SPINAL CORD Flashcards Preview

Neuroanatomy > SPINAL CORD > Flashcards

Flashcards in SPINAL CORD Deck (52)
Loading flashcards...
1
Q

What are the two enlargements in the spinal cord

A

cervical enlargement

Lumbosacral enlargement

2
Q

The ___ innervates the upper limb

A

brachial plexus

3
Q

The ___ innervates the lower limb

A

lumbosacral plexus

4
Q

At what vertebral level does the spinal cord end

A

L1/L2

5
Q

Are vertebral level and spinal cord level the same

A

no

6
Q

Spinal nerves exit the spinal cord at ___

A

their respective vertebral level

7
Q

What tethers the spinal cord to the coccyx

A

cauda equina

8
Q

What tethers the spinal cord at every level

A

denticular ligaments

9
Q

What occurs to spinal cord in thoracic segment

A

anterior horns are much smaller - fewer motor neurons coming out here - only a few myotomes are only a couple core muscles

10
Q

What synapses in the lateral horn

A

visceral motor fibres

11
Q

What occurs to spinal cord in the lumbar segment

A

less white matter, because thoracic has motor and sensory tracts for whole body while lumbar is just lower body

12
Q

3 main functions of the spinal cord

A
  • Conduit (pathways to and from the brainstem and cortex-white matter tracts)
  • Reflexes
  • Locomotion - Central pattern generators
13
Q

What is transmitted in fasciculus gracilis? where in the spinal cord is it?

A

Found in medial dorsal column. Transmits sensory - fine touch, proprioception) from ipsilateral lower limb

14
Q

What is transmitted in fasciculus cuneatus? where in the spinal cord is it?

A

Found in lateral dorsal column. Transmits sensory (fine touch, proprioception) from ipsilateral upper limb

15
Q

What is transmitted in spinocerebella tract? where in the spinal cord is it?

A

Found in posterior lateral column. Proprioception from limbs to cerebellum

16
Q

What is transmitted in lateral corticospinal tract? where in the spinal cord is it?

A

Found in medial lateral column. Motor to ipsilateral ventral horn - mostly limb musculature

17
Q

What is transmitted in Spinothalamic tract? where in the spinal cord is it?

A

Found in the anterior lateral horn. Transmits pain and temperature from contralateral side of the body

18
Q

What is transmitted in anterior corticospinal tract? where in the spinal cord is it?

A

Found in ventral column. Transmits motor to ipsi- and contralateral ventral horn mostly axial musculature

19
Q

Does the lateral or anterior corticospinal tract cross in the brainstem

A

lateral

20
Q

Where does the lateral corticospinal tract cross? What % of the corticospinal tract is this

A

in the medulla (pyramidal decussation) 80%

21
Q

Where does the anterior corticospinal tract cross? what % of the corticospinal tract is this

A

in spinal cord at anterior white commissure. 20% of fibres

22
Q

The corticospinal tract originates in the…

A

primary motor cortex

23
Q

Where in the brainstem do the corticospinal tract fibres travel

A

anterior brainstem

24
Q

What tract is primarily responsible for compensating for balance

A

vestibulospinal tracts

25
Q

How does the vestibulospinal tract compensatre for balance

A

It stabilizes neck musculature and innervates flexors and extensors of lower limb to withstand gravity

26
Q

what is muscle tone

A

continuous contraction, readiness of a muscle

27
Q

What determines muscle tone

A

activity of muscle spindles

28
Q

What is the function of the vestibulospinal tract

A

maintaining balance, postural control, muscle tone

29
Q

What is the function of the reticulospinal

A

postural control, muscle tone

30
Q

What is the function of the tectospinal tract

A

directing eyes and head&neck to object of interest

31
Q

What are central pattern generators

A

automated sequence of motor neuron activation to allow for locomotion: generation of repetitive cycles of flexor and extensor activation

32
Q

What are 2 ways that CPGs can respond to environmental cues

A
  1. Proprioceptors regulate timing to stepping patterns

2. Skin receptors allow for adaptation to obstacles

33
Q

Signals travel from bladder to where to signal that it is full

A

Cortex and Periaqueductal grey

34
Q

What is the role of the cortex in bladder control

A

sample environment to ensure appropriate setting. if appropriate, activates pontine micturition centre

35
Q

What does the pontine micturition centre do once activated by the cortex

A

inhibits sympathetics and somatic motor

Activates parasympathetic

36
Q

What is the result of the pontine micturition centre inhibiting sympathetics

A

Internal sphincter relaxation (in males)

37
Q

What is the result of the pontine micturition centre inhibiting somatic motor

A

relaxation of external sphincter

38
Q

What is the result of the pontine micturition centre activating parasympathetics

A

contraction of the detrusor muscle

39
Q

Is there cortical control of the bladder in infants

A

no

40
Q

What is the sacral reflex of bladder control

A

when the bladder is full to a certain point it will just contract the detrusor

41
Q

What is the problem encountered with the sacral reflex of bladder control

A

you are contracting against a closed sphincter - does not fully empty bladder

42
Q

At what level does the spinal cord end

A

L1-L2

43
Q

What is the epidural space filled with

A

Fat and venous plexus

44
Q

The denticulate ligaments separate…

A

the posterior and anterior roots

45
Q

What is the entry point for posterior roots carrying sensory information

A

posterolateral sulcus

46
Q

What is the exit point for anterior roots carrying motor information

A

Anterolateral sulcus

47
Q

Why do the cervical and lumbar regions have more gray matter

A

these regions innervate the limbs, motor neurons for all limb muscles are located at the levels as are snesory nerves

48
Q

Segmental arteries branch to form…

A

posterior/anterior radicular arteries and segmental medullary arteries

49
Q

Radicular arteries supply…

A

anterior/posterior spinal roots at each level

50
Q

Anterior spinal artery supplies the _____

Posterior spinal artery supplies the ____

A

anterior 2/3

posterior 1/3

51
Q

Visceral motor neurons of the sympathetic nervous system are located within ___ segments

A

T1-L2

52
Q

Visceral motor neurons of the parasympathetic nervous system are located within ___ segments

A

S2-S4 s