Electrical Therapy Overview (Lecture 0 - from last test)

Question 1

Polarity is

Answer 1

the net charge of the object

Question 2

The amount of attraction or repulsion by an electric field is

Answer 2

Voltage
* The amount of energy required to move current
* This high voltage is what puts electricty down power lines

Question 3

Units for voltage

Answer 3

Joules/Coulombs (Force*m /Net charge)

m = distance

Question 4

Neural communication occurs due to changes in change (think depolarization / repolarization)

Question 5

Materalis in which ions and electrons can move freely are called
* give some examples of these (2 outside human 2 inside)

Answer 5

Conductors

Metals / water

Muscle, nerve, bodily fluid

Question 6

Materalis in which charged particals do not move freely

Give some examples of these (2 inside human 2 outside)

Answer 6

Insulators

Rubber / plastic

Fat tissue / bone

Question 7

Theres a powerline down in a puddle of water. Why would it not be safe to step in it?

Answer 7

Because water is a conductor and could put that electricity into you

This is why there is plastic around wires (acts as an insulator)

Question 8

The movement of ions/electrons in response to voltage force

Answer 8

Current

Question 9

What is current directly proportional to?

Answer 9

Voltage

current = the movement of ions/electrions in response to voltage force
* so these ions move in response to the amount of voltage pushing them
* if you have more voltage you’re going to have a faster current

voltage = the amount of energy required to move current

These wheels are churning in such a way to facilititae water moving. The amount of energy required to move those wheels at that speed is the voltage

Question 10

what is current measured in?

Answer 10

A or mA

Question 11

What is OHM’s Law

Answer 11

Current (AMP) = Voltage / Resistance (ohm)

Resistance in the body
* Skin
* Hair
* fascia
* Ligament
* Callus
* Fat
* Bone
* Tendon
* Scar

Question 12

Which image has more voltage?

Answer 12

A

because the voltage being high makes the current go faster

Question 13

Would something with more water in it have more or less resistance?

Answer 13

More water = decreased resistance

Question 14

If we have high resistance how do we keep the same amount of current?

Answer 14

Increase the voltage

Current (AMP) = Voltage / Resistance (ohm)

So if someone has hairy legs (resistance) we would increase the voltage to keep the same current of electricity going into them

Question 15

KNOW: Someone w/ excess adipose tissue would need more estem because fat is an insulator

Question 16

Of adipose fat, ligament, skin and bone which one would have the most resistaance and why?

Answer 16

Bone because it has the least water (which is a conductor)

Question 17

Which kind of current is continuous and unidirectional?

Answer 17

Direct current

Always flowing in one direction

Question 18

A direct current can flip to being negative or even have gaps in it. However it must always flow on direction for how many seconds before flipping or stoping

Answer 18

1 second

Question 19

KNOW: with a direct current you’re going to need a cathode and an anode. Which one is positive and which one is negative?

Answer 19

Cathode = negative charged current going in it.
* Think its a negative experience to have a cathiter
Anode = positive charged current going in it
* analgesic is positive

In the picture below we have a negative cathode which is driving the negative current out of the area and going to the anode (which is positive so it attracts that displaced negative current)
* Utilized w/ iontophoresis (anti inflammatory by being negatively charged which drives the other negatives away from the area making it more positive) - think using this for tendon pathologies (inflammation itis)

Question 20

What kind of current is uniterrupted bidirectional flow of ions/electrons?

Answer 20

Alternating current

Rather than it being consistent then switching (direct current) its switching the entire time

Question 21

How often does an alternating current switch directions?

Answer 21

At least 1 time per second

Question 22

What are the two kinds of Alternating current?

Answer 22

Burst modulated Alternating current (normally skeletal muscle stimulation)

Amplitude modulated Alternating current

Question 23

What two kinds of currents are burst modulated alternating currents?

Answer 23

Russian / Aussie currents

Question 24

What is the one kind of amplitude-modulated alternating current?

Answer 24

Interferential current

Question 25

KNOW: Pulsed current is a modulated direct current or modulated alternating current

Question 26

are these pulsed currents alternating or direct?

Answer 26

Direct because they go the same direction for more than one second (in this picture they never change directions, just take breaks) NOTE: We change the amplitude / duration of the currents to make them look like triangles / rectangles /squares

Question 27

Which one delvers the most current into the body?

