Neuromuscular Flashcards
what nerve provides sensation to the first web space of the foot?
deep peroneal nerve (branch of common peronial, which is a branch of the sciatic)
what nerve provides sensation to the upper and lateral part of the lower leg?
common peroneal n. (branch of the sciatic n.)
what nerve provides sensation to the lower lateral part of the lower leg and the doral medial foot?
superficial peroneal n.
what nerve innervates the volar (palmar) surface of digits 1-3
median nerve
what sphincter is under voluntary control for micturition?
external urethral sphincter
what is the innervation of the external urethral sphincter (and form what spinal level does it arise)?
motor neurons from Onu’f nucleus in the anterior horn of S2-S4.
most usefull muscle to test to distinguish muscles of the upper brachial plexus and the lateral chord.
Teres Minor
where is cerebral voluntary control of micturition located?
Frontal micturition center in the paracentral lobule.
What is innervation of the internal urethral sphincter and detrusor muscle?
Sympathetic inputs from T11-L1 cause bladder neck contraction.
What is the innervation of the internal urethral sphincter?
sympathetic.
what are the 4 EMG features of CIDP?
- Conduction block, 2. temporal dispersion, 3. prolonged distal latency, 4. slowed conduction.
Protein involved in LGMD 1B, inheritence, and clinical feature
Lamin A/C, AR, Cardiac arrhythmias
Protein in LGMD 1c, inheritence, and clinical correlate
Caveolin-3, AR, rippling muscle disease
protein in LGMD 2A, inheritence, and clinical presentation
Calpain-3, AD, scapular winging, rectus abdominal weakness, hamstring weakness.
Protein in LGMD 1A, inheritance and clinical presentation
Myotilin, AR, adult onset, distal predominance
protein in LGMD 2B, inheritance, and clinical feature
Dysferlin, AD, posterior calf atrophy
LGMD’s that make up 10% of all LGMD, inheritance, and proteins
LGMD 2C, D and E, AD, sarcoglycans
Protein in LGMD 2G, inheritance, and clinical feature
Telethonin, AD, quadriceps and anterior tibial weakness
Protein in LGMD 2J, inheritance, and clinical feature
Titin, AD, can be distal
What LGMD results in walker warburg disease when severe, and what protein is involved?
LGMD 2K, POMT1
What LGMD results in fukuyama disease when severe, and what protein is involved?
LGMD 2L, Fukutin
what LGMD results in muscle eye brain disease when severe and what protein is involved?
LGMD 2M, POMGnT1
which type of motor neuron causes muscle contraction?
alpha
what type of motor neuron innervates intrafusal muscle fibers? What is its role?
gamma afferents- maintains 1alpha efferent firing during contraction.
what type of muscle fiber afferent (aka sensory n.) prevents muscle over-contraction during muscle firing?
1b afferents. arise from golgi organs in the msucle.
what are the 3 muscles innervated by the musculocutaneous nerve?
1.coracobrachialis, 2. brachialis, 3. biceps
what movements are weak with musculocutaneous n. injury? Fibers from what nerve root travel in this nerve?
- elbow flexion 2. supination with the arm flexed at the elbow but NOT with the arm extended.
C5,6 and 7
where does numbness occur with musculocutaneous nerve injury?
lateral part of fore arm.
what type of injury causes musculocutaneous nerve injury?
anterior shoulder dislocation.
what is the age of onset of oculopharyngeal muscular dystrophy?
30s-60s
What is the trinucleotide repeat, gene and chromosome in oculopharyngeal muscular dystrophy?
GCN (where N can be any amino acid), PABN1, 14q11.1
what is the nucleotide repeat, gene, and inheritance in myotonic dystrophy type I?
CTG, DMPK, AD, 19q13.2
what is the nucleotide repeat, gene, and inheritance in myotonic dystrophy type II?
CCTG, ZNF9, AD Chr 3
what myopathy is depicted?

