Phys Neuro Testing

Question 1

Describe Mononeuropathy: Neuropraxia

Give example of diagnosis:

Answer 1

• Pressure, compression w/o Wallerian degeneration

- Carpal Tunnel

Question 2

Acute NCV studies Mononeuropathy: Neuropraxia =

Prolonged =

Answer 2

Acute = Increase latency/decrease CV distally
Chronic = Decrease amplitude of SNAP/CMAP

Question 3

EMG Acute Mononeuropathy: Neuropraxia =

Prolonged =

Answer 3

Acute = Usually normal
Chronic = signs of denervation

Question 4

Describe Mononeuropathy: Axonotmesis

Answer 4

-Demyelination/axonal damage

+Wallerian Degeneration

Question 5

NCV Mononeuropathy: Axonotmesis
Incomplete =
Complete =

Answer 5

Incomplete = Decrease amplitude SNAP/CMAP, increase distal segment latency
Complete = Absence of CMAP/SNAP

Question 6

EMG Mononeuropathy: Axonotmesis

Answer 6

• Prolonged insertional activity
• Fibrillation/+Sharp waves
• Polyphasic, initial reduced recruitment

Question 7

Describe Mononeuropathy: Neurotmesis

Answer 7

-Complete disruption

Question 8

NCV Mononeuropathy: Neurotmesis
Incomplete =
Complete =

Answer 8

Incomplete = Decrease amplitude SNAP/CMAP, increase distal segment latency
Complete = Absence of CMAP/SNAP

Question 9

EMG Mononeuropathy: Neurotmesis

Answer 9

• Prolonged insertional activity
• Abnormal activity at rest
• Fibrillations, sharp waves, fasciculations
• Polyphasic
• No voluntary activity

Question 10

Polyneuropathy -

Diagnoses -

Answer 10

• Diabetes neuropathy (axonal damage)
  1. Small nerve fibers
  2. Sensory fibers

Question 11

Polyneuropathy NCV

Answer 11

Decrease amplitude = decrease integrity

Question 12

Polyneuropathy EMG

Answer 12

1. Small nerve fibers 1st and EMG test big fibers
2. Sensory 1st so won’t change EMG
   Late stages:
   -Fibrillations, + sharp waves LE>UE
   -Increase amplitude and duration

Question 13

Demyelination - Hereditary

Diagnosis -

Answer 13

-Charcot-Marie-tooth = muscles weakness (muscle and sensory)

Question 14

Demyelination - Hereditary NCV

Answer 14

Increase latency and decrease CV

Question 15

Demyelination - Hereditary EMG

Chronic

Answer 15

Acute- not helpful
Chronic - +fibrillations, +sharp waves
-Increase amplitude and duration

Question 16

Demyelination - Acquired

Diagnosis

Answer 16

-Guillain-Barre = focal demylenation

Question 17

Demyelination - Acquired
NCV:
Before and after conduction block

Answer 17

• Before conduction block - increase latency and decrease CV, decrease amplitude
• After conduction block no changes

Question 18

Demyelination - Acquired

EMG

Answer 18

Not helpful acute stages

Question 19

NMJ Disorders

Diagnosis -

Answer 19

Myasthenia Gravis = decrease AcH receptors ->decrease contractility with use

Question 20

NMJ Disorders

NCV -

Answer 20

• Normal

- Use repetitive neuron stimulation = decrease amplitude over time

Question 21

NMJ Disorders
EMG
Acute/chronic

Answer 21

-Acute - can be normal because small contractions = no change
-Chronic - Decrease MUAP amplitude/duration
Polyphasic

Question 22

Myopathy

Diagnosis -

Answer 22

Muscular distrophy = decrease muscle mass

Question 23

Myopathy: Muscular distrophy

NCV

Answer 23

NCV - usually normal

Question 24

Myopathy: Muscular distrophy

EMG

Answer 24

Fibrillation, +sharp waves
Decrease amplitude
Decrease duration
Polyphasic