Larynx & Pharynx Flashcards
True or false? The thyroid cartilage is closed over posteriorly.
False. It is deficient posteriorly.
What are the two movements of the arytenoid cartilages?
Swivelling & sliding.
How do we produce sound using the vocal ligaments?
We adduct them and push air up through them, causing them to vibrate against each other.
Name the borders of the quadrangular membrane.
Anterior: aryepiglottic ligament
Medial: epiglottis
Posterior: vestibular ligament
Lateral: arytenoid cartilage
What does contraction of the posterior cricoarytenoid muscles do?
It adducts the muscles, which pull the arytenoid processes and abducts the vocal cords.
What does contraction of the lateral cricoarytenoid muscles do?
It abducts the muscles, which pull the arytenoid processes and adducts the vocal cords.
Which muscles are responsible for the swivel movement of the arytenoids?
The posterior & lateral cricothyroid muscles.
Which muscles are responsible for the sliding movement of the arytenoids?
The transverse & oblique arytenoid muscles.
What happens when vocalis & thyroarytenoid contract?
They pull the angle of the thyroid cartilage back toward the arytenoids, causing the vocal ligaments to become more lax and vibrate with a lower frequency, producing a lower pitch sound.
What happens when cricothyroid contracts?
The vocal cords are tightened and produce a higher pitch sound.
Describe which muscles are used to produce higher/lower pitch sounds.
To produce lower pitch sounds, vocalis and thyroarytenoid contract, making the vocal ligaments become more lax and vibrate with a lower frequency.
For high pitch sounds, cricothyroid contracts and the vocal ligaments are tightened.
Which structures does the internal laryngeal nerve supply?
It provides sensory innervation to the mucosa ABOVE the vocal folds.
Which structures does the external laryngeal nerve supply?
The cricothyroid muscle.
What will happen if the external laryngeal nerve is damaged?
You won’t be able to regulate pitch and produce higher sounds.
Which structures does the recurrent laryngeal nerve supply?
The intrinsic muscles (except cricothyroid) and the mucosa BELOW the vocal ligaments.
What will happen if the recurrent laryngeal nerve is damaged on one side?
The vocal ligament on that side will fall into a position halfway between abduction & adduction and won’t be able to move. When you try to push air between them, you’re not going to get good vibration, so you get a hoarse voice and stridor (a sense of effort in speaking).
What are the main vessels supplying the larynx?
The superior thyroid & superior laryngeal vessels.
If you needed to do an emergency airway puncture, would you use a tracheotomy or a cricothyroid membrane puncture? Why?
You only do tracheotomies in clinical settings because of how vascular the area is - you would definitely cut a vessel, letting blood drain into the airways and essentially drowning your patient. In an emergency, you should look for the cricothyroid membrane.
What are the two functions of salpingopharyngeus?
Elevating the pharynx/pulling on the opening of the auditory tube.
What are the two functions of palatopharyngeus?
Elevating the pharynx/depressing the soft palate.
What is the function of stylopharyngeus?
Elevating the pharynx.
From where does the pharynx receive its sensory nerve supply?
The trigeminal nerve (pharyngeal branches of maxillary division), the glossopharyngeal nerve (pharyngeal branches) and the vagus nerve (internal laryngeal nerve).
From where does the pharynx receive its motor nerve supply?
The pharyngeal branches of vagus, except for stylopharyngeus, which is innervated by the glossopharyngeal nerve.
What is the role of the soft palate?
It seals the nasal cavity during swallowing and coughing, and also seals the oral cavity during chewing to allow unimpeded breathing.