Nemeline myopathy
what are the 3 EMG features of Myasthenia Gravis?
- greather than 10% decrement in CMAP with repetitive 3 Hz stimulation. 2. Single fiber EMG “jitter” 3. neuromuscular blockade
What disorder causes sensorimotor neuropathy, upper motor neuron signs, gait characterized by walking on insides of feet, and tightly curled hair? What are the pathologic findings?
Giant axonal neuropathy. Large focal axonal swelling that contain tightly packed disorganized neurofilaments.
What are the two late responses in NCV studies?
F-wave and H-response
How is an F-wave obtained?
Supramaximal stimulation of a motor nerve while recording from a muslce. The impulse travels first antidromically (opposite normal direction) and then backfires and travels orthodromically (normal direction).
How is the H-wave obtained and what reflex arc does it represent?
Stimulate tibial nerve at the popiteal fossa while recording at the soleus. Represents S1 reflex arc.
what 3 things affect CMAP amplitude?
- motor axon 2. NMJ 3. muscle fibers
What is the Motor unit potential (MUP) finding in chronic denervating lesions?
Large polyphasic MUPs
In what disorders is insertional activity increased?
Denervation and myotonic disorders
What are the 5 types of spontaneous muslce activity?
- fibrillation potentials
- fasciculation potentials
- myokymia
- myotonic potentials
- complex repetitive discharges
spontaneous rhythmic depolarizations of individual muscle fibers.
fibrillation potentials, seen in myopathies and neuropathies.
spontaneous depolarizations of a single motor unit
Fasciculation potentials. seen in neuropathic disorders.
adjacent, abnormal muscle fibers depolarizing each other. Machine sound on EMG
complex repetitive discharges. Seen in myopathies and acute neuropathies
spontaneous rapid depolarization of an individual msucle fiber
myotonia, seen in myotonic disorders
Brief, rhythmic bursts of electrical activity originating from the motor unit
Myokymia. Seen in demyelinating neuropathies and radiation neuropathies.
what is recruitment in EMG studies?
number of MUPs firing during voluntary muscle contraction
What EMG findings occur in early axon loss lesions?
decreased recruitment.
What EMG findings occur in myopathic processes?
early or rapid recruitment with excessive short, small amplitude MUPs.
Time course of fibrillation potentials after denervating injury.
3 weeks
time course of large, polyphasic MUPs after denervating injury
3-6 months
What are the SNAP findings in myasthenia gravis?
Normal
does myasthenia gravis affect presynaptic or post-synaptic membrane?
post-synaptic
where is the defect in neurotransmission in Lambert Eaton Myashthenia Syndrome?
pre-synaptic
what are the 4 nerve conduction findings in Lambert Eaton Myasthenia syndrome?
- low or borderline CMAP amplitudes 2. increment in CMAP after exercise 3. decrement with slow repetitive stim 4. increment after fast repetitive stim.
which muscle fibers have slow ATPase activity, large oxidative capacity are red, small, and have lots of mitochondria?
Type I
Which muscle fibers have fast ATPase activity, high glycolytic capacity, moderate oxidative capcity, contract quickly, are red and large in diameter?
Type IIa- fast oxidative-glycolitic
Which muscle fibers have fast ATPase activity, high glycolytic capacity, low oxidative capacity, contract quickly, are pale, and large in diameter.
Type IIb-fast glycolitic
how long do symptoms have to exist before CIDP is diagnosed?
8 weeks
time frame after axonal lesion that NCV shows conduction block
7-10 days. After this time frame conduction block cannot be detected.
what are the nerve roots of the brachial plexus?
