Neuromuscular Flashcards
(120 cards)
0
Q
What syndrome / nerve involvement? pain in arm/forearm weak thumb, 2nd, 3rd finger flexion NORMAL sensation Can't make "ok" sign
A
anterior interosseus syndrome (pure motor nerve branch of median)
1
Q
What sensory area should be spared in carpal tunnel?
A
sensation over thenar eminence b/c palmar cutaneous branch arises proximal to tunnel.
2
Q
what might be prolonged on nerve conduction studies for carpal tunnel?
A
median sensory study distal latency (before motor NCS abnormal)
*Both may be normal on routine NCS
3
Q
Muscle to test to ddx ulnar neuropathy from T1 radiculopathy and why? What movement?
A
test abductor pollicis brevis b/c its innervated by median nerve and would be involved in T1 radiculopathy but not ulnar neuropathy.
4
Q
What are the 4 branches of the posterior cord?
A
STAR: Subscapular, Thoracodorsal, Axillary, Radial
5
Q
What does a lesion of the posterior cord cause?
A
sensory loss of posterior arm/hand, weak shoulder abduction, weak extension fingers, wrist, elbows
6
Q
what nerve is responsible for supination of forearm, brachioradialis reflex and extension of thumb, fingers, wrist, elbow?
A
radial nerve
7
Q
extensor carpi ulnaris is innervated by what?
A
Radial: all extension! (even though ulnaris is in the name.)
8
Q
Humerus fracture can affect what nerve?
A
radial
9
Q
Saturday night palsy affects what?
A
radial neuropathy at spiral groove
10
Q
What does radial palsy from spiral groove look like?
A
wrist and finger drop, weak supination, lateral dorsal hand sensory loss, SPARED elbow extension b/c triceps innervated before the spiral groove
11
Q
Ddx radial neuropathy at axilla vs spiral groove
A
axilla will involve the triceps and will cause sensory loss of posterior forearm and arm vs radial groove which spares triceps, and causes sensory loss of hand only.
12
Q
anterior and posterior interosseus neuropathy have what feature that distinguishes from median/radial neuropathy
A
No sensory loss (motor nerves only)
13
Q
what does the axillary nerve supply? What functions?
Injured by what?
A
deltoid and teres minor, upper lateral arm sensory
Injured with humerous frx and also shoulder dislocation
14
Q
nerve responsible for cremasteric reflex, and the roots?
A
genitofemoral L1-L2
15
Q
what is compressed in meralgia paresthetica?
What does it cause
What causes it
A
lateral femoral cutaneous nerve
causes paresthesias of lateral thigh
from tight clothes, pregnancy, obesity, weights at waist
16
Q
nerve injured in childbirth and what does it cause?
A
loss of sensation and adduction of medial thigh
Obturator: AAP GOP
Adductor brevis, longus, magnus
Gracilis, obturator externus, pectineus
17
Q
What sx of complete sciatic paralysis?
A
knee flexion, ankle, toe movement
sensation lateral knee, lateral/post calf, lateral foot, dorsum/sole of foot
ankle reflex
18
Q
hip surgery, dislocation, fracture, or intramuscular buttock injection can injure what nerve?
A
sciatic
-prob w/ hamstrings, adduction of hip, posterior and lateral sensation
19
Q
what is piriformis syndrome?
A
sciatic compressed against piriformis and causes buttock pain
20
Q
what nerve allows you to tiptoe?
A
tibial nerve
21
Q
What is tarsal tunnel syndrome
What nerve
what sx
A
tibial nerve neuropathy or branches in the tarsal tunnel
Causes burning pain in ankle and foot, and perimalleolar pain worse with weight bearing and at night
22
Q
crossing legs can result in what nerve injury?
A
superficial common peroneal nerve at fibular head
23
Q
Which type of muscle are fast, fatigue resistant?
A
2a
24
which type of muscle fiber are slow and use oxidative metabolism for steady contraction?
type 1
25
What type of muscle fibers are fast and fatiguable but provide big force/
2b
26
episodes of weakness lasting hours or days triggered by large carbo load or exercise is caused by what gene mutation usually and what is the inheritance and name of dz?
hypokalemic periodic paralysis
1q31 mutation in Ca channel
AD
27
what is most likely genetic cause of hyperkalemic periodic paralysis
- what channel and gene
- what inheritance
- when does it present?
