Spinal Cord Flashcards Preview

Neuro Physiology > Spinal Cord > Flashcards

Flashcards in Spinal Cord Deck (33)
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1
Q

Which layers cover the spinal cord?

A

Dura, subarachnoid, pia

2
Q

Which layer contains CSF?

A

Subarachnoid. Central canal contains CSF.

3
Q

What is the function of the spinal cord?

A

Provides autonomic innervation of most viscera.

4
Q

Where does the spinal cord end?

A

Between first and second lumbar vertebrae. Ends as filum terminale.

5
Q

What structure forms as the spinal cord tapers off?

A

Conus medullaris

6
Q

What name is given to the spinal nerves that arise from the end of the spinal cord?

A

Cauda equina

7
Q

Name the 4 columns of the spinal cord.

A

Dorsal horn
Ventral horn
Intermediate column
Lateral horn

8
Q

What is the function of the dorsal horn?

A
  1. Contains neurones that receive somatosensory information from the body.
  2. Transmits information via ascending pathways to the brain
9
Q

What is the function of the ventral horn?

A

Contains motor neurones that exit the spinal cord to innervate skeletal muscle.

10
Q

What are the functions of the intermediate column and lateral horn?

A

Contain neurones that innervate visceral and pelvic organs.

11
Q

What does the spinal nerve divide into when it leaves the vertebral canal?

A

Posterior and anterior rami

12
Q

What are the 31 paired spinal nerves?

A

8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal

13
Q

Is the dorsal root sensory or motor?

A

Sensory

14
Q

Is the ventral root sensory or motor?

A

Motor

15
Q

Which arteries supply the spinal cord?

A

Anterior spinal artery > Paired posterior spinal arteries > Anterior and posterior segmental medullary arteries

16
Q

Which veins drain the spinal cord?

A

Anterior and posterior spinal veins > Internal and external vertebral plexuses

17
Q

Which stain is used to stain white matter black?

A

Osmium. Stains myelin.

18
Q

Which stain is used to stain grey matter black?

A

Silver stain. Stains cell body.

19
Q

How many laminae are in grey matter?

A

10

20
Q

Is the fasciculus gracilis an ascending or descending tract?

A

Ascending.

Carries proprioception and vibration information from the lower body to gracile tubercle in medulla.

21
Q

Is the fasciculus cuneatus an ascending or descending tract?

A

Ascending.

Carries proprioception and vibration information from upper body to cuneate tubercle in medulla.

22
Q

Is the spinothalamic tract ascending or descending?

A

Ascending.

Lateral side carries pain & temperature information. Medial side carries crude touch information. Both sides ascend on the same side for 1/2 segment, decussate and join at the medulla. Cell bodies are in dorsal root ganglion.

23
Q

Is the lateral corticospinal tract ascending or descending?

A

Descending.

Begins in primary motor cortex. Medulla decussation. Transmits control of voluntary limb muscles.

24
Q

Is the ventral corticospinal tract ascending or descending?

A

Descending.

Begins in primary motor cortex. Decussates as it leaves the anterior white commissure. Transmits control of voluntary axial muscles.

25
Q

What are fasiculi?

A

Nerve axons running up and down the spinal cord in bundles.

26
Q

What are upper motor neurones and what do they do?

A

Neurones that originate in the cerebral cortex and brainstem. They control movement, muscle tone, spinal reflexes.

27
Q

What are lower motor neurones and what do they do?

A

Neurones that originate in the anterior grey column, cell bodies in brainstem. They receive signals from UMN and transmit these to muscle fibres.

28
Q

Upper motor neurones are divided into two types. Give these.

A

Pyramidal and extrapyramidal.

29
Q

What are pyramidal UMN?

A

2 neurone pathway that originates in the cerebral cortex. Decussate in the medulla and descend contralaterally. Synapse with cell bodies of the ventral horn of the spinal grey matter.

30
Q

What are extrapyramidal UMN?

A

Originate in brainstem. Carry motor fibres to spinal cord. Responsible for involuntary autonomic control of all musculature.

31
Q

Name the 4 sensory nerve endings that can sense fine touch.

A
  1. Meissner’s corpuscle
  2. Pacinian corpuscle
  3. Ruffini endings
  4. Merkel endings
32
Q

What is Brown-Sequard syndrome?

A

A hemi-section of the spinal cord.

33
Q

What occurs as a result of Brown-Sequard syndrome?

A

Ipsilateral loss of: proprioception, motor & fine touch a few segments below the level of damage. Descending corticospinal tract is damaged.
Contralateral loss of: pain, temperature & crude touch a few segments below the level of damage.