Neuroanatomy Practical 4: Spinal Cord and Spinal Nerves

Question 1

Where does the subarachnoid space terminate superiorly?

Answer 1

Lateral to the Superior Sagittal Sinus

Question 2

Which level, approximately, is the cervical enlargement located?

Answer 2

C6/C7

Question 3

What type of information is carried in the spinothalamic tract?

Answer 3

Pain
Temperature
Touch

Question 4

When do the fibres running through the dorsal column pathway cross the midline?

Answer 4

After they have passed through the C/GC

Question 5

When does the fibres running through the spinothalamic tract cross the midline?

Answer 5

Immediately after they enter the spinal cord

Question 6

Where does the epidural space end inferiorly?

Answer 6

sacral hiatus at the level of S4

Question 7

Which of the pathways runs ipsilaterally and which runs contralaterally in the cord?

Answer 7

Spino: contra laterally

Dorsal: ipsilaterally

Question 8

Where do dorsal and ventral roots unite to form the spinal nerves?

Answer 8

Intervertebral foramen of the vertebra number below unless in the cervical region

Question 9

Where does the epidural space end superiorly?

Answer 9

Foramen magnum

Question 10

Which of the following carries sympathetic fibres back to spinal nerves?

Grey Rami Communicans
White Rami Communicans

Answer 10

Grey

Question 11

Where does the spinal cord terminate in the adult?

Answer 11

L1/L2

Question 12

What is the dorsal rami of the spinal nerve?

Answer 12

First branch off the dorsal side of the spinal nerve

Mixed nerve

Motor: deep muscles in the back

Sensory: general sense and proprioceptive sense from muscles, tendons and joints

Question 13

What surface landmarks would you use to determine the point to insert the needle during a lumbar puncture?

Answer 13

Posterior tip of spinous process in line with the ASIS

Question 14

Name three conditions where the composition of the CSF is altered?

Answer 14

Meningitis

Encephalitis

SA Haemorrhage

Tumours

CJD

etc

Question 15

What type of information is carried by the dorsal column pathway?

Answer 15

Touch
Vibration
Position

Question 16

What is the ventral rami of the spinal nerve?

Answer 16

The first branch off the ventral side of the spinal nerve

Mixed nerve

Motor: skeletal muscle of neck, trunk and extremities

Sensory: skin of trunk and extremities. Proprioceptive sense from muscles, tendons and joints between T1-L2

Question 17

What does the SA space contain?

Answer 17

CSF

Question 18

What is the functional difference between the dorsal and ventral nerve roots?

Answer 18

Ventral - Motor

Dorsal - Sensory

Question 19

Where does the subarachnoid space terminate inferiorly?

Answer 19

S2

Question 20

What other structure terminates at the inferior termination level of the subarachnoid space?

Answer 20

Lumbar cistern

Question 21

How are sympathetic fibres connected to the spinal nerves?

Answer 21

Via white and grey rami communicans

Question 22

Where is the most common site from which CSF is sampled?

Answer 22

Lumbar cistern

Question 23

What determines whether the fibres ascend in the gracile or the cuneate fascicle?

Answer 23

Origin above or below T6

Question 24

Which level, approximately, is the lumbar enlargement?

Answer 24

T11

Question 25

List the layers, from superficial to deep, punctured by the needle during a lumbar puncture

Answer 25

Skin
Fascia and SC fat
Supraspinous lig.
Interspinous lig.
Ligamentum flavum
Epidural space and fat
Dura
SA Space

Question 26

How many spinal segments are there?

Answer 26

30 (33 more if you include the Co)

Question 27

Why is the patient asked to assume the foetal position when a lumbar puncture is required?

Answer 27

Widens the lumbar cistern

Question 28

Which section has the most white matter?

Answer 28

Cervical

Question 29

What is the procedure used to obtain a sample of CSF from the lumbar cistern?

Answer 29

Lumbar puncture

Question 30

What do the fibres of the spinothalamic tract and dorsal column pathway travel in?

Answer 30

Spino: spinal leminuscus

Dorsal: medial lemniscus

Question 31

Where does the spinal cord terminate in the neonate?

Answer 31

L3

Question 32

What happens to the amount of white matter as your ascend the spinal cord and why is this?

Answer 32

It increases due to an amalgamation of ascending fibres as you ascend the body