the larynx Flashcards
where does the larynx lie
underneath the strap muscles of the neck
where does the majority of the thyroid gland sit?
inferior to the larynx
what is the function of the larynx?
it is involved in phonation and so speech
how do the hyaline cartilages of the larynx articulate w/ each other?
via small plane synovial joins
what is the largest cartilage of the larynx?
the thyroid cartilage
what forms the laryngeal prominence (Adams apple) ?
the thyroid cartilage
how is the thyroid cartilage attached to the hyoid bone?
via the thryohyoid membrane
what does the thyroid cartilage articulate w/ inferiorly?
the cricoid cartilage
what does the cricoid cartilage articulate w/?
the thyroid cartilage superiorly
the arytenoid cartilages inferiorly
where does the trachea sit in relation to the cricoid cartilage?
the trachea sits inferior to the cricoid cartilage
how is the trachea attached to the cricoid cartilage?
by the cricotracheal ligament
what do the arytenoid cartilages articulate w/?
the cricoid cartilage
how do the arytenoid cartilages move the vocal folds?
they swivel on the surface of the cricoid to move the vocal folds
how many arytenoid carriages are there?
2
which muscles act to move the vocal folds and where do they attach?
the posterior and lateral cricothryoid muscles act to move the vocal folds
they attach on the muscular processes of the arytenoid cartilages
what are the vocal processes of the arytenoid carriages for?
attachment of the vocal folds
what are the cornicualte and cuneiform cartilages?
tiny pieces of cartilage that attach to and support he ayrepiglottic folds between the arytenoid cartilages and the epiglottis
where does the epiglottis lie?
over the opening of the larynx
how does the epiglottis communicate w/ the larynx?
via the aryepiglottic folds
what is the epiglottis formed of?
elastic cartilage
how does the epiglottis bend over the larynx?
passively - there are no muscles that move the epiglottis
what is the function of the epiglottis?
protect the opening of the airway but does not completely seal the top of the larynx during swallowing
where does the quadrangular ligament of the larynx pass between?
between the arytenoid cartilages and the epiglottis
what is the false / vestibular vocal cord?
the quadrangular ligament folds over itself to form a thickened free edge
what is the true vocal cord formed from?
a membrane passing between the cricoid, thyroid and arytenoid cartilages and the upper border of this membrane folds to form a thickened edge called the vocal ligament - this is the vocal cord
what forms the false vocal cord?
the lower free edge of the quadrangular ligament
what forms the aryepiglottic fold?
the upper border of the quadrangular ligament
what is the function of the false / vestibular vocal cord?
protect the true vocal cord beneath it
what is the rims glottidis?
the most posterior space between the vocal cords
where do the true and false vocal cords lie in relation to each other?
the false vocal cord is mot superior and the true vocal cord is inferior
what are the 2 types of muscles of the larynx?
extrinsic
intrinsic
what is the function of the extrinsic muscles of the larynx?
move the entire larynx as a unit
what is the function of the intrinsic muscles of the larynx?
move small components of the larynx
what are the muscles of the larynx?
oblique arytenoid
cricothryoid
thyroarytenoid
lateral cricoarytenoid
posterior cricoarytenoid
transverse arytenoid
what nerve innervates all of the muscles of the larynx except for cricothryoid?
recurrent laryngeal nerve
what nerve innervates cricothryoid?
external laryngeal nerve
what is the function of oblique arytenoid?
pulls the arytenoid cartilages closer together narrowing the gap between the folds
what is the function of cricothryoid?
tense and elongate the vocal ligaments
what is the function of thryoarytenoid?
relax and shorten the vocal ligaments
what is the function of lateral cricoarytenoid?
adduct vocal fold
what is the function of posterior cricoarytenoid?
abduct vocal fold
what is the function of transverse arytenoid?
close rima glottis
where does the recurrent laryngeal nerve arise from?
the vagus nerve
explain the course of the recurrent laryngeal nerve
it arises from the vagus nerve in the thorax and wraps around either the subclavian artery on the right or the arch of the aorta on the left and then ascends the neck between the trachea and the oesophagus before passing under the inferior constrictor of the pharynx to reach the larynx
where do the arteries that supply the larynx arise from?
from the thyroid arteries
where does the superior thyroid artery arise from?
from the external carotid
where does the inferior thyroid artery arise from?
from the subclavian
explain the venous drainage of the larynx
veins drain into the superior and inferior thryoid veins
where do the superior thyroid veins drain into?
the internal jugular veins on either side
where do the inferior thyroid veins drain into?
both drain into the left brachiocephalic vein
explain the lymphatic drainage of the larynx
lymphatic drainage of the larynx is to local paratracheal nodes and to the deep cervical nodes