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1621 Cards in this Set
- Front
- Back
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Where is the cell body of a motor neuon located?
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ventral horn of spinal cord
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How many axons does a sensory neuron have?
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2 (1 proximal projection and 1 distal projection)
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Where is the cell body of a sensory neuron located?
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dorsal root ganglion
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What cell myelinates?
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Schwann
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Each spinal nerve branches into what two rami?
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dorsal and ventral
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What is the innervation ratio?
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The amount of muscle fibers belong to an axon
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What has a higher innervation ratio nerves of gross movement or fine movement?
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gross movement
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What is a myotome?
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group of muscles innervated by 1 spinal segement
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What is the endoneurium?
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connective tissue surrounding each axon and its myelin sheath
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What is the perineurium?
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connective tissue surrounding bundles or fascicles of myelinated and unmyelinated nerve fibers
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What is the epineurium?
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connective tissue surrounding the entire nerve holding the fascicles together
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What nerve covering is the strongest?
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Perineurium
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What are the 6 components of the motor unit, starting proximally?
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anterior horn cell
motor nerve axons peripheral nerve neuromuscular junction muscle fibers |
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What type of motor neurons does EMG evaluate?
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alpha motor neurons
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What is the Henneman Size Principle?
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smaller alpha motor neurons have lower excitation threshold and are recruited first
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What are the three tyes of motor neurons, and what does each innervate?
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alpha - extrafusal skeletal muscle
gamma - intrafusal fibers - muscle spindle beta -intrafusal and extrafusal fibers |
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What are 4 characteristics of Type I fibers, in terms of size, diameter, innervation ratio, and twitch speed?
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smaller - cell body
thinner - axon diameter lower - innervation ratio slower - twitch muscle fibers |
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What are 4 characteristics of Type II fibers, in terms of size, diameter, innervation ratio, and twitch speed?
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larger - cell bodies
thicker - axon diameter higher - innervation ratio faster - twitch muscle fibers |
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What type of fibers does EMG evaluate?
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Ia - large, myelinated fibers
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What is the velocity range of type Ia?
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50-120 m/sec
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What are Ib fibers?
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sensory: golgi tendon organ -touch and pressure
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What are the largest fibers?
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Ia - 10-20 um
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What type of sensory innervation is carried by Ia or A-alpha fibers?
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sensory muscle spindle
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What type of fibers carry pain and temperature signals?
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IV or C-fibers
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What type of fibers carry pre and post-ganglionic motor autonomic signals?
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IV or B-fibers
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What are the smallest fibers?
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IV or C-fibers - pain and temperature
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What are the slowest fibers?
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IV or C-fibers
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What is the normal resting membrane potential?
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-70 to -90 mV
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Leak channel allow what two ions to move passively in and out of cells?
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Na+ and K+
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What is the normal polarity of the cell interior?
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negative
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What is the active ration of transfer of Na+ and K+ by the Na-K ATP Dependant pumps?
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3 Na+ exported and
2 K+ imported |
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What is the most important event in generating an action potential?
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Increased Na+ permeability and Na+ rushes into the cell toward an equilibrium
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In what direction does an action potential travel?
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both directions
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What are two factors that cause decrease in amplitude?
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increase in temporal dispersion
phase cancellation |
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How long do Na+ channels remain open?
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25ms
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What happens to the following parameters of waveform appearance due to a decrease in temperature?
latency amplitude duration conduction velocity |
latency - prolonged
amplitude - increased duration - increased conduction velocity - decreased |
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What is the process of propagating a current from one node to another?
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saltatory conduction
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Repolarization is dependant on what 2 channel actions?
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Na+ channel inactivation
K+ channel activation |
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What separates the motor axon from the individual motor fibers?
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primary and seconday synaptic clefts
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How many AcH molecules are in each quanta?
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5,000-10,000
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How many quanta are stored in the following compartments?
Main Mobilized store Immediate store |
main - 300,000
mobilized store - 10,000 immediated sotre -1,000 |
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What process restores the waveform (resting membrane potential) to is baseline?
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K+ leak channels or potassium conductance
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How wide is the synaptic cleft?
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200-500 angstroms
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What enzyme is contained in the synaptic cleft and what does it do?
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acetylcholinesterase
it breaks AcH into acetate and choline |
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How much larger is the postsynaptic region than the the synaptic cleft? Why?
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10x - due to convolutions
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How many AcH molecules are required for a post-synaptic AcH receptor to become activated?
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2
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What is a minature endplate potential?
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Release of 1 quanta every 5 seconds during periods of inactivation
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What floods the nerve terminal during activation?
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Ca++
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What cascade of events leads to the generation of a motor unit action potential?
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Ca++ floods the nerve terminal leading to release of multiple quanta into the synaptic cleft, increasing the number of MEPPs that summate to form an endplate potential and generates a motor unit action potential
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How much higher in amplitude is the endplate potential than that required to initiate a MUAP and what is this called?
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4x; safety factor
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On what 2 factors does the safety factor depend?
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quantal content
quantal response |
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What is the quantal content?
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number of ACh quanta released with each nerve depolarization
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What is the quantal response?
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the ability of the ACh receptors to respond to the ACH molecules that are released
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What is the basic unit of a muscle's myofibril?
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sarcomere
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What are length parameter of a sarcomere?
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from Z-line to Z-line
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What shape is a sarcomere?
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cylindrical
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What are the 3 types of muscle fibers innervated by alpha motor neurons?
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Type I
Type II-A Type II-B |
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Type I is also known as?
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Slow twitch oxidative
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Type II-A is also know as?
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Fast twitch oxidative-glycolytic
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Type II-B is also know as?
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Fast twitch glycolytic
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What is the recruitment (early or late) of Type I, II-A and II-B?
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I-early
II-A-late II-B - late |
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Describe the fatigueability of Type I, II-A and II-B.
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Type I - highly resistent
II-A - resistent II-B - sensitive |
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What are the movements (fine or gross) of Type I, II-A, and II-B?
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I - fine
II-A gross II-B gross |
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What is the innervation ratio of I, II-A, and II-B?
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I - small
II-A large II-B large |
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What is the amplitude/duration of type I, II-A, and II-B?
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Type I - small
II-A large II-B large |
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What is the O2 capacity of type I, II-A, and II-B?
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Type I - aerobic
II-A anaerobic II-B anaerobic |
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What is the color of type I, II-A and II-B?
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I - dark
II-A - dark II-B - dark |
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Through what system does the muscle fiber depolarization penetrate deeper into the muscle fiber?
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T-tubule system
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How fast does depolarization spread on the muscle fiber?
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3-5 meters per second
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Depolarization of the muscle fiber causes what to be released and from where?
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Ca++ from the sarcoplasmic reticulum
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What binds to the tropin-tropomyosin complex?
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Ca++
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How does the muscle shorten?
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By actin and myosin filaments sliding over each other.
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What powers the myosin heads to bind with the Ca++- exposed actin active sites?
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ATP
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What is the size (large or small) of Type I, II-A, and II-B muscle fibers?
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Type I - small
II-A large II-B large |
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What effort is required to activate Type I, IIA and IIB fibers?
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I mild
IIA intermediate IIB high |
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What is the firing frequency of Type I, IIA and IIB?
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I - slow and prolonged
IIA - fast and unsustained IIB - fast and unsustained |
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What is the cause of rigor mortis?
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Lack of ATP results in the actin and myosin filaments being permanently joined
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How is muscle fiber relaxation attained?
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Powered by ATP, Ca++ is pumped back into the sarcoplasmic reticulum, allowing tropomyosin to block actin's active sites, thus allowing actin and myosin to slide away from each other.
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Demyelination increases or decreases membrane capacitance? and what does this do to saltatory conduction?
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increases capacitance, thus hindering saltatory conduction
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What is a conduction block?
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failure of a MUAP to propagate past an area of dymelination
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What percentage drop in CMAP amplitude can be seen in conduction block between proximal and distal stimulation across the area of injury?
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50%
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What is a common cause of conduction block?
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compression
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What cells produce myelin:
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Schwann cells
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How is new myelin different and than normal myelin?
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new myelin is thinner, with shorter internodal distances
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What are the two types of axonal injury?
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axonal degeneration and Wallerian degeneration
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What is the direction of axonal degeneration?
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distal to proximal
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What is the direction of Wallerian degeneration
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site of nerve lesion to distal
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How long does it take for degeneration to take place in motor and sensory nerves during Wallerian degeneration?
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motor - 7 days
sensory - 11 days |
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What type of waveforms and amplitudes result from collateral sprouting?
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polyphasic with increased amplitudes
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What is the rate of axonal regrowth per day in mm) and per month ( in inches)?
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1mm/day
1 inch (35mm)/month |
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If connective tissue is not intact to guide proper nerve regrowth, what is the result?
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neuroma
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What are the two systems of nerve injury classification?
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Seddon and Sunderland
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What are the 3 types of nerve injury using the Seddon system?
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Neurapraxia, Axonotmesis, and Neurotmesis
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What is the etiology of neurapraxia?
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nerve compression
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What is the etiology of axonotmesis?
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nerve crush injury
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What is the etiology of neurotmesis?
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nerve transection injury
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What is the axon injury in neurapraxia, intact or not? What is the myelin injury? What conduction disorder happens?
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axon is intact
local myelin injury conduction block |
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What is the axon injury in axonotmesis in terms of the axon and conduction?
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axonal interruption
conduction failure |
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What are the injuries in neurotmesis in terms of the axon, connective tissue, and conduction?
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axonal interuption
connective tissue disruption conduction failure |
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What does the NCS show across the injury in neuraprxia/distal to the injury?
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abnormal/normal distal
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What does the NCS show in axonotmesis?
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conduction is like neurapraxia for 4-5 days until Wallerian degeneration occurs
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What does NCS show in neurotmesis in terms of conduction?
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conduction initially resembles axonotmesis, but does not demonstrate recovery
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What does the EMG show in neurapraxia, axonotmesis, and neurotmesis?
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neurapraxia: normal/decreased recruitment
axonotmesis: abnormal activity neurotmesis: abnormal |
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What is a type 1 injury?
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conduction block (neurapraxia)
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What is a type 2 injury?
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axonal injury (axonotmesis)
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What is a type 3 injury?
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type 2 + endoneurim injury
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What is a type 4 injury?
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type 3 + perineurium injury
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What is a type 5 injury?
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type 4 + epineurium (neurotmesis)
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What is the formula for Ohm' s Law?
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Current (amps) = Voltage/Resistence
I-V/R or V=IxR |
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What is the CMAP?
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a summation of electrical activity generated by muscle fibers. It is an indirect representation of electrical activity generated by a motor nerve
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What do needle electrodes record?
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muscle or nerve action potentials
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What two characteristics cannot be assessed if needle electrodes are used in NCS?
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amplitude and conduction velocity
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What is the gauge and how long (in mm2) is a monopolar needle?
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22-30 G
0.15-0.2 mm2 |
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What is the direction of monopolar recording?
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omnidirectional
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Monopolar needles record more of what wave in general?
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PSWs
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How much larger of a recording area does a monopolar needle cover than a concentric needle?
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2x
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What is the standard needle?
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concentric
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What is the gauge of a concentric needle?
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24-26G
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What is a main disadvantage of monopolar needle?
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needs separate needle or surface reference
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What needle is used for quantitative EMG?
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concentric
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What is the direction of a concentric needle?
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unidirectional
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What MUAP amplitudes are larger, those of a monopolar or concentric needle?
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monopolar
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What is the active electrode in a concentric needle?
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bare inner wire
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What is the reference in a concentric needle?
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the outer 24-26G needle
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What has less interference, monopolar or concentric needle?
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concentric
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What needle is best for isolating a MUAP?
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bipolar concentric
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What is more painful concentric or monpolar?
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concentric
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What is the cheapest needle?
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monopolar
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What is the structure of a bipolar concentric needle?
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active and reference wires within the lumen of the needle
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What needle is used to evaluate individual muscle fibers?
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single fiber needle
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What needle is used in neuromuscular junction disorders?
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single fiber
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What 3 parameters does a single fiber needle best assess?
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fiber type density
jitter fiber blocking |
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Where is a ground electrode placed?
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between the recording and stimulating electrodes
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What are the two poles on a stimulating electrode device?
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anode
cathode |
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What does a stimulation from the cathode attract?
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attracts positive charges from the axon
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What type of charge does the anode generate?
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positive
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What type of charge does the cathode generate?
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negative
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What does a stimulation from the anode attract?
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negative charges from the axon
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What is an anodal block?
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hyperpolarizing a nerve by reversing the stimulators anode and cathode
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No further increase in an evoked potential will occur with added stimulus is called what?
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maximal stimulus
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What 2 parameters can submaximal stimulus affect? and how?
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amplitude - falsely lowered latency- falsely prolonged
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A falsely lowered amplitude and falsely prolonged latency can lead to what false diagnosis?
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axonopathy or conduction block
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A supramaximal stimulus s what % above a maximal stim?
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20%
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During what study is a supramaximal stimulus used?
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NCSs
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What phenomenon occurs with supramaximal stimulus?
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volume conduction
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What is volume conduction?
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When the stimulus current spreads through tissue surrounding the nerve, such as skin, muscles, fluid, etc.
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What is the result of volume condution using the parameters of conduction times, waveform, latency, amplitude
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conduction time: decreased
waveform: altered amplitude: unchanged |
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What is the standard stimulus duration?
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0.1 ms
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What is the typical initial supramaximal stimulation duration using a monopolar needle?
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0.5ms
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What is the signal:noise ratio?
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Signal amplitude x square root of number of averages performed/noise amplitudue
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What is stim artifact? When does it occur?
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current spread to the electrode; seen at the time of the stim
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What is the common mode rejection ratio (CMRR)? How is it measured and what is a typical setting?
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selectively amplifying different signal and rejecting common signals. decibels; >90dB
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The larger the CMRR the more/less efficient the amplifier?
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more efficient
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In what device is the differential amplifier located?
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preamplifier
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What electronic devices comprises the filters?
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resistors and capicitors
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What are filter settings for
sensory NCS motor NCS EMG? |
sensory NCS: 20Hz-10kHz
motor NCS: 2Hz-10kHz EMG: 20Hz - 10kHz |
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What parameter is affected by lowering the high frequency filter or raising the low frequency filter?
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waveform morphology
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What is the horizontal axis?
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sweep speed
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What is the vertical axis?
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sensitivity
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What is the unit of measure for sweep speed?
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milliseconds
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What is the unit of measure for sensitivity?
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millivolts (mv) or microvolts (uv)
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What is another word for sensitivity?
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gain
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What is the ratio of output to input called?
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gain
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What is the typical sweep speed setting for sensory, motor, and EMG?
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sensory: 5ms
motor: 2ms EMG: 10ms |
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What is the typical sensitivity setting for sensory, motor, and EMG?
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sensory: 10uV
motor: 5mV EMG: 100uV |
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What is the sensitivity setting for recruitment pattern analysis?
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1mV
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In NCS, the recorded potentials represent a compilation of what type of waves?
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sinusoidal waves
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What is the unit of measure for cycles/sec?
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Hz
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Onset latency represents the time required for electrical stimulus to initiate an evoked potential in what type of fiber in sensory NCS?
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fastest fibers
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True or False: For motor NCS, conduction along the fastest fibers does not correlate with onset latency.
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True
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Why does conduction along the fastest motor fibers not correlate with onset latency in motor NCS?
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the neuromuscular junction cushions the latency
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What is peak latency?
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Measured at the peak of the waveform, it represents the latency along the majority of hte axons.
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Both peak and onset latency are primarily dependant of what?
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myelination of a nerve
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What is latency of activation in a motor study? How long is it?
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time between initiation of impluse and the beginning of saltatory conduction. 0.1ms or less
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What type of conduction is referred to during motor studies?
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saltatory conduction
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Is there synaptic transmission in sensory studies?
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No, due to a lack of neuromuscular junciton.
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What is the duration of synaptic transmission in motor studies?
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0.2-1.0ms
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What is the horizontal axis?
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sweep speed
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What is the vertical axis?
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sensitivity
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What is the unit of measure for sweep speed?
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milliseconds
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What is the unit of measure for sensitivity?
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millivolts (mv) or microvolts (uv)
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What is another word for sensitivity?
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gain
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What is recorded at the initial deflection from baseline?
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onset latency
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Initiation of conduction along the majority of the axons is called what?
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peak latency
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What is the primary determinant of conduction velocity?
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integrity of myelin sheath
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What is a normal CV in upper limbs/lower limbs
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upper: >50m/s
lower: >40m/s |
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What are two factors that can change CV?
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age
temperature |
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What is the CV for a newborn compared to that of an adult in percentage?
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50%
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At what age range is a child's CV equal to that of an adult?
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3-5 years old
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What is the rate of decrease per decade in CV after the fifth decade?
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1-2 m/s per decade
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What is the normal temperature for upper/lower limb CV?
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upper: 32 C
lower: 30 C |
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What is the decrease in CV per 1 cc drop?
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2.4 m/s
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The number fibers activated and their synchronicity of firing is called what?
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amplitude
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On what two factors is duration dependant?
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summation
rate of firing of numerous axons |
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At what location of stimulation is temporal dispersion seen best? (distal or proximal)
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proximal stim
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A drop in amplitude and an increase in duration occurs when comparing a proximal to distal stimulation in what nerve action potential?
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SNAP
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Why does a drop in amplitude and increase in duration occur with a SNAP when comparing proximal to distal stimulation?
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Because of SNAP's short duration
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What is considered a normal drop (in %) of a SNAP when comparing proximal to distal amplitudes?
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50% less in a proximal SNAP
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What is considered a normal drop (in %) of a CMAP when comparing proximal to distal amplitudes?
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15% less in proximal CMAP
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Where is DRG located?
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In the intervertebral foramen
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What does the DRG contain?
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The sensory cell body
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Preservation of the SNAP occurs when a lesion occurs (proximal/distal) to the DRG?
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proximal (i.e. sensory nerve root or spinal cord)
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What is more sensitive, a SNAP or CMAP in the detection of an incomplete nerve injury?
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SNAP
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Amplitude of antidromic studies are larger/smaller than orthodromic studies and why?
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larger/nerve is more superficial distally
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How far apart should the active and reference electrodes be?
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at least 4 cm
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How are the following parameters affected by less than 4cm separation between active and reference electrodes in sensory NCS?
peak latency amplitude duration rise time |
all decreased
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CMAPs are also known as
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M wave
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Can a CMAP distinguish between a pre- and post-ganglionic injury?
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No, because the cell body is located in the spinal cord. (the sensory cell body is located in the foramen)
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If a lesion is proximal to the DRG or affecting a purely motor nerve, what is normalcy of SNAP and CMAP?
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SNAP - normal
CMAP - abnormal |
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A normal SNAP and abnormal CMAP can be seen in what two lesion locations?
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lesion proximal to foramen
purely motor lesion |
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What is the initial deflection in a CMAP?
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negative
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An initial positivity in a CMAP may be due to what 3 factors?
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electrode placement away from motor point
volume conduction anomalous innervations |
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What 3 structures does a CMAP evaluate
|
Motor nerve fibers
NMJ muscle fibers |
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What latency is measured in a CMAP?
|
onset latency
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How is amplitude measured in a CMAP?
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baseline to peak
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How is amplitude measured in a SNAP
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peak to peak
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What are the two pertinent latencies in a SNAP?
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peak or onset latency
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What is the anatomy examined in a SNAP?
|
sensory nerve fibers
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What is a H-reflex?
|
Electrically-evoked NCS late response analogue to a monosynaptic reflex
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With what level stim and duration is an H-reflex evoked?
