Spinal cord Flashcards
where do spinal nerves originate and what do they become
emerge between vertebrae and bifurcate into doral and ventral rami
what are peripheral nerves
orginate from dorsal and ventral rami
how do peripheral nerves get mixed
in plexuses
how are bilaterally paired spinal nerves named
according to their vert - C1 begins above C1
where do spinal nerve axons come from
cell bodies in the spinal level
what is a dermatome
area of skin innervated by a spinal level
what is a myotome
muscles controlled by a given spinal level
what does pattern of peripheral nerve vs. dermatome tell us
where the lesion is located
4 special areas of spinal cord and what they help us localize
C3-5: phrenic - descending resp control
T1-L2: Sympathetic preganglionic Ns: control of temp and visceral functions
S2-4: Pelvic splanchnic nerves: PNS innervation of pelvic viscera
S2-4: pudendal nerve: somatic sense and motor to the perineum etc.
**key dermatomes to know
C2: back of head C5: shoulder tip C6: thumb C7: middle finger C8: small finger T4: nipple T10: umbilicus L1: inguinal ligament L5: great toe S1: small toe and sole S5: perianal
what is end of spinal cord and at what level
conus medullaris - L2
wha is mass of nerves at end of L2
cauda equina
what is final string at end of cord
filum terminale
what is lumbar cistern
expanded subarachnoid space bw L2 and S2
what is clincal relevance of cistern
where lumbar puncture is done
what are denticulate ligaments and what do they do
expensionsof pis mater that anchor cord laterally to dural sac
what fills the epidural space
fat and blood vessels
what are 4 spinal cord sulci
- ventral median fissure
- ventral lateral sulcus
- dorsal lateral sulcus
- dorsal median sulcus
what are 3 columns of white matter
ventral, lateral, dorsal
what are 2 horns of grey matter and what do they contain
ventral: sensory
dorsal: motor
what are 2 areas of ventral hor enlargement
cervical (C5-T1) for arms
lumbosacral (L2-S3) for the legs
what are intermediolateral cell columns
lateral horns that contain SNS Ns at T1-L2 and PNS Ns at s2-4
how does white matter change at levels
decrease as go caudally
where are cell bodies of sensory neurons
in dorsal root ganglions
what is function of ventral horn neurons
somatic motor (somatic)
what is function of IML neurons
visceral motor (autonomic)
what do spinal nerves carry
both sensory and motor neurons
