Neuro 5 - Spinal cord and nerves anatomy

spinal cord location

spinal cavity within the vertebrae

divisions of the spinal cord

where does spinal cord proper end

inferior border of L1

non-neural structures that support the spinal cord and functions

meninges, conus medularis (attachment point for filum terminale), filum terminale (fibrous tissue that anchors spinal cord)

spinal nerves nomenclature

named after the vertebrae they exit below (exception: C1-C7 which exit above their corresponding vertebrae)

cauda equina

large collection of long nerves that extend from the end of the spinal cord

conus medularis function

end of spinal cord
point of attachment for filum terminale

filum terminale function

anchors spinal cord

where does sensory info travel in spinal cord

up dorsal column into dorsal horns

damage to dorsal horn/nerve

loss of sensation on the same side

where do motor commands travel in spinal cord

down ventral column from ventral horns

damage to ventral horn/nerve

paralysis/muscle weakness on the same side

once spinal nerves leave the dorsal column they…

ramify (branch)

3 types of rami

dorsal ramus, ventral ramus, ramii communicans/sympathetic ganglion

damage to spinal nerve

loss of sensation and paralysis on the same side

dorsal root ganglion contains

sensory neuron cell bodies

white matter contains

myelinated axons

dorsal nerve root contains

sensory neuron axons

ventral nerve root contains

motor neuron axons

ventral horn contains

autonomic neurons and somatic neurons

hole in centre of spinal cord

central canal

groove in the back of the spinal cord

posterior median sulcus

groove in the front of the spinal cord

anterior fissure

epineurium

outermost layer of connective tissue surrounding peripheral nerve

perineurium

layer surrounding fascicle

endoneurium

layer surrounding myelinated axon

fascicle

small bundle of nerve fibers

other components of peripheral nerve

blood vessels