Nervous System Overview - Spinal Cord Anatomy

Question 1

The spinal cord runs from the […] to […] in adults.

Answer 1

Brainstem

L2

Question 2

Spinal nerves exit the spinal cord between […] and […]

Answer 2

C1 and L2

Question 3

Answer 3

1 - Spinal cord

2 - Cauda Equina

3 - Conus medullaris

4 - Filum terminale

Question 4

The […] is the most inferior part of the spinal cord and is located at approximately […] in adults

Answer 4

Conus medullaris

L1/L2

Question 5

Spinal nerves that exit below the conus medullaris are called the […]

Answer 5

Cauda Equina (b/c they look like a horse’s tail)

Question 6

What is the role of the filum terminale?

Answer 6

It anchors the conus medullaris to the sacrum

Question 7

The […] is the most internal layer covering the spinal cord.

Answer 7

Pia mater

Question 8

The […] is the intermediate layer covering the spinal cord.

Answer 8

Arachoid mater

Question 9

The […] is the most external layer covering the spinal cord.

Answer 9

Dura mater

Question 10

The […] is the space between the pia and arachnoid mater.

[…] is located in this space.

Answer 10

Subarachnoid space

CSF

Question 11

The […] is the space between the dura mater and arachnoid mater.

Answer 11

Subdural space

Question 12

The […] is the space outside the dura mater.

Answer 12

Epidural space

Question 13

Answer 13

1 - spinal cord

2 - arachnoid mater

3 - subarachnoid space

4 - dura mater

5 - subdural space

6 - anterior rootlets

Question 14

• Epidural anesthesia and is delivered in the […] at level […]
• Another location where an epidural can be administered is the […]

Answer 14

Epidural space

L3/L4

Sacrum

Question 15

A lumbar puncture is done in the […] space at level […]. This procedure is to obtain […].

Answer 15

Subarachnoid space

L3/L4

CSF

Question 16

Why are epidurals and lumbar puncture done at L3/L4?

Answer 16

Becuase the fibers of the cauda equina will move out of the way of needles that are inserted here so there is less risk of doing damage to CNS tissue if done here than higher up in the spine.

Question 17

Where is the conus medularis in a newborn/infant?

Answer 17

Usually ~ L3

Question 18

How does height affect the location of a person’s spinal cord anatomy?

Answer 18

A taller person will have their conus medularis more superior compared to an average height adult. Shorter adults will have their conus medularis more inferior copared to an average height adult. This happens b/c cauda equina does not grow at same rate as vertebra during development.

Question 19

Describe the structure of the nervous system (tree diagram)

Answer 19

Question 20

How many pairs of cranial nerves are there?

What information do they carry?

Answer 20

12

Somatic sensory, somatic motor, or autonomic (usually parasympathetic) –> can be a single one of these or a mix

Question 21

• How many spinal nerves are there?
• All […] signals to and from muscles are carried by branches of […] nerves
• Some spinal nerves carry […] or […] also

Answer 21

• 31
• somatic; spinal
• Sympathetic; parasympathetic

Question 22

Of the 31 spinal nerves, […] are cervical, […] are thoracic, […] are lumbar, […] are sacral and […] is coccygeal

Answer 22

8

12

5

5

1

Question 23

The brachial plexus consists of spinal nerves between […] and […]

Answer 23

C5 and T1

Question 24

The intercostal nerves consist of spinal nerves between […] and […]

Answer 24

T1 and T12

Question 25

The lumbosacral plexus consists of spinal nerves between [...] and [...]

Answer 25

L2 and S4

Question 26

* For cranial nerves, C1 - C7 exit the vertebral column [...] the vertebral bodies they correspond to and C8 exits [...] C7. * All other spinal nerves exit the vertebral column [...] the vertebral bodies they correspond to.

Answer 26

* Above; Below (between C7 and T1) * Below

Question 27

Dorsal rami innervate the [...] muscles and [...] receive names.

Answer 27

Intrinsic back Do not

Question 28

Ventral rami innervate [...] and [...] receive names.

Answer 28

All other muscles Do

Question 29

Spinal nerves and rami carry only motor information. True/False

Answer 29

False - they carry motor information to the muscles they innervate and sensory information from the muscles back to the spinal cord

Question 30

The ventral horn and root/rootlets carry only [...] information.

Answer 30

Motor

Question 31

The dorsal horn and root/rootlets carry only [...] information.

Answer 31

Sensory