Larynx Flashcards
what is the main function of the larynx
act as a protective sphincter by stopping food entering the respiratory tract
what 3 single cartilages are found in the larynx
thyroid cartilage
circoid cartilage
epiglottis
what pair of cartilages articulate with the circoid cartilage
arytenoid cartilages
what does movement at the articulation between the arytenoid and circoid cartilage allow
movement of the vocal cords
what is the quadrangular membrane
ligament connecting the epiglottis to the arytenoid cartilage
what are the aryepiglottic folds
the mucus membrane lined quadrangular membrane - this forms the boundary of the laryngeal inlet
what epithelia covers the larynx
pseudo stratified columnar epithelia
what epithelia covers the vocal cords
stratified squamous
what is the name of the false vocal cords
vestibular ligament
what is the vestibular ligament
thickening of the lower border of the quadrangular ligament
what makes up the vocal ligament
thickening of the upper border of the circothyroid ligament
what is the space between the vocal ligament and vestibular ligament called and what does it contain
the laryngeal ventricle contains mucus glands to keep the vocal cords moist
what 2 methods can be used to see the larynx
laryngoscope and a nasoendoscopy
what muscle acts to open/abduct the vocal cords
cricoarytenoid
what nerve supplies the intrinsic laryngeal muscle
recurrent laryngeal
which intrinsic laryngeal muscle is not supplied by the recurrent laryngeal nerve and what is it supplied by
the cricothyroid muscle is supplied by the external branch of the laryngeal nerve
what do the intrinsic muscles of the larynx do
causes movement of the arytenoid/cricoid joint to allow movement of the vocal cords
what happens to the vocal cords when speaking
they are adducted
what happens to the vocal cords when coughing
they are initially adducted but the rise in intra-thoracic pressure causes them to suddenly abduct to expel a force of air
what happens to the vocal cords when breathing
they remain abducted
describe the root of the recurrent laryngeal nerves
L loops under arch of aorta
R loops under subclavian
both ascend up the trachea-oesophageal groove
what is the motor and sensory innervations of the recurrent laryngeal nerve
sensory = infra-epiglottis motor = all intrinsic laryngeal muscles except cricothyroid
what is the motor and sensory innervation of the external branch of the superior laryngeal nerve
motor = cricothyroid sensory = supra-epiglottis
what does a lesion of the external branch of the superior laryngeal nerve cause
hoarse voice when in a higher pitch
what does the cricothyroid muscle do
stretched and tightens the vocal cords to allow higher pitches
what does a unilateral lesion of the recurrent laryngeal nerve result in
hoarse voice and ineffective cough
what does bilateral lesion of the recurrent laryngeal nerve result in
paralysis of both vocal cords giving a severe airway obstruction
what is laryngitis
inflammation of the larynx
what is epiglottitis
inflammation of the epiglottis
what is croup
a viral infection leading to swelling/inflammation
what nerve roots make up the cervical plexus
C1-4
what is the ansa cervicalis
where the nerve roots C1-3 join and loop to form the nerve supply to the infra-hyoid muscles
what structure do the infra-hyoid muscles overly
the thyroid gland
what nerve roots does the phrenic nerve have
C3-5
what is the motor innervation of the phrenic nerve
diaphragm
what dermatomes does the cervical plexus supply sensory innervation
C2-4
what areas are supplied sensory innervation by the cervical plexus
external ear
anterior neck
posteriosuperior scalp
suprascapular fossa