Throat anatomy (2)

Question 1

What supplies somatic sensation to all the parts of the oral cavity? (palate, tongue, cheeks)

Answer 1

Palate = CNV2 (maxillary)
Cheeks = CNV3 (mandibular)
Anterior 2/3 tongue = CNV3 (mandibular)
Posterior 1/3 tongue = CNIX (glossopharyngeal)

Question 2

What supplies special sensation to the tongue (taste)?

Answer 2

Anterior 2/3 = CNVII (facial - via chorda tympani)

Posterior 1/3 = CNIX (glossopharyngeal)

Question 3

What muscles provide motor to the tongue and what is their innervation?

Answer 3

Extrinsic muscles:

• genioglossus (CNXII)
• hyoglossus (CNXII)
• styloglossus (CNXII)
• palatoglossus (CNX - vagus)

4x intrinsic pairs (CNXII - hypoglossal)

Question 4

What nerve provides motor innervation to the tongue and what is the exception?

Answer 4

All CNXII (hypoglossal)
EXCEPT palatoglossus (CNX - vagus)

Question 5

What are the 3 parts of the pharynx, where are they and what is their sensory innervation?

Answer 5

Nasopharynx: eustachian tube - soft palate
(CNV2 - maxillary)

Oropharynx: soft palate - hyoid
(CNIX - glossopharyngeal)

Laryngopharynx: hyoid - C6
(CNX - vagus - superior laryngeal nerve)

Question 6

What muscles constrict the pharynx and what is their innervation?

Answer 6

Circular: 
superior constrictor (CNX)
middle constrictor (CNX)
inferior constrictor (CNX)

Longitudinal:
palatopharyngeus (CNX)
salpingopharyngeus (CNX)
stylopharyngeus (CNIX - glossopharyngeal)

Question 7

What nerve provides motor innervation to the pharynx and what is the exception?

Answer 7

CNX (vagus)
except stylopharyngeus (CNIX - glossopharyngeal)

Question 8

What are the salivary glands and what is their innervation?

Answer 8

Parotid (opposite 2nd upper molar)
- CNIX (glossopharyngeal)

Sublingual, Submandibular
- CNVII (facial) - via chorda tympani

Question 9

What are the muscles of the soft palate and what is their innervation?

Answer 9

Palatopharyngeus (CNX) - also a longitudinal constrictor
Levator veli palatini (CNX)
Musculus uvulae (CNX)
Palatoglossus (CNX) - extrinsic muscle of tongue

Tensor levator palatini (CNV3 - mandibular)

Question 10

What nerve proves motor innervation to the soft palate and what is the exception?

Answer 10

CNX (vagus)

Tensor veli palatini (CNV3)

Question 11

What are the true and false vocal cords formed of and what is the space between them?

Answer 11

True: arytenothyroid ligament
False: arytenoepiglottis ligament

Gap: rima glottidis

Question 12

Which muscles adduct the vocal cords and what effect does this have? What nerve innervates this?

Answer 12

Decrease volume

Lateral cricoarytenoids
Transverse arytenoids
Oblique arytenoids

Recurrent laryngeal neve (CNX)

Question 13

What muscle abducts the vocal cords and what effect does this have? What nerve provides innervation?

Answer 13

Increase volume

Posterior cricoarytenoids

Recurrent laryngeal nerve (CNX)

Question 14

What muscle tenses the vocal cords and what effect does this have? What nerve provides innervation?

Answer 14

Increase pitch

Cricothyroid

Superior laryngeal nerve (CNX)

Question 15

What muscle relaxes vocal cords and what effect does this have? What nerve proves innervation?

Answer 15

Decrease pitch

Thyroarytenoid

Recurrent laryngeal nerve (CNX)

Question 16

What nerve provides motor innervation to move the vocal cords? What is the exception?

Answer 16

Recurrently laryngeal nerve

Cricothyroid (tensor) = superior laryngeal nerve

Question 17

What are the strap muscles and what is their innervation?

Answer 17

Thyrohyoid,
Sternothyroid
Sternohyoid
Omohyoid

C1-3 (spinal nerves)

Question 18

What test is done to test the hypoglossal nerve and what are the results?

Answer 18

Stick tongue out

Deviates towards injured nerve

Question 19

What test is done for the vagus nerve and what are the results?

Answer 19

Say ‘ahhh’

Deviates away from injured nerve (tests musculus uvulae)