SCN4A alpha subunit of Na channel on skeletal muscle
periodic paralysis in kids <10y, symmetric lasting min-hrs triggered by rest AFTER exercise or fasting; relieved by carbs and lt exercise
Chr 17q23
28
hypoK/hyperK match:
better with carbs/after light exercise
worse with carbs/exercise
Na channel
Ca channel
Chr 1
Chr 17
HypO K: worse with carbs and with exercise, chr 1q31 for Ca channel
HypER K: beTTER with carbs/REst after exercise, chr 17q23 SCN4A, Na channel
29
Mutation and channel defect in myotonia congenita
muscle chloride channel CLCN1, Chr 7q
30
Disease triggered by cold with myotonia?
paramyotonia congenita
31
what makes paramyotonia congenita para?
it actually worsens with exercise as opposed to the myotonia congenitas that improve with repeated muscle activity
(often eyelids don't open after first strong blink.)
32
newborn with hip dislocation, clubfoot, hypotonia, weakness?
| Dx and likely genetics/inheritance
Central Core disease congenital myopathy
| -AD, RYR1 chr 19q13. (also cause malignant hyperthermia)
33
Patient with hypotonia, muscle weakness, ptosis and extraocular muscle weakness
centronuclear myotubulular myopathy (CN- includes CN)
34
Dx w/ resp distress, severe hypotonia at birth, high arched palate, narrow face?
Path?
Nemaline rod myopathy
| 0muscle EM: rods originate from Z discs
35
limb girdle weakness and purple eyelid rash and periorbital edema
- what antibodies
- what classic path
- what tx?
anti Jo-1 Ab
perifascicular atrophy
steroids tx
36
what immune systems mediate dermatomyositis and polymyositis respectively?
dermato: humoral
poly: T cells
37
Pt w/ weakness in finger flexors and quads, slightly elevated CK, older man?
inclusion body myositis
38
Classic pathology in inclusion body myositis?
endomysial inflammation, eosinophilic cytoplasmic inclusions, rimmed vacuoles**, amyloid deposition
39
Tx for inclusion body myositis?
does NOT respond to immunomodulatory meds
40
3 classic EMG findings in myositis:
1. incr insertional activity
2. low amp short duration motor unit action potentials
3. early recruitment of motor unit action potentials
41
rimmed vacuoles on muscle bx EM?
inclusion body myositis
42
the muscle disease that affects fingers, distal ue muscles uniquely and quads.
IBM (sitting at computer) inclusion body myositis
43
the myopathy not associated with increased insertional activity on EMG?
steroid myopathy (type 2 fiber atrophy)
44
med that can cause a mitochondrial myopathy with ragged red fibers?
AZT/Zidovudine
45
mild proximal weakness with muscle cramps, myoedema, delayed reflexes, muscle enlargement, myokymia, very elevated CK
Dx?
hypothyroid myopathy
46
characteristics of icu/critical illness myopathy
pts on steroids/nmj blockers get flaccid paralysis, areflexia, vent-dependent, loss of myosin, SPARED extraocular muscles and sensation
47
Difference in bx results in steroid myopathy vs critical illness myopathy
steroid: loss of 2b fibers (*see dark type 1 fibers, not light 2 fibers)
critical illness: loss of myosin
48
Inheritance for congenital muscular dystrophy?
AR
49
Inheritance for Facioscapulohumeral muscular dystrophy
AD
50
Inheritance for Emery-Dreifuss muscular dystrophy
X-linked recessive, AD, or AR (think X linked most likely)
51
Inheritance for oculopharyngeal muscular dystrophy?
AD
52
Inheritance for Limb girdle muscular dystrophy
AD or AR
53
Differentiate two forms of congenital muscular dystrophy: Merosin positive and negative
+: less common, less severe, may ambulate, no white matter abnormalities on T2brain MRI, Chr 6 (MeroSIX)
-: more common, more severe, no walking, progressive contractures
54
Syndromic congenital muscular dystrophy with chromosome 9q31-33 mutation?
Fukuyama disease
55
syndromic muscular dystrophy in Finland with defect in POMGnT1 on Chr 1p32?
Muscle-eye-brain disease
56
Disease with POMT1 mutation on chr 9q34?
Walker Warburg syndrome
57
In general, the syndromic congenital muscular dystrophies are due to what?
hypoglycosylated alpha-dystroglycan
58
Distal myopathy which affects gastroc and soleus involving mostly posterior compartment of legs, spares extensor digiti minimi but has very high CK? Genetics?
Miyoshi myopathy with defect on chr 2p13
| My sushi is a gastronomical delight
59
This muscle disorder results in early elbow and ankle contractures, toe walking, and cardiac abnormalities that can lead to sudden death
Emery Dreifuss Muscular dystrophy
60
Humeroperoneal distribution of weakness and heart prob?
