Larynx Flashcards
what is the larynx?
an anatomical valve that allows air to reach the respirator system while directing food and liquids to the digestive system. It also provides phonating mechanism for voice production
At what cervical spine level is the hyoid bone located?
C3
at what cervical spine level is the greater horn of the thyroid cartilage located at?
C4
what cervical spine levels does the thyoid membrane run?
C3-C4
At what cervical spine level is the cricoid thyroid (of the larynx) found at?
C6
what cervial spine levels does the larynx lie parallel to?
c3-c6
is the larynx longer or shorter in females and children?
shorter (higher pitch voice)
how many cartilages make up the larynx? are they paired or unpaired?
3 unpaired, 3 paired = 9 total
what are the three compartments of the larynx?
- Vestibule
- Ventricle
- Infraglottic cavity
where is the vestibule compartment of the larynx located?
superior to vestibular folds (false vocal cords) up to the level of the epiglottis; above the vocal folds
where is the ventricle compartment of the larynx located?
extends laterally between vestibular folds and superior to vocal folds
where is the inraglottic cavity of the larynx located?
extends from the vocal cords to the inferior border of the cricoid cartilage; below the vocal cords
are the vocal ligaments located superior or deep to the vocal folds?
vocal ligaments = deep to vocal folds
what is another name for the false vocal chords?
vestibular folds
which laryngeal cartilages function to produce variations in voice pitch? what is the function of the other laryngeal cartilages then?
thyroid, cricoid, and both of the arytenoid cartilages function in producing pitch variations. the rest of the cartilages function in keeping food and foreign bodies outside of the larynx
on what cartilage is the laryngeal prominence found?
thryoid cartilage (its the adams apple)
what muscles are attached to the lateral side of each laminae on the thyroid cartilage?
inferior constrictror, thryohyoid, and sternoThyroid muscles
Over what joint/with what ligament do the thryoird and cricoid cartilages articulate? what type of movement does this joint allow?
the posterior cricoid is thicker than the anterior part, and it has lateral facets for articulation with the inferior horn of the thryoid cartilage. The criothryoid ligaments help stabilize the joint
The joint allows for the thyroid cartilage to glide and tilt on the cricoid cartilage
what articulates with the anterior area of the cricoid cartilage?
the cricothyroid muscle on the anterolateral surface
what does the superior horn of each thyroid lamina articulate with? how?
the hyoid bone via the thyrohyoid membrane
what cartilage does the arytendoid cartilage articulate with? via what joint?
the cricoid cartilage; via a facet for articulation on the superior surface of the posterior cricoid cartilage
What are the different processes of the arytenoid cartilage? what does each side attach to?
- Muscular process: to intrinsic laryngeal muscles
- Vocal process: to vocal ligaments
- Apex: to aryepiglottic fold
what is the function of the aryepiglottic fold?
helps close the larynx during swallowing
which vocal folds (true or false) are attached to the arytenoid cartilage?
both!
The 3-sided structure of the arytendoid allows for what movements?
- anterior movement (gliding forward) onto cricoid cartilage
- Swiveling to allow vocal processes to move laterally and then the vocal ligament to move under
what is the function of the corniculate and cuneiform cartilages?
stabilize the structural integrity of the aryepiplottic folds when they are closed (located directly on top of arytenoid cartilage)
what is the epiglottis attached to? what’s its function?
attached inferiorly to the thryoepiglottic ligament to the inside of the thyroid cartilage at the laryngeal prominence;
also attached to the hyoid bone via hyoepiglottic ligament;
function: to close the laryngeal inlet during swallowing
where are the vocal ligaments located?
under the vocal folds, extending from the inside of the laryngeal prominence to the vocal processes of the arytenoid cartilages
what is the conus elasticus?
cricothyroid ligamentS (medial + lateral) + vocal ligaments
what is considered the vocal folds?
vocal ligaments + cricothyroid ligaments covered by mucous membrane
How is pitch highered?