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submaximal; long duration (0.5-1.0 milliseconds)
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What nerve fibers are activated in a H-reflex? and what is the direction? Is it sensory or motor?
|
IA fibers/orthodromic sensory to the spinal cord; then a orthodromic motor response back to the recording electrode
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|
|
How can an H-waveform be potentiated?
|
agonist muscle contraction
|
|
|
In what two ways can a H-waveform be abolished?
|
antagonist muscle contraction
increased stimulation causing collision blocking |
|
|
How do successive stimulations affect H-wave latency and morphology?
|
constant
|
|
|
What is a surrogate for one H-reflex?
|
10 F waves
|
|
|
What conditions can a H-wave response diagnose?
|
S1 radiculopathy; C7 radiculopathy
|
|
|
What nerve is stimulated in H-wave?
|
IA afferent
|
|
|
What wave response is produced when a few motor axons are directly stimulated while evoking a H-wave?
|
M response
|
|
|
What motor neuron is stimulated in the spinal cord while evoking a H-wave?
|
alpha motor neuron
|
|
|
What distance is measured in H-wave testing?
|
medial malleolus to popliteal fossa
|
|
|
Greater than what side to side difference is significant in H-wave testing?
|
>0.5-1.0 ms
|
|
|
Where are the active H-wave stim muscles/nerve/spinal level in upper/lower extremity?
|
upper: flexor carpi radialis/median/C7
lower extremity: soleus/tibial nerve/S1 |
|
|
In what two types of patients can a H-wave always be evoked?
|
normal infants
patients with a corticospinal tract lesion |
|
|
Can a H-wave distinguish between a chronic and an acute lesion?
|
no
|
|
|
What is the F wave?
|
a small late motor response occuring after the CMAP
|
|
|
How is a F-wave produced?
|
short duration supramaximal stimulation
|
|
|
What direction motor response is produced in a F wave?
|
antidromic motor response
|
|
|
What cells are stimulated in a F wave?
|
anterior horn cells in the spinal cord
|
|
|
Is there a synapse in the F-wave?
|
no
|
|
|
What direction is the anterior horn cell response in a F wave?
|
orthodromic motor
|
|
|
What is the nature of an F-wave, purely sensory, purely motor, or mixed?
|
purely motor
|
|
|
What percentage of a CMAP amplitude is the F-wave amplitude?
|
1-5%
|
|
|
Do the configuration and latency of the F-waveform change with each stimulation?
|
Yes, due to activation of different anterior horn cells with each stimulation
|
|
|
In what tow types of pathologies is an F-wave helpful?
|
polyneuropathy
plexopathy |
|
|
In F-wave what side-to-side difference is significant in upper and lower extremities?
|
>2ms in upper extremities
>4ms in lower extremities |
|
|
From what muscles can an F-wave be evoked?
|
any muscle
|
|
|
What fibers does the F-wave evaluate?
|
motor fibers
|
|
|
What waveform is created by collateral sprouting?
|
A (axon) wave
|
|
|
Between what two waves does an A wave occur?
|
between CMAP and F wave at a constant latency
|
|
|
An A wave is created by what direction stimulus along a what type of nerve?
|
antidromic/motor nerve
|
|
|
What is the electrically evoked analogue to the corneal reflex?
|
blink reflex
|
|
|
What nerve is stimulated in a blink reflex?
|
supraorbital branch of the trigeminal nerve
|
|
|
The blink reflex propagates into what two brain structures?
|
pons
lateral medulla |
|
|
The blink reflex eventually propagates what two muscles innervated by what nerve?
|
ipsilateral and contralateral orbicularis oculi via the facial nerve
|
|
|
Where are the reference electrodes placed in the blink reflex?
|
lateral to the lateral canthus
|
|
|
What cranial nerves are involved with the blink reflex
|
CN V and VII
|
|
|
What nerve fibers (CN and nerve) in the blink reflex are involved with the afferent pathway?
|
sensory branches of CN V (trigeminal)
|
|
|
What effernet CN (nerve) are involved with the blink reflex?
|
CN VII (facial nerve)
|
|
|
Through what structure does the RI (early) response go in the blink response?
|
pons
|
|
|
Through what two structures does the R2 (late) response go in the blink reflex?
|
pons and lateral medulla
|
|
|
R1 is affected by lesions in what 3 structures?
|
trigeminal nerve
pons facial nerve |
|
|
R2 is affected by what medication?
|
diazepam
|
|
|
R2 is affected by what 2 neurological conditions?
|
parkinson's disease
lateral medullary syndrome |
|
|
R2 is affected by lesions of what hemisphere in relation to the side being tested?
|
contralateral hemisphere
|
|
|
R2 is affected by what constitutional symptom?
|
consciousness level
|
|
|
What is the normal R1 latency in ms?
|
<13ms
|
|
|
What is the normal R2 ipsilateral latency?
|
<40ms
|
|
|
What is the normal R2 contralateral latency?
|
<41 ms
|
|
|
Where is direct facial nerve stimulation performed?/Where is the response recorded?
|
angle of mandilble/naslis muscle
|
|
|
An aberrant regeneration of axons can occur with facial nerve injuries leading to reinnervation of inappropriate muscles. This may present as lip twitching when closing an eye or crocodile tears when chewing. What is this called?
|
synkinesis (reinnervation of innappropriate muscles)
|
|
|
What conditions cause abnormalities in direct facial nerve study>
|
Bell's palsy, neoplasms, fractures, middle ear infection, DM, mumps, lyme disease
|
|
|
What are treatment interventions for facial nerve injuries>
|
prednisone, massage, or electrical stim
|
|
|
What indicates a poor prognosis in facial nerve study?
|
absence of evoked potential in 7 days.
|
|
|
What is the route of stimulation of structures during SSEP? (peripheral to proximal 7 structures)
|
peripheral nerve
plexus root spinal cord (posterior column) contralateral medial meniscus thalamus somatosensory cortex |
|
|
Through what section of the spinal cord does a SSEP pass?
|
posterior column
|
|
|
What type of stimulation is required for a SSEP?
|
repetitive submaximal
|
|
|
What is the most commonly used UE/LE nerve for SSEP?
|
UE: median nerve
LE: tibial nerve |
|
|
What are 3 common conditions/scenarios for which SSEP is performed?
|
peripheral nerve injuries
MS intra-operative spine surgery |
|
|
In SSEP testing for MS, what is more likely to be abnormal, UEs or LEs?
|
LEs
|
|
|
What is the most common SSEP abnormality?
|
prolonged interpeak latency
|
|
|
What SSEP finding is significant during spinal cord surgery?
|
loss of tibial nerve potentials with preservation of median nerve potentials
|
|
|
What part of the brain is monitored during LE nerve stimulation?
|
fasciculus gracilis
|
|
|
What part of the brain is monitored during UE nerve stimulation?
|
fasciculus cuneatus
|
|
|
Where are the following UE SSEP points?
N9 N11 N13 N20 |
N9 - erb's point
N11 - rootsw N13 - nucleus cuneatus (cervical medullary junction) N20 - cortex |
|
|
Where are the following LE SSEP points?
PF L3 N22 N45 |
PF - popliteal fossa
L3 - third lumbar N22 - T12 and lumbosacral spine N45 - cortical |
|
|
What two qualities of a nerve does SSEP evaluate?
|
vibration and proprioception
|
|
|
What factors affect the SSEP study?
|
sleep
high doses of general anesthetics (halothane, enflurane, and isoflurane) |
|
|
Does nitrous oxide affect SSEPs?
|
No
|
|
|
What three electrical characteristics of a muscle does EMG test?
|
insertional activity
resting activity voluntary recruitment |
|
|
What is insertional activity?
|
muscle depolarization or discharge potentials
|
|
|
Name two etiologies that increase insertional activity.
|
denervation
irritable cell membrane |
|
|
Name 4 etiologies that decrease insertional activity.
|
fat
fibrosis edema electrolyte abnormalities |
|
|
Are endplate potentials monophasic or biphasic/positive or negative?
|
biphasic negative
|
|
|
An EMG needle placed near a NMJ can evoke what two responses?
|
EPP
MEPP |
|
|
What is MEPP activity due to?
|
spontaneous quanta release (100-200 quanta) every 5 seconds
|
|
|
Is MEPP resting activity propogated or non-propagated?
|
non-propagated
|
|
|
Is EPP resting activity propagated or nonpropagated?
|
propagated
|
|
|
Is EPP resting activity due to single or multiple fiber muscle action potential(s)
|
single muscle fiber action potential
|
|
|
What are two hallmark signs of EPP resting activity during EMG?
|
irregularity
negative deflection |
|
|
With what can the negative deflection of EPP resting activity be confused?
|
positive wave
|
|
|
What causes the EPP resting activity spike?
|
increased ACh release
|
|
|
What is the classic sound of MEPP during resting activity?
|
sea shell murmur
|
|
|
What is the classic sound of EPP during EMG resting activity?
|
sputtering fat in a frying pan
|
|
|
What are the two sources of abnormal spontaneous activity?
|
muscle fiber
motor unit |
|
|
If an abnormal motor unit is the source of spontaneous activity, what is its apperance like?
|
MUAP
|
|
|
What is the baseline of a MEPP? regular or irregular?
|
irregular
|
|
|
What are the 5 sources of spontaneous waveform?
|
multiple muscle fibers
single muscle fiber NMJ Motor neuron/axon Terminal axon |
|
|
A muscle fiber source of spontaneous activity can produce what 3 waveforms?
|
fibrillation
positive wave myotonia |
|
|
A multiple muscle fibers source of spontaneous activity creates what kind of waveform?
|
complex repetitive discharge
|
|
|
A terminal axon source of spontaneous activity produces what kind of waveform?
|
end-plate spike
|
|
|
A motor neuron/axon source of spontaneous activity produces what 5 waveforms?
|
fasciculation
myokymia tetany cramp neuromyotonia |
|
|
A NMJ source of spontaneous activity produces what kind of waveform?
|
end-plate noise
|
|
|
What is the hallmark sign of fibrillation potentials?
|
regularity
|
|
|
What is the cause of fibs?
|
uncontrolled ACh release
|
|
|
Where are fibs generated?
|
a muscle fiber
|
|
|
Where are PSW generated?
|
a muscle fiber
|
|
|
What does a PSW represent?
|
action potenial of a single muscle fiber
|
|
|
What is the initial deflection of a PSW and FIB?
|
postivie
|
|
|
What is the rhythm of fibs and psws?
|
regular
|
|
|
What are 5 nerve disorder etiologies of PSWs and FIBs?
|
anterior horn cell disease
radic plexopathy peripheral neuropathy mononeuropathy |
|
|
What are two NMJ disorder etiologies of PSWs and FIBs?
|
myasthenia gravis
botulism |
|
|
What are 5 muscle disorder etilogies of PSWs and FIBs?
|
muscular dystrophy
polymyositis dermatomyositis hyperkalemic periodic paralysis acid maltase deficiency |
|
|
What is the origin of a CRD?
|
principle pacemaker muscle fiber
|
|
|
By what type of transmission does a CRD current travel to other muscle fibers?
|
ephaptic transmission
|
|
|
What is the origin of ephaptic transmission?
|
denervated collateral sprouting
|
|
|
What is the hallmark sign of a CRD?
|
regular interval between and within each discharge
|
|
|
What is the sound of a CRD?
|
motorboat
|
|
|
Is a CRD pre- or post-junctional?
|
post-junctional
|
|
|
What is the initial deflection of a CRD?
|
positive
|
|
|
What are 3 nerve disorder etiologies of CRDs?
|
anterior horn cell disease
chronic radic peripheral neuropathy |
|
|
What are 5 muscle disorder etiologies of CRDs?
|
polymyositis
dermatomyositis muscular dystrophy limb-girdle dystrophy myxedema |
|
|
Can CRDs be a normal variant?
|
yes
|
|
|
What is the morphology of myotonic discharges?
|
biphasic single muscle fiber action potentials
|
|
|
In what 3 wasy are myotonic discharges triggered?
|
needle movement
percussion voluntary contraction |
|
|
What is the hallmark sign of myotonic discharges?
|
smooth change in rate and discharge
|
|
|
What is the sound of a myotonic discharge?
|
dive bomber
|
|
|
What is the origin of a myotonic discharge (pre- or post-junctional)?
|
postjunctional
|
|
|
What are 2 nerve disorder etiologies of myotonic discharges?
|
chronic radic
peripheral neuropathy |
|
|
What are 7 muscle disorder etiologies of myotonic discharges?
|
myotonic dystrophy
myotonia congenita paramyotonia polymyositis dermatomyositis acid-maltase deficieny hyperkalemic periodic paralysis |
|
|
What is a medication etiology of myotonic discharges?
|
propanolol
|
|
|
What is the hallmark of a fasciculation?
|
irregular firing motor unit
|
|
|
Can a fasciculation be a normal varient?
|
Yes
|
|
|
What is the origin (pre- or post-junctional) of a fasciculation?
|
pre-junctional
|
|
|
What does a fasciculation resemble?
|
MUAP
|
|
|
What is the rhythm of a fasciculation?
|
irregular
|
|
|
Does a fasciculation result in a muscle fiber contraction?
|
yes
|
|
|
For fasciculations to be considered abnormal they must be associated with what two wave forms?
|
PSWs
FIBs |
|
|
What are 5 nerve disorder etiologies of fasciculations?
|
anterior horn cell disease
tetany Creutzfeld-Jakob syndrome radiculopathy mononeuropathy |
|
|
What are two metabolic disorder etiologies of fasciculations?
|
thyrotoxicosis
tetany |
|
|
What are myokymic discharges?
|
groups of MUAPs firing repetetively.
|
|
|
What is the hallmark sign of myokymic discharges?
|
semiregularity between and within each dischage
|
|
|
What is the characteristic sound of myokymic discharges?
|
marching soldiers
|
|
|
What is the origin of myokymic discharges?
|
nerve
|
|
|
What are 4 facial myokymic nerve disorder etiologies of myokymic discharges?
|
Multiple sclerosis
brainstem neoplasm polyradiculopathy Bell's palsy |
|
|
What are 3 extremity myokymic nerve disorder etiologies of myokymic discharges?
|
radiation plexopathy
compression neuropathy rattlesnake venom |
|
|
What is the origin of neuromyotonic discharges?
|
motor axons
|
|
|
In what syndrome is a neuromyotonic discharge classically seen?
|
Isaac's syndrome (neuromyotonia)
|
|
|
What is the appearance of a neuromyotonic discharge?
|
tornado-like
|
|
|
What is the cause of the progressive decrement of a neuromyotonic discharge?
|
muscle fiber fatigue and drop-off
|
|
|
What is the sound of a neuromyotonic discharge?
|
musical (high frequency)
|
|
|
What are two nerve disorder etiologies of neuromyotonic discharges?
|
anterior horn cell disease
tetany |
|
|
What is a toxin etiology of a neuromyotonic discharge?
|
anticholinesterase
|
|
|
What are cramp discharges?
|
involuntary firing of MUAPs in a large area of the muscle
|
|
|
What is the rhythm of cramp discharges?
|
irregular
|
|
|
What are 8 etiologies of cramp discharges?
|
salt depletion
uremia pregnancy myxedema prolonged muscle contraction myotonia congenita myotonic dystrophy stiff-man's syndrome |
|
|
What is the recording range of a needle electrode?
|
5-15mm
|
|
|
What is measured in a MUAP amplitude?
|
most positive to most negative peak
|
|
|
What process can increase a MUAP amplitude?
|
reinnervation
|
|
|
What can cause a decrease in a MUAP amplitude?
|
loss of muscle fibers
|
|
|
What does a MUAP rise time represent?
|
proximity of needle to the motor unit
|
|
|
What does a MUAP duration represent?
|
number of muscle fibers within the motor unit
|
|
|
What increases a MUAP duration?
|
collateral sprouting
|
|
|
What decreases a MUAP duration?
|
loss to muscle fibers
|
|
|
How is duration measured?
|
initial departure from baseline to its final return
|
|
|
Do turns or serrations cross the baseline?
|
no
|
|
|
What do phases represent?
|
synchronicity of muscle fiber action potential firing
|
|
|
How are phases calculated?
|
baseline crossings + 1
|
|
|
Five or more baseline crossings represent what?
|
polyphasicity
|
|
|
Polyphasicity can occur how often (%) using a concentric/monopolar needle?
|
concentric: 15%
monopolar: 30% |
|
|
What is the origin (pre- or post-junctional) of MUAPs?
|
pre-junctional
|
|
|
The rate and rhythm or MUAPs is dependant on what?
|
exertion
|
|
|
What are 3 causes of polyphasicity?
|
fiber dropout
alterations of fiber CV collateral sprouting |
|
|
What is the cause of long duration, large amplitude polyphasic potentials?
|
denervation and reinnervation from collateral sprouting
|
|
|
What characteristic of long duration, large amplitude polyphasic potentials distinguish between a myopathic or neuropathic process?
|
recruitment pattern
|
|
|
What is the cause of short duration, small amplitude polyphasic potentials?
|
drop-out or dysfunction of muscle fibers
|
|
|
What are two categories of diseases in which short duration small amplitude potentials are seen?
|
myopathic diseases
NMJs diseases |
|
|
What are 2causes of satellite potentials?
|
incomplete myelin formation
immature terminal sprouts from chronic reinnervation or myopathy |
|
|
Name 5 conditions in which doublet or multiplet potentials are seen?
|
ischemia
hyperventilation tetany motor neuron disorder metabolic disease |
|
|
In what condition can giant potentials be seen?
|
poliomyositis
|
|
|
What is the onset frequency of the first MUAP recruitment (Hz)?
|
5 hz
|
|
|
What is the rule of 5s?
|
A new MUAP is recruited to fire at 5 Hz with each 5Hz increase in the first MUAP
|
|
|
Reduced recruitment is seen in what general conditions?
|
neuropathic conditions
|
|
|
Disruption of what nerve function can result in reduced recruitment?
|
axonal conduction
|
|
|
Early recruitment can be seen in what general disorder category?
|
myopathic conditions that result in a loss of muscle fibers
|
|
|
Early recruitment is due to what phenomenon?
|
loss of fibers causes less force generated per muscle unit
|
|
|
What is the firing rate formula?
|
FR=1000/interspike interval
|
|
|
What is the firing rate?
|
number of times an MUAP fires per second
|
|
|
What is the unit of measure for firing rate?
|
Hz
|
|
|
What is the recruitment frequency?
|
FR of first MUAP when a second MUAP begins to fire.
|
|
|
Above what recruitment frequency is considered neuropathic?
|
>20 Hz
|
|
|
What is the recruitment interval?
|
interspike interval between two discharges of the same MUAP when a second MUAP begins to fire
|
|
|
What is a normal recruitment interval in ms?
|
100ms
|
|
|
A decreased recruitment interval indicates what type of process?
|
neuropathy
|
|
|
An increased recruitment interval indicates what process?
|
myopathy
|
|
|
An increased recruitment frequency indicates what process?
|
neuropathy
|
|
|
A decreased recruitment frequency indicates what process?
|
myopathy
|
|
|
A decreased RI and an increased RF indicates what process?
|
neuropathy
|
|
|
An increased RI and a decreased RF indicates what process?
|
myopathy
|
|
|
A normal recruitment ratio is what?
|
<10
|
|
|
What is the formula for the recruitment ratio?
|
Dividing the FR of the first MUAP by the number of different MUAPs on the screen
|
|
|
When is the recruitment ratio used?
|
when a patient has difficulty controlling a contractile force
|
|
|
What is the interference pattern?
|
electrical activity recorded during maximal voluntary contraction
|
|
|
What the interference patten composed of?
|
recruitment plus activity
|
|
|
What is activation?
|
ability of motor unit to fire fast and produce greater contratile force: controlled centrally
|
|
|
What processes can decrease the interference pattern?
|
CNS diseases
pain hysteria poor cooperation |
|
|
What two measures can indicate an uncooperative patient when asked to generate a force?
|
few MUAPs
low Hz |
|
|
How many MUAPs are seen on the screen with a complete interference (normal)pattern during a full contraction?
|
4-5 MUAPs
|
|
|
Why is a radic usually more sensory than motor?
|
Due the larger size of the sensory fibers
|
|
|
A purely sensory radic would cause what type of NCS/EMG
|
normal
|
|
|
Why would a purely sensory radic show a normal NCS/EMG?
|
sparing of the DRG
|
|
|
What is the acronym for uncommon etiologies of radiculopathies? And what are the disorders for each letter of the acronym?
|
Hi Madam
H- herpes zoster I- Innflammatory - TB, Lyme, HIV, Syphillis, crypto, sarcoid M- Metastasis A - arachnoiditis, myelogram, surgery, steroids, anesthesia D - Diabetes A - Abscess M - Mass: meningioma, neurofibroma, leukemia, lipoma,cysts, hematoma |
|
|
What is the reduced reflex/weakness/paresthesia location for C5 nerve root lesion?
|
biceps/elbow flexion/lateral arm
|
|
|
What is the reduced reflex/weakness/paresthesia location for C6 nerve root lesion?
|
brarchioradialis/elbox flexion/lateral forearm
|
|
|
What is the reduced reflex/weakness/paresthesia location for C7 nerve root lesion?
|
triceps/elbow extension/middle finger
|
|
|
What is the reduced reflex/weakness/paresthesia location for C8 nerve root lesion?
|
none/finger flexion/medial forearm
|
|
|
What is the reduced reflex/weakness/paresthesia location for T1 nerve root lesion?
