surface EMG biofeedback

Question 1

motor unit

Answer 1

body, axon, end plate

smallest unit of movement the CNS can control

Question 2

MUAP

Answer 2

motor unit action potential

excitatory stimulation to reach threshold of depolarization

Question 3

Is measured action potential the contraction

Answer 3

no its a phenomenon

Question 4

Ep testing

Answer 4

where neuro/mm abnormalities suspected. Not entry level

Question 5

techniques of Ep evaluation

Answer 5

SD curves
evoked potentials (motor / sensory nerve conduction test)
EMG

Question 6

motor nerve conduction test

Answer 6

indirect
estimates velocity of depolarization
measures mm action potential not the impulse

determines latency n velocity

Question 7

latency

Answer 7

duration between impulse and mm response

estimates rate of travel along alpha motor neuron
# of motor units in evokes mm action potential

Question 8

can latency calculate velocity

Answer 8

no

Question 9

velocity estimates what

Answer 9

conduction velocity along peripheral motor nerves

Question 10

how is velocity achieved

Answer 10

by measures two latencies (distal, and proximal)

Question 11

residual latency

Answer 11

proximal minus distal +

Question 12

difference sensory and motor evoked potentials

Answer 12

sensory smaller amplitude, single, negative phase. no delay (accurate latency)

motor are bi or trip phasic

Question 13

sensory / motor testing can only be carried out___ over peripheral nerve

Answer 13

distally

Question 14

to measure proximal conduction use ___

Answer 14

electronic reflex testing

Question 15

two ways to do electronic reflex testing

Answer 15

H reflex

F wave

Question 16

H reflex

Answer 16

electrically induced equivalent of tendon tap reflex

monosynpatic reflex arc
direct and latent

assess proximal nerve conduction

Question 17

Abnormal h wave

Answer 17

other than triceps its hard to elicit

Question 18

f wave

Answer 18

uses afferent / efferent components of same peripheral motor nerve

Question 19

what measures proximal conduction

Answer 19

H reflex and F wave

Question 20

difference in F and H

Answer 20

f wave is in most mm

H reflex in slow twitch mm

Question 21

abnormal F wave

Answer 21

slower conduction of motor axons

Question 22

centrally recorded evokes potentials

Answer 22

somatosensory evoked potentials
brainstems auditory evoked potential
visual evoked potentials

Question 23

somatosensory evoked potentials

Answer 23

stimulate distal peripheral motor nerve to minimal motor threshold

Diagnose CNS disorder in early stage showing latency in central pathways

Question 24

brainstem auditory evoked potentials

Answer 24

assess auditory pathways
used when demyelination, tumours are suspected
mostly be audiologists

Question 25

visual evoked potentials

Answer 25

detects compromise of optic nerve in early stage of disease (i.e MS) differentiates true and hysterical blindness

Question 26

EMG / voluntary potentials

Answer 26

compares electrical action of mm at rest vs voluntary

Question 27

Types of EMG electrodes

Answer 27

needle and surface

Question 28

__ amplitude seen before __ amplitudes in active contraction as force increases

Answer 28

smaller | larger

Question 29

is more than 500 usec rise time abnormal

Answer 29

yes

Question 30

is <60 per second normal in firing rate

Answer 30

yes

Question 31

is mm activity at rest normal

Answer 31

no

Question 32

whats discharge frequency

Answer 32

firing rate

Question 33

usual discharge frequency

Answer 33

5-15 per second

Question 34

whats normal discharge frequency

Answer 34

<60 per second

Question 35

electrical activity in mm is normal __ at rest

Answer 35

silent

Question 36

what happens to irritable mm vs fibrotic/ atrophied mm

Answer 36

increased insertional activity if irratable

Question 37

abnormal mm activity at rest suggests

Answer 37

neuropathy or myopathy

Question 38

what causes fibrillation potentials

Answer 38

motor nerve disruption

Question 39

types of abnormal mm activity

Answer 39

fibrillation potentials postiive sharp waves fasciculation potentials

Question 40

causes positive sharp waves

Answer 40

denervation or myopathy

Question 41

fasciculation potentials

Answer 41

spontaneous repetitive twitch like contraction looks same as MUAP

Question 42

causes fasciculation potentials

Answer 42

alpha motor neuron disease radiculopathies entrapment neuropathies

Question 43

when is fasciculation potentials considered significant

Answer 43

if associated w pos sharp waves and fibrillation

Question 44

Recruitment of motor units

Answer 44

lowest threshold first Type S FR FF

Question 45

type S motor units

Answer 45

slow contracting fatigue resistant (type1) small alpha motor neurone

Question 46

as force requirements increase, type S motor units ___ discharge frequency and __ motor units are recruits

Answer 46

increase more

Question 47

when stronger contractions are required the discharge frequency of type S and FR __

Answer 47

increase

Question 48

FR motor units

Answer 48

fast twitch fatigue resistant Type 2A slightly larger alpha motor neurone

Question 49

Type FF

Answer 49

fast twitch readily fatiguable 2b and largest alpha motoneurons

Question 50

the third class of motor neurone recruited

Answer 50

Type FF

Question 51

the most common PT clinical application of EMG is

Answer 51

surface EMG biofeedback (SEMG BFB)

Question 52

SEMG BFB

Answer 52

detects and ample mm motor unit potential surface electrodes gives feedback info to client to inc/dec mm training

Question 53

SEMG BFB uses

Answer 53

improves control over defective mm action / coordination | imporoves control over stress related conditions

Question 54

commonly treated conditions SEMG BFB

Answer 54

``` hemiplegia SCI partial spasticity dystonic conditions recovering peripheral nerve injuries retraining mm ```

Question 55

candidate selection SEMG BFB

Answer 55

``` condition cognition motivation visual / auditory perception potential for improvement ```

Question 56

Is Guillain barre, post CVA suitable condition for SEMG BFB

Answer 56

yes

Question 57

how do you know if condition is suitable for SEMG BFB

Answer 57

weak goes too much, too little too fast w motor control reduced intrinsic feedback (sensory loss) pain stress or urge incontinece

Question 58

can you do SEMG BFB is neglect or aphasia

Answer 58

you need to consider how severe they are

Question 59

do you know someones potential for SEMG BFB right away

Answer 59

not always apparent need to trial the intervention they need minimal voluntary control tho

Question 60

electrodes for SEMG BFB

Answer 60

larger for lower impedance and more signal along mm fibres on neutral site (bone or between two active sites)

Question 61

Leads on SEMG BFB

Answer 61

keep short and avoid movement to prefect artifact

Question 62

how to progression SEMG in uptraining

Answer 62

active to resisted to active lower sensitive move electrodes closer

Question 63

how to relax or down train SEMG BFB

Answer 63

``` position gravity assisted - resisted functional task increase sensitivity electrodes further adjust threshold ```

Question 64

evaluating SEMF BFB

Answer 64

changes in EMG output , frequency of target goal, length of time to activity is sustained , time required to reach threshold

Question 65

when to use SEMF BFB

Answer 65

inc vastus medialis activity in knee extension or controlled flexion reduce upper trap, scalene, TMJ, forehead activity