Where does the external branch of the superior laryngeal nerve travel?

The external branch of the superior laryngeal nerve is primarily responsible for innervating the cricothyroid muscle, which plays a crucial role in modulating tension on the vocal cords. This nerve branches from the superior laryngeal nerve, which itself is a branch of the vagus nerve (CN X).

The accurate pathway of the external branch is that it travels along the inferior constrictor muscle of the pharynx while accompanying the superior thyroid artery. This anatomical course is important as it shows the relationship between the nerve and the artery, which is useful during thyroid and neck surgeries to prevent injury to both the nerve and the blood supply.

Understanding this pathway helps clinicians and surgeons locate the external branch of the superior laryngeal nerve, especially in procedures involving the thyroid gland, as inadvertent damage to this nerve can lead to voice problems.