|
none/finger adduction/medial elbow
|
|
|
What is the reduced reflex/weakness/paresthesia location for L4 nerve root lesion?
|
patella/knee extension/medial ankle
|
|
|
What is the reduced reflex/weakness/paresthesia location for L5 nerve root lesion?
|
lateral hamstring/hallux extension/dorsal foot
|
|
|
What is the reduced reflex/weakness/paresthesia location for S1 nerve root lesion?
|
achilles/plantar flexion/lateral ankle
|
|
|
SNAP in radic is normal if the lesion is where?
|
proximal to the DRG
|
|
|
Under what 3 circumstances can a CMAP in a radic be normal?
|
demyelinating
incomplete reinnervation |
|
|
Typically, what is reduced in a radic CMAP?
|
reduced amplitude
|
|
|
The H-reflex may be abnormal in what level radic?
|
S1
|
|
|
What is the EDX criteria for radic?
|
FIBs or PSWs
2 muscles 2 nerves same root |
|
|
A C2-3 HNP affects what nerve root?
|
C3
|
|
|
What do the C2 and C3 nerves become?
|
greater and lesser occipital nerves
|
|
|
What is the motor distribution for C3 and C4
|
none
|
|
|
What sensory territory is covered by C3 and C4
|
posterior and lateral scalp
|
|
|
A C4-5 HNP affects what nerve?
|
C5
|
|
|
What 9 muscles are innervated by C5?
|
rhomboid
deltoid biceps suprapinatus infraspinatus brachialis BR supinator paraspinals |
|
|
What nerve is affected by a C5-6 HNP?
|
C6
|
|
|
What 10 muscles are affected by a C6 lesion?
|
deltoid
biceps BR supraspinatus infraspinatus supinator PT FCR EDC paraspinals |
|
|
What nerve is affected by a C6-7 HNP?
|
C7
|
|
|
What 5 muscles are affected by a C7 lesion?
|
PT
FCR EDC Triceps paraspinals |
|
|
What nerve is affected by a C7-T1 HNP?
|
C8
|
|
|
What muscles are affected by a C8 lesion?
|
Triceps
FCU FDP ADM FDI PQ APB paraspinals |
|
|
What roots are affected by L1-2, L2-3, and L3-4 HNPs?
|
L2 L3 L4
|
|
|
What 7 muscles are innervated by L2, L3, L4?
|
iliopsoas
iliacus gracilis adductor longus vastus medialis TA paraspinals |
|
|
A posterolateral L4-5 HNP affects what root?
|
L5
|
|
|
What 9 muscles are affected by a L5 lesion?
|
gluteus maximus
gluteus minimus TFL TA MG Medial hamstring TP PL paraspinals |
|
|
What nerve root is affected by a posterolateral L5-S1 HNP?
|
S1
|
|
|
What 8 muscles are affected by a S1 lesion?
|
gluteus maximus
gluteus medius TFL MG medial hamstring PL TP paraspinals |
|
|
What nerve roots are affected by cauda equina or spinal stenosis?
|
S2/3/4
|
|
|
What muscles are affected by a S2 lesion?
|
abductor hallicus
ADQ |
|
|
Compromise of S2/3/4 can affect what reflexes and functions?
|
bulbocavernosus
anal wink external sphincter tone bowel and bladder function |
|
|
What is the dual innervation of pectoralis major?
|
medial pectoral
lateral pectoral |
|
|
What is the dual innervation of brachialis?
|
musculotaneous
radial |
|
|
What is the dual innervation of the FDP?
|
median
ulnar |
|
|
What is the dual innervation of the lumbricals?
|
median
ulnar |
|
|
What is the dual innervation of the FPB?
|
median
ulnar |
|
|
What is the dual innervation of the pectineus?
|
femoral
obturator |
|
|
What is the dual innervation of the adductor magnus?
|
sciatic (tibial portion)
obturator |
|
|
What is the dual innervation of the biceps femoris?
|
sciatic (tibial portion)
sciatic (peroneal portion) |
|
|
What are 4 EDX finding present immediately in a radic?
|
decreased recruitment
decreased recruitment interval prolonged F wave abnormal H-reflex (with S1) |
|
|
What is an EDX finding at 4 days in a radic?
|
decreased CMAP amplitude (50% of opposite side)
|
|
|
Where does spontaneous activity first occur in a radic and when?
|
paraspinals
1 week |
|
|
Under what 2 scenarios can spontaneous activity be normal at 1 week in a radic?
|
reinnervation
posterior primary rami are spared |
|
|
What and where are the EDX findings at 2 weeks in a radic?
|
abnormal spontaneous activity in the limbs
|
|
|
What and where is the EDX finding at 3 week in a radic?
|
abnormal activity in paraspinals and limb
|
|
|
When is there evidence of reinnervation in a radic?
|
5-6 weeks
|
|
|
What is the EDX finding in a radic at 6mo-1yr?
|
increased amplitue from reinnervated motor unit
|
|
|
Where does a plexopathy take place in relation to the DRG?
|
distal
|
|
|
In a plexopathy the peripheral muscles on EMG will show abnormal activity, but what will show normal activity?
|
parapinals will be normal
|
|
|
What is the origin of the C5-T1 nerve roots?
|
ventral rami
|
|
|
Through which muscles do the ventral rami course?
|
anterior and middle scalenes
|
|
|
What two roots form the upper trunk
|
C5 and C6
|
|
|
What root forms the middle trunk?
|
C7
|
|
|
What roots form the lower trunk?
|
C8 and T1
|
|
|
Once the trunks pass what structure are they known as cords?
|
clavicle
|
|
|
The cords are named in relation to what structure?
|
axillary artery
|
|
|
What are the components of the posterior cord?
|
The posterior divisions of the upper, middle, and lower trunks
|
|
|
From what is the lateral cord comprised?
|
anterior divisions of the upper and middle trunk
|
|
|
From what is the medial cord comprised?
|
anterior division of the lower trunk
|
|
|
The lateral cord splits to form what branch?
|
musculotaneous branch
|
|
|
The lateral cord fuses with the medial cord to form what branch?
|
medial branch
|
|
|
The posterior cord splits into what two branches?
|
radial and axillary
|
|
|
The medial cord splits to contribute to what two branches?
|
median and ulnar branches
|
|
|
Where is the injury (roots and trunk) in a stinger?
|
C5-6 roots
upper trunk |
|
|
What is a common cause of Erb's palsy?
|
obstetrical injury
|
|
|
What is the classic presentation of Erb's palsy?
|
Waiter's tip position
|
|
|
Where is the stimulation done to assess Erb's point?
|
tip of C6 transverse process
|
|
|
Where is the site of injury(roots and trunk) in Klumpke's palsy?
|
C8-T1 nerve roots
lower trunk |
|
|
What is a common etiology of Klumpke's palsy?
|
obstetrical traction injury
|
|
|
What is a typical hand deformity in Klumpke's palsy?
|
claw hand
|
|
|
Claw hand deformity is due to weakness in what muscles?
|
lumbricals
|
|
|
Klumpke's palsy is also know as what?
|
lower trunk brachia plexopathy
|
|
|
Erb's palsy is also known as what?
|
Upper trunk brachial plexopathy
|
|
|
In Klumpke's palsy an EDX finding of preserved SNAP potential may indicate what?
|
nerve root avulsion
|
|
|
What response will be reduced or absent in a lower trunk brachial plexopathy?
|
medial antebrachial cutaneous sensory response
|
|
|
What are the circulatory structures involved in thoracic outlet syndrome?
|
subclavian artery
subclavian vein axillary vein |
|
|
What are 6 clincal signs of TOS?
|
ischemia
necrosis pain fatigue color changes temperature changes |
|
|
What is the incidince of neurogenic TOS?
|
1 in 1,000,000
|
|
|
In neurogenic TOS what trunk is compressed and where?
|
lower trunk between the first cervical rib and the clavicle
|
|
|
Where are the possible sites of lower trunk entrapment in neurogenic TOS?
|
between 1st cervical rib and the clavicle
scalene entrapment pectoralis minor muscle entrapment |
|
|
What are 2 clinical symptoms of neurogenic TOS?
|
medial forearm paresthesias and pain
hand muscle wasting |
|
|
What test is done to test for TOS?
|
Adson's test
|
|
|
In a positive Adson's test a loss pulse is due to compression of what structure?
|
subclavian artery
|
|
|
What SNAP is spared in TOS?
|
median SNAP
|
|
|
In TOS, what myotomes may show abnormal spontaneous activity?
|
C8-T1 myotomes
|
|
|
In TOS what muscles may show abnormal spontaneous activity?
|
median and ulnar hand muscles
|
|
|
Name two CMAPs that are abnormal in neurogenic TOS?
|
Ulnar and Median CMAP
|
|
|
What SNAP is abnormal in neurogenic TOS?
|
ulnar SNAP
|
|
|
What are 3 other names for neuralgic amyotrophy?
|
Parsonage Turner syndrome
brachial neuritis brial neuropathy |
|
|
In TOS rehab strengthening of what 3 muscles is done?
|
scapular stabilizers:
upper and middle trapezius rhomboids |
|
|
What is the etiology of parsonage turner syndrome?
|
unknown
|
|
|
What is the primary symptom of neuralgic amyotrophy?
|
pain in shoulder girdle region
|
|
|
What ROM exacerbates parsonage turner?
|
abduction and rotation
|
|
|
Is parsonage turner acute or gradual
|
acute
|
|
|
What percentage of parsonage turner present bilaterally?
|
Two-Thirds
|
|
|
How long can recovery take in parsonage turner?
|
2-3 years
|
|
|
Secondary plexus tumors can arise from what type of tumor?
|
Pancoast
|
|
|
Where is the primary Pancoast tumor usually located?
|
lung or breast
|
|
|
What are two nerve consequences of radiation therapy?
|
neural fibrosis
constriction of vasa nervorum |
|
|
A neoplastic plexopathy usually occurs in the upper or lower trunk?
|
lower
|
|
|
A radiation plexopathy usually occurs in upper or lower trunk?
|
upper
|
|
|
What is the clinical presentation of a radiation plexopathy?
|
myokymia
|
|
|
What is the clinical presentation of neoplastic plexopathy?
|
horner's syndrome
|
|
|
What is the pain of a radiation plexopathy?
|
painless
|
|
|
What is the pain of of neoplastic plexopathy?
|
painful
|
|
|
What root are most commonly avulsed? Why?
|
C8 and T1; due to less connective tissue support
|
|
|
What is a common presentation of a C8 or T1 nerve root avulsion?
|
flail shoulder
|
|
|
What are the 2 primary NCS EDX findings in a nerve root avulsion?
|
absent CMAP
normal SNAP |
|
|
What is the primary EMG EDX finding in nerve root avulsion?
|
absent recruitment
|
|
|
What nerve roots form the lumbar plexus?
|
L1-L4
|
|
|
What nerves roots form the sacral plexus?
|
L4-S4
|
|
|
What rami, ventral or dorsal, form the lumbar and sacral plexi?
|
ventral rami
|
|
|
The ventral rami divide to form what?
|
anterior and posterior divisions
|
|
|
The obturator nerve arises from what division of what plexus?
|
anterior division of the lumbar plexus
|
|
|
What nerves arise out of the posterior division of the lumbar plexus?
|
femoral and lateral femoral cutaneous nerves
|
|
|
The tibial and common peroneal nerves arise out of what plexus?
|
sacral plexus
|
|
|
The anterior division of the sacral plexus gives rise to what nerve?
|
tibial
|
|
|
The common peroneal nerve arises out of what sacral division?
|
posterior
|
|
|
The lumbosacral trunk arises out of what nerve roots?
|
L4 and L5
|
|
|
What structure connects the lumbar plexus to the sacral plexus? arising out of what nerve roots?
|
lumbosacral trunk/ L4 and L5
|
|
|
A retroperitoneal hematoma can form in what lumbar muscle?
|
psoas
|
|
|
What hip manifestation can occur as a result of a lumbar plexopathy?
|
hip dislocation
|
|
|
SNAPs can be elicited from what two nerves to dx a lumbar plexopathy?
|
saphenous or lateral femoral cutaneous
|
|
|
To dx a lumbar plexopathy CMAPs can be elicited from which nerve innervated muscles?
|
femoral innervated muscles
|
|
|
To dx a sacral plexopathy SNAP and CMAPs what nerve(SNAP) and nerve innervated muscles (CMAP) are tested?
|
SNAP- sural
CMAP - tibial and peroneal innervated muscles |
|
|
Obstetric injuries to the lumbar plexus can present with what symptom?
|
postpartum foot drop
|
|
|
What nerve roots contribute to the median nerve?
|
C5-T1
|
|
|
What muscles does the median nerve innervate distal to the median nerve? Acronym?
|
LOAF muscles + D
L lumbrical O opponens pollicis A abductor pollicis brevis F flexor pollicis brevis D digital cutaneous branches |
|
|
In what percentage of the population is the ligament of struthers found?
|
1%
|
|
|
Where is the Ligament of Struthers located in relation to the medial condyle?
|
3-6 cm proximal
|
|
|
In a Ligament of Struthers entrapment, what muscles may be involved?
|
all median innervated muscles
|
|
|
Grip strength weakness in a Ligament of Struthers entrapment is caused by what muscles?
|
flexor digitorum profundus
flexor digitorum superficialis |
|
|
Wrist weakness in a Ligament of Struthers entrapment is caused by what muscle?
|
flexor digitorum profundus
|
|
|
What sign may be present to due FDP weakness in the 2nd and 3rd digits?
|
benediction sign
|
|
|
What are the SNAP and CMAP findings in a Ligament of Struthers entrapment?
|
abnormal Median SNAP and CMAP
|
|
|
What are the EMG findings in Ligament of Struthers entrapment?
|
abnormal in median nerve-innervated muscles and the Pronator Teres (PT)
|
|
|
What nerve branches from the median?
|
Anterior interroseus nerve (AIN)
|
|
|
What muscles are innervated by the AIN?
|
FPL
FDP (1 and 2) PQ (pronator quadratus) |
|
|
What nerve can become entrapped during a venipuncture or ABG in the forearm, and what is the entrapping structure?
|
median nerve/bicipital aponeurosis
|
|
|
The EDX findings of an median nerve entrapment at the bicipital aponeurosis is similar to what?
|
Ligament of Struthers
|
|
|
Where is the median nerve typically entrapped in the forearm?
|
between the two heads of the pronator teres
|
|
|
What are the two heads of the pronator teres called?
|
ulnar head
humeral head |
|
|
What else in the forearm can trap the median nerve?
|
fascial band of the FDS as it bridges the two heads of the PT
|
|
|
The muscles involved in pronator teres syndrome can involve all muscles except what?
|
pronator teres, since its innervation is proximal to the entrapment
|
|
|
In PT syndrome what muscle causes finger flexion fatigue?
|
FDS
|
|
|
What are the NCS findings in PT syndrome?
|
abnormal median SNAPs and CMAPs
|
|
|
EMG in PT syndrome shows abnormalities in all median innervated muscles except what?
|
pronator teres
|
|
|
Anterior Interroseus Nerve (AIN) syndrome affects what part (sensory or motor) of that nerve?
|
motor
|
|
|
What muscle is the first to affected in AIN syndrome?
|
FPL
|
|
|
What muscles does the AIN supply?
|
FPL
PQ FDP 1,2 |
|
|
What are 3 etiologies of AIN syndrome?
|
fx in the forearm
laceration compression |
|
|
What function is completely spared in AIN syndrome?
|
sensory
|
|
|
What sign is typical in AIN syndrome?
|
OK sign
|
|
|
Weakness in what muscles cause the OK sign?
|
FPL, FDP, PQ
|
|
|
What are the normal NCS findings in AIN syndrome?
|
normal median nerve SNAP
normal CMAP to the APD |
|
|
What is an abnormal NCS finding in AIN syndrome?
|
CMAP to pronator quadratus (PQ)
|
|
|
What are the positive EMG findings in AIN syndrome?
|
abnormal activity in FPL, FDP 1 and 2, PQ
|
|
|
The OK sign in AIN is caused by weakness in what two muscles?
|
FPL and FDP
|
|
|
What are the nerve and muscle (and number of tendons) contents of the carpal tunnel?
|
FDS (4)
FDP (4) FPL (1) median nerve |
|
|
What are the bony and ligamentous borders of the carpal tunnel?
|
carpal bones
transverse carpal ligament |
|
|
What flexor is NOT in the carpal tunnel?
|
FCR (flexor carpi radialis)
|
|
|
At what month in pregnancy does CTS usually appear?
|
6 months, then disappears post-delivery
|
|
|
In CTS weakness can occur in what muscles? Acronym?
|
LOAF
L lumbricals 1 and 2 O oppens pollicis A abductor pollicis brevis F flexor digitorum superficialis - 4 heads |
|
|
Where are sensory abnormalities noted in CTS?
|
lateral 3 1/2 fingers except the base of the thumb
|
|
|
Holding the wrist at 90 degrees for 1 minute is what test?"
|
Phalen's test
|
|
|
What is reverse Phalen's test?
|
holding the wrist in 90 degrees extention for 1 minute
|
|
|
How long should the carpal compression test be conducted?
|
30 seconds
|
|
|
What are the NCS/EMG findings in mild CTS?
|
SNAP prolonged latency
CMAP normal EMG normal |
|
|
What are the NCS/EMG findings in moderate CTS?
|
SNAP prolonged latency and decreased amplitued
CMAP prolonged latency EMG normal |
|
|
What are the NCS/EMG findings in sereve CTS?
|
SNAP absent
CMAP prolonged latency and decreased amplitude EMG: abnormal activity |
|
|
What is a special CTS EDX test?
|
orthodromic midpalmer NCS
|
|
|
What can atrophy in severe CTS?
|
thenar eminence
|
|
|
How long is Phalen's test conducted?
|
one minute
|
|
|
Name 6 indicators of poor outcome in CTS.
|
Sxs > 10 months
Phalen's +<10 seconds atrophy constant paresthesias marked prolonged latency on NCS abnormal spontaneous activity on EMG |
|
|
What are the two nerves and direction of the Martin Gruber anastamosis?
|
median to ulnar
|
|
|
What fibers of the median anastamose with the ulnar nerve?
|
AIN branch of the median to the ulnar
|
|
|
A Martin Gruber anastamosis occurs in what percentage of the population
|
15-20%
|
|
|
What is an alternative Martin Gruber anastamosis?
|
proximal median to ulnar and innervates the ADP, ADM and first DI
|
|
|
What is the most commonly innervated muscle in Martin Gruber?
|
first DI
|
|
|
What is an EDX finding in Martin Gruber?
|
initial positive deflection of the CMAP at the elbow, which is not seen at the wrist
|
|
|
What EDX phenomenon causes an initial CMAP positive deflection in Martin Gruber?
|
volume conduction causes stim to reach ulnar muscles before the median nerve as a result of median nerve being trapped at the carpal tunnel
|
|
|
What are three EDX findings in Martin Gruber?
|
*CMAP positive deflection at the elbow, and not at the wrist
*Increased median CMAP amplitude at the elbow *artificially fast CV |
|
|
Why is there an increased median nerve CMAP amplitude at the elbow in Martin Gruber?
|
Simultaneous stim of median and ulner muscles at the elbow, even without median nerve entrapment
|
|
|
What is the direction and involved nerves seen in the Riche-Cannieu anastamosis?
|
Recurrent branch of the median nerve in the hand to the motor branch of the ulnar
|
|
|
What is the muscle innervation consequence of a Riche-Cannieu anastamosis?
|
an all ulner innervated hand
|
|
|
What is the primary EDX finding in the Riche Cannieu anastamosis?
|
Recording over the APB (a median innervated hand muscle) the CMAP is absent with median stim, but present with ulnar stim
|
|
|
What nerve roots contribute to the ulnar nerve?
|
C8 and T1
|
|
|
C8 and T1 nerve roots contribute to what trunk(s) and cord(s)?
|
lower trunk
medial cord |
|
|
What nerve runs in the Arcade of Struthers?
|
ulnar
|
|
|
In what elbow groove does the ulnar run?
|
retrocondylar groove
|
|
|
Name 2 ulnar innervated muscles in the cubital tunnel
|
flexor carpi ulnaris
flexor digitorum profundus |
|
|
What are the 3 ulnar branches off Guyon's canal?
|
superficial sensory branch
hypothenar branch deep motor branch |
|
|
What are the 3 muscles innervated by the hypothenar branch?