Emery Dreiffus
61
Popeye effect? Seen in what dz?
weak bicep/tricep but strong and big deltoid and distal arm muscles seen in FSHD: fascioscapulohumeral muscular dystrophy
62
FSCH usually presents at what age
by age 20y
63
Asymmetric weakness of face, scapula muscles, proximal upper extremities, and foot dorsiflexion.
Can't whistle, use a straw, close eyes tightly.
FSHD
64
Think of marching band guy who can't hear, scapula wing, he can't march, he may wear a marching band coat, and he can't play the trumpet anymore. What disease and genetics?
FSHD: scapular winging, hearing loss, AD chr 4q D4Z4 deletion.
Weak mouth/face, Popeye effect, and may be assoc w/ COATS disease: exudate telangiectasia and retinal detachment
65
Autosomal dominant vs recessive limb girdle muscular dystrophy
AD: type 1
AR: type 2
66
DX with myotonia, facial and distal weakness, multiple organs involved including apathy, christmas tree cataracts, heart probs, GI / swallow probs, frontal balding, hypersomnia, hypogonadism, hypoventilation, insulin resistance
Genetics?
myotonic dystrophy 1: CTG repeat in DMPK on chr 19q13.3 (AD)
67
EMG in myotonic dystrophy?
myotonic discharges, myopathic muscle fiber action potentials
68
path in myotonic dystrophy
type 1 fiber atrophy, increased central nuclei
69
likely dx w/ neck weakness, temporal/masseter weakness, ptosis, dysphagia, weak eye and mouth closure, other organs involved
myotonic dystrophy type 1
70
What is the most common myopathic disorder to present in neonatal period and what is the genetics?
congenital myotonic dystrophy with >1000 CTG repeats on chr 19q13 due to anticipation. Mom might have myotonic grip
71
Neonatal EMG in congenital myotonic dystrophy
does not yet show myotonia
72
What distinguishes myotonic dystrophy type 1 from type 2?
Type 2 is known as proximal myotonic myopathy (PROMM) and is primarily proximal and can have calf pseudohypertrophy. LEss cardiac/lung involvement, less atrohphy. Is a tetranucleotide repeat of CCTG (extra C: closer to proximal)
73
Asymmetric ptosis, progressive extraocular muscle weakness without diplopia and mild neck/prxoimal limb weakness.
oculopharyngeal muscular dystrophy
74
genetics of oculopharyngeal muscular dystrophy
Muscle path?
autosomal dominant GCG repeat in PAPB2 on chr 14q11.
(GCG: gag choke gag from dysphagia)
bx shows rimmed vacuoles and fiber size variation
75
episodes like Reye's syndrome, progressive weakness, cardiomyopathy
Dx and what does the muscle bx show?
primary systemic carnitine def.
| bx shows lipid storage
76
most common metabolic cause of recurrent myoglobinuria?
CPT-II deficiency on chrom 1
| see pee tea with too much exercise
77
The glycogen storage diseases all have what inheritance and what is the exception?
all autosomal recessive except phosphoglycerate kinase deficiency which is X-linked recessive
78
What is another name for acid maltase deficiency?
Pompe disease / Glycogen storage disease type 2
79
This disease starts in 20-30s and p/w fatigue, leg/trunk weakness and respiratory failure and myotonia in paraspinal muscles
Dz, CNS risk, and bx findings?
Acid maltase deficiency, intracranial aneurysms due to glycogen deposition, vacuolar myopathy on bx
80
second wind phenomenon?
McArdle's disease Glycogen storage disease type V
81
2 diseases with exercise intolerance and myoglobinuria?
| How to distinguish?
Mcardle dz AND
| TArui disease / phosphofructokinase def GSD VII and abnl FILT test, but NO second wind phenomenon
82
Classic emg / ncs finding in infantile botulism
posttetanic facilitation and absence of posttetanic exhaustion
83
repetitive stim at what Hz causes potentiation in botulism?
20-50 (Hi freq)
84
dz w/ dry mouth and proximal muscle weakness in which strength temporarily increases with exercise?
LEMS
85
CMAP decrement with repetitive stimulation at 2-5Hz?
Seen in Myasthenia
86
increased jitter and blocking on single fiber EMG in what?
Myasthenia
87
what major meds should be avoided in myasthenia?
