The larynx

Where is the larynx located in the human body?

In the anterior compartment of the neck, suspended from the hyoid bone, between C3 and C6.

What are the two openings of the larynx?

It opens into the laryngopharynx superiorly and is continuous with the trachea inferiorly.

What is the anatomical structure of the larynx primarily composed of?

A cartilaginous skeleton connected by membranes, ligaments, and muscles.

What are the three parts of the cavity of the larynx?

Lined with mucosa, extends from its superior

opening (laryngeal inlet) to the inferior border of

the cricoid cartilage which is continuous with the

the trachea

1. Vestibule - between the laryngeal inlet and the vestibular folds (false vocal cords). 2. Middle part - between the vestibular folds and the vocal folds, containing vocal cords. 3. Infraglottic space - between vocal folds and the inferior opening of the larynx.

What is the function of the epiglottis during swallowing?

It swings downward to close off the laryngeal inlet, preventing food and liquids from entering the respiratory tract.

What is the cricoid cartilage and where is it located?

It is the inferior aspect of the larynx, connected to the trachea inferiorly and attached to the thyroid cartilage via the cricothyroid ligament.

Attached to first tracheal ring

via cricotracheal ligament

What forms the laryngeal prominence, commonly known as the Adam's apple?

The thyroid cartilage, formed by the left and right lamina that join anteriorly.

What are the superior and inferior horns of the thyroid cartilage connected to?

The superior horns are connected to the greater horn of the hyoid bone via the lateral thyrohyoid ligament, while the inferior horns articulate with the cricoid cartilage.

Oblique line of thyroid cartilage

Oblique line (ridge on lateral surface of

lamina) - ends of the expand to form

superior and inferiorthyroid tubercles

Epiglottis

Attached by its stem to inner aspect of

angle formed by laminae of the thyroid

cartilage via the thyro-epiglottic

ligament in the midline

o Attached to the hyoid bone by the hyoepiglottic ligament

o Sits above the laryngeal inlet, during

swallowing, as the larynx moves up and

forward, swings downward to close off the

laryngeal inlet, preventing food and

liquids from entering the respiratory tract

Arytenoid cartilages

o Apex - articulates with a corniculate cartilage

o Base - articulates with the superior border of the cricoid cartilage

o Anterolateral surface has two depressions for attachment of the vocalis muscles and vestibular

ligament

o Vocal process - attachment for the vocal ligament

What is the function of the arytenoid cartilages in the larynx?

They serve as attachment points for the vocal ligament and muscles that control vocal cord tension.

What is the role of the corniculate cartilages?

They articulate with the apices of the arytenoid cartilages.

What is the role of the cuneiform cartilages?

Located within the aryepiglottic

folds, no direct attachment, but

act to strengthen the folds

What is the thyrohyoid membrane?

A tough fibro-elastic ligament between the superior margin of the thyroid cartilage and the hyoid bone.

Aperture laterally for laryngeal vessels and

nerve

What is the median thyrohyoid ligament?

An anteromedial thickening of the thyrohyoid membrane.

What is the lateral thyrohyoid ligament?

Posterolateral thickenings of the membrane

What is the anatomical significance of the cuneiform cartilages?

They are located within the aryepiglottic folds and act to strengthen the folds.

Fibro-elastic membrane

Connects the laryngeal cartilages and completes

the architectural framework of the laryngeal

cavity

Cricothyroid ligament

Originates from the

cricoid cartilage and extends superiorly, where

it terminates with a free (unattached) upper

margin - which forms the vocal ligament

(under the vocal fold

Attached anteriorly to the thyroid

cartilage, and posteriorly to the arytenoid

cartilage

➢ Thickened anteriorly in the midline to

form a distinct median cricothyroid

ligament

Fibro-elastic membrane

o Quadrangular membrane

Between the anterolateral

arytenoid cartilage and the

lateral aspect of the epiglottis;

also attached to the

corniculate cartilage

➢ Free upper and lower

margin (thickened to

become the vestibular

ligament - under the

vestibular fold)

Vocal Folds

Two bands of smooth

muscle tissue

o Under the control of the

muscles of phonation, they

are abducted, adducted,

relaxed and tensed to

control the pitch of the

sound created

o Opening between them

(Rima glottis)

What is the vestibular fold also known as?

False vocal cords.

Superior to the true vocal cords

o Consist of the vestibular ligament (free lower

edge of the quadrangular membrane)

covered by a mucous membrane

o Fixed folds - protect the larynx

o Opening between them - Rima vestibuli

Cricothyroid joints

Between the inferior horns of the

thyroid cartilage and the cricoid

cartilage

o Enable the thyroid cartilage to

move forward and rotate

downward on the cricoid

cartilage - lengthens and puts

tension on the vocal ligaments

Crico

-arytenoid

Between articular facets on the

superolateral surfaces of the

cricoid cartilage and the bases of

the arytenoid cartilages

o Enable the arytenoid cartilages to

slide away or toward each other