|
opponens digiti quinti
abductor digiti quinti flexor digiti quinti |
|
|
What are the muscles innervated by the Deep Motor Branch and acronyms?
|
DAB 4 Dorsal interossei - ABduction
PAD 4 Palmar interossei -ADduction 2 lumbrical 1 adductor pollicis 1/2 flexor pollicis brevis (deep head) |
|
|
What is the 1 1/2 nerve?
|
Ulnar is the 1 1/2 nerve
|
|
|
What are the 1 1/2 ulnar innervated muscles of the thumb?
|
1 adductor
1/2 flexor pollicis brevis (deep head) |
|
|
What are the 1 1/2 ulnar-innervated muscles of the forearm?
|
1 flexor carpi ulnaris
1/2 flexor digitorum profundus (3,4) |
|
|
What are the 1 1/2 ulnar sensory areas of the hand?
|
5th digit
1/2 fourth digit |
|
|
What does the Arcade of Struthers connect?
|
fascial band that connects the brachialis to triceps brachii
|
|
|
An entrapment of the ulnar nerve at the arcade of struthers may results in radial deviation upon wrist flexion due to weakness of what muscle?
|
FCU
|
|
|
An entrapment at what structure may involve all ulnar muscles and all ulnar sensory branches?
|
arcade of struthers
|
|
|
What is ulnar claw hand caused by?
|
unopposed pull of EDC
|
|
|
Innability to hold a piece of paper by the thumb and index finger is called what sign?
|
Froment's sign
|
|
|
What muscle is weakened in Froment's sign, and what is the innervation?
|
adductor pollicis
deep motor branch of the ulnar (guyon's canal) |
|
|
What muscle/nerve is substituted for adductor pollicis weakness in Froment's sign?
|
FPL
median |
|
|
What sign is the inability to adduct the fifth digit?
|
Wartenberg's sign
|
|
|
Wartneberg's sign is due to weakness in what muscle?
|
interossei
|
|
|
What are 3 possibly positive signs in ulnar nerve entrapment at the arcade of struther?
|
ulnar claw hand
froment's sign wartenberg's sign |
|
|
What are the 2 sensory NCS EDX findings in ulnar entrapment at the arcade of struthers?
|
abnormal SNAP of dorsal ulnar cutaneous (DUC) and ulnar nerve
|
|
|
What is the motor NCS EDX findings in ulnar entrapment at the arcade of struthers?
|
abnormal ulnar CMAP
|
|
|
What are the EMG EDX findings in ulnar entrapment at the arcade of struthers?
|
abnormal activity in all ulnar innervated muscles
|
|
|
What neuropathy can occur months to years after a distal humerus fracture?
|
tardy ulnar nerve palsy
|
|
|
What fracture can cause a tardy ulnar nerve palsy?
|
distal humerus fracture
|
|
|
What muscles are involved in a tardy ulnar nerve palsy?
|
all ulnar innervated muscles
|
|
|
What are the EMG EDX findings in a ulnar nerve entrapment at the arcade of struthers?
|
abnormal activity in all ulnar innervated muscles
|
|
|
What are the NCS EDX findings in tardy ulnar nerve palsy?
|
abnormal ulnar SNAP and CMAPs
|
|
|
Where is the most common site of ulnar entrapment?
|
cubital tunnel
|
|
|
What are two possible locations of ulnar entrapment at the cubital tunnel?
|
FCU aponeurosis
arcuate ligament |
|
|
What are the 2 bony borders of the cubital tunne?
|
medial epicondyle
olecranon |
|
|
At what angle range of elbow flexion should the ulnar NCS be performed?
|
90-110 degrees
|
|
|
What muscles are affected by ulnar compression at the cubital tunnel?
|
all ulnar innervated muscles except the FCU
|
|
|
What muscle may or may not be affected by ulnar compression at the cubital tunnel?
|
FCU
|
|
|
What are the sensory NCS EDX findings in cubital tunnel syndrome?
|
abnormal dorsal ulnar cutaneous and ulnar SNAPs
|
|
|
What are the 2 motor NCS EDX findings in cubital tunnel syndrome?
|
*Ulnar CMAP shows 10-15 msec drop in CV across the elbow
*20% amplitude drop |
|
|
What 3 branches of the ulnar nerve may be affected at or proximal to Guyon's canal?
|
deep ulnar
hypothenar superficial ulnar sensory |
|
|
What are the 4 possible patterns of ulnar entrapment at the wrist?
|
*pure motor: deep palmar motor branch
*pure motor: deep palmar and hypothenar branches *mixed motor and sensory *pure sensory |
|
|
Where in guyon's canal will a mixed motor and sensory ulnar lesion occur?
|
proximal canal
|
|
|
Which sensory area is affected by a pure sensory lesion of the ulnar nerve in Guyon's canal?
|
volar 4th and 5th fingers
|
|
|
Name three common etiologies of ulnar compression at Guyon's canal
|
*cycling sports
*wrist ganglion *rheumatoid arthritis |
|
|
Which muscles are affected by ulnar compression at Guyon's canal?
|
ulnar innervated intrinsic muscles of the hand
|
|
|
Name 2 common symptoms of ulnar compression at Guyon's canal.
|
*painless wasting of 1st DI
*claw hand |
|
|
What is the cause of claw hand? What muscle remains intact? and what happens?
|
lumbrical weakness while FDP remains intact, causing marked finger flexion
|
|
|
What sensory nerve is spared in ulnar compression at Guyon's canal?
|
dorsal ulnar cutaneous
|
|
|
What is the sensory NCS EDX finding in ulnar compression at Guyon's canal?
|
ulnar SNAP to 5th digit is abnormal
|
|
|
What is the motor NCS EDX finding in ulnar compression at Guyon's canal?
|
abnormal ulnar SNAP
|
|
|
What are the EMG EDX findings in ulnar compression at the Guyon's canal?
|
abnormal activity in ulnar innervated hand muscles
|
|
|
What are the nerve roots contributing the the radial nerve?
|
C5-T1
|
|
|
To what trunk(s) and cord(s) do the nerve root origins of the radial nerve contribute?
|
upper, middle, and lower trunks
psterior cord |
|
|
What is the radial nerve's orientation in the arm relative to the axillary artery?
|
radial nerve is posterior to the axillary artery
|
|
|
Through what heads of the does the radial nerve travel?
|
long and medial heads of the triceps
|
|
|
What two muscles are innervated by the radial proximal to the spiral groove?
|
triceps
anconeus |
|
|
What two nerves branch off the radial proximal to the spiral groove?
|
posterior cutaneous nerve
lower lateral cutaneous nerve |
|
|
What two muscles are innervated by the radial distal to the spiral groove?
|
brachioradialis
extensor carpi radialis longus |
|
|
What nerve branches off the radial distal to the spiral groove?
|
posterior cutaneous nerve of the forearm
|
|
|
What structure does the radial nerve pierce 10cm proximal to the lateral epicondyle?
|
lateral intermuscular septum
|
|
|
Just proximal to the lateral epicondyle the radial nerve travels between what two muscles?
|
brachialis
brachioradialis |
|
|
Into what two nerves and where does the radial nerve split at the elbow?
|
superficial radial nerve
posterior interosseus nerve at the lateral epicondyle |
|
|
What is the innervation of the extensor carpi radialis brevis? above or below the elbow?
|
posterior interosseus nerve
below |
|
|
What is innervation of the extensor carpi radialis longus and where?
|
radial nerve
distal to the spiral groove |
|
|
Name 9 posterior interrosseus innervated muscles.
|
extensor carpi radialis brevis
supinator extensor digitorum communis extensor digiti minimi extensor carpi ulnaris abductor pollicis longus extensor pollicis longus extensor pollicis brevis extensor indicis proprius |
|
|
What 3 nerves can be affected by an axilla injury?
|
radial
axillary suprascapular |
|
|
In a crutch palsy what muscles may be affected?
|
all radial innervated muscles including the triceps
|
|
|
In what two locations are the sensory deficits in crutch palsy?
|
posterior arm
forearm |
|
|
What are the NCS (motor and sensory) EDX findings in crutch palsy?
|
SNAP and CMAP abnormalities
|
|
|
What are the EMG EDX findings in crutch palsy?
|
abnormal activity in all radial innervated muscles
|
|
|
Where is the location of Saturday night or honeymooner's palsy?
|
spiral groove
|
|
|
What is a common cause of radial nerve damage in the spiral groove?
|
humerus fracture
|
|
|
What two muscles are spared in radial nerve damage at the spiral groove?
|
triceps
anconeus |
|
|
What function is spared in radial injury at the spiral groove?
|
elbow extension (triceps and anconeus)
|
|
|
What are 4 hallmark symtoms of radial injury at the spiral groove?
|
weakness in
elbow flexion supination wrist drop finger extension |
|
|
Wrist drop in radial injury at the spinal groove is due to weakness in what muscles?
|
ECR-L
ECR-B ECU |
|
|
Weakness in elbow flexion in radial injury at the spiral groove is due to what muscle?
|
brachioradialis
|
|
|
Weakness in supination in a radial injury at the spiral groove is due to what muscle?
|
supinator
|
|
|
Where are the sensory deficity in radial injury at the spiral groove?
|
dorsal aspect of hand
posterior forearm |
|
|
What are the EMG EDX findings in radial injury at the spiral groove?
|
abnormal activity in all radial muscles below the spiral groove
|
|
|
Lead causes what type of neuropathy?
|
diffuse polyneuropathy
|
|
|
What are 7 peripheral causes of wrist drop?
|
diffuse polyneuropathy: lead
mononeuropathy: PIN, radial plexopathy: upper or middle trunk; posterior cord radiculopathy: C6 and C7 |
|
|
What are three central causes of wrist drop?
|
SCI
TBI CVA |
|
|
Radial tunnel syndrome can be caused by an entrapment of the radial nerve between what two muscles?
|
brachialis
brachioradialis |
|
|
Radial tunnel syndrome can mimic what other syndrome?
|
tennis elbow
|
|
|
Reproduction of radial tunnel syndrome symptoms can be done by what 3 maneuvers?
|
*resisted extension of 3rd digit during elbow extension
*resisted supination *palpation of radial head |
|
|
What is tennis elbow also known as?
|
lateral epicondylitis
|
|
|
What two maneuvers can reproduce lateral epicondylitis?
|
*palpation of lateral epicondyle
less pain on resisted *supination |
|
|
What are the EDX findings in radial tunnel syndrome?
|
none
|
|
|
What are two other names for posterior interosseus syndrome?
|
supinator syndrome
arcade of frohse syndrome |
|
|
What is the nature of PIN syndrome? (motor or sensory)?
|
pure motor
|
|
|
What are two etiologies of PIN syndrome?
|
compression of the PIN at the arcade of Frohse
Monteggia fracture |
|
|
What is a Monteggia fracture?
|
fx of proximal 1/3 of the ulna
|
|
|
What is the mechanism of a Monteggia fracture?
|
fall on outstretched hand with forearm locked in full pronation
|
|
|
What muscles are involved in PIN syndrome?
|
EDC
EIP ECU EPB EPL APL |
|
|
What muscles are ALWAYs spared in PIN syndrome?
|
brachioradialis
triceps ECR-L ECR-B anconeus |
|
|
What sense is spared in PIN syndrome?
|
sensation
|
|
|
In what syndrome may pseudo claw hand deformity be seen and what is it?
|
PIN syndrome
finger extensor weakness |
|
|
What symptoms wrist sx is seen in PIN syndrome? why?
|
radial deviation with wrist extension
ECU weakness |
|
|
What is the sensory NCS EDX finding in PIN syndrome?
|
normal radial SNAP
|
|
|
What is the motor NCS EDX finding in PIN syndrome?
|
abnormal CMAP in PIN innervated muscles
|
|
|
What are the EMG EDX findings in PIN syndrome?
|
abnormal activity in PIN-innervated muscles
|
|
|
Superficial radial neuropathy is also known as what?
|
wristwatch syndrome (handcuff syndrome)
|
|
|
What is the nature of a superficial radial neuropathy?
|
pure sensory
|
|
|
Where is the sensory deficit in superficial radial neuropathy?
|
dorsal radial aspect of hand
|
|
|
In what 2 ways can discomfort be exacerbated in superficial radial neuropathy?
|
*palmar and ulnar wrist flexion
*forced pronation |
|
|
Over what muscle does the superficial radial nerve run?
|
extensor carpi radialis
|
|
|
What separates the superficial radial nerve from the extensor carpi radialis?
|
extensor retinaculum
|
|
|
What are the sensory NCS EDX finding(s) in wristwatch syndrome?
|
abnormal radial nerve SNAP
|
|
|
What are the motor NCS EDX findings in superfical radial neuropathy?
|
none
|
|
|
What is the EMG EDX finding in superficial radial neuropathy?
|
none
|
|
|
What nerve roots contribute to the musculocutaneous nerve?
|
C5, C6, and C7
|
|
|
Nerve fibers contributing to the musculocutaneous nerve pass through what trunk(s) and cord(s)?
|
upper trunk
lateral cord |
|
|
What 3 muscles does the musculocutaneous nerve innervate?
|
coracobrachialis
biceps brachialis |
|
|
What is the dual innervation of the brachialis?
|
radial
musculocutaneous |
|
|
What is the sensory branch of the musculocutaneous nerve?
|
lateral antebrachial cutaneous nerve
|
|
|
What part of the musculocutaneous nerve is more commonly injured, proximal or distal?
|
distal
|
|
|
What muscle proximally can trap the musculotaneous nerve?
|
coracobrachialis
|
|
|
Musculotaneous neuropathy spares what musculotaneous innervated muscle?
|
coracobrachialis
|
|
|
What is a typical symptom of musculotaneous neuropathy?
|
elbow flexion weakness
|
|
|
What is distribution of sensory deficits in musculotaneous neuropathy?
|
lateral forearm
|
|
|
What are the sensory NCS EDX findings in musculotaneous neuropathy?
|
abnormal SNAP in the lateral antebrachial cutaneous nerve
|
|
|
What are the motor NCS EDX findings in musculotaneous neuropathy?
|
abnormal CMAP in the biceps
|
|
|
What are the EMG EDX findings in musculotaneous neuropathy?
|
abnormal activity in the brachialis and brachioradialis
|
|
|
What nerve roots contribute to the axillary nerve?
|
C5 and C6
|
|
|
Through what trunk(s) and cord(s) do the components of the axillary nerve run?
|
upper trunk
posterior cord |
|
|
What 2 muscles are innervated by the axillary nerve?
|
teres minor
deltoid |
|
|
What cutaneous nerve is a branch of the axillary?
|
upper lateral cutaneous
|
|
|
What are the borders of the quadrangular space?
|
humerus
long head of the triceps teres minor teres major |
|
|
What three motions of the shoulder are weakened in axillary neuropathy?
|
flexion
abduction external rotation |
|
|
What is the function of teres minor?
|
external rotation
|
|
|
What is the function of the deltoid muscle?
|
flexion
abduction |
|
|
What is abnormal in NCS EDX of axillary neuropathy?
|
CMAP is abnormal
|
|
|
What are the EMG EDX findings in axillary neuropathy?
|
abnormal activity in teres minor and deltoid
|
|
|
What nerve roots contribute to the suprascapular nerve?
|
C5 and C6
|
|
|
Components of the suprascapular nerve travel through which trunk?
|
upper trunk
|
|
|
What muscle does the suprascapular nerve innervate?
|
supraspinatus and infraspinatus
|
|
|
What ligament covers the suprascapular notch?
|
transverse scapular ligament
|
|
|
What muscle is innervated by the suprascapular nerve proximal and distal to the spinoglenoid notch
|
supraspinatus proximal
infraspinatus distal to the spinoglenoid notch |
|
|
What is the only peripheral neuropathy at the trunk level?
|
suprascapular neuropathy
|
|
|
What sport is commonly involved with a suprascapular neuropathy?
|
volleyball- overhead serve
|
|
|
Which suprascapular innervated muscles are affected in a suprascapular neuropathy?
|
both-
suprspinatus infraspinatus |
|
|
Suprascapular neuropathy can present as weakness in what muscles with what action?
|
supraspinatus/abduction
infraspinatus/external rotation |
|
|
Entrapment at the suprascapular notch results in atrophy of which muscle(s)?
|
atrophy of infraspinatus and supraspinatus
|
|
|
Entrapment at the spinoglenoid not results in atrophy of what muscle(s)?
|
infraspinatus alone
|
|
|
What are the sensory NCS EDX findings in supraspinatus neuropathy?
|
SNAP- not available
|
|
|
What is the motor NCS EDX finding in supraspinatus neuropathy?
|
CMAP is abnormal.
|
|
|
What are the EMG EDX findings in suprascapular neuropathy?
|
abnormal activity
|
|
|
What nerve roots contribute to the long thoracic nerve?
|
C5, C6, and C7 nerve roots
|
|
|
What nerve innervates the serratus anterior?
|
long thoracic
|
|
|
What single muscle does the long thoracic nerve innervate?
|
serratus anterior
|
|
|
Medial scapular winging is due to weakness of what muscle? What nerve injury?
|
serratus anterior/long thoracic nerve injury
|
|
|
Lateral winging of the scapular is due to weakness of what muscle? What nerve injury?
|
trapezius weakness/spinal accessory nerve injury
|
|
|
Shoulder abduction of medial winging (serratus anterior weakness/long thoracic nerve injury) increases or decreases winging?
|
decreases winging
|
|
|
Shoulder abduction of lateral winging (trapezius weakness/spinal accessory nerve) increases or decreases winging?
|
increases winging
|
|
|
Do the fiber contributors of long thoracic nerve travel through any trunks/cords?
|
No
|
|
|
What is the sensory NCS EDX finding of long thoracic neuropathy?
|
Not available
|
|
|
What is the motor NCS EDX finding o long thoracic neuropathy?
|
CMAP abnormal
|
|
|
What is the EMG EDX finding in long thoracic neuropathy? What muscle?
|
abnormal in serratus anterior
|
|
|
What are the root origins of the lateral femoral cutaneous nerve?
|
L2 and L3
|
|
|
To what division of the lumbar plexus do L2 and L3 contribute?
|
posterior division
|
|
|
What is the sensory distribution of the lateral femoral cutaneous nerve?
|
lateral thigh
|
|
|
How does the lateral femoral cutaneous pass by the inguinal ligament (i.e. over or under)?
|
under the inguinal ligament
|
|
|
An injury to the lateral femoral cutaneous nerve is called what?
|
meralgia paresthestica
|
|
|
What hip motion exacerbates meralgia paresthetica?
|
hip extension
|
|
|
What are the sensory NCS EDX findings in meralgia paresthetica? Motor?
|
abnormal SNAP in the lateral femoral cutaneous nerve
motor CMAP is normal |
|
|
What are the root origins of the femoral nerve?
|
L2, L3, and L4
|
|
|
To what division of the lumbar plexus do the roots of the femoral nerve contribute?
|
posterior division
|
|
|
What is the femoral nerve's position relative to the femoral artery?
|
lateral to the femoral artery
|
|
|
What 4 muscles are innervated by the femoral nerve?
|
iliacus
pectinius (1/2) sartorius quads |
|
|
What nerve continues from the femoral nerve?
|
saphenous nerve
|
|
|
What nerve is the largest branch of the lumbar plexus?
|
femoral nerve
|
|
|
What is a common weakness seen in femoral neuropathy?
|
weak knee extension (quads)
|
|
|
What is a common sensory deficit seen in femoral neuropathy?
|
anterior thigh and medial leg
|
|
|
What is the sensory NCS EDX findings in femoral neuropathy?
|
abnormal SNAP in saphenous nerve
|
|
|
What is the motor NCS EDX finding in femoral neuropathy?
|
abnormal CMAP in the rectus femoris
|
|
|
What is the EMG EDX finding in femoral neuropathy?
|
abnormal activity in femoral nerve innervated muscles
i.e. sartorius quads pectinius (1/2) iliacus |
|
|
Abnormal EMG findings in the adductor longus muscle could indicate what neuropathy?
|
L3/4 neuropathy
|
|
|
What is the most common cause of femoral neuropathy?
|
diabetic amyotrophy
|
|
|
In what two other conditions can diabetic amyotrophy be seen?
|
polyradiculopathy
lumbar plexopathy |
|
|
What is the pathologic injury in diabetic amyotrophy?
|
vaso-nevorum
|
|
|
Diabetic amyotrophy has been noted after what phenomenon?
|
marked weight loss
|
|
|
What are 3 possible symptoms of diabetic amyotrophy?
