ANATOMY - spinal cord Flashcards
where are the 2 enlargements in the spinal cord
cervical - to supply the upper limbs
lumbar - to supply the lower limbs
at which vertebral level does the spinal cord stop
L1/2
below L1/2, what is there in the space where the spinal cord previously was
what is this called
nerve roots for L2-Co
cauda equina
where do you insert a needle for lumbar puncture
what happens when the needle is inserted
below L1/2
roots move to the sides
what is the filum terminale
the connective tissue between conus medullaris (end of spinal cord) to the coccyx
if the spinal cord has stopped, why are there still nerves in the vertebrae below L1/2
the nerves need to travel down to exit at the appropriate vertebral level
what are the spinal meninges, in order of external to internal
which 2 layers are stuck together
where is the CSF in relation to these layers
dura mater
arachnoid mater
pia mater
dura and arachnoid are stuck together
subarachnoid space - between arachnoid mater and pia mater
what surrounds the spinal meninges
epidural fat
what structures are contained within the epidural fat
internal vertebral extradural venous plexuses
how does the arrangement of white and grey matter differ in the spinal cord compared to brain
grey matter is internal
white matter is external
opposite to brain!
what is in white matter
how does this make it white
axons
covered in a myelin sheath = white
what shape is the grey matter in the spinal cord
H shaped
what are the 2 horns of the grey matter
anterior horn
posterior horn
what happens in the anterior horn of the grey matter
motor signals are sent out to body
anterior = want to be close to the action = motor signals
what happens in the posterior horn of the grey matter
sensory signals arrive from the body to go to the brain
what is in grey matter
neurons
what are the 4 main arteries that supply the spinal cord
anterior longitudinal arteries
2 posterior longitudinal arteries
segmental arteries
venous drainage is the same
where (in which layer) are the veins that drain the spinal cord
epidural fat
EPIDURAL/LUMBAR PUNCTURE
what is the first layer that the needle goes through
supraspinous ligament
EPIDURAL/LUMBAR PUNCTURE
what is the second layer that the needle goes through after the supraspinous ligament
interspinous ligament
EPIDURAL/LUMBAR PUNCTURE
what is the third layer that the needle goes through after the interspinous ligament
ligamentum flavum
EPIDURAL/LUMBAR PUNCTURE
what is the fourth layer that the needle goes through after the ligamentum flavum
epidural space - fat and veins
this is the final destination for epidural anaesthesia needles
LUMBAR PUNCTURE
what is the fifth layer that the needle goes through after the epidural space
dura mater
EPIDURAL/LUMBAR PUNCTURE
what is the sixth layer that the needle goes through after the dura mater
arachnoid mater (though basically tuck to dura mater)
EPIDURAL/LUMBAR PUNCTURE
what is the seventh layer that the needle goes through after the arachnoid mater
subarachnoid space
this is the final destination for lumbar puncture needles as they are collecting a CSF sample
where do you do a lumbar puncture at
L3/4
needs to be below L2 (as still spinal cord above that)
needs to be above sacrum (as sacrum is fused)
so needs to be L2-L5, go in the middle to be safe
what is a complication of both epidural anesthesia and lumbar punctures
epidural haematoma
extradural venous sinus damaged = compression of spinal cord/cauda equina
which one of the following is transected in a laminectomy;
anterior longitudinal ligament posterior longitudinal ligament annulus fibrosus ligamentum flavum dura mater
ligamentum flavum
main blood supply
anterior spinal artery
