Spinal cordfunction and dysfunction

Question 1

How many spinal segments are there?

Answer 1

31

Question 2

How many spinal pairs? What vertebrae types are they?

Answer 2

31 pairs. 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal

Question 3

Where do nerves leave the cord?

Answer 3

Through the intervertebral foramina.

Question 4

Where are vertebral enlargements for limb innervation located?

Answer 4

Cervical - C3-T1 Lumbar - L1-S3

Question 5

Are spinal/vertebral levels consistent with one another?

Answer 5

No.

Question 6

Vertebral cross section. Label meningeal converings.

Answer 6

Question 7

What is the function of the epidural space?

Answer 7

Space between dura and vertebral periosteum. Fat filled. Venous plexus.

Question 8

What is the function of arachnoid matter?

Answer 8

Lines the dura.

Question 9

What is the function of the pia mater?

Answer 9

Adhere tightly to surface of spinal cord.

Question 10

What is the function of the subarachnoid space?

Answer 10

CSF filled. Continuous with subarachnoid space of brain.

Question 11

What is the function of the dura mater?

Answer 11

Form dural sac. Extend to S2. Continuous with innder sheet of dura in cranium.

Question 12

What is the anterior root?

Answer 12

Carry motor information. Exit spinal cord through anterolateral sulcus.

Question 13

What is the posterior root?

Answer 13

Carry sensory information. Cell bodies in spinal ganglion. Enters spinal cord at posterolateral sulcus.

Question 14

What is the spinal ganglion?

Answer 14

Contains cell bodies of sensory afferents. Also pseudounipolar neurons. No synapses.

Question 15

What is the difference between spinal white an grey matter?

Answer 15

Grey matter - cell bodies

White matter - tracts.

Question 16

Where can spinal anaesthetic be administered?

Answer 16

Needle into subarachnoid space. Between 3rd and 4th lumbar vertebrae.

Question 17

Where can epidural anaesthetic be administered?

Answer 17

Into epidural space. Between 4th and 5th lumbar vertebrae.

Question 18

Define dermatome and myotome.

Answer 18

Dermatome - area of skin innervated by one spinal nerve/spinal segment

Myotome - muscles innervated by one spinal nerve/segment.

Question 19

Label cross section of spinal cord.

Answer 19

Question 20

What is the function of the posterior median sulcus?

Answer 20

Divide posterior spinal cord surface into two halves.

Question 21

What is the function of the anterior median fissure?

Answer 21

Divide the anterior surface of the spinal cord into two halves.

Question 22

Label diagram to show common nervous roots to and from spinal cord.

Answer 22

Question 23

What is the difference between a root and a ramus.

Answer 23

Roots contain nerves of only one type (e.g. sensory/motor), ramus contain both.

Question 24

Label major tracts of the spinal cord.

Answer 24

Question 25

Understand schematic of corticospinal tract (cortex-spine)

Answer 25

Question 26

Diagram to show pathway of sensory information from skin to cortex.

Answer 26

Question 27

Outline the dorsal column pathway. What is conveyed?

Answer 27

Discriminative touch, vibration, proprioception.

Question 28

Outline the spinothalamic tract pathway. What does it convey?

Answer 28

Pain and temperature.

Question 29

Where is ANS SNS flow focused?

Answer 29

T1-L2 spinal segments

Question 30

Where is ANS PNS slow focused?

Answer 30

Brainstem, cranial nerves (III, VII, IX, X).

S2-S4 spinal segments

Question 31

Name 3 factors determining severity of spinal lesions.

Answer 31

1. loss of neural tissue
2. vertical level
3. transverse plane.

Question 32

What are the most common causes of spinal injuries?

Answer 32

Road traffic accidents, sports, falls.

Question 33

Identify the stages of injury to lateral corticospinal tract.

Answer 33

• Stage 1. Spinal shock: loss of reflex activity below the lesion, lasting for days or weeks = flaccid paralysis
• Stage 2. Return of reflexes: hyperreflexia and/or spasticity = rigid paralysis

Question 34

How is the location of symptoms determined in unilateral lesions?

Answer 34

the relationship of the deficit to the lesion depends on where the tract decussates

Question 35

Diagram to outline ipselateral/contralateral damage.

Answer 35

Brown-Sequard