C5-T1
which two nerves branch directly off of brachial plexus roots, what roots do they arise from, and what muscles do they innevate?
Dorsal scapular nerve (C4 and C5 -rhomboids and levator scapulae), and long thoracic nerve (C5-C7-, serratus anterior).
which brachial plexus roots give rise to the upper trunk?
C5 and C6
Which nerves branch off of the upper brachial plexus trunk, and which muscles do they innervat?
- Suprascapular- supraspinatus and infraspinatus
- nerve to subclavius- subclavius duh
which nerve roots give rise to the middle brachial plexus trunk?
C7
Which nerve roots give rise to the lower brachial plexus trunk?
C8/T1
which brachial plexus trunks give rise to the lateral cord?
upper and middle
What disease manifests of polyneuropathy, autonomaic features, onset in the 3rd or 4th decade, and AD inheritance? what protein is involved?
Familial amyloid polyneuropathy type 1 (FAP type 1).
transtheretin.
what disease manifests as onset of carpal tunel and slowly progressive polyneuropathy manifesting in the 4th or 5th decase with an AD inheritance pattern?
Familial amyloid polyneuropathy type 2 (FAP2).
what nerve does the lateral cord give rise to and what muscle(s) do(es) it inervate?
lateral pectoral nerve–>pec major
what two nerves does the lateral cord end in?
Median and musculocutaneous.
which brachial plexus trunks contribute to the posterior cord?
Upper, middle, and lower.
what 3 nerves arise from the posterior cord, what root fibers do they carry, and what muscles do they innervate?
- upper subscapular n., C7 and C8, subscapularis 2. lower subscapular nerve, C5 and C6, Teres major 3. thoracodorsal n., C6,7,8, latissimus dorsi.
what two nerves does the posterior cord end in?
axillary and radial
what brachial plexus trunk gives rise to the medial cord?
lower
what 3 nerves does the medial cord give rise to, what root fibers do they carry, and what do they innervate?
- medial pectoral nerve, c C8, T1, pec minor 2. medial brachial cutaneous nerve, sensation to medial arm 3. medial antebrachial cutaneous nerve, sensation to medial forearm.
what nerve does the medial cord end in?
Ulnar nerve- note, it contributes fibers to the median nerve before continuing as Ulnar nerve.
what are the demyelinating CMTs?
CMT1 , CMT3 and CMTX
what are the symptoms of CMT1A?
onset in the 1st two decades, progressive weakness, muscle atrophy, mild sensory loss, hammar toes and pes cavus foot.
What is the gene defect in CMT1A
duplication of PMP22 on Chr 17
What are the symptoms of CMT1B?
similar to CMT1A but more severe.
what gene is involved in CMT1B
myelin protien0 gene
What is the inheritance of CMTX?
X-linked so males are more severely affected.
what gene is involved in CMTX?
Connexin 32.
What is the inheritance of CMT1?
AD
What type of CMT is axonal?
CMT2
Which CMT commonly causes otpic atrophy
CMT2A2
What CMT commonly causes foot ulcerations?
CMT2B
What CMTcauses vocal cord paralysis, intercostal and diaphragmatic weakness?
CMT2C
In which CMT is hand weakness common?
CMT2D
what is the inheritence of CMT2?
AD
What CMT has a severe presentation in infancy?
CMT3
What disease is characterized by focal mononeuropathies caused by compression, what is the gene defect, and what is the inheritence?
Hereditary neuropathy with laiability to pressrue palsies, AD, deletion of PMP22.
what is the most common nerve affected in HNPP?
Peronial followed by Ulnar.
what are the 4 main motions of muscles innervated by the median nerve?
- wrist flexion and abduction 2. forearm pronation 3. finger flexion digits 2 and 3. 4. thumb flexion, opposition
what is the sensory innervation of the median nerve?
shown in green

