Hereditary
Name the drug helpful in the treatment of ALS
Riluzole
Name the common abrnomal EDx finding in GBS
Abnormal F waves
What explains post exercise facilitation in Lambert Eaton?
Calcium influx
How do we define innervation ratio and name a muscle with a large innervation ratio?
Amount of muscle fibers belonging to a single axon
Name the pure sensory nerve off the femoral nerve
saphenous nerve
A 7-year-old boy present with bilateral hand intrinsic muscle atrophy, toe-walking, and pes cavus. Name the disease.
CMT1. The demyelinating form (CMT I) typically has onset in early childhood. Marked slowing of motor conduction velocities, usually to less than 50% of normal, is often present in early childhood. Needle EMG abnormalities include defibrillation with positive sharp waves, decreased interference pattern, and large amplitude polyphasic MUAPs.
What does a steroid myopathy look like on EMG and why?
Normal. A steroid myopathy effects type II fibers
Increment on repetitive nerve stim is a hallmark of disease commonly seen in what type of cancer?
Lambert Eaton Syndrome, lung cancer
What happens to amplitude and latency when we warm the limb?
latency is shortened
amplitude is decreased
What is the origin of the nerve that innervates the lateral forearm?
LAC off the musculocutaneous nerve
Which of the following characteristics helps to identify inherited demyelinating neuropathy?
A. Conduction block and temporal dispersion
B. Pure sensory involvement
C. Uniform symmetric slowing of conduction
C. Uniform symmetric slowing of conduction
What nerve is likely effected in lateral scapular winging
Spinal accessory muscle (traps)
A variation in the interpotential interval between paired action potentials of the same motor unit is defined as:
Jitter
Why are SNAPs normal in radiculopathy
The disease impacts proximally to the DRG while EMG assesses distally
Name the muscle innervated by the common peroneal nerve
short head of biceps femoris
Which of the following electrodiagnostic studies is most useful in the evaluation of a Stiff Person Syndrome?
A. Repetitive Nerve Stim
B. Dual Channel EMG of antagonist muscles
C. Single fiber EMG of affected muscles
B. Dual Channel EMG of antagonist muscles
At lesion in what anatomic locations results in dysfunction of the infraspinatus but not the supraspinatus
The spinoglenoid notch
Post exercise decrement is commonly seen in a particular NMJ disorder. If this disorder was diagnosed what type of CT scan becomes indicated?
MG. CT chest looking for a thymoma. Removal can be curative.
Post-activation exhaustion refers to the smooth decrement of at least 10% that occurs 2-4 minutes after exercise as a feature of Myasthenia Gravis (MG).
What are satellite potentials?
Small potentials seen in early reinnervation. They are time-locked and often trail the main MUAP.
What radial muscles are spared in a spiral groove fracture?
triceps and anconeus
A connection of the recurrent branch of the median nerve in the hand to the deep motor branch of the ulnar nerve producing an all ulnar innervated hand is known as a what?
Riche-Canniue anastomosis
Nerve entrapment syndrome that can be mistaken for tennis elbow
Radial tunnel syndrome. Entrapment between brachialis and BR in the radial tunnel
Single fiber EMG testing is most helpful in order to:
Rule OUT NMJ disease:
Single fiber EMG (SFEMG) has a very high sensitivity of approximately 99%, but low specificity in the evaluation of a neuromuscular junction disorder.
What happens when we raise the low frequency filter?
decrease in amplitude, decrease in in peak amplitude, does not change onset latency
What muscles are innervated by the AIN
pronator quadratus, flexor pollicus longus, flexor digitorum profundus 2,3