Spinal Nerves

Question 1

How many pairs of spinal nerves are there?

Answer 1

31 pair

Question 2

How many cervical nerve pairs?

Answer 2

8 pair

Question 3

How many thoracic nerve pairs?

Answer 3

12 pair

Question 4

How many lumbar nerve pairs?

Answer 4

5 pair

Question 5

How many sacral nerve pairs?

Answer 5

5 pair

Question 6

How many coccygeal nerve pairs?

Answer 6

1 pair

Question 7

Where are the cervical nerves found in relationship to the vertebrae?

Answer 7

found ABOVE the vertebrae

Question 8

Where are the rest of the spinal nerves found in relationship to its vertebrae?

Answer 8

found BELOW the vertebrae

Question 9

How are the spinal nerves attached to the cord?

Answer 9

via anterior and posterior roots

Question 10

What are other names for the anterior roots of the spinal nerves?

Answer 10

ventral or motor

Question 11

What are other names for the posterior roots of the spinal nerves?

Answer 11

dorsal or sensory

Question 12

What do the anterior/ventral/motor roots carry?

Answer 12

efferent axons

Question 13

Where are the cell bodies of the efferent axons found?

Answer 13

anterior (ventral) or lateral (if there) horns

Question 14

Where are efferent neurons found?

Answer 14

anterior/ventral/motor roots

Question 15

How are the anterior and posterior roots attached to the cord?

Answer 15

via a series of rootlets

Question 16

What do the posterior/dorsal/sensory roots carry?

Answer 16

afferent axons

Question 17

Where are afferent spinal cell bodies found?

Answer 17

posterior (dorsal) root ganglion (spinal ganglion)

Question 18

Where do the posterior roots attach to the cord?

Answer 18

posterolateral sulcus

Question 19

Where are the spinal ganglia found?

Answer 19

inside or just medial to the intervertebral foramen, beyond the dura mater

Question 20

Where are the C1 and C2 ganglia located?

Answer 20

at their respective vertebral arches

Question 21

Where are the sacral ganglia found?

Answer 21

within the vertebral canal

Question 22

Where are the coccygeal ganglia found?

Answer 22

inside the dura mater

Question 23

T/F: the anterior and posterior roots combine to form a mixed spinal nerve?

Answer 23

True

Question 24

What nerve is given off right after the roots become a mixed spinal nerve?

Answer 24

meningeal (recurrent meningeal/sinuvertebral) branch

Question 25

What is the 1st branch given off of the mixed spinal nerve?

Answer 25

meningeal branch

Question 26

Where is the meningeal branch present?

Answer 26

at all spinal levels

Question 27

Where does the meningeal branch reenter the vertebral canal?

Answer 27

through the IVF

Question 28

What does the meningeal branch divide into in the IVF?

Answer 28

ascending, transverse, and descending branches

Question 29

How are the meningeal branches classified?

Answer 29

somatosensory and sympathetic

Question 30

What do the meningeal branches supply?

Answer 30

dura, blood vessels, periosteum, ligaments and intervertebral discs in anterior and lateral portions of the canal

Question 31

What area of the canal does the meningeal branches supply?

Answer 31

anterior and lateral portions of the canal

Question 32

What does the mixed spinal nerve divide into?

Answer 32

posterior (dorsal) primary rami | anterior (ventral) primary rami

Question 33

What does the posterior/dorsal primary ramus divide into?

Answer 33

lateral and medial branches (except C1)

Question 34

How is the posterior primary ramus compare in size to the anterior primary ramus?

Answer 34

smaller except at C1, S4 and S5 levels

Question 35

What does the posterior/dorsal primary ramus innervate?

Answer 35

MOTOR: to deep back muscles "paraspinal musculature" SENSORY: skin on either side of spine

Question 36

What does the anterior primary rami innervate?

Answer 36

MOTOR: anterior and lateral trunk muscles, skeletal muscles of the extemities SENSORY: skin of the extremities as well as anterior and lateral trunk (proprioception too)

Question 37

What do the anterior primary rami contribute to?

Answer 37

great plexuses (brachial, lumbar, sacral)

Question 38

Where are the sympathetic chain ganglia found?

Answer 38

either at or just medial to the bifurcation of the mixed spinal nerves

Question 39

What does the white ramus communicans carry?

Answer 39

myelinated axons

Question 40

Where are the white ramus communicans cell bodies found?

Answer 40

lateral horn cells at cord levels T1-L2

Question 41

What kind of fibers enter the sympathetic chain?

Answer 41

preganglionic sympatetic fibers

Question 42

What do the preganglionic sympathetic fibers do in to sympathetic chain?

Answer 42

1) synapse at the same level (move up/down chain and synapse) 2) pass right on through and synapse in greater/lesser/least splanchnic nerves

Question 43

What nerves pass right on through the sympathetic chain?

Answer 43

splanchnic nerves

Question 44

What do the gray ramus communicans carry?

Answer 44

unmyelinated postganglionic sympathetic axons

Question 45

Where are the cell bodies of the gray ramus communicans found?

Answer 45

sympathetic chain to the spinal nerve

Question 46

Where is the gray ramus communicans found?

Answer 46

with EVERY spinal nerve

Question 47

What is the C1 posterior rami called?

Answer 47

suboccipital nerve

Question 48

How is the C1 suboccipital nerve classified?

Answer 48

exclusively motor

Question 49

What does the suboccipital nerve supply?

Answer 49

suboccipital muscles: rectus capitis posterior major and minor, obliquus capitis superior and inferior, semispinalis capitis

Question 50

What makes up the suboccipital nerve?

Answer 50

C1 posterior primary ramus

Question 51

Does the posterior primary ramus C1 spilt?

Answer 51

NO

Question 52

Does the suboccipital nerve have a dermatome level?

Answer 52

NO

Question 53

What does the posterior primary rami of C2 split into?

Answer 53

medial and lateral branches

Question 54

What is another name for the C2 medial branch?

Answer 54

greater occipital nerve

Question 55

What sensory information does the greater occipital nerve carry?

Answer 55

posterior neck and scalp

Question 56

What does the lateral branch of C2 carry?

Answer 56

MOTOR: semispinalis capitis, longissimus capitis, splenius capitis muscles

Question 57

What branches does the posterior primary rami of C3 have?

Answer 57

medial and lateral branches

Question 58

What is the medial branch of C3 called

Answer 58

third (least) occipital nerve

Question 59

What does the least (third) occiptial nerve supply?

Answer 59

SENSORY: skin of posterior neck

Question 60

What does the lateral branch of C3 supply?

Answer 60

MOTOR: semispinalis capitis, longissimus capitis, splenius captis muscles

Question 61

What do the C4-C8 posterior primary rami branch into?

Answer 61

medial and lateral branches

Question 62

What do the medial branches of C4-C8 supply?

Answer 62

SENSORY: skin of posterior neck

Question 63

What do the lateral branches of C4-C8 supply?

Answer 63

MOTOR: iliocostalis cervicis, lingissimus cervicis, longissimus capitis