External laryngeal nerve

External laryngeal nerve
File:Gray793.png Course and distribution of the glossopharyngeal, vagus, and accessory nerves. (External branch of superior laryngeal labeled at center right.)
Details
Latin	ramus externus nervi laryngei superioris
From	superior laryngeal nerve
Innervates	cricothyroid muscle, pharyngeal plexus
Identifiers
Dorlands /Elsevier	r_02/12690066
TA
TH	{{#property:P1694}}
TE	{{#property:P1693}}
FMA	{{#property:P1402}}
Anatomical terms of neuroanatomy [[[d:|edit on Wikidata]]]

The external laryngeal nerve is the smaller, external branch (ramus externus) of the superior laryngeal nerve. It descends on the larynx, beneath the sternothyroid muscle, to supply the cricothyroid muscle.

It functions to tense the vocal cords by activating the cricothyroid muscle, increasing pitch.

It gives branches to the pharyngeal plexus and the superior portion of the inferior pharyngeal constrictor, and communicates with the superior cardiac nerve behind the common carotid artery.

Clinical significance

The external branch is susceptible to damage during thyroidectomy or cricothyrotomy, as it lies immediately deep to the superior thyroid artery. The ability to produce pitched sounds is then impaired along with easy voice fatigability, (usually mono-toned voice). Damage to the superior laryngeal nerve leaves the vocal cord abducted and poses an aspiration risk.

External links

• 1328873530 at GPnotebook
• Overview at sprojects.mmi.mcgill.ca
• cranialnerves at The Anatomy Lesson by Wesley Norman (Georgetown University) (X)