1.31 Larynx

Question 1

Name all of the extrinsic/strap muscles of the larynx…

Answer 1

Stylohyoid, digastric, omohyoid, thyrohyoid, sternohyoid,

Question 2

Which muscles are suprahyoid muscles and what is there function?

Answer 2

Stylohyoid, digastric
Elevate hyoid and larynx
*digastric could also depress mandible

Question 3

Which muscles are infrahyoid muscles and what is there function?

Answer 3

Omohyoid, sternohyoid and thyrohyoid
Depress hyoid and larynx
*thyrohyoid elevates larynx

Question 4

What is the function of the sternothyroid muscle?

Answer 4

Depress thyroid cartilage - doest attach to hyoid bone

Question 5

What are the laryngeal cartilages made up of?

Answer 5

All made from hyaline, except for the epiglottis which is elastic

Question 6

What happens during puberty to the vocal ligament?

Answer 6

Thyroid gland and vocal ligament increase due to testorsterone

Question 7

What enables the thyroid to rock backward and forwards?

Answer 7

Synovial joint

Question 8

Which membrane is an emergency tracheostomy performed through?

Answer 8

Cricothyroid membrane

Question 9

Swelling of which cavity causes the vocal folds to close off?

Answer 9

Supraglottic cavity - close of vocal cords

Question 10

Where can fishbones get stuck?

Answer 10

Piriform fossa - can damage nerve to the intrinsic laryngeal muscles

Question 11

What happens to the vocal cords during forced inspiration?

Answer 11

Vocal folds abducted, and rima glottis wide open - vestibule open

Question 12

What happens to the vocal cords during Phonation?

Answer 12

Vocal fold adducted, and vestibule open

Question 13

What happens to the vocal cords during effort closure?

Answer 13

vocal folds and vestibular folds adducted - everything closed

Question 14

What adducts and abducts the vocal ligaments?

Answer 14

Movements of the arytenoid cartilage

Question 15

What is the function and innervation of the Posterior cricoarytenoid?

Answer 15

Innervation - recurrent laryngeal X

Function - rotates and pulls arytenoids down - abducts vocal folds and open glottis (only muscle that does this)

Question 16

What is the function and innervation of the inter-arytenoids?

Answer 16

Innervation - recurrent laryngeal X

Function - adductor of vocal ligament - glottis narrowed - quiet inspiration

Question 17

What happens if paralysis of the posterior cricoarytenoid occurs?

Answer 17

Paralysis of glottis - flaccid closure of glottis - suffocation

Question 18

What is the function and innervation of the lateral cricoarytenoid?

Answer 18

innervation - recurrent laryngeal X 
function - rotates aretynoids - vocal processes brought closer together - glottis narrowed

Question 19

What is the function and innervation of the Thyroarytenoids & vocalis?

Answer 19

Both recurrent laryngeal innervation
Thyroarytenoids - shortening and thickening of vocal cords - changes pitch
Vocalis - attaches to the vocal ligament - fine adjustment

Question 20

What is the function and innervation of the cricothyroid muscle?

Answer 20

Innervation - external laryngeal

Function - elongation of vocal cords - increased pitch

Question 21

Which muscles are involved in the closing of the epiglottis?

Answer 21

Pull epiglottis down - interarytenoids, aryepiglottic

Elevate larynx - digastric, mylohyoid, stylohyoid, genioglossu

Question 22

Which laryngeal muscle isn’t innervated by the recurrent laryngeal nerve?

Answer 22

Cricothyroid

Question 23

What type of innervation does the recurrent laryngeal nerve provide?

Answer 23

Motor - all intrinsic muscles except for cricothyroid

Sensory - BELOW vocal cords

Question 24

What type of innervation does the superior laryngeal nerves (X) provide?

Answer 24

Internal laryngeal - sensory - ABOVE vocal cords

External laryngeal - motor - cricothyroid

Question 25

What is the blood supply to the larynx?

Answer 25

Superior and inferior thyroid artery
Sup. and mid. thyroid vein - int. jugular
Inf. thyroid vein - brachiocephalic

Question 26

Explain some laryngeal dysfunctions by nerve damage?

Answer 26

Causes - trauma, tumours, viral infections
Symptoms - voice, airway, swallowing
lung - can affect it too