Electrodiagnostic Testinh Flashcards
(22 cards)
What are the 4 component of motor unit analysis
Amplitude
Rise time
Duration
Phases
increased amplitude is seen in what
Innervation
Decreased amplitude is seen in what
Myopathies
Amplitude reflects what
Fiber density
What is the Normal MAUP amplitude range
300-5000 uV (5 mV)
MAUPS that are reduced below normal values (300 uV or less) are often observed with what
Myopathies
Is myopathic short or long duration
Short duration
< 5 milliseconds
Is neuropathic short or long duration
Long duration
> 15 milliseconds
What is the normal MAUP duration range
5-15 milliseconds
How many phases does a normal MAUP typically have
2-3 phases
How many phases does a polyphasic potential typically have
5 or more phases
What is a polyphasic potential
Typically in tissue that has been denervated
What is recruitment
Orderly addition of motor units to increase force of contraction
What are the two ways contractions become stronger
Increasing firing rate
Increasing number of motor units
What is decreased recruitment
Few motor units fire at increased rate
What is early recruitment
Myopathic conditions
A large number of motor units recruited for a minimal contraction
T/f
Myopathic motor units cannot increase force output they quick,y recruit more motor units to increase contraction
True
What are the four characteristics of needle electromyography
Insertional activity
Examination of muscle at rest
Moto unit analysis
Recruitment
What is the normal insertional activity
150-300 milliseconds
When a needle is placed in a muscle and stops moving would should happen to the muscle
If healthy, should be electrically silent
What is decreased insertion activity
Atrophied muscle
<150 milliseconds
What is increased insertional activity
> 300 milliseconds