|
asymmetric thigh pain
knee extension weakness (quads) loss of patella reflex |
|
|
What are the sensory and motor NCS EDX findings in diabetic amyotrophy?
|
abnormal SNAP
abnormal CMAP |
|
|
In what 3 muscles may there be found abnormal EMG findings in diabetic amyotrophy?
|
adductors
iliopsoas parapinals |
|
|
What is the largest and longest nerve branch of the the femoral nerve?
|
saphenous nerve
|
|
|
What 3 sensory areas does the saphenous nerve supply?
|
medial leg
medial malleolus medial arch |
|
|
In what 2 places can the saphenous nerve be trapped?
|
*Hunter's canal - subsartorial
*between sartorius and gracilis |
|
|
What is the nature of a saphenous neuropathy (sensory or motor or both)?
|
pure sensory
|
|
|
What is a typical complaint in saphenous neuropathy?
|
knee pain
|
|
|
What are the sensory and motor NCS and EMG EDX findings in saphenous neuropahty?
|
abnormal saphenous SNAP
normal motor CMAP normal EMG |
|
|
What are the root origins of the obturator nerve?
|
L2, L3, and L4
|
|
|
To what division of the lumbar plexus do the roots of the obturator nerve contribute?
|
anterior
|
|
|
What 6 muscles does the obturator innervate?
|
pectineus (1/2)
adductor brevis adductor longus adductor magnus obturator externus gracilis |
|
|
What nerve branches off the obturator nerve?
|
cutaneous branch
|
|
|
What other nerve is commonly injured along with the obturator?
|
femoral nerve
|
|
|
What is a common symptom of obturator neuropathy? From what muscles?
|
hip adduction weakness
adductor brevis adductor longus adductor magnus |
|
|
What is the sensory NCS EDX finding in obturator neuropathy?
|
none
|
|
|
What is the sensory area affected by an obturator neuropathy?
|
medial thigh
|
|
|
What are the root origins of the sciatic nerve?
|
L4-S3
|
|
|
To what division of the lumbar plexus do the roots of the sciatic nerve contribute?
|
posterior division
|
|
|
What are the two portions of the sciatic nerve? What are the relative postions of each?
|
tibial - medial
peroneal - lateral |
|
|
Through what structure does the sciatic nerve exit the pelvis?
|
greater sciatic foramen
|
|
|
What are the two bony landmarks between which the sciatic nerve travels in the buttock?
|
greater trochanter
ischial tuberosity |
|
|
What muscle does the peroneal branch innervate?
|
short head of the biceps femoris
|
|
|
What 4 muscles does the tibial branch of sciatic nerve innervate?
|
long head of the biceps femoris
semitendinosis semimembranosus adductor magnus |
|
|
What tibial branch innervated muscle is also innervated by the obturator?
|
adductor magnus
|
|
|
What is the largest nerve in the human body?
|
sicatic
|
|
|
What portion of the sciatic nerve is made up by the peroneal nerve?
|
outer 2/3rds
|
|
|
What portion of the sciatic nerve is affected by piriformis syndrome?
|
peroneal
|
|
|
The sciatic nerve runs in what relation to the piriformis muscle?
|
through it
or inferior |
|
|
What is a typical weakness in piriformis syndrome?
|
knee flexion weakness (hamstring)
|
|
|
What are 2 sensory NCS EDX findings in sciatic neuropathy?
|
abnormal superficial peroneal and sural SNAPs
|
|
|
What are 2 motor NCS EDX findings in sciatic neuropathy?
|
abnormal tibial and peroneal CMAPs
|
|
|
What are two EMG EDX findings in sciatic neuropathy?
|
abnormal activity in all sciatic innervations including
short head of the biceps femoris long head of th biceps femoris |
|
|
What are the roots of the tibial nerve?
|
L4-S3
|
|
|
Where does the sciatic branch into the tibial nerve?
|
popliteal fossa
|
|
|
At the posterior knee what 5 muscles does the tibial nerve innervate?
|
plantaris
medial gastroc lateral gastroc popliteus soleus |
|
|
At the soleus muscle the tibial continues distally as what nerve?
|
posterior tibial nerve
|
|
|
What 3 muscles does the posterior tibial innervate?
|
tibialis posterior
flexor digitorum longus flexor hallicus longus |
|
|
Into what 3 nerves does the posterior tibial nerve branch at the flexor retinaculum?
|
medial plantar nerve
lateral plantar nerve calcaneal nerve |
|
|
What 5 muscles does the medial plantar nerve innervate?
|
adductor hallicus
flexor digitorum brevis flexor hallicus brevis lumbricals |
|
|
What nerve branches off the medial plantar nerve?
|
sensory branch
|
|
|
What 5 muscles does the lateral plantar nerve innervate?
|
lumbricals
abductor digiti minimi quadratus plantae interossei adductor hallucis |
|
|
What muscle does the calcaneal nerve innervate?
|
none
|
|
|
What is the nerve branch of the calcaneal nerve?
|
sensory branch
|
|
|
What is tibial nerve entrapment called?
|
tarsal tunnel syndrome
|
|
|
What are the contents of the tibial tunnel? Mnemonic?
|
Tom-Tibialis posterior
Dick-flexor Digitorum longus And-posterior tibial Artery Very-posterior tibial Vein Nervous-tibial Nerve Harry-flexor Hallicus longus |
|
|
What structure can compress the tibial nerve?
|
flexor retinaculum
|
|
|
What sensory distribution is spared in tarsal tunnel syndrome, and why?
|
heel sensation due to calcaneal branch
|
|
|
Symptoms of tarsal tunnel can be reproduced by what ankle position?
|
ankle inversion
|
|
|
What is the sensory NCS EDX finding in tarsal tunnel syndrome?
|
abnormal plantar SNAPs
|
|
|
What is the calcaneal SNAP in tarsal tunnel?
|
normal
|
|
|
What are the 2 motor NCS EDX findings in the tarsal tunnel?
|
abnormal medial and lateral plantar CMAPs
|
|
|
What are the EMG EDX findings in tarsal tunnel?
|
abnormal activity in all tibial nerve innervated muscles
|
|
|
What 3 muscles are contained in the tarsal tunnel?
|
tibialis posterior
flexor digitorum longus flexor hallucis longus |
|
|
What are the root origins of the peroneal nerve?
|
L4-S2
|
|
|
The peroneal runs with/as what other nerve until the distal posterior thigh?
|
sciatic
|
|
|
What nerve is a continuation of the peroneal nerve?
|
common peroneal nerve
|
|
|
What are the two branches of the common peroneal nerve?
|
superficial peroneal nerve
deep peroneal nerve |
|
|
Where does the common peroneal split into its two branches?
|
fibular head
|
|
|
What 2 muscles does the superficial peroneal nerve innervate?
|
peroneus longus
peroneus brevis |
|
|
What are the two nerve branches of the superfical peroneal nerve?
|
medial cutaneous nerve
lateral cutaneous nerve |
|
|
What 6 muscles does the deep peroneal nerve innervate?
|
tibialis anterior
extensor digitorum longus extensor hallicus longus peroneus tertius extensor digitorum brevis first dorsal interossei |
|
|
What is the cutaneous nerve branch of the deep peroneal nerve?
|
dorsal distal cutaneous nerve
|
|
|
What is the anomalous nerve branch from the superficial peroneal nerve?
|
accessory peroneal nerve
|
|
|
What does the accessory peroneal nerve innervate?
|
extensor digitorum brevis
|
|
|
Behind what malleolus does the accessory peroneal nerve travel?
|
lateral
|
|
|
What muscle can be spared even with at deep peroneal nerve injury?
|
extensor digitorum brevis
|
|
|
Where is the site of the most common injury to the common peroneal nerve?
|
fibular head
|
|
|
What is strawberry picker's palsy?
|
common peroneal neuropathy
|
|
|
What neuruopathy can prolonged squatting cause?
|
common peroneal neuropathy
|
|
|
What muscle is spared in a common peroneal neuropathy at the fibular head?
|
short head of the biceps femoris
|
|
|
What muscle action and muscles are weakened in a common peroneal neuropathy the fibular head?
|
dorsiflexion is weak
tibialis anterior extensor digitorum longus extensor hallucis longus |
|
|
What gait pattern occurs with common peroneal nerve injury at the fibular head?
|
steppage gait
|
|
|
What foot condition results from a common peroneal nerve injury?
|
foot drop
|
|
|
How is a L5 radiculopathy distinguished from a common peroneal nerve injury in terms of foot weakness?
|
L5 radic has weakness in ankle dorsiflexors, ankle evertors AND ankle invertors
Common peroneal nerve injury is just weakness of the ankle dorsiflexors and ankel evertors |
|
|
What are the 5 differential diagnoses of foot drop?
|
polyneuropathy - diabetes
common peroneal neuropathy plexopathy radiculopathy -L4/5 central - tumor, CVA, AVM, SCI |
|
|
What are the sensory NCS EDX findings in common peroneal neuropathy?
|
abnormal superfical peroneal SNAP
|
|
|
What is the motor NCS EDX finding in common peronal neuropathy?
|
abnormal peroneal nerve CMAP
|
|
|
What are the EMG EDX findings in common peroneal neuropathy?
|
abnormal activity in the muscles innervated by the superficial and deep peroneal nerves
|
|
|
What muscle is spared in common peroneal neuropathy and why?
|
short head of the biceps femoris
since it is innervated by the peroneal DIVISION of the sciatic nerve (before it branches) |
|
|
With what is a deep peroneal neuropathy associated?
|
anterior tarsal tunnel syndrome
|
|
|
What type of shoes can cause a deep peroneal neuropathy?
|
high heeled
|
|
|
Where is the deep peroneal nerve injured typically?
|
as it passes under the extensor retinaculum
|
|
|
High heeled shoes can cause what type of neuropathy?
|
deep peroneal neuropathy
|
|
|
What muscle can atrophy in a deep peroneal neuropathy?
|
extensor digitorum brevis
|
|
|
Atrophy of the EDB is usually caused by what neuropathy?
|
deep peroneal neuropathy
|
|
|
Where are the sensory deficits in deep peroneal neuropathy?
|
1st and 2nd web spaces
|
|
|
What is the sensory NCS EDX finding in deep peroneal neuropathy?
|
abnormal findings in the 1st web space
|
|
|
What is the motor NCS EDX finding in deep peroneal neuropathy?
|
abnormal findings in the EDB
|
|
|
Motor NCS of abnormal EDB and abnormal sensory NCS of 1st web space indicates what neuropathy?
|
deep peroneal neuropathy
|
|
|
What are the EMG EDX findings in deep peroneal neuropathy?
|
abnormal activity in deep peroneal innervated muscles
|
|
|
What 2 muscles are innervated by the superficial peroneus nerve?
|
peroneus longus and brevis
|
|
|
What is the nature (sensory or motor) of the nerve continuation from the superficial peroneal nerve?
|
pure sensory
|
|
|
What muscles are affected if the injury to the superficial peroneal nerve is proximal to the ankle?
|
peroneal longus and brevis
|
|
|
What is the sensory NCS EDX finding in superficial peroneal neuropahty?
|
abnormal superficial peroneal nerve SNAP
|
|
|
What are the EMG/NCS findings if the superficial peroneal nerve lesion is distal to the ankle?
|
normal peroneus longus and brevis activity
|
|
|
What are the two peripheral nerve contributors to the sural nerve?
|
tibial and common peroneal
|
|
|
What the two sensory distributions of the sural nerve?
|
lateral calf and foot
|
|
|
What is the nature of the sural nerve (sensory, motor, or both)?
|
pure sensory
|
|
|
The sural nerve travel next to what malleolus?
|
lateral
|
|
|
What type of cyst can cause a sural neuropathy?
|
Baker's cyst
|
|
|
Wearing tight socks can cause what type of neuropathy?
|
sural neuropathy
|
|
|
What is the sensory NCS EDX finding in sural neuropathy?
|
abnormal sural SNAP
|
|
|
What two structures can be affected by a peripheral neuropathy?
|
myelin
axon |
|
|
Extensive demyelination can affect what nerve structure?
|
axon
|
|
|
What is the pattern of peripheral neuropathy that involves all nerves in a length dependant fashion to a relatively equal extent?
|
diffuse
|
|
|
What is the pattern of a peripheral neuropathy that involves one or multiple nerves in an asymmetric or patchy distribution?
|
multifocal
|
|
|
What is usually more affected in a peripheral neuropathy, upper or lower limbs?
|
lower
|
|
|
How many limbs must be evaluated in a peripheral neuropathy EDX?
|
3
|
|
|
What are 4 NCS abnormal findings in a demyelinating injury?
|
*prolonged distal latency
*slowed conduction velocity *conduction block *increased temporal dispersion |
|
|
What are 3 EMG findings in a demyelinating injury?
|
*no fibs or psws
*myokimic discharge *decreased recruitment |
|
|
What are 2 normal and 2 NCS abnormal findings in an axonal injury?
|
*normal distal latency
*normal conduction velocity *reduced CMAP amplitude *reduced SNAP amplitude |
|
|
What two categories of neurological conditions will not be detected with conventional NCS?
|
small fiber
autonomic dysfunction |
|
|
The etiology of what symptoms will not be detected using conventional NCS?
|
BP changes
dry skin dry eyes dry mouth |
|
|
Unmyelinated sympathetic nerve fibers are evaluated using what method?
|
sympathetic skin response
|
|
|
What are the stimuli used for sympathetic median nerve testing?
|
electrical, coughing, noises, breathing, tactile
|
|
|
In autonomic nerve testing how are stimuli applied? and why?
|
irregularly, to prevent nerve habituation
|
|
|
Normal heart rate variation is dependent on what nervous system?
|
parasympathetic
|
|
|
Loss of normal sinus arrthymia represents what pathological process?
|
dennervation
|
|
|
What ratio is measured during a cardiovagal innervation study?
|
R-R ratio
|
|
|
What phases are measured during a valsalva maneuver done during a cardiovagal innervation study?
|
Phase 2 and Phase 4
|
|
|
What is the expected heart rate finding in phase 2? (increase or decrease)
|
increase in heart rate
|
|
|
What is the expected heart rate response in phase 4, during valsalva during a cardiovagal innervation study?increase or decrease?
|
decrease
|
|
|
HMSN-I, HMSN-II, HMSN-IV, and leukodystrophy are what type of peripheral neuropathies?
|
demyelinating uniform sensorimotor
|
|
|
Name 4 uniform senorimotor demyelinating peripheral neuropathies.
|
HMSN-I, HMSN-II, HMSN-IV, and leukodystrophy
|
|
|
AIDP, CIDP, arsenic, toxins, monoclonal gammopathy, diptheria, AIDs, leprosy, and lyme disease are etiologies of what type of peripheral neuropathy?
|
motor>sensory segmental demyelinating
|
|
|
What are 9 etiologies of motor>sensory segmental demyelinating peripheral neuropathy>
|
AIDP, CIDP, arsenic, toxins, monoclonal gammopathy, diptheria, AIDs, leprosy, and lyme disease
|
|
|
Diabetes and uremia are etiologies of what type of peripheral neuropathy?
|
sensorimotor demyelinating/axonal
|
|
|
What are two etilogies of sensorimotor demyelinating/axonal peripheral neuropathy?
|
diabetes
uremia |
|
|
Porphyria, vincristine, lead, AIDP, dapsone, and HMSN-II are all etiologies of what type of periperhal neuropathy?
|
motor>sensory axonal
|
|
|
What are 6 etiologies of motor>sensory axonal loss?
|
Porphyria, vincristine, lead, AIDP, dapsone, and HMSN-II
|
|
|
Cis-platinum, Freidreich's ataxia, HSN, Sjogren's syndrome, pryidoxine, and Crohn's disease are all etiologies of what type of peripheral neuropathy?
|
sensory axonal loss
|
|
|
Diabetes and uremia are etiologies of what type of peripheral neuropathy?
|
sensorimotor demyelinating/axonal
|
|
|
What are two etilogies of sensorimotor demyelinating/axonal peripheral neuropathy?
|
diabetes
uremia |
|
|
Porphyria, vincristine, lead, AIDP, dapsone, and HMSN-II are all etiologies of what type of periperhal neuropathy?
|
motor>sensory axonal
|
|
|
What are 6 etiologies of motor>sensory axonal loss?
|
Porphyria, vincristine, lead, AIDP, dapsone, and HMSN-II
|
|
|
Cis-platinum, Freidreich's ataxia, HSN, Sjogren's syndrome, pryidoxine, and Crohn's disease are all etiologies of what type of peripheral neuropathy?
|
sensory axonal loss
|
|
|
What are 5 etiologies of sensory axonal loss peripheral neuropathy?
|
Cis-platinum
Freidreich's axtaxia HSN Sjogren's syndrome pyridoxine Crohn's disease |
|
|
Amyloidosis, etoh, vitamin B-12, folate, toxins, gold, mercury, paraneoplastic syndrome, sarcoidosis, lyme disease, and HIV-related are etiologies of what type of peripheral neuropathy?
|
sensorimotor axonal loss
|
|
|
Name 11 etiologies of sensorimotor axonal loss peripheral neuropathy.
|
Amyloidosis, etoh, vitamin B-12, folate, toxins, gold, mercury, paraneoplastic syndrome, sarcoidosis, lyme disease, and HIV-related
|
|
|
What are the 4 classifications used in classification II?
|
*diffuse axonal polyneuropathy
*multifocal axonal neuropathy *diffuse demyelinating polyneuropathy *multifocal demyelinating neuropathy |
|
|
What is a toxin etiology of diffuse axonal polyneuropathy?
|
heavy metals
|
|
|
What are two drug causes of diffuse axonal polyneuropathy?
|
vincristine, etoh
|
|
|
What is a deficiency etiology of diffuse axonal polyneuropathy?
|
vitamin B6
|
|
|
What are 3 metabolic causes of diffuse axonal polyneuropathy?
|
uremia, diabetes, paraneoplastic syndrome
|
|
|
What is a hereditary cause of diffuse axonal polyneuropathy?
|
HMSN-II
|
|
|
What are two infectious causes of diffuse axonal polyneuropathy?
|
lyme's disease and HIV
|
|
|
What are 5 etiologies of sensory axonal loss peripheral neuropathy?
|
Cis-platinum
Freidreich's axtaxia HSN Sjogren's syndrome pyridoxine Crohn's disease |
|
|
Amyloidosis, etoh, vitamin B-12, folate, toxins, gold, mercury, paraneoplastic syndrome, sarcoidosis, lyme disease, and HIV-related are etiologies of what type of peripheral neuropathy?
|
sensorimotor axonal loss
|
|
|
Name 11 etiologies of sensorimotor axonal loss peripheral neuropathy.
|
Amyloidosis, etoh, vitamin B-12, folate, toxins, gold, mercury, paraneoplastic syndrome, sarcoidosis, lyme disease, and HIV-related
|
|
|
What are the 4 classifications used in classification II?
|
*diffuse axonal polyneuropathy
*multifocal axonal neuropathy *diffuse demyelinating polyneuropathy *multifocal demyelinating neuropathy |
|
|
What is a toxin etiology of diffuse axonal polyneuropathy?
|
heavy metals
|
|
|
What are 4 microangiopathic causes of multifocal axonal neuropathy?
|
vasculitis
diabetes amyloidosis paraneoplastic syndrome |
|
|
What is an infectious cause of multifocal axonal neuropathy?
|
CMV
|
|
|
What are two metabolic causes of multifocal axonal neuropathy?
|
porphyria, compression
|
|
|
What are two hereditary causes of diffuse demyelinating polyneuropathy?
|
HMSN-I
HMSN-IV |
|
|
What is a deficiency cause of diffuse demyelinating polyneuropathy?
|
hypothyroidism
|
|
|
What are two toxic/drug causes of diffuse demyelinating polyneuropathy?
|
arsenic/amiodarone
|
|
|
What are two autoimmune causes of multifocal demyelinating neuropathy?
|
AIDP
CIDP |
|
|
What is an infectious cause of multifocal demyelinating neuropathy?
|
leprosy
|
|
|
What is the inheritance pattern of charcot marie tooth?
|
autosomal dominant
|
|
|
When is the onset of CMT?
|
early childhood
|
|
|
What is the gait pattern of CMT?
|
steppage
|
|
|
What is the leg appearance of CMT?
|
stork leg
|
|
|
What nerve is hypertrophied in CMT?
|
greater auricular nerve
|
|
|
What syndrome is associated with CMT?
|
Roussy-Levy syndrome
|
|
|
What is the steppage gait caused by in CMT?
|
bilateral foot drop
|
|
|
What CSF abnormality is present in CMT?
