Neuro Review- First Aid- pg 466 -472 Flashcards
sensory nerve ending –> cell body in dorsal root ganglion –> ipsilateral ascension in dorsal column of spinal cord –> ipsilateral nucleus cuneatus or gracilis in the medulla –> decussates –> ascend contralaterally in medial lemniscus –> VPL –> sensory cortex
dorsal column/medial lemniscus (DCML)
Adelta and C fibers (sensory nerve ending) –> cell body in dorsal root ganglia –> spinal cord –> ipsilateral gray matter –> anterior white commissure –> decussates –> ascends contralaterally –> VPL –> sensory cortex
spinothalamic tract (ALS)
ascending pressure, vibration, fine touch, proprioception tract?
dorsal column
What nerve roots mediate the cremasteric reflex?
L1-L2, testicles move
T10 dermatome
umbilicus
Dx?
- hemisection of spinal cord –>
- ipsilateral UMN signs BELOW level of lesion (corticospinal tract damage)
- ipsilateral loss of tactile, vibration, proprioception 1-2 levels below lesion (dorsal column damage)
- contralateral pain/temp loss below level of lesion (spinothalamic/ALS damage)
- ipsilateral loss of all sensation @ level of lesion
- ipsilateral LMN signs at level of lesion
- above T1 = can also have Horner syndrome (oculosypathetic pathway damage)
Brown-Sequard syndrome
polio
- cause = poliovirus (fecal-oral) –> destruction of cells in anterior horn of the spinal cord –> LMN death
- s/s = LMN signs (weakness, hypotonia, flaccid paralysis, fasciculations, hyporeflexia, muscle atrophy)
- CSF findings = increased WBCs, slightly increase proteins, normal glucose
What is the function of the lateral spinothalamic (ALS) tract?
ascending pain/temp
- UMN: 1a motor cortex –> descend ipsillaterally via internal capsule –> pyramids of caudal medulla –> decussate –> descend contralaterally –> anterior horn of spinal cord
- LMN: leaves spinal cord –> NMJ
lateral corticospinal tract
- Spinal cord problem = complete occlusion of anterior spinal artery
- characteristics = ?
only spares dorsal columns and Lissaur tract
What is the function of the superior colliculi?
conjugate vertical gaze (superior = sight)
descending voluntary mvmt of contralateral limbs tract?
lateral corticospinal tract
Brown-Sequard syndrome
- hemisection of spinal cord –>
- ipsilateral UMN signs BELOW level of lesion (corticospinal tract damage)
- ipsilateral loss of tactile, vibration, proprioception 1-2 levels below lesion (dorsal column damage)
- contralateral pain/temp loss below level of lesion (spinothalamic/ALS damage)
- ipsilateral loss of all sensation @ level of lesion
- ipsilateral LMN signs at level of lesion
- above T1 = also can have Horner syndrome (oculosypathetic pathway damage)
What is the function of the anterior spinothalamic tract?
- crude touch
- pressure
Dx?
- degeneration of dorsal columns and roots –> impaired sensation and proprioception, progressive sensory ataxia, poor coordination
- Charcot joints
- shooting pain
- Argyll Robertson pupils (small bilateral pupils that constrict to accommodation but not light)
- no DTRs
- positive Romberg test
- cause = 3a syphilis
tabes dorsalis
L4 dermatome
knees (down on all 4s)
What is the function of the lateral corticospinal tract?
descending voluntary mvmt of contralateral limbs
What is the pathway of the dorsal column tract?
sensory nerve ending –> cell body in dorsal root ganglion –> ipsilateral ascension in dorsal column of spinal cord –> ipsilateral nucleus cuneatus or gracilis in the medulla –> decussates –> ascend contralaterally in medial lemniscus –> VPL –> sensory cortex
What is the function of the dorsal column?
- ascending
- pressure
- vibration
- fine touch
- proprioception
tabes dorsalis
- degeneration of dorsal columns and roots –> impaired sensation and proprioception, progressive sensory ataxia, poor coordination
- Charcot joints
- shooting pain
- Argyll Robertson pupils (small bilateral pupils that constrict to accommodation but not light)
- no DTRs
- positive Romberg test
- cause = 3a syphilis
Dx?
- damage of anterior white commissure of spinothalamic (ALS) tract –> bilateral loss of pain/temp
- usually C8-T1
- Chiari 1 malformation
- can expand to affect other tracts
syringomyelia
T7 dermatome
xyphoid process
Amyotrophic Lateral Sclerosis (ALS) aka Lou Gehrig disease
- combined UMN and LMN deficits
- NO sensory, cognitive, or oculomotor deficits
- fasciculations –> atrophy and weakness
- tx = Riluzole to decrease presynaptic glutamate release (for Lou Gehrig, give riLOUzole)
- prognosis = fatal
- cause = maybe defect in superoxide dismutase 1?
What can cause Horner Syndrome?
spinal cord lesion above T1 (pancoast tumor, Brown-Sequard syndrome, late stage syringomyelia)
- Spinal cord problem = vitamin B12 or vitamin E deficiency
- characteristics = ?
- subacute combined degeneration –> demyelination of dorsal columns, lateral corticospinal tracts, and spinocerebellar tracts
- s/s = ataxic gait, paresthesia, impaired position/vibration sense
What is the pathway of the lateral corticospinal tract?
- UMN: 1a motor cortex –> descend ipsillaterally via internal capsule –> pyramids of caudal medulla –> decussate –> descend contralaterally –> anterior horn of spinal cord
- LMN: leaves spinal cord –> NMJ
What nerve roots mediate the anal wink reflex?
S3-S4, winks galore
crude touch, pressure tract?
anterior spinothalamic tract
What is the pathway of the spinothalamic tract (ALS)?
Adelta and C fibers (sensory nerve ending) –> cell body in dorsal root ganglia –> spinal cord –> ipsilateral gray matter –> anterior white commissure –> decussates –> ascends contralaterally –> VPL –> sensory cortex
ascending pain/temp tract?
lateral spinothalamic (ALS) tract
Babinksi sign in an adult could signify a ____ lesion.
UMN
Dx?
- combined UMN and LMN deficits
- NO sensory, cognitive, or oculomotor deficits
- fasciculations –> atrophy and weakness
- tx = Riluzole to decrease presynaptic glutamate release
- prognosis = fatal
- cause = maybe defect in superoxide dismutase 1?
Amyotrophic Lateral Sclerosis (ALS) aka Lou Gehrig disease
syringomyelia
- damage of anterior white commissure of spinothalamic (ALS) tract –> bilateral loss of pain/temp
- usually C8-T1
- Chiari 1 malformation
- can expand to affect other tracts
A spinal cord lesion above T1 (pancoast tumor, Brown-Sequard syndrome, late stage syringomyelia) can cause what syndrome?
Horner syndrome
What is the function of the inferior colliculi?
auditory
Dx?
- CSF findings = increased WBCs, slightly increased proteins, normal glucose
- LMN signs
polio
Dx?
- subacute combined degeneration –> demyelination of dorsal columns, lateral corticospinal tracts, and spinocerebellar tracts
- s/s = ataxic gait, paresthesia, impaired position/vibration sense
vitamin B12 or vitamin E deficiency
T4 dermatome
nipple line
