The larynx is located within the anterior aspect of the neck, anterior to the inferior portion of the pharynx and superior to the trachea. Its primary function is to protect the lower airway by closing abruptly upon mechanical stimulation, thereby halting respiration and preventing the entry of foreign matter into the airway. Other functions of the larynx include the production of sound (phonation), coughing, the Valsalva maneuver, and control of ventilation, and acting as a sensory organ.

The larynx is composed of 3 large, unpaired cartilages (cricoid, thyroid, epiglottis); 3 pairs of smaller cartilages (arytenoids, corniculate, cuneiform); and a number of intrinsic muscles (see the image and video below). The hyoid bone, while technically not part of the larynx, provides muscular attachments from above that aid in laryngeal motion

Anatomical Structure

The larynx is formed by a cartilaginous skeleton, which is held together by ligaments and membranes. The laryngeal muscles act to move the components of the larynx for phonation and breathing. More information about each of these structures can be found in their respective sections.

Anatomically, the internal cavity of the larynx can be divided into three sections:

  • Supraglottis – From the inferior surface of the epiglottis to the vestibular folds (false vocal cords).
  • Glottis – Contains vocal cords and 1cm below them. The opening between the vocal cords is known as rima glottidis, the size of which is altered by the muscles of phonation.
  • Subglottis – From inferior border of the glottis to the inferior border of the cricoid cartilage.

The interior surface of the larynx is lined by pseudostratified ciliated columnar epithelium. An important exception to this is the true vocal cords, which are lined by a stratified squamous epithelium.

Image courtesy of NCI

Vasculature

The arterial supply to the larynx is via the superior and inferior laryngeal arteries:

  • Superior laryngeal artery – a branch of the superior thyroid artery (derived from the external carotid). It follows the internal branch of the superior laryngeal nerve into the larynx.
  • Inferior laryngeal artery –  a branch of the inferior thyroid artery (derived from the thyrocervical trunk). It follows the recurrent laryngeal nerve into the larynx.

Venous drainage is by the superior and inferior laryngeal veins. The superior laryngeal vein drains to the internal jugular vein via the superior thyroid, whereas the inferior laryngeal vein drains to the left brachiocephalic vein via the inferior thyroid vein.

Innervation

The larynx receives both motor and sensory innervation via branches of the vagus nerve:

  • Recurrent laryngeal nerve – provides sensory innervation to the infraglottis, and motor innervation to all the internal muscles of larynx (except the cricothyroid).
  • Superior laryngeal nerve – the internal branch provides sensory innervation to the supraglottis, and the external branch provides motor innervation to the cricothyroid muscle.
Medika Life

Medika Life is a digital Health Publication for both the medical profession and the public. Make informed decisions about your health and stay up to date with the latest developments and technological advances in the fields of medicine.

Recent Posts

SUICIDE: IS AI RESPONSIBLE?

The Raines discovered their son Adam in the closet where he hung himself with the…

2 days ago

Beds, Forests and the Price of Credibility at COP30

On a damp, equatorial morning in Belém, the river smells faintly of diesel and guava. Vendors…

2 days ago

Inside the High-Stakes Battle Over Vaccine Injury Compensation, Autism, and Public Trust

[Reprinted with permission from KFF Health News. Authored by Céline Gounder] Department of Health and…

2 days ago

Kill the Oceans and Destroy Your Health Slowly

We often picture climate change as raging wildfires, melting ice, or violent storms. But one…

2 days ago

Ukraine: Worn Hearts, Steeled Resolve

I have traveled to Ukraine nearly 20 times. Each visit deepens my respect for how…

2 weeks ago

Medicaid at a Crossroads: Safe AI, Shifting Policy and the Stakes for People’s Health

Medicaid is one of America’s most complex and essential Federal health programs, serving more than…

4 weeks ago

This website uses cookies. Your continued use of the site is subject to the acceptance of these cookies. Please refer to our Privacy Policy for more information.

Read More