Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physical Agents > EMG Bio feedback/NCV > Flashcards

EMG Bio feedback/NCV Flashcards

1
Q

EMG biofeed back in general?

A

therapeutic use of instrumentation to detect feeback from MUAP by active muscle

signal is amplified and converted

used to increase or decrease muscle activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Does it measure actual events occuring?

A

Measures the highly correlated events such as periperal skin temp, finger photo transmission, electromyography

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What leads to change in ion concentration

A

increased perm to sodium and potassium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is ion concentration measured in?

A

microvoltage by the device

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Change in electrochemical gradient created by MUAP measured by?

A

electrodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which units are recruited first

A

smaller units recruited first then larger units with faster contractions may depress smalleru nits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

EMG amplification reflects

A 
number of active motor units
size of motor units
distance of active mm from electrode
size of recording area
interelectrode spacing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

EMG and Force relationship

A

Isometric is linear

concentric/eccentric is nonlinear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

3 kinds of electrodes?

A

2 active electrodes

1 ground electrode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How do we get to smoothened/integrated

A

2 active electrodes give off an amplified resultant signal that is subtracted from each other to get the amplified difference

Differential amplification removes extraneous noises
Common mode reflection ratio removes the common noise between the 2 electrode
Remaining noise is then filtered then amplified to get the raw activity (alternating) true electrical activity,

then rectified and integrated and smoothened

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Purpose of EMG

A

to change the MUAP to audiovisual to increase or decrease mm activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Advantages

A

immediate feedback/rewards that typically isn’t noted to allow for greater improvements

feedback without the constant supervision of the physical therapist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Indications

A

motor inhibition
motor recruitment
total body relaxation (generalized pain/stress) goal to decrease undesired muscle tension= muscle/stress relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Contraindications

A

when mm contraction would make the condition worse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Safe and Effective application

A

consent
select appropriate muscle group with goal
alcohol the skin
place electrodes parallel to muscle fiber belly
place ground electrode on bony prominence
set gain/sensitivty threshold, goal on EMG unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What can nerve conduction/EMG diagnose

A

peripheral nn lesion, mm injury, ongoing process of the neuromuscular system

establish correct diagnosis
localize lesion
determine treatment
info on prognosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Hardware

A

EMG machine, monitor, amplifier, stimulator, needle electrode, recording electrode

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Surface vs. Needle

A

Surface: disposable/nondisposable, ring or disc, all surface electrode

Needle: disposable, mono/bipolar concentric, active is needle, all other are surface

19
Q

General consideration

A

replacing electrode
alcohol/clean skin
disposing of needles in sharps container
measuring site with tape

20
Q

Precautions

A

morbidly obesed
thin individual
bleeding disorder
blood cautions

21
Q

Contraindications

A 
automatic cardiac defibrillator
pacemaker
metal lining
soft tissue infection
indwelling catheter
22
Q

Variables

A

25 for room temp, 31 for UE, 29 for LE

Coldertemp: requires more current to get to AP, longer to go from rest to AP, sodium channels open slower=decreased NCV, remain open longer for increased AMP/Duration

23
Q

Age and myelination

A

complete by age 5
mild decrease by 40
sig decrease by 70

24
Q

UE vs LE nerves

A

UE: shorter latency, increased NCV, increased temperature, shorter nerves, thicker diameter

25
Q

Wave form analysis

A

measures largest, fastest fibers

Evoked potentials from sensory nerve fibers. SNAP, orthodromic or antidromic

Evoked potentials from muscle. Compound motor action potentials. orthodromic

shape, area, rise time, duration, amp affected by axonal pathology, latency affected by demyelination, NCV affected by pathology

26
Q

Insertional activity

A

brief electrical activity with insertion
crisp
healthy muscles don’t make a sound if needle stops moving
damages the muscle when inserted, test all 4 quadrants

normal muscles are crisp, 150ms
decreased insertional activity atrophied muscles, needle into the sand
increased insertional activity, muscle pathology, sharp positive waves that don’t last, >300ms

27
Q

Examination of muscle at rest

A

abnormal spontaneous muscle activity

denervation, positive membrane caused by inc sodium

28
Q

Positive sharp waves

A

dull thud, mm ap, recorded from mm with innervation impairment, positive deflections from basline 0.5 to 15Hz

29
Q

Fibrillations

A

single muscle fibers firing autonomously
rain drops hitting roof of car
impair innervation
regular pattern

30
Q

Complex Repetitive discharge

A

spontaneous activity
stim adjacent mm
motor boat misfiring
>6months neurogenic/myopathic condition

31
Q

Myotomic discharge

A

prolonged fashioned AP
delayed relaxation
dive bombing waxing/waning

chronic radiculopathies/neuropathies
myotomic dystrophy
polymyelitis

32
Q

Myokymic discharge

A

group of spontaneous motor potentials
continuous or discontinous
regular firing pattern/rhythm

33
Q

Spontaneous end plate potential

A

if needle in the endplate of health muscle, painful and spontaneous activity, must reposition

34
Q

Miniature endplate potential

A

short duration/amp, monophasic, spontaneous release of AcH

35
Q

Endplate spike

A

short duration, int amp, depolarization from a single fiber

36
Q

Motor unit amplitude

A

increases when reinnervated
represents fiber density
peak to peak
decreases when myopathic condition

37
Q

Motor unit duration

A

increase with neuropathic
decreases with myopathic
initially from baseline
normal is 5-15ms

38
Q

Motor unit phasic

A 
phase is when it crosses baseline
from negative to positive pole
polyphasic >4
normal is <4
10-35% of normal muscle is polyphasic
39
Q

Recruitment how to inc force

A

increase firing rate

increase units recruited

40
Q

How to measure units/second

A

measure motor units repeated across the sweep
multiply by 10

yields the MUAP/1second

41
Q

decreased recruitment

A

nerve trauma, neurogenic

increased firing rate and decreased recruitment

42
Q

Early recruitment

A

myopathic, recruits large units early with minimal force produced

43
Q

Pitfalls

A 
bad subj/obj exam
technical difficulties
measuring error
temperature
anamolous innervation
accessory peroneal nerve

Physical Agents (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions