ANATOMY OF PHONATION PT 1 -Cartilages

Be able to explain the biological functions of the larynx  For each of the cartilages (and the hyoid bone) of the larynx, be able to:  Identify it on a diagram  Describe its structure (including the type of cartilage, landmarks, and how it is positioned and attached relative to the other cartilages)  Describe its function(s) and/or purpose(s), and movement (if it moves)  Describe how all of the laryngeal cartilages (and the hyoid bone) work together for phonation (adduction, abduction, and pitch changes)

What are the biological functions of the larynx?

P,P,B,L,C,D

Airway protection, phonation, breath holding, lifting/stabilizing the trunk, childbirth, and defecation

How does the larynx help with lifting?

It helps with lifting and stabilizing the trunk.

How does the larynx protect the airway?

It seals the airway when foreign objects enter, usually food or liquid

What is the larynx’s “last safety valve”?

It helps prevent foreign matter from entering the airway.

What is penetration?

Material enters the airway but does not go below the vocal folds.

What is aspiration?

Material enters the airway and goes below the vocal folds.

There are _____ unpaired cartilages AND _____ paired cartilages in the _______

3; 3; Larynx

3 unpaired cartilages ARE:

• Cricoid

• Thyroid

• Epiglottis

3 paired cartilages ARE

• Arytenoid

• Corniculate

• Cuneiform

Hyaline =

firm/supportive

Elastic =

flexible/bendy

3 unpaired cartilages: hyaline vs elastic

• Cricoid –

• Thyroid –

• Epiglottis –

• hyaline

• hyaline

• elastic

3 paired cartilages: hyaline vs elastic

• Arytenoid –

• Corniculate –

• Cuneiform –

• hyaline

• elastic

• elastic

Larynx: 1 bone

Hyoid bone

1

Hyoid bone

2

Corniculate

3

Thyroid

4

Arytenoid

5

Cricoid

6

Epiglottis

What type of cartilage is the cricoid cartilage?

Hyaline

Is the cricoid cartilage paired or unpaired?

Unpaired

What is the shape/structure of the cricoid cartilage?

Complete ring; looks like a signet ring

Where is the cricoid cartilage located?

At the top of the trachea

What is the position of the cricoid cartilage compared to the thyroid cartilage?

Just below the inferior thyroid notch

How does the cricoid cartilage differ from front to back?

Thicker/higher in the back and thinner/narrower in front

What cartilage does the cricoid articulate with?

Thyroid cartilage

What joint connects the cricoid and thyroid cartilages?

Cricothyroid joint

What are the primary movements of the cricothyroid joint?

Rocking (rotating) and gliding (secondary)

Which cricothyroid joint movement is primary?

Rocking

What is the secondary cricothyroid joint movement?

Gliding

What type of cartilage is the thyroid cartilage?

Hyaline

Is the thyroid cartilage paired or unpaired?

Unpaired

What is the thyroid cartilage's main structural characteristic?

Largest laryngeal cartilage

What are the important landmarks of the thyroid cartilage?

the cricothyroid notch

What cartilage does the thyroid cartilage articulate with?

Cricoid cartilage

How does the thyroid cartilage articulate with the cricoid?

Via paired processes

What movements does the thyroid cartilage make with the cricoid?

Rocks forward and backward and glides

What joint allows the thyroid and cricoid cartilages to move together?

Cricothyroid joint

What is the relationship between cricothyroid movement and pitch

The movement can be observed during a pitch glide

What type of cartilage is the epiglottis?

Elastic

Is the epiglottis paired or unpaired?

Unpaired

What is the shape of the epiglottis?

Leaflike

What is the main function of the epiglottis?

Folds to protect the airway during swallowing

What is the small stem at the base of the epiglottis?

where the thyroepiglottic ligament attaches

What type of cartilage are the arytenoids?

Hyaline

Are the arytenoids paired or unpaired?

Paired

What shape are the arytenoid cartilages?

Tetrahedron, not pyramid

Where do the arytenoids sit?

On the high-backed posterior and superior (curved & angled) facet of the cricoid

What allows the arytenoids to have a wide range of movement?

Their articulation with the cricoid cartilage

What are the three movements of the arytenoids?

Rock, glide/slide, and rotate

What attaches to the posterior part of the arytenoids?

Vocal folds

What is the function of the muscular process of the arytenoid?

Attachment for abductor/adductor muscles

What is the function of the vocal process of the arytenoid?

Attachment for vocal fold muscles

What does rocking of the arytenoids allow the vocal folds to do?

Adduct/abduct and slightly shorten/lengthen

What does anterolateral gliding of the arytenoids affect?

Vocal fold length

How much rotation occurs around the arytenoid's vertical axis?

Very little

What cartilages are connected by the cricoarytenoid joint?

Cricoid and arytenoid

What are the movements of the cricoarytenoid joint?

Rocking, gliding, and rotating

Which cricoarytenoid joint movement is primary?

Rocking

If rotation occurs at the cricoarytenoid joint, how much occurs?

Minimal

What type of cartilage are the cuneiforms?

Elastic

Are the cuneiforms paired or unpaired?

Paired

Where are the cuneiform cartilages located?

Within the aryepiglottic folds

What is the function of the cuneiform cartilages?

Provide support for the aryepiglottic folds

What is a key landmark/location to remember for the cuneiforms?

Aryepiglottic folds

What type of cartilage are the corniculate cartilages?

Elastic

Are the corniculate cartilages paired or unpaired?

Paired

Where are the corniculate cartilages located?

On the superior surface of each arytenoid

What are the corniculate cartilages a landmark for?

The aryepiglottic folds

Cricoid and thyroid cartilages are attached via the ____, ______, and posterior ______ligaments

anterior, lateral, ceratocricoid

Cricoid and arytenoid cartilages are attached via the ___________and posterior ____________ ligaments

anterior, cricoarytenoid

Is the hyoid a cartilage or a bone?

Bone

Is the hyoid paired or unpaired?

It is one bone, not a paired cartilage

What is the main structural role of the hyoid?

Union between the tongue and laryngeal structures

What is another important function of the hyoid?

Anchor point for the extrinsic laryngeal muscles

What does the hyoid loosely articulate with?

The superior cornu of the thyroid cartilage

What are the parts of the hyoid bone listed in lecture?

Greater and lesser cornu/horns and body

What are the three main parts of the hyoid?

Greater cornu, lesser cornu, and body

How the Cartilages Work Together for Phonation

Arytenoids

• Rock to help the vocal folds adduct and abduct.

• Their muscular processes provide attachment for the muscles that control abduction/adduction.

How the Cartilages Work Together for Phonation

Cricoid + Thyroid

• The cricoid and thyroid form the cricothyroid joint.

• The primary movement is rocking.

• The secondary movement is gliding.

• This joint is involved in changing vocal fold length and tension through the cricothyroid (CT) muscle.

How the Cartilages Work Together for Phonation

Thyroid Movement

• The thyroid cartilage can rock forward and backward.

• It can also glide.

How the Cartilages Work Together for Phonation

Pitch

• The CT muscle rocks the thyroid downward.

• This lengthens and tenses the vocal folds.

• Lengthened and tensed vocal folds raise pitch