Motor Neuron Diseases

Question 1

associated symptoms of motor neuron lesions

Answer 1

table 3

Question 2

t/f on PE look for both umn and lmn lesion signs aside from weakness (atrophy, fasciculations, abnormal reflexes)

Answer 2

true

Question 3

common mnd mimics

Answer 3

myasthenia gravis
neurosyphilis
post-polio syndrome
thyroroxicosis

Question 4

lesions in als

Answer 4

umn and lmn

Question 5

lesions in pma

Answer 5

purely lmn

Question 6

lesions in pls

Answer 6

purely umn

Question 7

lesions in pbp

Answer 7

umn and lmn

Question 8

familial mutation in als

Answer 8

superoxide dismutase type 1 or sod 1

Question 9

t/f death occurs in als after 6 years of diagnosis

Answer 9

false, 2-5 years

Question 10

pathophysiology of als

Answer 10

unknown
motor neuron susceptibility factors can lead no mni
glutamate toxicity can lead to cell death

Question 11

el esocorial federation for diagnosis of als

Answer 11

signs of lmn and umn degeneration

progressive spread of signs with absence of ecg and imaging evidence

Question 12

revised el esocorial criteria

Answer 12

table 5

Question 13

awaji shima categories

Answer 13

table 6

Question 14

mri findings in als

Answer 14

used to exclude mnd mimics

hyperintensities or atrophy in precentral gyrus

Question 15

what is ncv

Answer 15

examines sensory and motor nerve action potentials

can distinguish axonal and demyelinating lesions

Question 16

results of axonal vs demyelinating lesions

Answer 16

axonal: abnormal or reduced amplitude of sensory or motor aps
demyelinating: abnormal latencies and/or conduction velocities

Question 17

ncv results of patient with als

Answer 17

sensory: normal
motor: normal conduction velocity, reduced amplitude

Question 18

what is emg

Answer 18

examines motor unit action potentials

discriminates neuropathic and myopathic source

Question 19

emg results in als

Answer 19

spontaneous activities (fasciculation, fibrillation, sharp waves)
motor unit aps are large
recruitment pattern is reduced

Question 20

pls vs pma

Answer 20

table 7

Question 21

pathophysiology of spinal muscular atrophy

Answer 21

autosomal recessive disorder caused by mutations in spinal motor neuron gene

Question 22

clinical manifestations of sma

Answer 22

weakness of varied severity depending on type and age of onset
proximal muscles more affected

Question 23

types of sma

Answer 23

1: werdnig-hoffman
2: dubowitz
3: wohlfart-kugelberg-welander
4: after 50

Question 24

pathophysiology of kennedy’s disease

Answer 24

adult onset sma

x linked recessive

Question 25

clinical features of kennedy’s disease

Answer 25

slowly progressive bulbar weakness and atrophy
proximal > distal
eom sparing
gynecomastia and testicular atrophy

Question 26

pathophysiology of hirayama disease

Answer 26

focal ischemic changes in anterior horn cells of lower cervical cord

Question 27

clinical features of hirayama disease

Answer 27

progressive wasting of muscles in hand and forearm
brachioradialis sparing
progresses then stabilizes

Question 28

pathophysio of acute poliomyelitis

Answer 28

due to poliovirus going through oral route to cns

• spinal cord (lumbosacral > cervical > thoracic)
• nucleus ambiguus, cn 5, 7, 12

Question 29

clinical features of acture poliomyelitis

Answer 29

minor: nonspecific
major: headache, fever, vomiting, malaise, neck and back stiffness, asymmetric weakness, hypo/areflexia

Question 30

clinical features of post-poliomyelitis syndrome

Answer 30

new onset 20-30 years after infection

fatigue, joint pains, muscle pain, weakness, atrophy

Question 31

associated cancer with paraneoplastic motor neuron disorder

Answer 31

subacute motor neuronopathy: lymphoma

paraneoplastic encephalomyelitis: sclc and (+) anti-hu antibodies

Question 32

anti-glutamate drug that can improve als prognosis

Answer 32

riluzole

Question 33

new drug to treat als

Answer 33

edavarone

Question 34

signs of poor prognosis in als

Answer 34

older
short interval between symptoms onset and diagnosis
weight loss
reduced pulmo function
muscle weakness
bulbar onset of disease