Anterior Horn and Periph Nerve Disorders Flashcards
UMN injury produces what symptoms
1) spasticity
2) hyeprreflexia
3) Babinski
4) emotional lability (inappropriate laughing/crying)
LMN injury produces what symptoms
1) muscle atrophy
2) fasciculations
3) decr tone
4) decr or absent reflexes
all motor neuron, NMJ and muscle diseases have no ___
sensory changes accompanying the weakness
sensory changes imply ___ disorders
nerve root
plexus
or peripheral nerve
ex of rapdily developing weakness
NMJ disorders like
MG
botulism
organophosphate poisoning
disease caused by acute remissions and relapses
myasthenia gravis
proximal weakness most characteristic of
muscle disorders
difficulty climb stairs get up from low chairs raise arms over head broad gait lordotic posture, wide gait
distal weakness of hands and feet + distal sensory loss most characteristic of
neuropathies
with slapping, footdrop gait
difficulty with fine hand movements
cranial weakness involving extraocular, facial, oropharyngeal muscles seen in
+ ptosis, double vision, dysphagia
Myasthenia graivs
disuse of a limb such as bedridden or fracture produces ___
atrophy but retained strength
old people can still be strong even with muscle atrophy
myaglia and tenderness with muscle inflamm seen in
polymyositis
myotonia involves
stiffness due to delayed relaxation of muscle after voluntary contractions
muscle cramps due to
involuntary contraction of muscle and benign
diseases assoc with skeletal muscle deformitis such as socoliosis, club foot, contratures (loss of ROM)
neuromuscular disorders
rhabdomyolysis and myoglobulia seen when?
inability to generate ATP d/t glycogen or lipid metabolic defects
best lab value for muscle necrosis
highest in what dz
mod in what dz
incr serum creatine kinase
highest with myoglobinuria
moderate with muscular dystrophies and inflamm myopathies
nerve condition studies used to differentiate btwn
1) primary demyelinating (very slow)
2) axonal neuropathies (fast)
needle EMG perfoermed when___
complement to NCS for differentiating myopathic from neuropathic disorders
neuropathic disorders (anterior horn cell and peripheral nerve) = loss of whole motor units
myopathic disorders = drop out of fibers within motor unit
repetitive stim of nerve in MG produces
decr in amplitude of compound muscle AP
ALS due to ?
majority are sporadic or genetic?
degeneration of brainstem and spinal cord LMN
+ spasticity, hyperreflexia from UMN injury
2) sporadic
symptoms of ALS
1) asymmetric limb weakness + fasciculations
2) footdrop
3) contracture from inteorsseous wasting
4) UMN signs
5) sensory normal
6) slurred speech
7) spared facial muscles
8) diaphragm weakness
Treatment of ALS
1) Rilouzole
2) braces for mobility
Charcot Marie Tooth
2 catgories
1) demyelinating neuropathy = CMT 1
2) axonal degeneration = CMT2
Difference btwn CMT1 and CMT2
1) slow NCV
2) normal NCV
inheritance of CMT1 and CMT2
CMT4
autosomal dominant
recessive
CMT1A due to what molecularly?
duplication of PMP22
deletion of PMP22 causes what?
HNPP
3 phenotypes of CMT
1) most common = onset walking normal but distal weakness/sensory loss in 20’s
2) impaired as infants with delayed walking
3) adult onset at 40 y/o
Diabetic neuropathies
what kind of neuropathies
patients with asymptomatic diabetes may show ___ NCVs that normalize with ___
most common neuropthy
can be poly, mono, plexo, radiculo
may show decr NCVs normalized with improved blood sugar control
most common subtype of diabetic neuropathy
distal sensory or sensorimotor polyneuroapthy
- numbness + burning dysesthesias in feet –> spread up legs and into hands
- slapping foot drop gait
- decr grip str, decr fine dexterity
examination of paitent with diabetic neuroapthy
pin sensation loss in stocking globe distrib but asymm
loss of position, vibr, light touch, decr reflex in ‘LARGE FIBER’
pain and temp loss + pain in ‘SMALL FIBER’
autonomic symptoms of neuroapthy
1) postural hypotension
2) diarrhea
3) impotence
4) urinary retention
5) incr sweating
lumbosacral plexopathy is characterized by
onset when?
1) acute onset asymm prox weakness and leg pain
occurs at onset of diabetes and assoc with weight loss
mononeuropathies can affect what?
carpal tunnel
ulnar peroneal
+ CN (3rd and 6th nerve palsies
pathogenesis of diabetic neuroapathies
1) metabolic derangements and change in endoneural vessels + ischemia
2) occlusion of small nutrient blood vessels supplying nerves
tx for autonomic symptoms of diabetic neuropathy
1) codeine + diphenoxylate for diarrhea
2) stockings
3) fluorocortisone or midodrine for postural hypotenison
4) voiding assisted by pressure for bladder atony
tx for cramps/spasticity in ALS
hydration
benzodiazepans
phenytoin
quinine
lioresal
dantrolene
gabapentin
helps jaw quiver/clench; incr weakness; decr FVC
tx for pseudobulbar affect in ALS
TCA and SSRI
dextromethorphan + quinidine
tx for drooling, thick phlegm, and laryngospasms
decr saliva
metoprolol and propranolol for thick saliva
decongestants
tx for sleep distrubance in ALS
multiple causes
avoid short acting sedatives
test for desaturation = nocturnal NIPPV
sx of sensory or sensorimotor distal polyneuropathy
stocking/glove numbness and burning pain
foot drop and weak hand muscles
sx of autonomic neuropathy in diabetic neuropathy
1) hypotension
2) diarrhea
3) impotence
4) urinary retention
sx of mononeuropathy in diabetic neuropathy
CN 3, 6, 7 or peripheral (median, ulnar, peroneal)
sx of lumbosacral plexopathy
pelvic girdle pain
asymm hip flexor weakness