what are the 3 main motions of muscles innervated by the Radial Nerve?
- extension of all joints below the shoulder 2. forearm supination 3. thumb abduction
what is the sensory innervation of the radial nerve?
fibers from which roots are carreid by the radial nerve?
shown in pink
C5-C8

what are the 4 main motions of muscles innervated by the Ulnar nerve
- finger adduction and abduction 2. THumb adduction 3. flextion of digits 4 and 5 4. wrist flexion and adduction
what is the main sensory input of the Ulnar nerve?

what is the main motion of muscles innervated by the axillary nerve? Fibers from what nerve roots are carried by the axillary nerve?
arm abduction beyond 1st 15 degrees. C5 and 6
what is the main sensory innervation of the axillary nerve?
lateral upper arm.
what is the sensory innervation of the musculocutaneous nerve.
radial aspect of forearm.
what disease causes orange tonsils and neuropathy?
Tangier’s disease
what anti-bodies are involved in acute motor and sensory axonal neuropathy (AMSAN)?
GM1, GM1b, GD1a
what muscles are responsible for finger abduction?
dorsal interossei
mneumonic is DAB
what muscles are responsible for finger adduction?
Palmer interossei
mneumonic is PAD
what neuropathy causes the benedictine sign when you ask the patient to make a fist?
median at the elbow or wrist
what neuropathy causes claw hand when you ask the patient to make a fist?
Ulnar neuropathy at the wrist
what is wartenberg’s sign? What causes it?
5th finger abduction at rest. Due to distal ulnar neuropathy
What is Froment’s sign? What causes it?
thumb flexion during forsible thumb adduction. Due to ulnar neuropathy.
what is the location of ulnar neuropathy in bike riders?
Guyon’s canal
what neuropathy causes the “ok” sign - ie weakness in pinching the thumb and forefinger together?
antior interosseous neuropathy, which is a branch of the median nerve.
what antibody is involved in Miller Fisher Syndrome?
GQ1b
what antibody is involved in acute sensory neuronopathy?
GD1b
what antibody is associated with multifocal motor neuropathy with conduction block?
GM1
what is the nerve injury in saturday night palsy?
radial nerve proxiam to the spiral groove
what syndrome consists of corneal dystrophy, multiple cranial neuropathies, and peripheral sensorimotor neuropathy?
familial amyloid polyneuropathy type 4
what is the genetic abnormality in hereditary neuropathy with liability to pressure palsies?
deletion of PMP22
what is the gene abnromality in CMT1A?
duplication of PMP22
What gene is mutated in X-linked CMT?
Connexin 32
what is the antibody in demyelinating neuropahty with monoclonal gammopathy?
Anti-MAG
what syndrome consists of painful sensory polyneuropathy, autonomic dysfunction, cardiac and renal disease with a family history?
Familial amyloid polyneuropathy Type 1.
what disorder consists of painful episodes in the hands and feet, scrotal angiokeratoma? what is the enzyme defect?
Fabry’s disease, alpha-galactosidase A
What is the mode of inheritence of Fabry’s disease?
X-linked
what peroxisomal disorder includes retinitis pigmentosa and neuropathy? What substance builds up?
Refsum disease. Phytanic acid.
what disease includes retinitis pigmentosa, neuropathy, ataxia, low VLDL, and acanthocytes on peripheral smear? what is the inheritance?
abetalipoproteinemia. AR
what disorder causes attacks of flaccid paralysis with reduced reflexes, triggered by exercise, large meals, and stress? What is the inheritence?
hypokalemic periodic paralysis. AD
what disorder causes attacks of flaccid paralysis triggered by resting after exercise and fasting?
hyperkalemic periodic paralysis.
what gene involved in hypokalemic periodic paralysis Type 1?
CACN1A3
What gene is involved in hypokalemic periodic paralysis type 2?
SCN4A
what gene is involved in hyperkalemic periodic paralysis?
SCN4A
what medication can be helpful in hypokalemic periodic paralysis?
carbonic anhydrase inhibitors
what are 4 treatments for hyperkalemic periodic paralysis?
Low-K, high carbohydrate diet
avoid fasting, cold and strenuous activity
Mexiletine for myotonia
Carbonic anhydrase inhibitors or thiazide diuretics
what is the pattern of weakness in corticosteroid induced myopathy? What fiber types are atrophied?
Proximal, Type II fibers.
what disorder presents has hypotonia and weakness at birth or early childhod, with ptosis and ocular palsies, facial, laryngeal and neck muscle weakness with central nucleation of muscle fibers.
centronuclear (aka myotubular) myopathy
what is the mode of inheritence of centronuclear myopathy?
AD, AR or X-linked
what is the mechanism of action of botulism toxin?
inhibits presynaptic neurotransmitter vessicle release.
what disorder presents with proximal muscle weakness and myotonia, is sometimes assciated with cataracts and cardiac problems?
Dystrophic Myotonia Type 2