|
increased protein
|
|
|
In what condition is onion bulb formation seen?
|
CMT
|
|
|
What is CMT also called?
|
HMSN-I
|
|
|
Where is sensory loss more apparent in CMT? upper or lower limbs?
|
lower
|
|
|
What two senses are abnormal in CMT?
|
propioception and vibration
|
|
|
What is a prominent motor NCS EDX finding in HMSN-I (CMT)?
|
70% decrease in CV
|
|
|
What is the EMG EDX finding in CMT?
|
normal
|
|
|
What 2 findings are normal and absent in motor NCS EDX in CMT?
|
no temporal dispersion
no conduction block |
|
|
What is another name for HMSN III?
|
Dejerine Sottas
|
|
|
When is the onset of HMSN III?
|
birth/infancy
|
|
|
What 3 foot changes are apparent in HMSN I?
|
pes cavus
hammer toes intrinsic atrophy |
|
|
What foot change is present in HMSN III?
|
pes cavus
|
|
|
What is the patient's muscle tonicity in HMSN II?
|
hypotonic/floppy baby
|
|
|
What eye and hearing problems do HMSN III have?
|
nystagmus/deaf
|
|
|
What spine problem is present in HMSN III?
|
kyphoscoliosis
|
|
|
What is present in CSF in HMSN III?
|
increased protein
|
|
|
What is the EMG EDX of HMSN III?
|
normal
|
|
|
What are two prominent motor NCS EDX findings of HMSN III in terms of CV and latency?
|
CV<6m/sec
latency is 7x slower than normal |
|
|
What is another name for HMSN IV?
|
Refsum's disease
|
|
|
What is the inheritence pattern of HMSN IV?
|
autosomal recessive
|
|
|
When is onset in HMSN IV?
|
3rd decade
|
|
|
What is the gait pattern of HMSN IV?
|
steppage
|
|
|
What muscles atrophy in HMSN IV?
|
lower extremities
|
|
|
What is another name for Refsum's disease?
|
HMSN IV
|
|
|
What is the inheritance pattern of HMSN IV?
|
autosomal recessive
|
|
|
What type of neuropathy does HMSN IV cause?
|
uniform demyelinating sensorimotor
|
|
|
What type of neuropathy does HMSN III cause?
|
uniform demyelinating sensorimotor
|
|
|
What type of neuropathy does CMT or HMSN I cause?
|
uniform demyelinating sensorimotor
|
|
|
What is the gait of HMSN IV?
|
steppage
|
|
|
What are the 2 visual and 1 auditory deficits in HMSN IV?
|
retinitis pigmentosa/cataracts and deafness
|
|
|
What area of body atrophies in HMSN IV?
|
lower extremities
|
|
|
When is the onset of HMSN IV?
|
3rd decade
|
|
|
What are the CSF findings in HMSN IV?
|
increased protein
|
|
|
What does a nerve biopsy show in HMSN IV?
|
onion bulb formation
|
|
|
What blood test is high in HMSN IV?
|
phytanic acid
|
|
|
What are the 2 motor NCS EDX findings in HMSN IV?
|
CMAP abnormal
CV 10 m/sec |
|
|
What is AIDP?
|
acute inflammatory demyelinating polyradiculopathy
|
|
|
What type of neurpathy is AIDP?
|
segmental demyelinating motor and sensory
|
|
|
What is the time frame of AIDP?
|
1-4 weeks after insult (i.e. surgery, viral illness, etc.)
|
|
|
What is another name for AIDP?
|
guillan bare syndrome
|
|
|
What is first sign of AIDP?
|
ascending numbeness
|
|
|
What are most common CN affected in AIDP?
|
CN VII
|
|
|
What CNs are not affected by AIDP?
|
CN I and II
|
|
|
What is the motor involvement in AIDP?
|
ascending weakness
|
|
|
What does CSF show in AIDP?
|
increased protein
|
|
|
What is first EDX sign of AIDP?
|
Abnormal F wave
|
|
|
What does the CMAP show in AIDP?
|
abnormal -temporal dispersion
|
|
|
What does EMG EDX show in AIDP?
|
normal
|
|
|
What parameters of the CMAP, F-wave, and EMG indicate a poor prognosis is AIDP?
|
*CMAP - amplitude <20% of normal; CV <40% of normal
*F-wave - absent * EMG - abnormal activity (axonal involvment |
|
|
What are 2 treatments for AIDP?
|
plasmapheresis
immunoglobulins |
|
|
What is CIDP?
|
chronic inflammatory demyelinating polyradiculopathy
|
|
|
What type of neuropathy is CIDP?
|
segmental demyelinating motor and sensory
|
|
|
What is the peak age range for CIDP?
|
50-60
|
|
|
What is the characterization of the course of CIDP?
|
relapsing remitting
|
|
|
What is the weakness pattern in CIDP? (i.e. asymmetric vs symmetric; proximal vs distal)
|
symmetrical
proximal>distal |
|
|
What does the CSF show in CIDP?
|
increased protein
|
|
|
What is the mainstay of treatment for CIDP?
|
high dose steroids
|
|
|
What is the prognosis for CIDP?
|
good
|
|
|
What is the main motor NCS EDX finding in CIDP?
|
abnormal CMAP
increased temporal dispersion |
|
|
What is the cause of leprosy?
|
mycobacterium leprae
|
|
|
What is another name for leprosy?
|
hansen's disease
|
|
|
What is the most common casue of neuropathy worldwide?
|
Leprosy
|
|
|
What type of neuropathy does leprosy cause?
|
segmental demyelinating motor and sensory
|
|
|
What anatomic "drops" are common in leprosy?
|
foot and wrist drop
|
|
|
What palsy is common in leprosy?
|
facial palsy
|
|
|
What are the findings of a nerve biopsy in leprosy?
|
foamy histocyte invasion
|
|
|
What is the treatment for leprosy?
|
dapsone
|
|
|
What are the motor and sensory NCS findings in leprosy?
|
abnormal SNAP and CMAP
|
|
|
What type of neuropathy is caused by porphyria?
|
axonal motor>sensory
|
|
|
Where is the pain in porphyria?
|
lower extremities
|
|
|
Where is the weakness in porphyria?
|
all limbs
|
|
|
What is color of urine in porphyria?
|
deep red
|
|
|
What neurological emergency happens in porphyria?
|
seizures
|
|
|
To what medicines are patients with porphyria sensitive?
|
barbiturates
sulfonimides |
|
|
What are the motor and sensory NCS EDX findings in porphyria?
|
abnormal SNAP and CMAP
|
|
|
What 3 toxins (1 heavy metal and 2 meds) can cause a axonal motor>sensory neuropathy?
|
lead
vincristine dapsone |
|
|
What type of neuropathy can lead, vincristine and dapsone cause?
|
axonal motor>sensory
|
|
|
Where is the weakness in lead?
|
progressive UE weakness
|
|
|
What type of mononeuropathy can lead cause? leading to what joint "drop"?
|
radial neuropathy
wrist drop |
|
|
What are the dental findings in lead toxicity?
|
blue lines in gums
|
|
|
What brain pathology can lead toxicity cause in children?
|
encephalopathy
|
|
|
What are red blood cell findings in lead toxicity?
|
basophilic stippling in RBCs
|
|
|
What do xrays show in lead toxicity?
|
lead lines
|
|
|
What does the EMG show in lead toxicity?
|
abnormal radial muscles
|
|
|
What is the pharma treatment of lead toxicity?
|
penicillamine
EDTA |
|
|
What type of neuropathy can vincristine cause?
|
axonal motor>sensory
|
|
|
Where are the paresthesias and weakness in vincristine toxicity?
|
lower extremities
|
|
|
What are the sensory and motor NCS and EMG findings in vincristine toxicity?
|
all abnormal
|
|
|
What does dapsone treat?
|
leprosy
|
|
|
What type of neuropathy can dapsone cause?
|
axonal motor>sensory
|
|
|
What is the direction (i.e.descending or ascending) of dapsone neuropathy?
|
ascending
|
|
|
What type of globulinemia can dapsone cause?
|
methomoglobulinemia
|
|
|
What is the sensory NCS EDX finding in dapsone neuropathy?
|
normal
|
|
|
What is the motor NCS EDX finding in dapsone toxicity?
|
abnormal
|
|
|
What is the EMG EDX finding in dapsone toxicity?
|
abnormal activity
|
|
|
Axonal involvement of AIDP causes what type of neuropathy?
|
axonal motor>sensory
|
|
|
With what infective organisms is AIDP axonal associated?
|
CMV
C. jejuni |
|
|
What is the reflex finding in axonal AIDP?
|
areflexia
|
|
|
What are the sensory, motor, and EMG EDX findings in AIDP axonal?
|
abnormal
|
|
|
What is the CSF finding in AIDP axonal?
|
increased protein
|
|
|
CMV and C. jejuni are associated with what disease?
|
AIDP axonal
|
|
|
What is the inheritence pattern of HMSN II?
|
autosomal dominant
|
|
|
When is the onset in HMSN II?
|
2nd decade
|
|
|
What are two neurological symptoms in HMSN II?
|
ataxia
tremors |
|
|
Is there onion bulb formation in nerve biopsy in HMSN II?
|
no
|
|
|
What is the CV in HMSN II?
|
normal
|
|
|
In what muscles is there abnormal activity in HMSN II?
|
paraspinals
|
|
|
What is the motor NCS EDX finding in HMSN II?
|
abnormal
|
|
|
What is another name for HMSN II?
|
Charcot Marie Tooth II
|
|
|
What type of neuropathy does Cis platinum cause?
|
axonal sensory
|
|
|
Where are the paresthesias in cis platinum toxicity?
|
hands and feet
|
|
|
What are 4 side effects of cis platinum treatment?
|
nephrotoxicity
ototoxicity myelosuppression GI complaints |
|
|
What does the nerve bx show in cis-platinum toxicity?
|
abnormal large axons
|
|
|
What is the CMAP in cis platinum toxicity?
|
normal
|
|
|
What is the EMG in cis platinum toxicity?
|
normal
|
|
|
What is the SNAP in cis platinum toxicity?
|
abnormal
|
|
|
What is the inheritance pattern of Friedreich's ataxia?
|
autosomal recessive
|
|
|
What is the age range of onset of Friedreich's ataxia?
|
2-16
|
|
|
What is the optic finding in Friedreich's?
|
optic atrophy
|
|
|
What is the foot finding in Friedreich's?
|
pes cavus deformity
|
|
|
What is the spine finding Friedreich's ataxia?
|
kyphoscoliosis
|
|
|
What is the cardiac finding in Friedreich's ataxia?
|
cardiomyopathy
|
|
|
Where is the ataxia in Friedreich's ataxia?
|
limb and trunk
|
|
|
What is the SNAP in Friedreich's?
|
abnormal SNAP
|
|
|
What is the CMAP and Friedreich's?
|
normal
|
|
|
What is the nerve bx finding in Friedreich's?
|
abnormal activity
|
|
|
What is the cause of abnormal EMG activity in Friedreich's?
|
motor unity remodeling
|
|
|
What type of neuropathy is caused by Sjogren's syndrome?
|
axonal sensory
|
|
|
What are the 3 hallmark symptoms of Sjogren's?
|
dry eyes
dry mouth keratoconjunctivitis |
|
|
With what other autoimmune disorder is Sjogren's associated?
|
RA
|
|
|
What does the nerve bx show in Sjogren's?
|
abnormal large axons
|
|
|
What is the SNAP in Sjogren's?
|
abnormal
|
|
|
What is the cause of the abnormal EMG activity in Sjogren's?
|
muscle remodeling
|
|
|
What type of neuropathy is caused by pyridoxine (B6)?
|
axonal sensory
|
|
|
What sign is positive in B6 toxicity?
|
Lhermitte's sign
|
|
|
Above what daily dose can B6 become toxic?
|
>600mg/day
|
|
|
What are two hallmark symptoms of B6 toxicity?
|
abnormal sensation
gait disturbance |
|
|
What does the nerve bx show in B6 toxicity?
|
abnormal large and small axons
|
|
|
What is the motor NCS EDX finding in B6 toxicity?
|
normal
|
|
|
What is the sensory NCS EDX finding in B6 toxicity?
|
abnormal SNAP
|
|
|
What does the EMG show in B6 toxicity?
|
abnormal: occ fibs and PSWs
|
|
|
What is the treatment for B6 toxicity?
|
stop B6
|
|
|
What type of neuropathy does ETOH cause?
|
axonal sensorimotor
|
|
|
What anatomic "drops" occur with ETOH toxicity?
|
foot or wrist drops
|
|
|
What type of psychosis is caused by ETOH toxicity?
|
Korsakoff's psychosis
|
|
|
What type of encephalopathy is caused by ETOH toxicity?
|
Wernicke's encephalopathy
|
|
|
What does the nerve bx show in ETOH toxicity?
|
wallerian degeneration
|
|
|
What do the motor and sensory NCS and EMG EDX findings show in ETOH toxicity?
|
abnormal
|
|
|
What type of neuropathy does amyloidosis cause?
|
axonal sensorimotor
|
|
|
What constitutional change does amyloidosis cause?
|
weight loss
|
|
|
What liver condition is caused by amyloidosis?
|
hepatomegaly
|
|
|
What cardiac condition is caused by amyloidosis?
|
CHG
|
|
|
Where does edema occur in amyloidosis?
|
ankle
|
|
|
What renal condition can be caused by amyloidosis?
|
nephrotic syndrome
|
|
|
What are the motor and sensory NCS and EMG EDX findings in amyloidosis?
|
all normal
|
|
|
What does the tissue bx show in amyloidosis?
|
+birefrigence with Congo red
|
|
|
What type of neuropathy is caused by sarcoidosis?
|
axonal sensorimotor
|
|
|
What CN is most commonly involved with sarcoidosis?
|
CN VII
|
|
|
What is constitutional finding in sarcoidosis in infants?
|
low birth weight
|
|
|
What is the distribution (unilateral or bilateral) and where is the adenopathy in sarcoidosis?
|
bilateral hilar
|
|
|
What is an eye finding in sarcoidosis?
|
uveitis
|
|
|
What does the nerve bx show in sarcoidosis?
|
sarcoid tubercles
|
|
|
What do the sensory and motor NCS and EMG EDX finding show in sacroidosis?"
|
all abnormal
|
|
|
What type of neuropahty does DM cause?
|
sensorimotor axonal and demyelinating
|
|
|
What is the most common cause of peripheral neuropathy in North America?
|
diabetes
|
|
|
What are the nerve bx findings in DM?
|
small and large fiber abnormalities
|
|
|
What are the motor and sensory NCS and EMG EDX findings in DM?
|
all abnormal
|
|
|
What occurs in 60% of patients with renal failure?
|
uremia
|
|
|
What type of neuropathy is caused by uremia?
|
sensorimotor axonal demyelinating
|
|
|
With what condition is uremia associated (other than renal failure)
|
restless leg syndrome
|
|
|
What a unique sensory symptom in uremia toxicity?
|
hypersensitivity to touch
|
|
|
What does the nerve bx show in uremia?
|
paranodal demyelination and axon loss
|
|
|
What are the sensory and motor NCS and EMG EDX findings in uremia?
|
all abnormal
|
|
|
What are two treatments for uremia?
|
dialysis
renal transplant |
|
|
What is the most common type of HIV associated neuropathy?
|
distal symmetric polyneuropathy
|
|
|
What and where are the first symptoms in HIV distal symmetric polyneuropathy? How do they advance
|
painful toe paresthesias followed by the fingers and advancing proximally
|
|
|
What distinguishes HIV associated inflammatory demyelinating polyneuropathy from that seen in AIDP/CIDP?
|
pleocytosis in the CSF with increased protein
|
|
|
What 2 fibers does distal symmetric polyneuropathy affect in HIV?
|
sensory and autonomic
|
|
|
What is the HIV associated mononeuropathy?
|
mononeuropathy multiplex
|
|
|
Where is the vascular pathology in HIV mononeuropathy multiplex?
|
thrombosis of the vasa nervorum
|
|
|
What is the 2 nerve pathology finding in HIV mononeuropathy multiplex?
|
*axonal loss
*myelin sparing |
|
|
What is the EMG finding in HIV mononeuropathy multiplex?
|
abnormal spontaneous activity
|
|
|
What is the NCS findings in HIV mononeuropathy multiplex?
|
normal NCS wtih decreased amplitiudes
|
|
|
What HIV associated neuropathy is caused by a viral agent and what is that agent?
|
progressive polyradiculopathy
CMV |
|
|
What is the distribution (symmetric or asymmetric) and the 3 hallmark symptoms in HIV progressive polyradiculopathy?
|
asymmetric lower extremity pain, numbness, and weakness
|
|
|
What other severe constitutional symptoms are noted in HIV progressive polyradiculopathy?
|
bowel and bladder dysfunction
|
|
|
What is another HIV related neuropathy that affects BP, HR, digestion, etc.?
|
autonomic neuropathy
|
|
|
All HIV related neuropathies present with what nerve findings?
|
demyelination and axonal loss
|
|
|
Against which ACh receptors (pre- or post-synaptic) is the autoimmune response directed in myesthenia gravis?
|
post-synaptic
|
|
|
What amplitudes are reduced in MG?
|
mini endplate potential amplitudes
|
|
|
Is quantal content normal or decreased in MG?
|
normal
|
|
|
What syndrome has decreased quantal content, but normal quantal response?
|
Lambert-Eaton myasthenic syndrome
|
|
|
What syndrome has normal quantal content but decreased quantal response?
|
MG
|
|
|
Against what ACh receptors, (pre- or post-synaptic) is the autoimmune response directed in Lambert-Eaton?
|
pre-synaptic
|
|
|
MEPPs in Lambert show normal amplitudes but decreased what?
|
frequency
|
|
|
MG is associated with what disorder?
|
Thymic disorder or tumor
|
|
|
With what condition is LES associated?
|
small cell (oat cell) carcinoma of the cell
|
|
|
What is the male:female ratio in LEMS?
|
Male:Female 2:1
|
|
|
In LEMS what ion has decreased entry into the cell causing a decreased release of ACh into the synaptic cleft?
|
Ca++
|
|
|
Where is the defect in botulism, pre- or post-synaptic?
|
pre-synaptic
|
|
|
What is the causitive agent in botulism?
|
clostridium botulinum
|
|
|
What process does the clostridium botulinum toxin block?
|
exocytosis of ACh from the nerve terminal
|
|
|
What is the range of days after ingestion of the offending food that botulism develops?
|
2-7 days post ingestion
|
|
|
What muscles are affected first in MG, distal or proximal?
|
proximal
|
|
|
What 3 environmental factors exacerbate MG weakness?
|
exercise
heat evening |
|
|
Name 4 facial or bulbar MG symptoms?
|
ptosis
diplopia dysphagia dysarthria |
|
|
What activity improves MG weakness and fatigue?
|
rest
|
|
|
What test helps diagnose MG?
|
edrophonium (Tensilon) test
|
|
|
What is the edrophonium test?
|
2mg dose followed by a 8mg dose improves sxs in 1 minute
|
|
|
Muscle biopsy in MG shows loss of what?
|
loss of post-synaptic junctional folds and receptors
|
|
|
What does the SNAP show in MG?
|
normal
|
|
|
What does the CMAP show in MG with repetitive stim?
|
>10% decrement
|
|
|
What is the finding on EMG in MG?
|
unstable MUAP
|
|
|
Drop-off of unstable MUAPs in EMG in MG occurs under what condition?
|
sustained contraction
|
|
|
What is a surgical treatment for MG?
|
thymectomy
|
|
|
What is a pharma treatment for MG?
|
mestinon 30mg q4-6hours
|
|
|
What are two other medical treatments for MG?
|
steroids
immunosuppressive agents |
|
|
What modality can improve MG?
|
plasmapherisis
|
|
|
What fraction of patients with MG improve spontaneously?
|
1/3
|
|
|
Where is the weakness and fatigue in LEMS, proximal or distal?
|
proximal
|
|
|
Weakness and fatigue in what muscle is a hallmark of LEMS?
|
quads
|
|
|
What activity exacerbates LEMS?
|
rest
|
|
|
What activity improves LEMS?
|
exercise
|
|
|
What does muscle bx show in LEMS?
|
overdevelopment of NMJ, but with decreased active zones
|
|
|
What is the SNAP in LEMS?
|
normal
|
|
|
What is the CMAP amplitude in LEMS, increased or decreased?
|
decreased
|
|
|
EMG in LEMS shows what type of MUAP?
