The larynx is also called the “voice box” or the organ of speech.
-The superior part of the trachea
• It acts to hold the airway open
• Anteriorly covered by strap muscles (Infrahyoid muscles) and thyroid gland
• Adjacent to C3-C6
• Visible on the surface of the neck as the laryngeal prominence
I. Skeleton of the larynx–is composed of the cartilages (Hyaline with the exception of one) and membranes (all of it is covered with mucous membrane).
A. Cartilages of the laryngeal skeleton- 3 paired and 3 unpaired
2.Conus elasticus Lateral portion of cricothyroid ligament/membrane
Stretches up to the vocal ligament on the interior of the larynx
a. Vocal ligament (cords) thickened superior aspect of conus elasticus
- Covered by mucous membrane to create Vocal Folds
*** Vestibular fold (Immovable) is superior to the Vocal fold (Movable)
II. Chambers on the interior of the larynx- The entire larynx is covered by mucous membrane, inside and out. The mucous membrane stretches over all of the cartilages and the membranes that form the skeleton of the larynx. On the inside the folds of mucous membrane divide the larynx into chambers or regions.
Rima glottidis: Space between vocal ligaments
** See diagram for the location of the following:
1. vestibule Space above the vestibular folds
2. vestibular folds
3. ventricle Membranous out pocketing between the vestibular folds & vocal folds
4. vocal folds
5. infraglottic cavity below the vocal folds will continue as the trachea
***Areas used for descriptive purposes
III. Muscles of the larynx
A. Extrinsic—These muscle are responsible for moving the entire larynx via the hyoid.
Include infrahyoid muscles, suprahyoid muscles and muscles of the pharynx.
Action of suprahyoid muscles Elevate the hyoid/larynx
Action of infrahyoid muscles Depress the hyoid/larynx
***Epiglottis will be deflected by posterior 1/3rd of tongue as the larynx is elevated
B. Intrinsic- This is group of paired muscle which act on the vocal ligaments