LECTURE 9: spinal region Flashcards
when do the spinal rami start?
in the PNS
what are Small groups of axons of lower motor neurons that leave SC thru anterolateral sulcus that join to form ventral nerve root
ventral rootlets
Ia and A β for fine touch & proprioception are apart of what?
dorsal rootlets medial
A delta and C for pain and temperature are apart of what rootless
lateral dorsal rootlets
what Anchor SC along its length to dura mater, to each side and each segment to help keep teh SC from moving
Denticulate ligaments
what is in the white matter
axons
what is in the gray matter
cell bodies
what is the propriospinal tract
axons that originate and terminate within the SC
where is the propriospinal tract in the SC
surround the gray matter
what are Long axon cells that carry info connecting spinal cord and brain
tract cells
nucleus dorsalis/ clarie’s column extends vertically from
T1-L3
what does the clark’s column/ nucleus dorsalis receive
proprioceptive info and sends to cerebellum (unconscious)
1st order neurons of spinothalamic tract synapse here
substantial gelatinosa
preganglionic autonomic neurons are ____ leaving the SC thru _____ ____
Preganglionic autonomic neurons are efferent, leaving the SC thru ventral root
which levels aer the epidural anesthesia injected in and what space
L3 & L4 and epidural space
where is the spinal anesthesia injected into
subarachnoid space
the segmental spinal arteries supplement anterior spinal and posterior spinal arteries thru what
segmental medullary arteries
segmental spinal arteries give rise to ________ which follow and supple dorsal and ventral ____
Give rise to anterior and posterior radicular arteries which follow and supply dorsal and ventral roots
what do central pattern generators input in
automatic rhythmic motor activities
can the SC develop neuroplasticity and motor learn, even without cortical in put
yes
what are stepping pattern generators
a type of central pattern generators
reciprocal coordination of stepping occurs from communication thru what
SC’s anterior commissure
Receptors from skin, muscles, and/or joints can transmit ____ information to cause different kinds of withdrawal mvmts
afferent (withdrawal reflex)
what is reciprocal inhibition
Inhibits activation of antagonist muscle while activating agonist muscles
when does reciprocal inhibition occur
during reflexive and voluntary muscle activity
inputs to reciprocal inhibitory inter neurons come from what tracts
Corticospinal, rubrospinal, and vestibulospinal tracts
what are the 3 CNS levels needed from urinary continence
frontal cortex, pons and sacral cord
if bladder is full, but situation is inappropriate to void, frontal cortex tells ____ tract to
control pelvic floor muscles to compress the bladder neck and assist external sphincter
corticospinal
if it is okay from you to pee what foes the frontal cortex disinhibit
the pons which signals parasympathetic neurons to contract bladder wall and relax internal sphincter
what syndrome causes flaccid paresis of lower limb muscles , bladder and bowels
cause equina syndrome
during tethered cord syndrome, if it effects the anterior cauda equina then what sign is that
lower motor neuron signs
if there is excessive stretch of spinal cord in tethered cord syndrome than what signs show
upper motor neuron signs
what is tethered cord associated with
spina buffa myelomeningocele (L4 , L5 , S1)
what marks the end of spinal shock
return of anal reflexes
Spinal neurons can become _____, developing hyperreflexia as
neuroplasticity develops new synapses in reflex pathway
hyperexcitable
what causes flaccid areflexive bladder
Injury at S2-S4
Injury above S2-S4 interrupts _____ tracts causing hypertonic, hyperreflexive bladder
descending
after spinal injury , fertility returns to what for men and female
male : low sperm counts and low fertility
women: return to normal
spastic cerebral palsy may require selective
dorsal rhizotomy
what is multiple sclerosis
progressive demyelinating disease of CNS
cord compression due to
spinal canal stenosis and Syringomyelia