|
unstable
|
|
|
What activity provokes a drop-off in LEMS MUAP?
|
sustained contraction
|
|
|
What decrement (in %) is required for a dx of LEMs in motor repetitive stim NCS EDX?
|
10% decrement on repetitive stim
|
|
|
What pharma agent increases ACh quanta in LEMS?
|
guanidine increases ACh quanta
|
|
|
What are 3 possible side effects of guanidine tx?
|
GI
bone marrow suppression renal tubular necrosis |
|
|
What are the DTRs in botulism?
|
increased DTRs
|
|
|
What are 3 hallmark bulbar sxs in botulism?
|
ptosis
dysarthria dysphagia |
|
|
What happens to muscle tone in botulism?
|
widespread paralysis or flaccidity
|
|
|
In what lab specimens is botulinum toxin found?
|
blood and stool
|
|
|
What is the SNAP in botulism?
|
normal
|
|
|
What is the CMAP in botulism?
|
abnormal amplitude with >10% decrement with repetitive stime
|
|
|
What is the status of the MUAP on EMG in botulism?
|
unstable MUAP
|
|
|
What is the treatment for botulism?
|
trivalent ABE antitoxin
|
|
|
Nerve damage recovery from botulism comes from what nerve phenomenon?
|
collateral sprouting
|
|
|
What is the order, distal to proximal of muscles tested in repetitive nerve stim?
|
APB or ADM
deltoid trapezius orbicularis oculi |
|
|
What is considered an abnormality in repetitive nerves stimulation.
|
10% decrease in amplitude from 1st to 5th waveform
|
|
|
What is the description of a MUAP in MG?
|
unstable MUAP with varying amplitudes
|
|
|
At what Hz is low rate repetitive nerve stim conducted?
|
2-3 Hz
|
|
|
What is the repetitive nerve stim criteria for MG, LEMS, and botulism?
|
>10% decrement in amplitude
|
|
|
What type of muscle contratction and for how long is voluntarily performed after low rate repetitive stim? What is this called?
|
ismetric, 10 seconds; post activation facilitation
|
|
|
What does post activation facilitation demonstrate?
|
repair in CMAP amplitude
|
|
|
How is post activation exhaustion seen?
|
CMAP amplitude decrease
|
|
|
Between what two times is post activation exhaustion greatest?
|
between 2 and 4 minutes
|
|
|
What test should be used if repetitive stim decrement is not present initially?
|
post activation exhaustion
|
|
|
What is the Hz range from high rate repetitive stim?
|
10-50 Hz
|
|
|
What ion accumulates cells with high rate repetitive stim? And what does this ion facilitate?
|
Ca++; facilitates ACh release and repairs the waveform
|
|
|
Why is high rate repetitive stim performed?
|
when a patient is unable to perform maximal isometric contraction
|
|
|
What do the waveforms look like in LEMS with repetitive stim at rested, 2 min and 10 min?
|
nearly flatline
|
|
|
What is the amplitude change with high rate stime in LEMS?
|
200-300% increment
|
|
|
What is the amplitude change in MG with high rate stim?
|
decrement and partially repaired
|
|
|
What is the amplitude change in botulism with high rate stim?
|
mild increment
|
|
|
What two characteristics does pseudofaciliation demonstrate?
|
*progressive increase in CMAP amplitudes with voluntary contraction or high rate stim
*decrease in temporal dispersion |
|
|
Is pseudofacilitation normal or abnormal?
|
normal
|
|
|
In pseudofacilitation what happens to the area under the curve and why?
|
constant area eventhough the amplitude appears increased because the duration is decreased
|
|
|
Pseudofacilitation occurs in normal muscle because of what phenomenon?
|
increaseed synchronicity of muscle fiber contration
|
|
|
What technique is used if three muscles are normal with repetitive stim and an abnormal dx is still suspected?
|
single fiber emg
|
|
|
What is the most sensitive test for NMJ disorders?
|
single fiber emg
|
|
|
Is the specificity of single fiber high or low?
|
low specificity
|
|
|
What is a normal fiber density value?
|
1.5
|
|
|
A fiber density of >1.5 represents what process?
|
denervation and reinnervation process
|
|
|
What is a normal jitter value range in usec?
|
10-60 usec
|
|
|
Above what value is jitter considered abnormal?
|
>60 usec
|
|
|
What 4 conditions show increeased jitter?
|
ALS, NMJ disorders, axonal neuropathies and myopathies
|
|
|
What is the definition of jitter?
|
variation in interpotential discharges of two muscle fibers belonging to the same motor unit
|
|
|
What is increased jitter due to?
|
collateral sprouting
|
|
|
Immature neuromuscular junctions show increased jitter due to what phenomenon?
|
poor activation
|
|
|
What is blocking?
|
when a single MUAP fails to appear
|
|
|
At what jitter value (usec) does blocking appear?
|
>100 usec
|
|
|
In what time frame does blocking resolve?
|
1-3 months
|
|
|
Where is dystophin found?
|
protein found in sacrolemma a normal muscle
|
|
|
Duchenne's MD what is the deficiency?
|
dystrophin is absent or markedly deficiet
|
|
|
What is painless delayed relaxation of skeletal muscle following voluntary contraction?
|
myotonia
|
|
|
What environmental condition exacerbates myotonia?
|
cold
|
|
|
What three meds (or classes of meds) relieves myotonia?
|
dilantin
procainamide calcium channel blockers |
|
|
What does exercise do to myotonia, exacerbate it or relieve it?
|
relieves it
|
|
|
What is a fixed deformity of the extremities due to intrauterine hypomobility?
|
arthrogryposis
|
|
|
What is a hallmark sign of myopathy?
|
inability to generate a forceful contraction
|
|
|
What is the SNAP in myopathy?
|
normal
|
|
|
What are the motor CVs in myopathy?
|
normal
|
|
|
What is the CMAP abnormality in myopathy?
|
decreased amplitude
|
|
|
CRDs are seen in what 5 myopathies?
|
polymyositis
dermatomyositis muscular dystrophies Schwart Jampel syndrome inclusion body myopathy |
|
|
Polymyositis causes what 3 abnormal sponteous activity EMG findings?
|
CRDs
PSWs and FIBs myotonic discharges |
|
|
Dermatomyositis causes what 3 abnormal spontaneous activity EMG findings?
|
CRDs
PSWs and FIBs myotonic discharges |
|
|
Inclusion body myopathy causes what 2 EMG findings?
|
CRDs
PSWs and FIBs |
|
|
Muscular dystrophies cause what type of abnormal spont. activity?
|
CRDs
|
|
|
Schwartz-Jampel syndrome causes what type of abnormal sponateous activity on EMG?
|
CRDs
|
|
|
Trichinosis causes what type of abnormal spontaneous. activity?
|
FIBs and PSWs
|
|
|
Toxic myopathies cause what type of abnormal spontaneous activity?
|
FIBs and PSWs
|
|
|
Direct muscle trauma causes what type of abnormal spontaneous activity?
|
FIBs and PSWs
|
|
|
Rhabdomyolosis causes what type of abnormal spontaneous activity?
|
FIBs and PSWs
|
|
|
Acid maltase deficiency causes what 2 types of abnormal spontaneous activity?
|
FIBs and PSWs
myotonic discharges |
|
|
Myotubular myopathy causes what 2 types of abnormal spontaneous activity?
|
FIBs and PSWs
myotonic discharges |
|
|
Hyperkalemic periodic paralysis causes what 2 types of abnormal spontaneous activity?
|
FIBs and PSWs
myotonic discharges |
|
|
Nemaline rod causes what type of abnormal spontaneous activity?
|
FIBs and PSWs
|
|
|
Sarcoid myopathy causes what type of abnormal spontaneous activity?
|
FIBs and PSWs
|
|
|
Muscular dystophies cause what 2 types of abnormal spontaneous activity?
|
FIBs and PSWs
CRDs |
|
|
Myotonia congenita causes what type of abnormal spontaneous activity?
|
myotonic discharge
|
|
|
Myotonic dystrophy causes what type of abnormal spontaneous activity?
|
myotonic discharge
|
|
|
Paramyotonia congenita causes what type of abnormal spontaneous activity?
|
myotonic discharge
|
|
|
Hypothyroid myopathy causes what type of abnormal spontaneous activity?
|
myotonic discharge
|
|
|
Chloroquine myopathy causes what type of abnormal spontaneous activity?
|
myotonic discharge
|
|
|
Diazocholesterol intoxication causes what type of abnormal spontaneous activity?
|
myotonic discharge
|
|
|
What are classic polyphasic potentials due to loss of muscle fibers?
|
SDSA
|
|
|
What are polyphasic due to collateral sprouting?
|
LDLA
|
|
|
What are variable amplitude potentials due to blocking of immature neuromuscular junctions formed at the beginning of collateral sprouting.
|
Unstable
|
|
|
Quantitative EMG is better at what measure than regular EMG? What is this advantageous in diagnosing?
|
waveform duration; sensitive in diagnosing myopathies
|
|
|
How many MUAPs are used to calculate mean duration?
|
20 MUAPs
|
|
|
What three measures are demonstrated in single fiber EMG?
|
jitter
fiber density blocking |
|
|
What 3 conditions cause type I fiber atrophy?
|
myotonic dystrophy
nemaline rod myopathy fiber type disproportion |
|
|
What 3 conditions cause type II fiber atrophy?
|
steroid myopathy
MG decondtioning |
|
|
Deconditioning causes what type fiber atrophy?
|
type II atrophy
|
|
|
MG causes what type fiber atrophy?
|
Type II atrophy
|
|
|
Steroid myopathy causes what type fiber atrophy?
|
Type II atrophy
|
|
|
Myotonic dystrophy causes what type fiber atrophy?
|
Type I atrophy
|
|
|
Nemaline rod myopathy causes what type fiber atrophy?
|
Type I atrophy
|
|
|
What is the inheritence pattern of Duchenne MD?
|
x-linked recessive
|
|
|
On what allele is the Duchenne MD gene located?
|
xp21
|
|
|
What is the most common myopathy?
|
Duchenne's MD
|
|
|
When is onset age range for Duchenne MD?
|
3-5 years
|
|
|
What age range is death in Duchenne MD?
|
20s
|
|
|
Where does Duchenne MD weakness start
|
proximal - pelvic girdle
|
|
|
What is the classic walking pattern in Duchenne MD <5years old?
|
toe walking
|
|
|
What is Gower's sign?
|
difficulty rising from floor due to hip and knee extensor weakness
|
|
|
Where is the first and second contractures in Duchenne's MD?
|
ITB then achilles tendon
|
|
|
What muscle is subject to pseudohypertrophy in Duchenne's MD?
|
gastroc
|
|
|
What spine condition develops in Duchenne MD and leads to what 2 conditions?
|
scoliosis leads to cardiomyopathy and restrictive lung disease
|
|
|
When do patients Duchenne's MD usually start using wheelchairs?
|
12 years old
|
|
|
What muscles are spared in Duchenne's MD?
|
extraocular
|
|
|
What is absent in a Duchenne MD muscle bx?
|
dystrophin
|
|
|
What are 2 findings in Duchenne MD blood test?
|
increased CPK and aldolase
|
|
|
What is the SNAP in Duchenne MD?
|
normal SNAP
|
|
|
What are two findings in the EMG in Duchenne MD?
|
SDSA MUAP
early recruitment |
|
|
At what vital capacity (%) is scoliosis surgery performed in Duchenne MD?
|
<35% vital capacity
|
|
|
At what Cobb angle does VC usually go below 35%
|
cobb angle > 30 degress
|
|
|
What is the inheritenc pattern of Becker's MD?
|
x-linked recessive
|
|
|
When is the onset of Becker's MD?
|
adulthood
|
|
|
What are 3 hallmarks of Becker's MD? (similar to Duchenne's MD)
|
proximal weakness
calf pseudohypertrophy cardiomyopathy |
|
|
In what condition is mental retardation more common, DMD or Becker's MD?
|
DMD
|
|
|
What does the muscle bx show in Becker's MD?
|
decreased dystrophin
|
|
|
What are two EMG findings in Becker's MD?
|
early recruitment
SDSA MUAP |
|
|
What is the second most common myopathy?
|
Myotonic dystrophy
|
|
|
What is the inheritence pattern of myotonic dystrophy?
|
autosomal dominant
|
|
|
What age category is onset in myotonic dystrophy?
|
infant
|
|
|
What is the weakness pattern in myotonic dystrophy?"
|
distal>proximal
|
|
|
What facial muscles atrophy in myotonic dystrophy?
|
temporalis and masseter
|
|
|
In what condition does hypertrichosis and impotence occur?
|
myotonic dystrophy
|
|
|
Frontal balding is sx of what condition
|
myotonic dystrophy
|
|
|
What are three hallmark signs of myotonic dystrophy?
|
shark mouth
facial diplegia club foot |
|
|
Hatchet face occurs in what condition?
|
myotonic dystrophy
|
|
|
Myotonic dystrophy is also know as what condition?
|
Steinert's dystrophy
|
|
|
What type fiber atrophy and hypertrophy is present in myotonic dystrophy?
|
type I atrophy
type II hypertrophy |
|
|
What protein is normal in myotonic dystrophy?
|
dystrophin
|
|
|
What are 3 EMG findings in myotonic dystrophy?
|
early recruitment
SDSA MUAP myotonia |
|
|
What 3 meds are helpful in myotonic dystrophy?
|
procainamide
dilantin quinine |
|
|
What heat device may be necessary in myotonic dystrophy?
|
pacemaker
|
|
|
What is the mnemonic for meds useful in myotonic dystrophy?
|
PDQ
Procainamide Dilatin Quinine |
|
|
What is the inheritence pattern of fascioscapulohumeral (FSH)dystrophy?
|
autosomal dominant
|
|
|
What is the pattern on weakness in FSH?
|
proximal
|
|
|
Weak eye closing, facial droop, and forehead wrinkling are signs of what condition?
|
FSH
|
|
|
What muscles are spared in Popeye arm in FSH?
|
deltoid and forearm muscles
|
|
|
What are two ocular findings in FSH?
|
cataracts
retinopathy |
|
|
What protrudes in FSH?
|
lip
|
|
|
What is the formation of a smile in FSH?
|
transverse
|
|
|
What eye muscle is spared in FSH? (and 2 arm muscles)
|
extraocular as well as deltoid and forearm muscles are spared
|
|
|
What is the most important muscles to test in FSH?
|
tibialis anterior
|
|
|
What activity is a patient with FSH unable to perform?
|
whistle
|
|
|
What are 3 EMG findings in FSH?
|
abnormal activity
early recruitment SDSA MUAP |
|
|
What is the inheritence pattern of central core disease?
|
autosomal dominant
|
|
|
When is the onset of central core disease?
|
infancy
|
|
|
How is the infant with central core disease characterized?
|
floppy infant/hypotonia
|
|
|
What is the pattern of weakness in central core disease?
|
proximal
|
|
|
Congenital hip dislocation is a feature of what congenital myopathy?
|
central core disease
|
|
|
With what severe condition is central core disease associated?
|
malignant hyperthermia
|
|
|
What cellular component is absent in central core disease?
|
mitochondria
|
|
|
Central cores are found in what type fiber in central core disease?
|
type I fibers
|
|
|
What are 2 EMG findings in central core disease?
|
early recruitment
SDSA MUAP |
|
|
What is the inheritence pattern in nemaline rod myopathy?
|
autosomal dominant/recessive
|
|
|
When is onset in nemaline rod?
|
infancy
|
|
|
What is the cause of death in nemaline rod?
|
respiratory failure
|
|
|
What is the appearance of the face in nemaline rod?
|
narrowed long face
|
|
|
What "drop" is present in nemaline rod?
|
foot drop
|
|
|
What oral cavity finding is present in nemaline rod?
|
high arched palate
|
|
|
Rod shaped bodies on Gomori trichrome stain is present in what myopathy?
|
nemaline rod
|
|
|
What are two EMG findings in nemaline rod?
|
early recruitment
SDSA MUAP |
|
|
What is the tone of an infant with nemaline rod?
|
floppy infant/hyptonia
|
|
|
What is the inheritence pattern of centronuclear myotubular myopathy?
|
x-linked recessive
|
|
|
What is the tone of a baby with centronuclear myotubular myopathy?
|
floppy infant/hypotonia
|
|
|
What eye muscles are involved in centronuclear myotubular?
|
extra-ocular muscles are involved
|
|
|
What swallowing disorder is present in centronucleaer myotubular?
|
dysphagia
|
|
|
What is the facial appearance in centronuclear myotubular?
|
facial diplegia
|
|
|
What is the hallmark muscle biopsy finding in centronuclear myotubular?
|
central location of fiber nuclei, forming chains
|
|
|
What are 3 EMG findings in centronuclear myotubular?
|
abnormal activity
early recruitment SDSA MUAP |
|
|
When is onset in fiber type disproportion?
|
infancy
|
|
|
What is the tonicity in fiber type disproportion?
|
floppy infant/hyptonia
|
|
|
What are two hip findings in fiber type disproportion?
|
hip contractures
hip dislocations |
|
|
What is the characterization of type I and type II fibers on biopsy in fiber type disproportion?
|
small type I
large type II |
|
|
What are two EMG findings in fiber type disproportion myopathy?
|
early recruitment
SDSA MUAP |
|
|
Where is the initial then second area of weakness in polymyo/dermato?
|
hips followed by shoulders
|
|
|
In what condition is Gotton's sign found?
|
dermatomyo
|
|
|
What is Gottron's sign?
|
purple patches over knuckles, elbows, knees
|
|
|
Is facial or ocular weakness a symptom of polymyositis/dermato?
|
no facial or ocular weakness
|
|
|
What spinal flexion weakness is present in polymyo/dermato?
|
neck flexion weakness
|
|
|
What are two Gi/vocal symptoms are present in polymyo/dermato?
|
dysphagia
dysphonia |
|
|
What does the muscle bx show in polymyo/dermatomyo?
|
necrosis of type I and type II fibers
|
|
|
What are the SNAPs and CMAPs in polymyo/dermato?
|
both normal
|
|
|
What and where is the most prominent EMG finding in polymyo/dermato?
|
abnormal activity in paraspinals
|
|
|
What are two other EMG findings in polymyo/dermato?
|
early recruitment
SDSA MUAP |
|
|
What two classes of meds are helpful in polymyo/dermato?
|
steroids
cytotoxic agents |
|
|
What treatment modality is helpful in polymyo/dermatomyo?
|
plasmapherisis
|
|
|
In what myopathy are the LFTs abnormal?
|
polymyo/dermatomyo
|
|
|
What is the etiology of inclusion body?
|
unknown
|
|
|
Name 2 inflammatory myopathies?
|
polymyo/dermatomyo
inclusion body myositis |
|
|
Is the weakness in inclusion body symmetric or asymmetric?
|
asymmetric
|
|
|
With what neuro condition is inclusion body associated?
|
polyneuropathy
|
|
|
What does the blood test in inclusion body?
|
increased CK
|
|
|
What are two muscle bx findings in inclusion body?
|
*rimmed or cytoplasmic vacuoles
*eosinophilic inclusion bodies |
|
|
What are two definite EMG findings in inclusion body?
|
abnormal activity
early recruitment |
|
|
Name 2 metabolic myopathies.
|
McArdles's disease (type V)
Pompe's disease (type II) |
|
|
What is another name for McArdle's disease?
|
myophosphorylase deficiency
|
|
|
What is the inheritence pattern of McArdle's disease?
|
autosomal recessive
|
|
|
What is the age of onset of McArdle's disease?
|
<15 years old
|
|
|
What is a hallmark activity sign of McArdle's?
|
exercise intolerance
|
|
|
Strenuous exercise in McArdle's can precipitate what?
|
myolysis and cause renal failure and death
|
|
|
What improves symtoms in McArdle's?
|
brief rest after exercise improves symptoms - second wind phenomenon
|
|
|
What are the SNAPs and CMAPs in McArdle's?
|
normal
|
|
|
What is common muscle complaint in McArdle's?
|
cramping
|
|
|
What does the EMG show during an attack in McArdle's?
|
electrical silence due to sustained contracture
|
|
|
What does the urine show in McArdle's?
|
myoglobinuria
|
|
|
What are two mucsle bx findings in McArdle's?
|
excess glycogen
absent phosphorylase |
|
|
What is another name for Pompe's disease?
|
acid maltase deficiency
|
|
|
What 3 structures are enlarged in Pompe's
|
tongue
heart liver |
|
|
What is age of death in Pompe's?
|
2 years old
|
|
|
What are the SNAP and CMAP findings in Pompe's?