Answer 27

Rectangle Duration is longest and amplitude is the same

Question 28

What is a pulse?

Answer 28

One electrical event would be the top ones the picture below

Question 29

What is a burst?

Answer 29

One or more pulses combined and separate from another group of pulses * used most often in skeletal muscle stimulation

Question 29

What is a carrier frequency?

Answer 29

Frequency of the little waves inside the burst a lot of times this is preset

Question 30

What is burst frequency?

Answer 30

**How many bursts per second**

Question 31

Would increasing burst frequency increase the total energy delivered?

Answer 31

Yes - more bursts = more energy delivered

Question 32

What is a monophasic pulsed current?

Answer 32

All the pulses are in the same direction (positive or negative)

Question 33

What is a biphasic pulsed current?

Answer 33

All the little pulses are in positive AND negative directions

Question 34

Is this monophasic or biphasic?

Answer 34

Monophasic (dont switch direction)

Question 35

# **** Is this monophasic or biphasic?

Answer 35

Biphasic - switch directions

Question 36

A pulse is defined as one electrical event - notice it can go negative and positive and still be one electrical event as long as theres no break between

Question 37

Notice the difference between phases and pulses * pulse = 1 electrical event * phase = the amount of time it stays negative or positive w/o a break

Question 38

What is amplitude?

Answer 38

Intensity How high those phases are

Question 39

pulse duration = time the pulse takes

Question 40

What is a duty cycle?

Answer 40

Percentage of the on time (On time/total time)*100

Question 41

What carries a net charge - symmetrical pulses or asymettical pulses?

Answer 41

asymmetrical

Question 42

Documentation: * waveform type and shape (symmetrical / asymetrica / mono-/biphasic / square, tectangle, triangle, ramp up / ramp down * Pulse frequency * Pulse duration

Question 43

If you decrease pulse duration you're going to need to increase amplitude (intensity) to see an effect You don't want to have to short of a pulse duration because you're going to need a really high amplitude which could stimulate a nociceptive nerve

Question 44

Bodies physiological response to electric current: Thermial: * Any type of energy that were shooting anywhere can turn into heat * Friction is generated by moving particles and is transferred into heat energy * **HOWEVER - the tissues that generate this thermal energy (friction) are also going to be the same tissues that provide resistance (don't have water in them). So things like superficial hair, dry skin, lotions, or oils will all create more of this friction force which will generate more thermal energy (heat)** - this should not be a heat generating experience for the pt (this is an abnormal response - stop treatment and inspect the skin) Chemical: * Sodium / Cloride in extra cellular fluid are affected * **Ion gradient (sodium / k+ pump) to facilitate localized change in PH** Physical: * Based on stimulation / depolrization of cells * Permeability of the cell membrane to** Na+ is increased** - reducing the membrane potential * Ions then move across membrane causing deporalization * **Skeletal muscle stimulation works via motor nerve deporalization not muscle cell stimulation** * **So this works by activating the motor nerve - does not directly activate the skeletal muscle**

Question 45

KNOW: For estem to work we need sufficent amplitude and duration

Question 46

Are large or small nerves depolarized first?

Answer 46

Large

Question 47

Which nerve are considered large diameter nerves? Which nerves are stimulated next next

Answer 47

Alpha a nerves: Proprioception / motor nerves Beta nerves: Touch / pressure Delta nerves: Pain / temperature: * So if they're experiencing a change in temperature then were giving way to much stimulation because these nerves are fairly small and should not be turned on

Question 48

With estim we can get the deporalization of the muscle to have a sustained effect (turn on and stay on) what is this called?

Answer 48

Tetany

Question 49

If amplitude is to high (they're having pain) we can lower amplitude and increase pulse duration + move pads (not over those resistors [body hair / bones / tendons / how dry skin is] we typically want to be over muscle mass) + increase ramp up / ramp down time (further decreasing that amplitude)

Question 50

What kind of current is this?

Answer 50

Alternating

Question 51

What kind of current is this?