what is the genetic abnormality in Dystrophic myotonia type 2?
CCTG repeat expansion in an intron of the zinc finger protein 9 gene.
what disorder is seen in floppy babies with abnormal brain gyral patterns, frontal white matter changes, and has reduced alpha-dystroglycan?
Fukuyama type congenital muscular dystrophy
what disorder presents in a floppy baby with severe trunk and limb weakness with facial sparing and has reduced Laminin-alpha-2
merosen deficiency
what disorder presents in adolescence, predominanty affects face and shoulders, as well as causes foot drop and beevor’s sign?
What gene and inheritance?
FSHD
D4Z4 repeats on Chr 4, AD
what is the mode of inheritance of oculopharyngeal muscular dystrophy?
AD
what disorder is characterized by adult onset of ptosis, facial weakness, frontal balding, infertility, atrophy of masseters and temporalis and upper arm extensors?
dystrophic myotonia type 1
what is the mode of inheritence of myotonic dystrophy type 1?
AD
what disorder presents as exercise induced weakness, muscle cramps and contractures with electrical silence in the contracted muscle?
McArdle’s disease
what enzyme is deficient in McArdle’s disease?
myophosphorylase
what are the main differences between myotonia congenita and paramyotonia congenita?
in paramyotonia congenita there is no “warm up” phenomena and symptoms worsen with exercise.
myotonia congenita = chloride channel
paramyotonia congenita = SCN4A
what is the mechanism of action of pyridostigmine?
inhibition of acetylcholine esterase
what disorder has prominent proximal weakness, puts patient’s at risk for malignant hyperthermia and is due to a mutation in the RYR1 gene.
Central Core disease.
what is the inheritence of central core disease
AD
what is the main difference between central core disease and mini core or mutli core disease?
in central core disease the mitochondiral sparse cores run the whole length of the muscle fiber.
what antibody is present in 50% of patients with autonomic ganglionopathy?
anti-ganglionic nicotinic AchR
What inherited myopathy presents in early adulthood with predmoinant weakness in the anterior tibial muscules? What gene is involved?
Nonaka myopahty, GNE
What inherited myopathy presents in late adulthood predominanty with weakness and atrophy in the hands?
Welander muscular dystrophy
what inherited myopathy presents in late adulthood predominantly with foot and wrist drop?
Markesbery-Griggs- one of the myofibrillary myopathies
what inherited myopathy presents in adulthood with atrophy in the distal posterior compartment of the legs? What gene is involved?
Miyoshi myopathy. Dyferlin
what receptor in the heart does Ach bind to, reducing heart rate?
M2 AchR
What receptors does Ach bind to in autonomic ganglia to decrease presynaptic release of norepinephrine?
M1
What receptors does Ach bind to in the salivary glands to increase salivation?
M3
What antiboy’s are often positive in dermatomyositis and polymyositis?
anti-Jo
what immune suppressive should be avoided in dermatomysoitis if there is interstitial lung disease?
Methotrexate
what disorder presents with autonomic dysfucntion and pathologically has alpha-syneuclein + lewy bodies in the autonomic nervous system?
Pure autonomic failure.
what disorder presents in late adulthood with weakness and atrophy in the wrist and finger flexors, quads and AT muscle, and has pathology showing endomysial inflammation, atrophic fibers, and rimmed vacuoles?
inclusion body myositis
What is the age of onset of Nemalin myopathy?
ranges from neonatal to adult onset
what are the features of adult onset nemalin myopathy?
proximal weakness, cardiomyopathy, respiratory compromise.
what is the mode of inheritence of Nemaline myopathy?
AD or AR
What type of glucogenosis is acid maltase deficiency?
Type II
what is the most common congenital myasthenic syndrome? what is a subtype of this syndrome?
congenital AchR deficiency
congenital myasthenia with episodic apnea
what muscular dystrophy presents with shoulder girdle weakness, contractures and the elbows, ankles and neck, and cardiac conduction abnormalities?
Emery Dreyfus musclular dystrophy
what is the inheritence of Emery Dreyfus muscular dystrophy?
X-linked
what muscular dystrophy presents with neonatal weakness, contracutres and distal hyperlaxity and protrusion of the calcanei? What collagen is affacted?
Ullrich’s congenital muscular dystrophy. Collagen VI
which type of myotonia congenita is AD, has earlier onset, and has a milder phenotype?
Thomson’s disease
which type of myotonia congenita has later onset, is AR and has more severe phenotype?
Becker’s disease
What gene is involved in myotonia congenita?
CLCN1
what is the treatment of choice of myotonia congenita?
Mexiletine
what are the pathologic changes in critical illness myopathy?
loss of thick myosin filaments and type II atrophy
