Exam 2 Study Guide 6

Question 1

How is the SC organized?

Answer 1

by region (cervical, thoracic, lumbar, sacral, cauda equina)

Question 2

How are SC segments identified?

Answer 2

by same designation as their corresponding spinal nerves

1 segment = 2 vertebrae and the disc between them

Question 3

What are SC segments named for?

Answer 3

vertebral level where they exit the vertebral canal

Question 4

What structures comprise the spinal region?

Answer 4

all neural structures contained within the vertebrae

• spinal cord
• dorsal roots
• ventral roots
• spinal nerves (brief)
• meninges

Question 5

What structures comprise the spinal cord?

Answer 5

• columns
• horns
• grey matter
• white matter
• rexed lamina
• fissure
• sulci
• blood supply

Question 6

CSF located here

Answer 6

subarachnoid space

Question 7

organization of motor axons exiting the spinal cord

Answer 7

ventral rootlets form a ventral root

Question 8

dorsal root contains

Answer 8

sensory axons that bring info to the SC and enter it via rootlets

Question 9

large diameter sensory fibers (function)

Answer 9

proprioception and touch info

Question 10

Where are large diameter sensory fibers found?

Answer 10

medially

Question 11

small diameter fibers (function)

Answer 11

pain and temperature

Question 12

Where are small diameter sensory fibers found?

Answer 12

laterally

Question 13

Dorsal horn processes:

Answer 13

sensory info

Question 14

Lateral horn processe:

Answer 14

autonomic info

Question 15

Ventral horn processes:

Answer 15

motor info

Question 16

Most of the gray matter of the SC is composed of

Answer 16

spinal interneurons

Question 17

Where are lateral horns found?

Answer 17

T1-L2 segments

Question 18

What is a spinal nerve?

Answer 18

joining of a dorsal and ventral root in the IV foramen

carry all sensory and motor of a single spinal segment

Question 19

What are Rexed’s laminae?

Answer 19

functionally and structurally distinct areas of spinal cord gray matter

Question 20

tract: Contralateral fractionation of movement, particularly of hand movements

Answer 20

lateral CST

Question 21

tract: Control of neck, shoulder and trunk muscles

Answer 21

medial CST

Question 22

tract: Facilitates contralateral upper limb extensors

Answer 22

rubrospinal

Question 23

tract: Facilitates postural muscles and gross limb movements

Answer 23

reticulospinal

Question 24

tract: Adjusts activity in neck and upper back muscles

Answer 24

medial vestibulospinal

Question 25

tract: Ipsilaterally facilitates LMN’s to extensors, inhibits LMN’s to flexors

Answer 25

lateral vestibulospinal

Question 26

tract: Enhances the activity of interneurons and LMN’s in SC

Answer 26

ceruleospinal/raphespinal

Question 27

recurrent inhibition causes inhibition of these groups

Answer 27

• agonists

- synergists

Question 28

Loss of Renshaw cells creates

Answer 28

loss of fine motor skills