Answer 51

Burst modulated alternating current

Question 52

What is burst frequency for russian? (how many times per second a burst happens) What is carrier frequency for russian (how many small waves happening in each burst)

Answer 52

50Hz 2,500 Hz essentially the top one in the picture below is scrunched up into each burst (will alternate 2,500 times to = 1 burst)

Question 53

How long is the burst duration for russian (how long each burst lasts)

Answer 53

10 msec

Question 54

What is the duty cycle for russian?

Answer 54

50% (the on and off times are =)

Question 55

What was the original protocol for russian current

Answer 55

10 seconds on 50 seconds of rest 10 rounds

Question 56

KNOW: Russian is utilized for activating skeletal m

Question 57

They shortened the burst duration but increased the burst frequency Evidence suggests: * greater torque production * effiency * decreased rate of muscle fatigue * (compared to russian) beucase this is a shorter one there will be decreased m fatigue (because the time under tension is a little bit less)

Question 58

Question 59

High volt pulsed current primarily used for tissue repair / wound healing Current of high amplitude that are twin peaked and monophasic (always in the same direction) * Now were dealing w/ a polarity (driving negative or positive) very high peak voltage Much shorter pulse duration Very low duty cycle this doesnt cause tissue damage because were delivering it so quickly * think about just touching a hot stove for a milisecond - you wont burn yourself One electrode placed on treatment area, other is away from treatment site * this will produce a polarity (driving current) KNOW: that because it has a high voltage our duty cycle, pulse duration, and duty cycle are very small (because out intensity is so high) **used for tissue repair and wound healing**

Question 60

Interferential current (IFC) - most common types for **PAIN MODULATION** You're going to deliver two currents. * there will be 2 electrodes each with their individual currents * The 2 currents will be directed to intersect (criss cross) * The pulse shape will vary depending on the currents of each pad * most of the time your frequency will be much higher in kilohurts instead of hurts * You always put them in a criss cross fashion because the two currents are placed so they intersect **with your treatment in the center** * Peripdocially they waves will since and produce a megawave because the combine or have summation (waveforms add together) * they can also cancel each other out when one wave is coming in positive and the other one is in the nagtive zone at the time With this one were modulating the amplitude * We essentailly will change the amplitude to change the intensity instead of creating bursts of waves and gaps between (there are waves the entire time - its just the size of those waves that we care about) NOTE: The "beats" are the high points of those waves (where 2 sum together perfectly to create a high point) Beat frequency = how often the waves sum togther and createa a maximal peak For muscle tetany beat frequncy = 50hz * so for muscle contraction you would want to go below that for pain modulation beat frequency = 100hz * used for this most

Question 61

What is beat frequency?

Answer 61

how often the waves sum togther and createa a maximal peak

Question 62

Things we can change within IFC Sweep: * **this modulates the beat frequency (how often we hit those high peaks)** * So we can have a high or low beat frequency during the treatment * How often those waves come togteher Vector scan: * Increases the size of treatment area * Remember treatment area is normally in the center (where they criss cross) * With this it can increase the treatment area * **If you want to be very focused w/ your treatment = leave vector scan off * With vector scan on we increase the size of our treatment area** KNOW: electrodes should be applied in a crisscross pattern w/ treatment area in the center Premodulated IFC: intereference happens before they go out - so you don't need to put the electrodes out in a crisscross manner (premodulated happens within the unit) * A version of IFC where intereference occurs inside unit prior to being applied to pt via electrodes *

Question 63

Microcurrent (Low intensity DC) intensity = Below 1 miliamp * Because this is so low we can use direct current * Insufficent to depolarize sensiry or mtoor nerve = this makes it good for tissue healing * staying below the radar Pulse duration = 0.5 seconds = makes sense because amplitude is so low Typically a higher frequency because amplitude is so low Cathode (negative) = on the treatment side * Drive negative out and create a more positive unflux of potassium to create a more permiable cell membrane (make it depolrize again?) Anode (positive) Skin injury: we want positive ions from deeper tissues to go to the skin to promote healing * Drive out positive charge so that new positive comes in We put cathode over wound side (negative) to drive out the other negative * dermal wounds (cathode over wound site) * Increase fibroblast and granulation activity (because we drove out the other positive that was there this rushes in) Only used in out patient clinic for wound care

Question 64

Symmetrical Biphasic pulsed current reversed Direct current then interupted and repeat more tolerable than russian can be burst modulated