7 - spinal cord and spinal nerves Flashcards
(35 cards)
collections of cells bodys in CNS and PNS?
CNS - cortex and nucleus
PNS - ganglion
collections of axons (white matter) in CNS and PNS?
CNS - tracts, fascicle
PNS - nerve
where does the spinal cord end?
LI-LII (as conus medullaris)
is the spinal cord part of CNS or PNS?
CNS (but spinal nerves are part of the PNS)
where is the spinal cord the thickest?
cervical and lumbar enlargement
light coloured extension of the pia mater that anchors spinal cord to coccyx
filum terminale
the bunch of nerves that come off the conus medullaris is the …
cauda equina
what is the lumbar cistern and where is it?
LI/II to S1 - this is where there is subararchnoid space with cauda equina bathed in CSF
where is conus medullaris?
L1/2
where does spinal nerve C1 leave the column?
above vertebra CI, which why in the cervical region respective spinal nerves leave above the vertebra. Transition: C8 leaves below CVII –> respective thoracic spinal nerves leave below the vertebra
do respective spinal nerves leave above or below in cervical region
above (e.g. C1 above CI, C2 above CII etc)
do respective spinal nerves leave above or below their thoracic/lumbar etc vertebrae?
below (e.g. T1 below TI etc)
through where in the vertebrae do spinal nerves leave the column?
intervertebral foramen
As each spinal nerve leaves the vertebral canal it takes with it the meningeal coverings. These go onto form the …
epineurium
which of these spaces are real in the spinal meninges?
epidural
subdural
subarachnoid
epidural - fat
(subdural is potential)
subarachnoid - CSF
where is the conus meduallrs at birth and in adulthood?
birth - L2/3
adult - L1/2
so keeps extending even after birth
where do you retrieve CSF from? Safest place for needle?
Lumbar cistern (cauda equina move out of way) L3/4 or L4/5 - pierce ligamentum flavum (spinous processes)
blood supply of spinal cord. Think
- anterior
- posterior
- what does the aorta give off?
- reinforcers?
- deep SC and supplier of nerves
- the ant spinal travels in anterior median fissure > supplies anterior SC
- 2 post spinal - travel in post lat sulci
- segmental a - different given off by aorta depending on where in body
- medullary a - reinforces ant spinal
- radicular a - deep SC and also supplies nerves
divisions of white matter in the SC
Dorsal, lateral, ventral white columns
ventral white commissure
divisions of grey matter in the SC. What do they do?
dorsal - cell bodies of sensory
lateral - neurones for autonomic control (T1-L2, S1-S4)
ventral horns - cell bodies of motor
where is the lateral horn of the SC found?
T1-L2
S2-S4
the different parts that form or come from a segmental spinal nerve
dorsal and ventral roots –> (dorsal root and ganglion) (only root, no ganglion for ventral) –> dorsal and ventral roots join to form spinal nerve
difference between visceral and somatic sensory
som - from skin and skeletal muscles
vis - form internal organs, glands, blood vessels. usually pain/reflex signals
why is SC the reflex centre?
has interneurones, so can bypass brain