When the vocal ligament is stretched (due to the thryoid lamina movin forward) the air passes through can causes the pitch to be higher
what is the rima glottidis?
the space between the vocal folds where air goes throuh
what happens to the rima glottidis wen the the vocal ligaments are abducted? adducted?
abducted ligaments = decrease in space
adducted ligaments = increase in space
what is the glottis?
the larynx at the level of the vocal folds
where are the vestibular (fast vocal cords) folds located?
superior to the vocal folds and extend from thyroid to arytenoid cartilages
the inferior edge of what membrane forms the vestibular folds?
quadrangular membrane (extends from arytenoid to thyroid cartilage)
the superior edge of what membrane forms the aryepiglottic folds?
quadrangular membrane
what do the aryepiglottic folds engulf?
the cuneiform and corniculate cartilages
what is the function of the vestibular folds?
protective mechanism for closing the laynx during swallowing
what is the space between the vestibular folds called? between the vocal folds?
between vestibular folds = rima vestibuli
between vocal folds = rima glottis
where is the arylepiglottic fold located?
top lip of the quadrangular membrane extending between the epiglottis and arytenoid cartilages
where is the vestibular fold located?
bottom lip of quadrangular membrane extending btween thyroid and arytenoid cartilages
what space is surrounded by the quadrangular membrane?
vestibule of the larynx (laryngeal aditus)
what are the muscles of the laryngeal inlet?
transverese arytenoid, oblique arytenoid, thyroepiglottic
what are the muscles of the laryngeal inlet?
transverese arytenoid, oblique arytenoid, thyroepiglottic
where is the transverse arytenoid muscle located?is it a paired or unpaired muscle?
unpaired; located posteriorly extending from one arytenoid cartilage to the other (behind the “X”.. obliques)
where is the thyroepiglottic muscle located? it is a continuation of which muscle?
continuation of thyroartenoid; located behind the aryeopiglottic fold to insert on the epiglottic cartilage.
what nerve innervates the transverse arytenoid muscle?
Recurrent laryngeal (X)
what nerve innervates the thyroepiglottic muscle
Recurrent laryngeal (X)
what is the action of the transverse arytenoid muscle?
- approximate the aryepiglottic folds and moves the arytenoid cartilages toward the epiglottis as it CLOSES
- CLOSE THE LARYNGEAL INLET to keep foreign bodies out of larynx
what nerve innervates the lateral cricoarytenoid ?
recurrent laryngeal (X)
what nerve innervates the posterior cricoarytenoid ?
recurrent laryngeal (X)
what does bilaterlal paralysis of the posterior cricoarytenoid muscle cause?
narrowing of the rima glottidis and leads to suffocation
what muscle is involved in phonation
**cricothyroid (+ some lateral cricoarytenoid +vocalis)
what never innervates the cricothyroid muscle?
external laryngeal (from superior laryngeal of X)
what pierces the thyrohyoid membrane?
the internal laryngeal nerve (off superior laryngeal nerve) + superior thyroid artery
what muscle is innervated by the external laryngeal nerve? what is it’s clinical significance?
the cricothyroid muscle; it is at risk for damage during thryoidectomy or cricoectomy
thryoarytenoid muscle action
pulls arytenoid cartilages naterioly and slackens the vocal ligaments LOWERING VOCAL PITCH
what is the cricothyroid muscle attached to?
NOT THE ARYTENOID CARTILAGE!!! onto anterolateral criothyroid cartilag and inferior horn of thyroid cartilage
what is the thyroarytenoid muscle innervated by?
recurrent laryngeal nerve (X)
what muscle extends from the thryoarytenoid muscle?
- thyroepiglottic muscle
2. vocalis muscle
what muscle attaches to the vocal ligament?
vocalis
what arteries supply the larynx?
superior laryngeal (off superior thyroid.. external carotid) and inferior laryngeal (off of thyrocervical trunk.. subclavian artery)
what is the path of the superior laryngeal artery?
off of superior thyroid artery from external carotid; pierces the thryohyoid membrane and runs with the internal laryngeal nerve (branch of superior laryngeal nerve from vagus)
what is the path of the inferior larygneal artery
from the thyrocervical trunk of the subclavian artery; runs with the recurrent laryngeal nerve (off of vagus nerve)
what is the function of the external laryngeal nerve (motor/sensory)? what is the function of the internal laryngeal nerve?
