotid bifurcation as it descends down the neck.

There is superior and inferior innervation, and these nerves' names reflect as much. The innervation of the larynx is similar to other areas of the body with both sensory and motor components.

Inferior pharyngeal constrictor function