what myopathy presents with weakness, contractures at elbow and ankle, hyperextensible interphalangeal joints and has AD inheritence? type of collagen is affected?
Bethlem myopathy, Collagen VI
what are the features of brain pathology in FTD-ALS?
ubiquitin positive, TDP-43-positive, tau negative inclusions.
what is the most common intra-dural extra-medullary spinal tumor?
meningioma
what is the mechanism of action of riluzole?
inhibits glutamate release
what additional labs should be monitored in B12 deficiency?
Homocysteine and methylmalonic acid.
persistent upper motor neuron signs progressing to spastic tetrapareses, loss of layer V motor cortex neurons.
Primary lateral sclerosis
lateral and posterior column demyelination with microvacuolar changes
Primary HIV related myelopathy
chronic progressive myleopathy in equtorial africa, asia, central and south america, and carribean.
tropical spastic paraparesis due to HTLV1
what is the most common mutation causing HSP? What is the inheritance?
SPAST gene (spastin) on Chr 2p22. Autosomal Dominant.
Spinal levels most suceptabel to spinal watershed infarcts.
T4-T8
motor neuron disease that only affects lower motor neurons.
progressive muscular atrophy
meningitis encephalitis and myeloradiculitis is due to what type of virus?
Flavivirus (West Nile)
what is the biochemical defect in adrenomyeloneuropathy? What gene and chromosome, what is inheritence?
inability to oxidize VLCFAs. ABCD1 gene on Xq28, X-linked.
most common intramedullary spinal tumor in children
astrocytoma
most common intramedullary spinal tumor in adults
ependymoma
spinal injury if sensory level is at the nipple line
T4
spinal injury if sensory level is at the base of the neck
C4
spinal injury if sensory level is at the unbilicus
T10
spinal injury if sensory level is at the groin
L1
spinal injury if sensory loss at the anus
S5
what level is the injury if superficial abdominal reflexes are spared
above T6
conditions associated with atlantoaxial dislocation
down’s syndrome
RA
Klippel-Feil (decreased # of cervical vertibrae)
Morquio syndrome (aplastic odontoid process)
what are the most common metastatic cancers to the spinal cord?
breast, lung, prostate, kidney
gait ataxia, dysarthria, hearing loss, CSF Xanthochromia and T2 hypOintense ring around brain and spinal cord.
superficial siderosis
saddle distribution numbness, symmetric pain, symmetric LE weakness, bowel and bladder dysfunction.
conus medularis lesion.
asymmetric severe radicular pain and sensory loss, asymmetric weakness and hyprreflexia.
cauda equina syndrome.
weakness starting in proximal muscles, lower motor neuron dysfunction, tremor, face fasciculations, gynocomastia. What is the trinucleotide repeat?
Kennedy’s disease (bulbospinal muscular atrophy), CAG in androgen receptor protein gene on X chromosome.
patient with a history of gastric bypass gets acute myelopathic symptoms after inhaled anesthesia
nitric oxide myelopathy. Associated with B12 deficiency.
most common bug in epidural spinal abscess
S. Aureus
progressive asymmetric wasting of hands and forearms in asian patients.
Hirayama disease
slowly progressive pain and temp loss, distal skin ulcers, charcot joints, mild autonomic dysfunction.
Gene and inheritance.
HSAN1, AD, SPTLC1
Severe sensory loss and areflexia at birth, distal skin ulcers, charcot joints, imparied sweating and bladder dysfunction.
Gene and inheritance
HSAN2, PRWNK1, AR
Familial dysutonomia starting in infancy. Presents with temp, BP fluctuations, GI dysmotility, tonic pupils and orthostatic Hypotension. More common in Aschkenazi Jews.
Gene and inheritance
HSAN3, IKAP, AR
childhood onset insensitivity to pain, self mutilation anhidrosis, MR, risk of hyperthermia.
Gene and inheritance
HSAN 4, trkA/NGF, AR
congenital indifference to pain
HSAN5
what type of neuropathy follows Hep C infection?
vasculitic
at what time in HIV infection can AIDP occur?
at the time of seroconversion
most common peripheral neurpathy in HIV
distal sensory polyneuropathy
first step in mechanism of botulism toxicity
cleavage of botulism in to light and heavy chains
which botulism chain binds to presynaptic membrane for endocytosis?
Heavy
which botulism chain cleaves SNARE and SNAP proteins of the vessicle release complex?
light
in which disorder is there EMG evidence of myotonia without clinical myotonia?
Acid maltase deficiency (glycogenosis Type II)
inability of an axon to transmit an action potential despite being intact, most commonly due to compression.
mechanism and time frame of recovery
neuropraxia
remyelination
6-8 weeks
axon discontinuity without loss of fascicular connective tissue.
mechanism and time frame of recovery
axontemesis
collateral sprouting and regeneration from proximal stump
at least 2-6 months
complete transection of the axon and fascicular connective tissue.
neurontemesis.
what is depicted?

