Larynx Flashcards
3 functions of the larynx
respiratory, protective, phonation
lateral rotation of what joint widens the rima glottidis
cricoarytenoid
what muscles attach to the cricoarytenoid joints
posterior cricoarytenoids
how is the protective function of the larynx carried out
glottis closure and the cough reflex
how does phonation occur
inspiration increases subglottal pressure, vocal cords vibrate as air passes, the upper respiratory tract modifies vibrations
what dictates the pitch of speech
tension/length of vocal cords, degree of opening and shape of rima glottidis
what nerve innervates the intrinsic muscles of the larynx
inferior laryngeal branch of CN X
what is the laryngeal suspended from and by what
the hyoid bone by fibrous membranes
what type of cartilage is the laryngeal skeleton composed of
mainly hyaline
epiglottis is elastic
what type of mucosa lines the internal larynx
respiratory
what are the 3 regions of internal larynx
laryngeal vestibule, laryngeal ventricles and infra-glottic region
what is collectively known as the supra-glottic region
vestibule and ventricles
what happens to the rima glottidis when the posterior cricoarytenoid muscles contract
opens - forced respiration
what happens to the rima glottidis when the arytenoid muscles contract
closed for phonation
what happens to the rima glottidis when the lateral crico-arytenoid muscles contract
glottis closure with slight opening for whispering
what is the function of the lateral cricoarytenoids
adduct the vocal ligaments via the cricoarytenoid joints
what two structures do the lateral cricoarytenoids attach
muscular process of the arytenoid to the anterior cricoid cartilage.
what does the arytenoid muscle do
abduct the vocal cord via the cricoarytenoid joint
what do the arytenoid muscles attach
the posterior cricoid cartilage to the muscular process of the arytenoid
function of thyroarytenoids
relax vocal ligament to decrease pitch
what do the thyroarytenoids attach
posterior thyroid to the anterior arytenoid cartilage
function of cricoarytenoids
tense the vocal ligament to increase pitch
nod’ the thyroid cartilage
what do the cricoarytenoids attach
anterolateral cricoid cartilage to the inferior horn of the thyroid
describe oral articulation
soft palate tenses and elevates closing the nasopharynx
tongue, teeth and lips modify
describe nasal articulation
soft palate depresses to close the oropharynx, air in the nasal cavities produce ‘m’, ‘n’ or ‘ing’ depending on the teeth and lips
course of superior laryngeal nerve
branches and splits (internal and external)
internal passes through thyrohyoid membrane towards supraglottal mucosa - sensory
external supplies cricothyroid
where does the recurrent laryngeal nerve run in relation to the thyroid
posterior
what does the recurrent laryngeal nerve innervate
all intrinsic laryngeal muscles (except cricothyroid) and sub-glottal folds
when is the recurrent laryngeal nerve referred to as the inferior laryngeal nerve
when it passes behind the cricothyroid joint
what nerve picks up sensation in the cough reflex
Internal branch of the superior laryngeal nerve
describe the cough reflex
superior laryngeal nerve picks up supraglottic object and conveys this to the medulla oblongata
the lateral cricoarytenoid and arytenoid muscles close rima glottidis
inspiratory muscles contract and a jet of air is passed out dislodging the object
where do supraglottic tumours drain
deep cervical lymph nodes
where do glottic tumours present
vocal cords
where do supraglottic spread
paratracheal nodes
where is the tip of the laryngoscope blade placed
vallecula
what is the vallecula
mucosal lined space located between the base of the tongue and anterior epiglottis
how is the hyoid held in place
series of fibrous and muscular connections
function of the hyoid
muscular attachment and airway patency
what does hyoid movement facilitate
swallowing and speech
suprahyoid muscles
digastric (anterior and posterior bellies), mylohyoid, geniohyoid
infrahyoid muscles
thyrohyoid, sternohyoid, omohyoid,
