spinal cord and tracts Flashcards
what are the meninges
dura arachnoid
pia
how is dura in head
attached to skull
how is dura in cns
loose - space around
what is in the epidural space
fat and veinous drainage
what is defining feature of arachnoid
spidery projections onto pia
where do you get csf from
sub-arachnoid space
what is in subarachnoid space
csf
what might lumbar puncture test for
meningitis
what is in grey matter
cell bodies, synapses
what is in white matter
myelinated stuff ie axons
what are the areas of white matter called
funiculi
how many funiculi are there
3
what are the funiculi names
posterior lateral anterior
where do sensory nerves go in
dorsal horn
where do motor nerves come out
ventral horn
defining feature of cervical area spinal column transverse section
lots of white, large dorsal and ventral horns of grey
where is cauda equina
below l1/2
how do find l1
one vertebra below last rib
where do vertebral arteries come off
subclavian
where do vertebral arteries run
Transverse foramina
what do 2 vertebral arteries joining together in brain make
basilar artery
vertebral arteries also supply what going downwards?
anterior and posterior spinal arteries
anterior and post spinal arteries are really tiny,. how are they helped out?
intercostal arteries feed into them
What is the defining feature of thoracic spinal cord in transverse section
lateral horn of grey matter
where does spinothalamic tract decussate
at the level of spinal cord it enters
sensations of spinothalamic tract
crude pain. temperature
where is spinothalamic tract
anterior, slightly lateral
what is pain sensation called
nociception
what is a nociceptor
pain receptor
what are the 2 types of spinothalamic receptors
A-delta
C
where do 2ary spinothalamic neurones go
nucleus proprius to thalamus
where do 3ary A delta spinothalamic neurones go
thalamus to primary somatosensory cortex
what do A delta fibres feel
fast pain, accurate location and duration of pain, sharp
what do C fibres feel
slow pain, lots of activations, intensity=action potentials
what are 4 spinothalamic receptor types
thermo- mechano- chemico- polymodal
where is the A delta fibres
lateral STT
where are the C fibres
anterior STT
where is the anterior STT thalamic relay
intralaminar nuclei of thalamus
where does 3ary C fibres go (4)
intralaminar nucleus of thalamus to 2ary somatosensory cortex
parabrachial nucleus of pons -> limbic system
posterior medial nucleus of thalamus -> arousal/focus
midbrain reticular formation -> spinal reflexes
where does shingles live
sensory dermatomes
what is the blood supply to the STT
anterior spinal artery
which is the only tract supplied by the anterior spinal artery
STT
what are the functions of the DCML
light touch, proprioception, 2 point discrimination, vibration
where do you take lumbar puncture
subarachnoid space - csf l4/l5
where to you take epidural?
outside dura mater
where does DCML decussate
lower medulla
what are the decussation fibres of DCML called
internal arcuate
what is the DCML tract up to the brain caleld
medial lemniscus
what does the D of DCML refer to
DORSAL bit of spinal column
what are the two fasciculi of DCML and where do they come from
gracilis, medial, legs/genitalia
cuneatus, lateral, arms
how do you test DCML proprioception? Name?
can you keep your balance with eyes closed? Romberg’s test
what is spinocerebellar tract
spine->cerebellum
where does spinocerebellar tract decussate
it doesn’t
what does spinocerebellar tract function
unconscious propriception
which important cranial nerve feeds into DCML
trigeminal
where does VPM nucleus of the thalamus receive information from
nociception from head and face
where does VPL receive information from
nociception from rest of body
what is relay from thalamus to 1ary somatosensory cortex part of
internal capsule
where have most DCML receptors
fingertips, lips, tongue
