The larynx Flashcards
What is the larynx made up off?
Composed of 9 cartilages connected by membranes, ligaments and associated muscles
It contains the vocal folds
What are the 2 roles of the larynx?
- Allows human beings to articulate sound and the vocal folds play a key role in phonation
- The larynx also protects the airway
Where is the larynx located?
Located in the anterior neck
Suspended from the thyrohyoid membrane
What 2 structure is the larynx suspended by and is that structure a part of the larynx?
Thyrohyoid membrane
It is not part of the larynx
The larynx is anterior to the L__________ and the o____________
Laryngopharynx and Oesophagus
Which part of the pharynx does the laryngeal inlet open into?
The laryngopharynx part
Where does the laryngeal cavity extend from and too?
From the laryngeal inlet to the cricoid cartilage
What is the Cartilaginous skeleton lined with?
Mucosa
What lies in the superior portion of the larynx?
The laryngeal inlet (which is continuous with the laryngopharynx)
What lies in the middle portion of the larynx?
The vestibular folds (“false vocal cords”)
The vocal folds (“true vocal cords”)
The vestibular folds are described as what type of vocal cords and why?
They are the “false vocal cords” because they do not vibrate when air passes through them
Which folds have a role in sound production?
The vocal folds NOT the vestibular folds
What are the 3 unpaired cartilages called?
- Epiglottis
- thyroid cartilage
- Cricoid cartilage
Describe the epiglottic cartilage
Flap of tissue that sits beneath the tongue at the back of the throat.
Leaf-like, unpaired Articulates with thyroid cartilage by elastic ligament
What articulates the thyroid cartilage with epiglottis?
The elastic ligament
What is the function of the epiglottis?
It gets pulled down to close the opening to the airway when food is passing down to the oesophagus (closes the laryngeal inlet)
Epiglottis is the flap that closes the entrance between the pharynx and the trachea when swallowing
What is the name of the point where the 2 lamina that make up the thyroid cartilage meet called?
the laryngeal prominence
What creates the Adams apple?
the laryngeal prominence
Which part of the thyroid cartilage articulates with the cricoid cartilage?
The inferior horn of the thyroid cartilage
Why do men have a larger Adams apple?
Beucaee during puberty hormones make the thyroid cartilage grow bigger in males
Do women have an Adams apple?
Yes but its not as prominent as male
Describe the cricoid cartilage
It is an unpaired cartilage and it is ring shaped
Describe the shape of the cricoid cartilage
It is ring shaped
Anteriorly it has an arch
Posteriorly it ha a lamina
It also has facets to be able to articulate with other cartilages
How does the cricoid bone articulate with other cartilages?
By the means of facets
What is the structure where the cricoid cartilage articulates with the aritonoid cartilage called?
The Cricoarytenoid joint
What is the structure where the cricoid cartilage articulates with the thyroid cartilage called?
Cricothyroid joint
Is the cricoid cartilage above or below the thyroid cartilage?
The cricoid is below the thyroid cartilage
Which carriage is completely closed and resembles a ring shape?
The cricoid cartilage
What is the only paired cartilage we need to know called?
The arytenoid cartilage
Describe the arytenoid cartilage
It is paired
Pyramid shaped
It has 3 processes
What are the 3 processes of the arytenoid cartilage called?
The superior process
The vocal process
The muscular process
Why is the vocal process important?
Important for connecting with the vocal cords
Why is the muscular process important?
Important for connecting with muscles
Where does the arytenoid cartilage sit?
On top of the cricoid cartilage forming the Cricoarytenoid joint
What happens at the Cricoarytenoid joint?
Pivoting of the arytenoid cartilage allowing for movement and tensing of the vocal cords to allow for variations in the sounds we make
What is the roles of the arytenoid cartilage
Opening and closing the vocal cords
What are vocal cords?
They are ligaments covered in mucosa that are attached to the cartilages
How do vocal cords produce sound?
They vibrate when air passes through them
What do you call vocal folds without mucosa?
Vocal ligaments
What is important about the Cricothyroid membrane?
It provides an access if there’s an emergency where a patient may have a block in their airways above the vocal cords
The ducts can make an incision in this membrane to allow airflow
What is the Cricothyroid membrane?
A membrane that extends from the cricoid to the thyroid cartilage
It is thicker superiorly
What are the vocal folds attached to and how?
They attached to the anterior aspect of the thyroid cartilage
Attaches posteriorly to the arytenoid cartilage
What happen when the thyroid and arytenoid cartilage abduct?
They open the vocal cord and allow air to pass through
What happen when the thyroid and arytenoid cartilage adduct?
They close the vocal cord
This creates a very narrow passage for air to pass through
This causes the vocal cords to vibrate and produce sound
What are the 2 muscles responsible for changing the length of the vocal folds called?
