Spinal Cord Review Flashcards
What is neural tube formation affected by
folic acid in the 1st trimester
what is the neural tube derived from
ectoderm
how does the spinal cord start and at what week
starts distal to the 4th pair of somites in the 3rd week of gestation
At what week does the neural tube close
4th week of gestation
how long is the spinal cord (start + finish)
begins at foramen magnum and ends at L1/2
Where is the regional enlargement of the spinal cord
cervical (c6) and at lumbosacral regions
what is the 3 coverings of the spinal cord from outside to inside
outer- dura mater
middle- arachnoid with subarachnoid under w CSF
inner- pia mater with hilum terminal and two dentate ligs which anchor the spinal cord to spinal dura
where does the dural sac end
@S2
What coverings of t psinal cord extend along with the spinal nerves
dura and arachnoid extend along the spinal nerves as they pass thru the IVF
what do the posterior section of the the spinal cord carry up (what type of info)
vibration, fine touch and jt pos sense
Fasicculus gracilis vs fasicculus cunateus
gracilis lower limb
cunateus upper limb
what does the spinocerebellar path carry
unconscious proprioception
what does the spinothalamic path carry
pain, temp, crude touch and pressure
Fasicuculs gracilis/ cunatus- 1st order neutron, 2nd order, decision,3rd order
vibration, fine touch, jt pos sense
2nd- nuclei gracilis and cuneatus
decussion- medulla
3rd- VPL nucleus of thalamus
Spinothalamic- 1st, 2nd, decussion, 3rd order neutrons
1- temp, crude touch, pressure
2- lamina 1/2
decussion- spinal cord
3- VPL nucleus of thalmus
Dorsal spinocerebeller- 1st, 2nd, decussion, 3rd order neutron
- unconscious prop from lower limb
2- clarkes nucleus
- DOES NOT CROSS
- cerebellum via inf cerebeller peduncle
Ventral spinocerebeller- 1st, 2nd, decussion, 3rd order
1- unconscious prop from both lower + upper limb
2- lamina 7
decussion- twice- first at spinal cord then again at pons (stays ipsilat)
3rd- cerebellum via sup cerebellar peduncle
Lateral corticospinal- function, 1st, decussion, 2nd order
fun- voluntary control of mm in limbs
1st- precentral gyrus
dec- medulla
2nd- lamina 4-9
Ventral corticospinal- function, 1st, dec, 2nd order
voluntary control of mm in head, neck and trunk
1- precentral gyrus
dec- spinal cord at level of exit
2- lamina 6-9
RUbrospinal function, 1, dec, 2nd
eis prox flexprs and inhibits extensors mainly in Upper limb
1- red nucleus
dec- midbrain
2- lamina 5-8
Reticulospinal - function, 1, dec, 2
restricts voluntary mvmts thru gamma motor neuorns
1- reticular formaton
dec- various levels
2- lamina 8
Tectospinal- function, 1st, dec, 2nd
function- head and eye turning in response to light and sound
1st- tectum of midbrain
dec- midbrain
2nd- lamina 6-8
Vestibulospinal- function, 1st, decussion, 2nd
involved in postural reflexes (neck, extensors)
1- vestibular nuclei
dec- uncrossed
2- lamina 6-8
where is the intermediallateral horn found in the spinal cord
T6-L1- represents region that carries sympathetic fibres
what does the lamina 1 carry
contains neurone which synapse with the first order neurone and sends axons to CL spinothalmic tracts
What is found in high concentrations in lamina I, II
Substance P, a neuropeptide involved in pain sensibility
What is laminae 3 and 4 + what does it carry
nucleus proprius
-main input is from fibres that carry mechanoreception and light touch
What does lamina VI receive
receives mechanical signals from skin and joints
what is laminae VII and what does it carry
dorsal nucleus of clarke
-carry unconscious proprioception
Laminae VIII and IX represents what
motor neurone groups in the ventral horn
what is the blood supply of the spinal cord from
segmental spinal arteries that give rise to radicular and segmental medullary arteries
what does the segmental medullary artery give rise to and what do they supply
single ant spinal (supplies ant 2/3 of spinal cord)
Two post spinal (supply post 1/3 of spinal cord)
UMN- reflexes, tone, atrophy, fasciculation’s, Babinski
reflexes- increased w clonus
tone- spastic
atrophy- absent
fasciculation’s- absent
babinski- presnet
LMN lesion- reflexes, tone, atrophy, fasiculations, babinski
reflexes- decreased/absent
tone- Flaccid
Atrophy- presnent
Fasiculatins- present
Babinski- absent