External laryngeal = motor (to cricothyroid muscle)
Internal laryngeal = sensory to larynx superior to the vocal folds (true vocal chords)
what is the path of the recurrent laryngeal nerve?
branch of vagus;
On the right side of the body, it comes UNDER (deep) to the SUBCLAVIAN artery, on the left side it comes UNDER the AORTIC ARCH;
then it rises superiorly BETWEEN the trachea and esophagus (medial to the thyroid gland) and provides motor to all intrisic laryngeal muscles except cricothyroid and then it continues as a sensory nerve below the vocal cords
what is a laryngeal spasm? how does it occur?
when food goes down the wrong pipe.. due to muous membrane of laryngeal aditus is very sensitive and causes coughing immediately after something touches it. BREATHING and coughing occur
where is a trachostomy/tracheotomy performed?
between the 2nd and 3rd tracheal rings (where the isthmus of the thyroid is located)
why is an incision (for a trachostomy) below the 3rd tracheal ring not advised?
because it will be below the thyroid isthmus and the plexus of inferior thyroid veins are present as well as the thyroid ima artery
where is the oblique arytenoid muscle located? is it a paired or unpaired muscle?
paired; located superficially to the transverse arytenoids (if looking from posterior side); forms “X”, its muscle fibers continue as the arylepiglottic muscle
what nerve innervates the oblique arytenoid muscle
Recurrent laryngeal (X)
what is the action of the oblique arytenoid muscle?
- approximate the aryepiglottic folds and moves the arytenoid cartilages toward the epiglottis as it CLOSES
- CLOSE THE LARYNGEAL INLET to keep foreign bodies out of larynx
what is the action of the thyroepiglottic muscle
- approximate the aryepiglottic folds and moves the arytenoid cartilages toward the epiglottis as it CLOSES
- CLOSE THE LARYNGEAL INLET to keep foreign bodies out of larynx
* ** 3. changes the size of the laryngeal inlet by assisting the approximation of the epiglottis to the aryepiglottic folds
what are the muscles of the vocal folds? what is their main goal/function?
lateral cricoarytenoid muscle, posterior cricoarytenoid muscle, cricothyroid muscle, thyroarytenoid muscle
Overall function: to open and close the Rima Glottidis
what is the function of the Lateral cricoarytenoid muscle?
Adduction = closes the rima glottidis
How? rotates the arytenoids ANTERIORLY so that the vocal process (has vocal ligaments attached) swing medially to close the Rima Glottidis
what is the function of the posterior cricoarytenoid muscle?
Abdution = OPENS the rima glottidis
How? rotates the muscular process of the arytenoids MEDIALLY so that their vocal processes ABDUCT and the rima glottidis is open
what happens when vocalis is contracted?
tiny adjustments to voice and pitch and FUNCTIONS DURING WHISPERING!
what is the function of the reccurent laryngeal nerve? where does it supply?
MOTOR to ALL larynx muscles (intrinsic) EXCEPT cricothyroi;
SENSORY to larynx INFERIOR to the vocal folds
what is a laryngeal obstruction? how does it occur?
blockage of the larynx and thus the flow of air to the trachea. Occurs as a result of an OBJECT LODGED IN THE RIMA GLOTTIDIS. Little noise is made before losing consciousness because the individual cannot get air. Heimlich maneuver is performed
when is the heimlich maneuver performed? how does it work?
if laryngeal obstruction occurs; it increases the intrabdominal pressure in order to dislodge the thing stuck
where is an emergency cricothyrotomy performed?
through the median cricothyroid ligament (between the cricothyroid cartilage and the first tracheal ring), and a tube is place in it to create an airway
what is the difference between a tracheotomy and tracheostomy?
tracheotomy: slit incision in the trachea
tracheostomy: round or square hole