- Cricothyroid Muscle
2. Thyroarytenoid Muscle
Where does the Cricothyroid Muscle attach and extend to?
Attaches from the cricoid and extends to the thyroid muscle
What happens when the Cricothyroid muscle contracts?
It tenses the vocal cords stretching them
Where does the Thyroarytenoid muscle attach and extend to?
Attaches from the thyroid cartilage and extends to the arytenoid cartilage
What happens when the Thyroarytenoid muscle contracts?
Shortens and relaxes the vocal cords
Movement of what muscles allows us to create high pitched notes when speaking and how?
Contraction of the Cricothyroid muscle tenses the vocal cords stretching them
This allows the vocal cords to vibrate faster
What is the nerve supply for the Cricothyroid muscle?
It is supplied by the external laryngeal nerve
What is the nerve supply for the Thyroarytenoid muscle?
It is supplied by the recurrent laryngeal nerve
What does adduction mean?
Closing
Which muscles are in charge of closing the vocal fold?
- Interarytenoid Muscles
2. Lateral cricoarytenoid Muscle
Where does the Interarytenoid Muscles attach and extends to?
They are attached from one arytenoid cartilage to another
What do the Interarytenoid Muscles do?
They bring the arytenoid cartilages closer together ultimately pulling the vocal cords closer together adducting the,
What is the nerve supply for the Interarytenoid muscle?
It is supplied by the recurrent laryngeal nerve
Where does the Lateral cricoarytenoid Muscles attach and extends to?
Attaches from the lateral aspect of the cricoid cartilage and extends to the arytenoid cartilage
What happens when the Lateral cricoarytenoid muscle contracts?
It adducts the vocal cords
What is the nerve supply for the Lateral cricoarytenoid muscle?
It is supplied by the recurrent laryngeal nerve
Which muscle is in charge of abduction of the vocal folds?
The Posterior Cricoarytenoid Arytenoid Muscle
Where does the Posterior Cricoarytenoid Arytenoid Muscle attach and extends to?
It begins from the cricoid cartilage and extends to attach to the arytenoid cartilage
What happens when the posterior Cricoarytenoid Arytenoid muscle contracts?
It moves the cricoid cartilage
arytenoid cartilages apart and in the process abducts the vocal folds
What does abduction of the vocal cords mean?
Moving the vocal cords apart (opening them)
What is the nerve supply for the Cricoarytenoid Arytenoid muscle?
It is supplied by the recurrent laryngeal nerve
What is cranial nerve X called?
The vagus nerve
What does the vagus nerve branch into?
The external laryngeal nerve
Which muscle is suppled by the external laryngeal nerve?
The cricothyroid muscle
When does the vagus nerve become the LEFT recurrent laryngeal nerve?
When it moves down and loops around the aorta then moves up superiorly again to become the recurrent laryngeal nerve
When does the vagus nerve become the RIGHT recurrent laryngeal nerve?
When it moves down and loops around the Brachiocephalic trunk then moves up superiorly again to become the recurrent laryngeal nerve
Which muscles are supplied by the recurrent laryngeal nerves
- Thyroarytenoid Muscle
- Interarytenoid Muscles
- Lateral cricoarytenoid Muscle
- Posterior Cricoarytenoid Arytenoid Muscle
When is the recurrent laryngeal nerve at risk?
When you perform any surgeries on the thyroid gland
This is because the thyroid gland is very close t the recurrent laryngeal nerve
Which artery does the recurrent laryngeal nerve have a close relationship with?
The Inferior thyroid artery which supplies the thyroid gland
What happens if the recurrent laryngeal Is severed during surgery?
Loss of speech and sound production as the recurrent laryngeal nerve supplies most of the muscles in the larynx
What is another name for the laryngeal prominence ?
Adams apple
What are vocal cords covered in?
Mucosa
How do the vocal folds open?
when the thyroid and arytenoid cartilage abduct
How do the vocal folds close and what does this do?
When the thyroid and arytenoid cartilage adduct
This creates a very narrow passage for air to pass through
This causes the vocal cords to vibrate and produce sound
Movement of what muscles allows us to create low pitched notes when speaking and how?
Contraction of the Thyroarytenoidmuscle tenses the vocal cords relaxing them
This means the vocal cords vibrate less
Which muscle is the exception to all the others in the larynx and why?
The Cricothyroid muscle as it has a different nerve supply to all the other muscles It is supplied by the external laryngeal nerve
What is the difference between the left and right recurrent laryngeal nerves?
The right recurrent laryngeal nerve loop around the Brachiocephalic trunk
The right recurrent laryngeal nerve loop around the aorta
What are the 5 muscles in the larynx involved in speech production?
- Thyroarytenoid Muscle
- Interarytenoid Muscles
- Lateral cricoarytenoid Muscle
- Posterior Cricoarytenoid Muscle
- Cricothyroid muscle