|
both normal
|
|
|
What are 3 EMG findings in Pompe's?
|
abnormal activity
early recruitment SDSA MUAP |
|
|
What blood value increase during an attack in Pompe's?
|
CK
|
|
|
What does the muscle bx show in Pompe's?
|
vacuoles in type I and type II fibers
|
|
|
What are two types of periodic paralysis?
|
hyperkalemic
hypokalemic |
|
|
What is the inheritence pattern of hyper and hypokalemic periodic paralysis?
|
autosomal dominant
|
|
|
What is the pattern of weakness in hyperkalemic?
|
proximal
|
|
|
Where are the paresthesias in hyperkalemic?
|
lips and lower limbs
|
|
|
What is the pattern of myotonia in hyperkalemic?
|
generalized myotonia
|
|
|
How can attacks be aborted in hyperkalemic?
|
exercise
|
|
|
What two environmental conditions/activity will exacerbate hyperkalemic?
|
cold exposure
rest following exercise |
|
|
How long does an attack last in hyperkalemic?
|
10-60 minutes
|
|
|
What the SNAP and CMAP findings in hyperkalemic?
|
both are normal
|
|
|
What are the 3 EMG findings during a hyperkalemic attack
|
abnormal activity
early recruitment SDSA MUAP |
|
|
What is a blood abnormality during an attack in hyperkalemic?
|
high blood K+
|
|
|
What is a dietary treatment for hyperkalemic?
|
high carbohydrate
|
|
|
What is the pattern of weakness in hypokalemic? Where does it start?
|
distal to proximal
starts in legs |
|
|
How long can attacks last in hypokalemic?
|
12-24 hours
|
|
|
Where is myotonia seen in hypokalemic?
|
eyelid myotonia
|
|
|
What diet exacerbates hypokalemic?
|
high carb
|
|
|
What activity exacerbates hypokalemic?
|
rest after exercise
|
|
|
What are the SNAP and CMAP findings in hypkalemic?
|
both are normal
|
|
|
What does the EMG show during an attack of hypokalemic?
|
electrical silence
|
|
|
What does the muscle bx show in hypokalemic?
|
normal
|
|
|
What dietary supplement is recommended in hypokalemic?
|
K+
|
|
|
What does the blood show in hypokalemic?
|
low K+
|
|
|
What is the inheritence pattern of myotonia congenita?
|
autosomal dominant
|
|
|
What environment condition exacerbates myotonia congenita?
|
cold
|
|
|
What is a muscle complaint in myotonia congenita?
|
spasms
|
|
|
Is there weakness in myotonia congenita?
|
no weakness
|
|
|
What is a muscle finding in myotonia congenita?
|
muscle hypertrophy
|
|
|
What alleviates spasm in myotonia congenita?
|
warmth and exercise
|
|
|
What are the SNAP and CMAP findings in myotonia congenita?
|
both are normal
|
|
|
What is the only EMG finding in myotonia congenita?
|
myotonic discharges
|
|
|
What 3 medications improve myotonia congenita? Mnemonic?
|
P procainamide
D dilantin Q quinine |
|
|
What are two other names for myotonia congenita?
|
Thompson's
Little Hercules |
|
|
What is the inheritence pattern of paramyotonia congenita?
|
autosomal dominant
|
|
|
What is another name for paramyotonia congenita?
|
Eulenberg
|
|
|
What is the primary muscle complaint in paramyotonia?
|
stiffness
|
|
|
What exacerbates paramyotonia?
|
cold and exercise
|
|
|
What does the muscle bx show in paramyotonia?
|
fiber size variation
|
|
|
What is the unique CMAP finding in paramyotonia?
|
CMAP is decreased with cooling
|
|
|
What is the SNAP in paramyotonia?
|
normal
|
|
|
What are the 2 possible EMG findings in paramyotonia?
|
electrical silence
abnormal activity with cooling |
|
|
What is the treatment for paramyotonia?
|
warm extremities
|
|
|
What is the pattern weakness in steroid myopathy?
|
proximal muscle weakness
|
|
|
What muscle fiber type atrophies in steroid myopathy?
|
type II
|
|
|
What are the SNAP and CMAP findings in steroid myopathy?
|
both are normal
|
|
|
What does the EMG show in steroid myopathy?
|
may be abnormal with small polyphasics in severe cases
|
|
|
What are two signs of motor neuron disease (MND)?
|
weakness
atrophy |
|
|
In what 3 locations may pathology be in MND?
|
spinal cord
brainstem motor cortex |
|
|
Name 3 lower motor neuron diseases.
|
spinal muscle atrophy
polio post polio syndrome |
|
|
Name one upper and lower motor neuron disease.
|
ALS
|
|
|
What are two signs of motor neuron disease (MND)?
|
weakness
atrophy |
|
|
Name on upper motor neuron disease.
|
Primary lateral scleroiss
|
|
|
In what 3 locations may pathology be in MND?
|
spinal cord
brainstem motor cortex |
|
|
Name 3 lower motor neuron diseases.
|
spinal muscle atrophy
polio post polio syndrome |
|
|
Name one upper and lower motor neuron disease.
|
ALS
|
|
|
Name on upper motor neuron disease.
|
Primary lateral scleroiss
|
|
|
Name 4 lower motor neuron signs.
|
atrophy
flaccidity hyporeflexia fasciculations |
|
|
Name 4 upper motor neuron signs.
|
weakness
spasticity hyperreflexia up-going plantar response |
|
|
What are SNAP and CMAP finding in MND?
|
both are normal, but CMAP may show decreased amplitude or CV
|
|
|
What 2 EMG findings are generally present in MND?
|
abnormal activity
decreased recruitment |
|
|
What is the EMG finding in SMA I?
|
FIBs and PSWs
|
|
|
What is the EMG finding in SMA II?
|
FIBs and PSWs
|
|
|
What are two EMG finding in SMA III?
|
FIBs PSWs
CRDs |
|
|
What is the EMG finding in ALS?
|
FIBs and PSWs
|
|
|
What are the two EMG findings in polio?
|
FIBs, PSWs
Fasciculations |
|
|
What MNDs have FIBs and PSWs?
|
SMA I
SMA II SMA III ALS Polio |
|
|
What is the EMG finding in post polio?
|
fasciculations
|
|
|
What MNDs cause fasciculations?
|
ALS
Polio post polio |
|
|
ALS can cause what two EMG findings?
|
FIBS PSWs
fasciculations |
|
|
CRDs are caused by what MND?
|
SMA III
|
|
|
What type of needle is used to sample the diaphragm?"
|
monopolor
|
|
|
Through what intercostal space is diaphragm sampling taken? at what vertical landmark?
|
8th or 9th intercostal space at the anterior axillary line
|
|
|
During inspiration or expiration do the intercostal muscles show a MUAP?
|
during expiration only
|
|
|
The diaphragm is recruited during what phase of breathing?
|
inspiration only
|
|
|
What MUAP amplitudes are larger, intercostals or diaphragm?
|
intercostals
|
|
|
What is another name for SMA I?
|
Werdnig-Hoffman
|
|
|
What is the inheritence pattern of Werdig Hoffman SMA I?
|
autosomal recessive
|
|
|
When is death by in Werdig Hoffman?
|
by age 3
|
|
|
Of all the SMAs what has the worst prognosis?
|
SMA I Werdig Hoffman
|
|
|
What muscles are affected least in Werdig Hoffman?
|
facial muscles
|
|
|
What milestone does a Werdig Hoffman baby never attain?
|
sitting independantly
|
|
|
In what oral structure are fasciculations present in SMA I?
|
tongue
|
|
|
What muscles are spared in SMA I?
|
sphincter and extra-ocular
|
|
|
What is the tonicity of a baby with Werdnig Hoffman?
|
floppy baby/hypotonia
|
|
|
What is the cry of a baby with Werdnig Hoffman?
|
weak cry
|
|
|
What does the muscle bx show in Werdnig Hoffman?
|
hypertrophy
atrophy |
|
|
What does the blood test show in Werdnig Hoffman?
|
increased CPK
|
|
|
What does the SNAP show in Werdnig Hoffman?
|
normal
|
|
|
What are three EMG findings in SMA I?
|
abnormal activity
LDLA/SDSA MUAP DR |
|
|
What is another name for SMA II?
|
chronci Werdnig Hoffman
|
|
|
What is the inheritence pattern of SMA II?
|
autosomal recessive
|
|
|
When is death in SMA II?
|
by age 10
|
|
|
When does wheelchair use start in SMA II/
|
by age 3
|
|
|
What is the usual cause of death in SMA I and II?
|
respiratory failure
|
|
|
What is the pattern of weakness in SMA II?
|
upper>lower
|
|
|
What is a spinal finding in SMA II?
|
kyphoscoliosis
|
|
|
What deformity of the feet is present in SMA II?
|
equinus deformity
|
|
|
What milestone does a SMA II baby acheive?
|
independant sitting
|
|
|
Can a SMA II child stand or walk without assistive device?
|
no
|
|
|
What does the blood test show in SMA II?
|
increased CPK
|
|
|
What does the muscle biopsy show in SMA II?
|
hypertrophy
atrophy |
|
|
What are the SNAP and CMAP findings in SMA I and II?
|
SNAP normal
CMAP +/- abnormal |
|
|
What are three EMG findings in SMA II?
|
abnormal activity
SDSA MUAP DR |
|
|
What is another name for SMA III?
|
Kugelberg-Welander
|
|
|
What is the inheritence pattern of SMA III?
|
autosomal recessive/dominant
|
|
|
What is the age range of onset in SMA III?
|
2-15 years
|
|
|
What is the life expectancy in SMA III?
|
normal
|
|
|
When is wheelchair use expected in SMA III?
|
by age 30
|
|
|
What is the pattern of weakness in SMA III? Upper or lower first
|
symmetric
upper then lower |
|
|
What are three hallmark signs/milestones in SMA III?
|
gowers sign
calf pseudohypertrophy independent standing/walking |
|
|
What are the SNAP and CMAP findings in SMA III?
|
both normal
|
|
|
What is the the blood finding in SMA III?
|
increased CPK
|
|
|
What is the muscle bx in SMA III?
|
hypertrophy
atrophy |
|
|
What are the SNAP and CMAP findings in SMA III?
|
both normal
|
|
|
What are 3 EMG findings in SMA III?
|
abnormal activity
LDLA/SDSA MUAP Dr |
|
|
What degenerates in ALS?
|
anterior horn cell
|
|
|
During what decade does ALS appear>
|
6th decade
|
|
|
What are 3 first signs of ALS?
|
*asymmetric atrophy
*weakness *fasciculations |
|
|
What are two oral signs of ALS?
|
dysphagia
dysarthria |
|
|
What stages of swallowing are affected in ALS?
|
oral
pharyngeal |
|
|
What 3 pseudobulbar signs are present in ALS?
|
difficulty chewing
difficulty swallowing unprovoked crying and laughing |
|
|
What functions are spared in ALS?
|
bowel and bladder sparing
extraocular muscle sparing |
|
|
What percentage of ALS patients die within 3 years?
|
50%
|
|
|
At what time frame after dx of ALS is wheelchair use usually indicated?
|
12-18 months
|
|
|
What are three predictors of survival in ALS?
|
younger age of onset
severity of onset pulmonary function |
|
|
What are the SNAP and CMAP findings in ALS?
|
both are normal
|
|
|
What are 4 EMG findings in ALS?
|
abnormal activity
DR LDLA MUAP CRDs |
|
|
What does single fiber EMG show in ALS?
|
increased jitter and fiber density
|
|
|
What is the EMG protocol in ALS?
|
abnormal activity in
2 muscles from 2 nerve roots in 3 body areas |
|
|
What medicine may be helpful in ALS?
|
riluzole
|
|
|
What slows disease progression?
|
anti-glutamate
|
|
|
What parameters of ALS does anti-glutamate affect negatively
|
prolongs ventilator time
prolongs BiPAP |
|
|
Where is the degeneration in polio?
|
anterior horn cell
|
|
|
What virus type causes polio?
|
picornavirus
|
|
|
Through what body system does picornavirus spread?
|
lymphatic system
|
|
|
What muscle fibers does polio affect?
|
orphaned muscle fibers
|
|
|
What is a prominent sign of polio?
|
weakness
|
|
|
What sense is spared in polio?
|
sensation
|
|
|
What percentage of patients completely recover?
|
50%
|
|
|
What bulbar palsies are present in polio?
|
dysphasia
nasal voice |
|
|
What percentage of patient with polio are severely disabled?
|
25%
|
|
|
What is the SNAP finding in polio?
|
normal SNAP
|
|
|
What is the CMAP finding in polio?
|
normal or decreased CMAP
|
|
|
What are 3 EMG findings in polio?
|
abnormal activity
D LDLA MUAP |
|
|
What is the pathology in post polio?
|
loss of anterior horn cell
|
|
|
What is the name of criteria for a dx of post polio?
|
Halstead Ross
|
|
|
What are the 5 Halstead Ross criteria in post polio?
|
*previous polio dx
*recovery of function *stable for 15 years *return of sxs *no other medical problems |
|
|
What are 6 hallmarks of post-polio?
|
*cold intolerance
*weakness *atrophy *fatigue *arthragia *myalgia |
|
|
What is the SNAP in post polio?
|
normal
|
|
|
What is the CMAP in post polio?
|
abnormal
|
|
|
What is a hallmark EMG finding in post-polio?
|
giant MUAP
|
|
|
What does low rate repetitive stim show in ALS?
|
increased decrement
|
|
|
What does low rate repetitive stim show in post polio?
|
normal
|
|
|
What 3 parameters are abnormal in single fiber EMG in post polio?
|
increased jitter
increased fiber density increased blocking |
|
|
On what basis is post-polio diagnosed, clinical presentation or EMG?
|
clinical presentation
|
|
|
What are 3 EMG findings in post polio?
|
abnormal activity
DR giant MUAP |
|
|
What are 5 parameters of systemic inflammatory response syndrome?
|
*body temp >38C or <36C
*HR >90 bpm *RR >20 breaths/min *PaCO2<32 torr *WBC >12,000 |
|
|
What 2 neuro conditions can occur in the setting of systemic inflammatory response syndrome?
|
critical illness polyneuropathy
critical illness myopathy |
|
|
What is the classification of critical illness polyneuropathy?
|
sensorimotor axonal/demyelinating
|
|
|
What is the myopathy classification of critical illness myopathy?
|
inflammatory myopathy
|
|
|
What is the etiology of both critical illness polyneuropathy and critical illness myopathy?
|
systemic inflammatory response syndrome
|
|
|
What are two clinical signs of critical illness neuropathy?
|
difficulty in weaning from vent
flaccid limbs |
|
|
What does muscle biopsy show in critical illness neuropathy?
|
denervation atrophy
|
|
|
What does EDX show in critical illness neuropathy?
|
axonal degeneration
motor and sensory |
|
|
What is the CK in critical illness neuropathy?
|
normal CK
|
|
|
What are two clinical signs of critical illness myopathy?
|
respiratory weakness
flaccid limbs |
|
|
What does muscle bx show in critical illness myopathy?
|
loss of thick filaments
|
|
|
What are two EMG findings in critical illness myopathy?
|
abnormal spontaneous activity
early recruitment |
|
|
What are 3 differential dxs in critical illness myopathy?
|
rhabdo
necrotizing myopathy disuse myopathy |
|
|
What are 4 differential dxs in critical illness polyneuropathy?
|
spinal cord compression
motor neuron disease GB MG myasthenic syndrome |
|
|
Is critical illness myopathy acute or gradual?
|
acute inflammatory
|
|
|
NCS latency in demyelination is prolonged or decreased?
|
prolonged
|
|
|
NCS velocity in demyelination is increased or decreased?
|
decreased
|
|
|
NCS temporal dispersion in demyelination is prolonged or decreased?
|
increased
|
|
|
NCS amplitude in demyelination is increased or decreased?
|
decreased
|
|
|
EMG insertional activity in demyelination is normal or abnormal?
|
normal
|
|
|
EMG resting activity in demyelination is increased, decereased, or normal?
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normal
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EMG recruitment in demyelination is increased, decreased, or normal?
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decreased
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EMG MUAP in demyelination is normal or abnormal?
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normal
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NCS latency in axonal injury in prolonged, decreased, or normal?
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normal
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NCS amplitude in axonal injury is increased, decreased or normal?
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decreased
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NCS temporal dispersion in an axonal injury is increased, decreased, or normal?
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normal
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NCS conduction velocity in temporal dispersion is increased, decreased, or normal?
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decreased
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EMG insertional activity in axonal injury is normal or abnormal?
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abnormal
|
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EMG resting activity in axonal injury is normal or abnormal?
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abnormal
|
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EMG recruitment in axonal injury is increased or decreased?
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decreased
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EMG MUAP in axonal injury is normal or abnormal?
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abnormal
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NCS amplitude in axonal regrowth is increased or decreased?
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decreased
|
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NCS duration is increased or decreasd in axonal regrowth?
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increased
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NCS waveform morphology is normal or polyphasic in axonal regrowth?
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polyphasic
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NCS latency is prolonged, decreased, or normal with a decrease in temperature?
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prolonged
|
|
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NCS amplitude is increased, decreased, or normal with a decrease in temperature?
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increased
|
|
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NCS duration is increased, decreased, or normal with a decrease in temperature?
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increased
|
|
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NCS conduction velocity is increased, decreased, or normal with a decrease in temperature?
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decreased
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What needle is more likely to pick up potentials from a remote motor unit, concentric or monopolar?
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monopolar
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What needle has a more stable baseline, a concentric or monopolar needle?
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concentric
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The sensitivity of a concentric needle is greatest at what hemispheric orientation of the needle?
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hemisphere facing the oblique elliptical surface
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What needle records larger MUAP amplitudes, concentric or monopolar?
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monopolar
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What two EMG characteristics show no difference between concentric and monopolar needles?
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duration and number of phases
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Why do monopolar needles record a larger amplitudes and durations than concentric needles?
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larger recording territory of a monopolar needle
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What is the effect of elevating the low frequency filter on peak latency prolongs, shortens, or same?
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shortens
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What is the effect of elevating the low frequency filter on amplitude, increases or decreases, or same?
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decreases
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What is the effect of elevating the low frequency filter on phase?
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biphasic to triphasic
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What is the effect of elevating the low frequency filter on onset latency, prolongs, shortens, or same?
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same
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What is the effect of lowering the high frequency filter on peak latency, prolongs, shortens, or same?
|
prolongs
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What is the effect of lowering the high frequency filter on amplitude increases, decreases, or same?
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decreases
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What is the effect of lowering the high frequency filter on negative spikes, increases, decreases, or same?
|
increases negative spike
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What is the effect of lowering the high frequency filter on onset latency, prolongs, shortens, or same?
|
prolongs
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|
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In infants, conduction velocity is correlated closely with what parameter?
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gestational age
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|
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What eyewear can abolish the blink reflex?
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contact lenses
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In what demographic is the blink reflex absent?
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infants under 9 months
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|
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Where is the brain's blinking center?
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globus pallidus of the basal ganglia
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What are the 3 CNs that can be tested with EMG/NCS?
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CN V trigeminal
CN VII facial CN XI spinal accessory |
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In a unilateral V nerve lesion, what blink reflexes are affected?
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In unilateral Vth nerve lesions, all three responses are equally affected.
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What responses are delayed or absent in a unilateral VII nerve lesion?
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In a unilateral VIIth nerve lesions, stimulation on the same side of the lesion will result in delayed or absent direct and indirect responses ipsilaterally but a normal indirect response contralaterally.
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What is the response when the V nerve is stimulated on the unaffected side?
|
When the nerve is stimulated on the unaffected side, both the direct and indirect responses are spared while the contralateral indirect response is affected.
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What are the three responses in a blink reflex study (mono or poly-synaptic, direct or indirect, and which CN nerve)?
|
-a direct and monosynaptic with the ipsilateral VIIth nerve nucleus.
- indirect and polysynaptic with the contralateral VIIth nerve nucleus. - polysynaptic to the ipsilateral VIIth nerve nucleus. |
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The blink reflex is the electrical equivalent of what reflex?
|
glabellar reflex
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|
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What medication may suppress a CRD?
|
corticosteriods
|
|
|
Name 4 myopathies causing CRDs?
|
Necrosis
Inflammation Muscle fiber splitting Acid maltase deficiency |
|
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CRDs are uncommon in what neuropathy?
|
acute mononeuropathy
|
|
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What muscle phenomenon may be produced by CRDs?
|
muscle hypertrophy
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