5 major: aminoglycosides, procainamide, quinine/quinidine, magnesium, beta blockers
88
pts w/ anti-MUSK instead of anti-ACHR Ab in myasthenia have what treatment features?
less response to anticholinesterase meds and htymectomy less helpful
89
In a pt w/ GBS looking picture but Miller fisher variant with ophthalmoplegia but NORMAL CSF, think what?
tick paralysis
90
dz with hypohidrosis, decreased tears and saliva, GI issues and impotence and pain
Dx and defect?
Fabry's alpha-galactosidase def
91
syndrome that may be assoc w/ carpal tunnel that also involves heart probs and lower limb pain, and autonomic difficulties?
Familial amyloid polyneuropathy (FAPO) from transthyretin defect
92
CMT 1: type of neuropathy and inheritance?
demyelinating and AD
93
CMT II: type of neuropathy and inheritance
Axonal AR
94
Inheritance and type of neuropathy of CMT III
Demyelinating AR
95
Deletion vs duplication of CMT I and HNPP
Deletion of PMP-22 in HNPP
Duplication of PMP-22 in CMT IA
(Duplication: 2 of them, two abnormal pes cavus feet)
96
Multifocal motor neuropathy with conduction block is known fo what clinical feature presentation and what lab test?
asymmetric distal weakness and atrophy in UE
| Anti-GM2 antibodies
97
What is POEMS?
```
Polyneuropathy
Organomegaly
Endocrinopathy
M protein (monoclonal gammopathy)
Skin changes
```
98
What is the deficiency in Tangier disease and what is the genetics? What are the sx? What do labs / bx show?
ABCA1 on chr 9q31, deficiency of alpha lipoprotein (dx w/ very low HDL)
sensory neuropathy of distal upper extremities and atrophy of intrinsic hand muscles, large orange tonsils, LAD/splenomegaly
(hold a tangerine in your hand where atrophy occurs)
Path: macrophages w/ cholesterol esters
99
upper trunk plexopathy? presentation?
Erb-Duchenne, waiter tip
100
Lower trunk plexopathy? and sx?
lower trunk rare plexus injury with claw like deformity and possible Horner's
101
What are the features (2) of radiation induced plexopathy?
prominent pain and myokymia
102
First EMG finding in AIDP?
LOss of F waves
103
What is a poor prognosis AIDP, and what are the markers and associations?
AMAN: acute motor axonal neuropathy. Assoc w/ Campylobacter, anti-GD1 and anti-GM1 ABs
104
What is the Miller Fischer variant of AIDP/GBS?
triad of opthalmoparesis, ataxia, areflexia
105
Dx in patient with significant weight loss, pain, asymmetric proximal weakness of quads and psoas predominantly
diabetic amyotrophy
106
Characteristic EMG of radiculopathy?
even though sensory complaints in dermatomal distribution, the SNAPs are normal on EMG/NCS w/ lesions proximal to the =DRG
107
Acute radiculopathy might show what in the first 2 weeks only on EMG/NCS
fibrillations in paraspinal muscles
108
UMN/LMN disease SPARING extraocular muscles and sensation?
ALS
109
What do you see on pathology of ALS?
loss of motor neurons in cord, brainstrem sparing extraocular; loss of Betz cells, fiber-type grouping and muscle atrophy, atrophy of motor and anterior roots of spinal cord
110
Bunina bodies are what and seen in what?
eosinophilic cytoplasmic inclusions in ALS
111
Med for ALS and what needs to be monitored?
| What is proposed mechanism?
Riluzole, watch LFTs
| inhibits relase of glutamate, and there are high glutamate levels in CSF in ALS
112
Gene for familial ALS?
SOD1 gene on chr 21q22.1
113
What is Fazio-Londe syndrome? features?
juvenile progressive bulbar palsy with facial weakness, dysarthria, dysphagia, lingual fasciculations (think of face fonze / londe: funny speech in london)
114
Another name for spinobulbar atrohpy?
Kennedy's X-linked spinobulbar muscular atrophy
115
What causes Kennedy's disease genetics, and what is the clinical presentation? major DDX?
CAG expansion of Androgen receptor gene
muscle cramps, face weakness/fasciculations, proximal limb weakness, dysarthria/swallowing issues, decr reflexes, hormonal issues.
DDX ALS but NO UMN signs
116
Gene for SMA?
5q11
117
SMA that doesn't walk but sits?
SMA II
118
Type of SMA with walkers, when do they present?
after 18 mos, often get scoliosis
119
Most common cause of recurrent myoglobinuria?
Carnitine palmitoyltransferase deficiency