Tamacula, Hereditary neuropathy with liability to pressure palsies
what is depicted?

peripheral nerve onion bulb formation, seen in CMT 1, 3 and 4
what is the 2nd most common gene mutated in HSP?
SPG3A (alastin)
nerve injury in scapular winging with the inferor edge rotated medially
Long thoracic nerve
nerve injury with scapular winging with the inferior edge rotated laterally
dorsal scapular nerve
what nerve injury results in impaired arm adduction, arm medial rotation, and arm extension?
Thoracodorsal nerve injury
what type of disorder is depicted?

congenital muscular dystrophe (fiber size variability and excess connective tissue)
intermittent muscle cramps and weakness. Forearm ischemia test shows elevation in Lactate with no elevation in ammonia.
myoadenylate deaminase deficiency
what disorder is depicted?

dermatomyositis
ptosis and facial weakness without ophthalmoplegia
dystrophic myotonia type 1
small amplitude monophasic potentials 20-40 Hz that sound like hissing or the ocean/seashell
endplate noise
brief, irregular discharges with initial negative deflection and crackling or buzzing sound on EMG
Endplate spikes
what disorders are positive sharp waves seen in?
Denervating
in what disorders is there Type I muscle fiber atrophy
myotonic dystrophy, centronuclear myopathy. congenital fiber type disporportion
which myopathies are associated with arrhythmias?
Kearn-Sayer
Emery Dryfus
polymyositis
middle aged man with slowly progressive asymmetric hand weakness and weakness out of porportion of atrophy.
multifocal motor neuronopathy
what type of neuropathy is multifocal motor neuronopathy
demyelinating
what is the treatment for multifocal motor neuronopathy
IVIG or cyclophosphamide (steroids don’t work)
most frequent cranial nerve affected in Sarcoidosis
facial nerve
most common cranial nerve affected in diptheria
glossopharyngeal
what muscles does the obturator nerve innerveate? fibers from what nerve roots run in the obturator nerve?
obterator externus and leg adductors (all have “adductor” in the name)
L2, 3
what is the action of Iliopsoas? What nerve innervates it? What is the primary nerve root?
Flexes leg at the hip.
Femoral
L3
What 4 muscles comprise the quadriceps?
What is their action
what nerve innervates them?
What is the primary nerve root(s)?
Rectus femoris, vastus medialis, intermedius and lateralus.
Extends leg at knee
Femoral
L3/4
what are the 3 main muscles of the Hamstrings?
What nerve innervates them?
What is the action?
What is primary nerve root?
semimemranosus, semitendinosus, biceps femoris
Sciatic
knee flexion, hip extension, medial thigh rotation
S1
What are the 5 main muscles innervated by the tibial nerve?
- Soleus
- Popliteus
- Tibialis posteiror
- Flexor digitorum longus-
- flexor hallucis longus
what is the main action of the tibialis posterior muscle what is the nerve root?
plantar flexion and foot inversion
L4/5
what are the main muscles innervated by the superficial peroneal nerve? What are their actions? What nerve root?
peroneus longus and brevis. Plantarfelxion and eversion. S5/S1
what are the main muscles innervated by the deep peroneal nerve, what are their actions, what are the nerve roots?
Tibialis Anterior- dorsiflexion, L4/5
Extensor digitorum longus- toe extension, L5/S1
Extensor digitorum brevis- extends toes, L5/S1
Extensor hallucis longus- extends great toe, L5/S1
Loss of sensation with femoral nerve injury

loss of sensation with obturator nerve injury

loss of sensation with sciatic nerve injury

loss of sensation with tibial nerver injury

loss of sensation with superficial peroneal nerve injury

loss of sensation with deep peroneal nerve injury

what congenital myasthenic syndrome includes slow pupillary light reflex? What is the EMG finding?
congenital endplate acetylcholinesterase deficiency. repetitive compound action potentials.