Agents - 4 - Electrical Currents for Muscle Contraction

neuromuscular electrical

NMES stands for _________________ stimulation

functional electrical

FES stands for _________________ stimulation

electrical muscle

EMS stands for _________________ stimulation

NMES

____ is for innervated muscle

FES

____ is for innervated or denervated muscle

EMS

____ is for denervated muscle only

NMES

the goal of ____ is strength and reeducation

FES

the goal of ____ is to facilitate or enhance functional movement

EMS

the goal of ____ is to preserve muscle while nerve regenerates, controversial

NMES

we spend most of our time in this course with which type of estim:

electrical currents, innervated

NMES is the use of ___________ to produce muscle contractions in _________ muscle

T

T/F: NMES is highly adaptable

F; 10% of people don’t tolerate estim

T/F: everyone can tolerate estim well

action potential propogation

___________________ is what causes the nerves to become depolarized and then muscle fibers innervated by them contract

smaller type 1, larger

_________ muscle fibers are activated before _______ muscle fibers

contractions (this is debated though)

NMES should be used with patient performing ___________ to maximize strength gains

disuse

NMES is very effective at strengthening fibers that are weak secondary to _______

physiologically initiated

(physiologically initiated/electrically stimulated) contraction : slow twitch type 1 first

electrically stimulated

(physiologically initiated/electrically stimulated) contraction : fast twitch type II first

physiologically initiated

(physiologically initiated/electrically stimulated) contraction : contraction force is low

electrically stimulated

(physiologically initiated/electrically stimulated) contraction : contraction force is high

physiologically initiated

(physiologically initiated/electrically stimulated) contraction : speed of contraction is slow

electrically stimulated

(physiologically initiated/electrically stimulated) contraction : speed of contraction is fast

physiologically initiated

(physiologically initiated/electrically stimulated) contraction : fatigue resistant

electrically stimulated

(physiologically initiated/electrically stimulated) contraction : fatigues quickly

physiologically initiated

(physiologically initiated/electrically stimulated) contraction : atrophy resistant

electrically stimulated

(physiologically initiated/electrically stimulated) contraction : atrophies quickly

physiologically initiated

(physiologically initiated/electrically stimulated) contraction : recruitment is asynchronous

electrically stimulated

(physiologically initiated/electrically stimulated) contraction : recruitment is synchronous

motor unit recruitment

there are often big gains at the beginning of a program because of increased _______________________

T

T/F: in initial weeks after a surgery or injury, the progress lost isn’t as much from atrophy as it is the muscles forgetting how to work together

muscle fiber size, motor unit recruitment

muscle strengthening can happen via increased _____________ or improved ______________

1

muscle re-education and activation is sometimes called phase ___

2

NMES for strengthening is sometimes called phase ___

T

T/F: you have to activate a muscle before you can strengthen it

II

NMES has more effect on type ____ fibers

physiological contractions

NMES can increase muscle strength and endurance when used with _________________

greater force (adjust pulse duration and amplitude)

NMES to increase strength needs contractions with _____________

prolonged stimulation of lower force

NMES to increase endurance needs contractions with ________________

50%

generally, ____ of max voluntary contraction is needed for strength

20-30%

generally, ____ of max voluntary contraction is needed for endurance

off time

with an increased _______, the patient can tolerate the stimulation treatment for longer

recovery

NMES can accelerate _______ where immobilization and rest lead to type II fiber atrophy

T

T/F: there is greater strength gains with NMES and exercise, than exercise alone

F: EQUALLY EFFECTIVE

T/F: NMES is more effective than voluntary contraction when performed at the same intensities

40-60

post op strength after TKA, is usually ___-___% of preoperative levels

I & II

with aging, there is a decrease in the NUMBER of type ( I / II / I&II ) fibers

II

with aging, there is a decrease in the SIZE of type ( I / II / I&II ) fibers

peripheral nerves

NMES can activate _______________ for muscle contraction

denervated

EMS is for __________ muscles

EARLIER

with NMES, a take home message is that using it ________ is better

UNSTABLE

NMES should not be used around _________ areas from surgery, fracture, or osteroporosis

precautions

_________ for NMES:

• impaired sensation

• impaired circulation

• impaired mentation

• skin disease/irritation

• neuropathies/denervation

• active epiphysis

• cardiac disease

symmetrical

with NMES, biphasic pulsed (symmetrical/asymmetrical) is more comfortable for larger muscles

asymmetrical

with NMES, biphasic pulsed (symmetrical/asymmetrical) is more comfortable for smaller muscles

asymmetrical

some studies found that biphasic pulsed (symmetrical/asymmetrical) current is more effective

burst modulated AC (BMAC), aussie

another name for russian is __________________ or _______

russian

_____________ is continuous wave of AC broken into bursts of many cycles grouped together

T

T/F: there is no pulse duration for russian

350-450 microseconds (usec)

the generic optimal starting parameters for pulse duration is ________

higher

(higher/lower) pulse duration is more effective

30-50 pps

the generic frequency parameters for NMES is _______

SMOOTH FORCEFUL

the goal with frequency is ______, ________ contractions

higher

(higher/lower) frequency causes more fatigue of muscles

50

a frequency >___pps can be used in later stages for hypertrophy

2500

the fixed carrier frequency for russian is _________ Hz

MAX TOLERATED

the NMES parameters for amplitude are ___________

strong tetanic contraction, >50%

the goal with amplitude for NMES is a _____________ at _______ of MVC

30%

generally, amplitude should start at ___% of MVC

70

hypertrophy happens at an amplitude of ___% of MVC

1-5 up, 1-2 down

generally, ramp time is ____ up and _____ down

less

a longer ramp means that there is (more/less) total activation time

2

the most common ramp is ___ seconds up

TOO LOW INTENSITY

one of PTs biggest flaws is ___________

1:5

a ____ duty cycle is the most common starting point

50

russian always has a ___% duty cycle

F; CAN STILL HAVE ON OFF TIMES

T/F: russian has a set duty cycle and does not have on off times

MAX FORCE

with duty cycle parameters for NMES, you want each contraction at ___________

10 minutes

_______ is the most common duration for NMES

10

with time and duration parameters, you want at least ____ contractions

medium

russian is considered a _____ frequency burst

10 ms burst, 10ms interburst interval

russian protocol duty cycle is _______ then __________

1:5, 10 sec:50 sec

a common on off time for russian is _________

target muscle size

electrode size should be matched to ___________

too much current density

if an electrode is too small, there is __________________

overflow

if an electrode is too large, there is __________________

bipolar

a ______ electrode configuration is the most common, with one pad over the motor point, and the other parallel with fiber direction

monopolar

having a dispersive pad only applies to ________

VISIBLE CONTRACTION

when monitoring treatment, the therapist should see a ___________