Anatomy of Spinal Cord

Question 1

How many segments in spinal cord?

Answer 1

31 segments with nerves protruding

Question 2

Where does spinal cord terminate?

Answer 2

Conus medullaris (L1,L2), but bundle of nerves still continues going down as cauda equina

Question 3

What spinal column to coccyx?

Answer 3

Filus terminale

Question 4

Exiting nerve locations in thorasic vs cervical vertebrae?

Answer 4

Nerve is rostral to cervical vertebra

nerve is caudal to vertebra

Question 5

Dorsal roots vs ventral roots

Answer 5

Dorsal roots carry sensory into CNS, ventral roots carry motor out of CNS

Question 6

In vertebral column, gray vs white matter?

Answer 6

White matter on outside (send info up and down between levels on tracks), gray matter on inner part buterfly (has dorsal, ventral horns involved in sensory and motor processing) contain cell bodies,

Question 7

What part of white matter is the track that passes info up and down?

Answer 7

Funiculi (ventral, lateral, and dorsal funiculus)

Question 8

What info is carried by laminae I- IV

Answer 8

exteroroceptive

Question 9

What info is carried by laminae V and VI?

Answer 9

proprioceptive

Question 10

What info is carried by lamina VII?

Answer 10

Visceral motor neurons/autonomic ganglia

Question 11

What info is carried by lamina VIII-X?

Answer 11

motor

Question 12

Which spinal segments are the largest?

Answer 12

Cervical segments. Size of segments change depending on level and reflects function

Question 13

What is contained in the intermediolateral (IML) cell column?

Answer 13

found in lateral horns of thoracic segments which contain PRE-GANGLIONIC SYMPATHETIC neurons

Question 14

What is a ganglion?

Answer 14

Cluster of neurons that lie outside of CNS (i.e. cell bodies of sensory neurons reside in DRG)

Question 15

dermatome

Answer 15

region of skin supplied by right and left dorsal roots of a spinal segment

Question 16

Ascending vs descending tracts?

Answer 16

Descending = motor
asscending = sensory

Question 17

Dorsal column (ascending tract)

Answer 17

transmits mechanosensory info (gracile and cuneate fasiculs)

Question 18

Spinocerebellar tract

Answer 18

transmits proprioception info

Question 19

Spinothalamic tract (ascending tract)

Answer 19

transmits noiception, thermoreception

Question 20

Where do primary sensory neurons have cell bodies?

Answer 20

DRG

Question 21

Where do neurons containing sensory neurons in dorsal column medial lemniscal system synapse?

Answer 21

Enter spinal cord and ascend WITHOUT synapsing

Question 22

What do the spinocerebellar tracts convey?

Answer 22

Dorsal tracts convey nonconscious proprioceptive info about IPSILATERAL lower limbs to cerebellum

Question 23

Key feature of spinothalamic tract?

Answer 23

Pain and temperature info ascends contralaterally (while mechanosensory info ascends ipsilaterally)