Larynx anatomy Flashcards
What are the cartilages of the larynx?
Epiglottic
Thyroid
Cricoid
Arytenoid
Epiglottic cartilage
Function: protects the laryngeal inlet during swallowing
Thyroid cartilage
Prominence forms the Adam’s apple
Cricoid cartilage
Only cartilage that completely encircles the airway
Arytenoid cartilage
Vocal cords and their muscles attach here. Movement of the this cartilage controls the size of the rima
What are the joints of the larynx?
Cricothyroid joint
Cricoarytenoid joint
Cricothyroid joint
- Allows the thyroid cartilage to rotate and tip forward.
- Stretches the vocal cords to create a higher pitch
Cricoarythenoid joint
Allows aretynoids to slide laterally and widens space
- pulls apart vocal cords
What nerve provides sensory innervation to the infraglottic compartment?
Recurrent laryngeal nerve
Quadrangular membrane
- inferior border is the vestibular ligament which forms the false vocal cords
Cricovocal membrane
- aka conus elasticus
- upper free border is the vocal ligament which helps to form the true vocal cords
Which artery supplies the infraglottic compartment?
Inferior laryngeal artery
What nerve provides innervation to the supraglottic apartment?
Internal laryngeal nerve provides sensory innervation
What nerve provides motor innervation to the infraglottic apartment?
Recurrent laryngeal nerve
- Exception: cricothyroid muscle is innervated by the external laryngeal nerve
Which artery supplies the infraglottic compartment?
Inferior laryngeal artery and superior laryngeal artery anastomose here
What is the rima glottidis?
The slit between the vocal cords. Its size is manipulated during phonation and breathing
Is the rima glottidis open or closed during breathing?
Open
Is the rima glottidis open or closed during forced respiration?
Open wide
Is the rima glottidis open or closed during phonation?
It is closed so that air can be passed over the stretched vocal cords.
Is the rima glottidis open or closed during phonation?
It is closed so that air can be passed over the stretched vocal cords.
Cricothyroid membrane
- where cricothyrotomy (tracheotomy) is peformed to open the airway in an emergency
What does abducting the vocal cords to to the rima?
It opens the rima
What does adducting the vocal cords do?
It closes the rima
What muscles abduct the rima?
Only the posterior cricoarytenoid muscles
What muscles close the rima?
- transverse arythenoid
- lateral cricoarythenoid
What is the function of the cricothyroid muscles?
They slide the thyroid anteriorly and tense the vocal cords to raise the pitch of the voice.
Clinical correlate: What happens if there is unilateral damage to the external laryngeal nerve?
Loss of ability to make high pitched sounds
Clinical correlate: What happens if there is unilateral damage to the recurrent laryngeal nerve?
- The affected vocal cord becomes paralyzed and does not move during phonation or respiration.
- hoarseness of voice and risk of aspiration pneumonia
What makes up the true vocal cords?
The upper free border of the conus elasticus plus its mucus membrane.
- the vocal cord is also called the vocal fold (ligament + mucous membrane)
What makes up the false vocal cords?
- the inferior border of the quadrangular membrane plus its mucous membrane
- the false vocal cords are also called the vestibular fold (ligament + mucous membrane)
