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Flashcards in CN XI Deck (25)
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1

What fibers are carried by the accesssory nerve?

exclusively motor

2

What are the wo roots of CN XI that contribute lower motor neurons?

cranial and spinal

3

What muscles are supplied by CN XI?

SCM, Trapz, and muscles of the soft palate, pharynx and larynx

4

Where are the cell bodies which contribute axons to the cranial root of the accessory nerve?

nucleus ambiguus

5

Where is the spinal nucleus of the accessory nerve found?

anterior horn of the gray matter

6

T/F: the spinal nucleus of the accessory nerve extends from the foramen magnum to the C7 cord level.

False; but it does extend from foramen magnum to the the C5 or C6 cord level

7

Where is the apparent origin of the cranial root CN XI?

MO

8

After the two roots of CN XI combine, where does CN XI exit the skull?

jugular foramen

9

What other cranial nerves share a common skull exit with CN XI?

IX and X

10

After exiting the skull, fibers from which root separate and join the vagus nerve?

fibers of the cranial root

11

Where do fibers from the cranial root of CN XI join the vagus nerve?

at the inferior ganglion

12

Where are the fibers of the accessory nerve, which are carried by the vagus, distributed?

pharyngeal plexus, external and recurrent laryngeal nerves as well as the motor supply of the laryngeal muscles

13

What is the only laryngeal muscle that CN XI does not supply motor info to?

cricoarytenoid (supplied by external laryngeal nerve)

14

What is the apparent origin of the spinal root of CN XI?

lateral aspect of cervical cord between anterior and posterior rootlets

15

Ascending rootlets combine into the spinal root, forming a trunk which will arise between what structures?

denticulate ligaments and posterior rootlets

16

Where does the spinal root of CN XI enter the skull?

foramen magnum (this is efferent info)

17

After the spinal root combines with the cranial root, what does it pass through?

jugular foramen

18

T/F: CN XI pierces teh SCM.

False; CN XI passes deep to SCM

19

T/F: CN XI traverses the posterior triangle and pierces teh trapezius muscle.

False; it traverses the posterior triangle but travels deep to the trapz

20

Considerable evidence suggests that the trapezius receives some motor supply from where (as well as from CN XI)?

from the cervical plexus with CN XI supplying the upper and middle portions and cervical plexus supplying the lower 2/3

21

A lesion of the spinal component of CN XI would lead to paralysis of the SCM on one side. What action would then be impossible?

turning of the face to the unaffected/contralateral side

22

T/F: spasmodic torticollis is relatively pain free.

False; it extremely painful

23

What is the condition described as episodic contraction of the SCM and Trapz?

spasmodic torticollis

24

What kind of info is carried by the C3 and C4 rootlets to the Trapz?

proprioceptive info and maybe motor

25

T/F: paralysis of the trapz leads to brachial plexus traction.

True