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Electrical Stimulation I
Iontophoresis, Interferential Current, TENS
211
Medical
Graduate
07/15/2015

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Term
Biophysical Effects of E-Stim: 1: modulate...
Definition
pain
Term
Biophysical Effects of E-Stim: 2: in regards to swelling
Definition
reduces swelling
Term
Biophysical Effects of E-Stim: 3: in regards to tissue
Definition
heats it
Term
Biophysical Effects of E-Stim: 4: reeducates what?
Definition
muscles
Term
Biophysical Effects of E-Stim: effect on joint restrictions
Definition
decreases
Term
Biophysical Effects of E-Stim: 6: effect on blood flow
Definition
increases it
Term
unit of current is what?
Definition
amperes
Term
current is what exactly?
Definition
the rate at which electrons flow
Term
force that moves electrons
Definition
voltage
Term
a term used to describe electrical charge
Definition
coulomb
Term
one coulomb equals what?
Definition
6.25 x10^18 electrons per second
Term
What are the 3 types of current
Definition
continuous direct, pulsed direct, alternating
Term
current which flows in only one direction for at least 1 second. aka monophasic, galvanic, unidirectional
Definition
direct current
Term
current that flows in only one direction for less than 1 second
Definition
pulsatile
Term
3 ways to modulate DC
Definition
reversing polarity, interrupting current flow, ramping the DC
Term
reversing polarity to modulate DC minimizes this risk
Definition
burn as a result of electrochemical build up
Term
how is DC polarity reversed (3)
Definition
manually reversing the +/- electrodes, flipping the polarity switch on the device, or by a preset internally in the device
Term
in order to DC to be modulated via interrupting current flow, how long must the interruption time be
Definition
greater than 1 second
Term
interrupting DC flow is commonly used to do what?
Definition
stimulate denervated muscle to cause a muscle twitch
Term
ramping DC refers to what
Definition
reaching peak amplitude from 0, or reaching 0 from peak amplitude
Term
alternating current flows in which direction
Definition
+ and - directions
Term
alternating current is also called what?
Definition
biphasic or bidirectional
Term
what is important to note about AC aside from it being bidirectional
Definition
the + and - components can be either symmetric or asymmetric
Term
what are the 3 ways to modulate AC current
Definition
modulate phase parameters, current modulation, ramping/surging
Term
modulating phase parameters of AC includes what
Definition
duration, intensity, rate
Term
AC current modulation is good for what
Definition
muscle reeducation
Term
AC current modulation involves changes in what
Definition
intensity through interruptions in the current short enough to not be percieved, or long enough to be perceived
Term
what is the purpose of ramping/surging AC current
Definition
patient comfort
Term
uni or bidirectional flow of charged particles which periodically ceases for a finite period of time
Definition
pulsatile current
Term
monophasic pulsatile current consists of what
Definition
one phase/one pulse either + or -
Term
describe biphasic pulsatile current
Definition
one half of the cycle is above the baseline and half is below
Term
types of biphasic pulsatile current
Definition
symmetric, asymmetric
Term
describe polyphasic pulsatile current
Definition
3 or more phases are produced in a single pulse
Term
a change in the waveform by changing any one of the waveforms's variables (amplitude, frequency, duration)
Definition
modulation
Term
waveform's variables
Definition
amplitude, frequency, duration
Term
modulation delays what
Definition
accommodation or becoming accustomed to the stimulation
Term
name of the + electrode
Definition
anode
Term
name of the - electrode
Definition
cathode
Term
what reaction occurs under the anode (+ electrode)
Definition
acid reaction
Term
what reaction occurs under the cathode (-electrode)
Definition
alkaline reaction
Term
repolarization of the muscle results in what more specifically
Definition
hyperpolarization
Term
which electrode is considered the active electrode
Definition
cathode
Term
why is the cathode considered the active electrode
Definition
underneath the electrode is the lowest threshold for depolarization and the Estim is typically perceived first under the cathode
Term
resting membrane potential
Definition
-90 mV
Term
resting membrane potential for peripheral nerve fibers
Definition
-60 mV
Term
Why is there a lot of impedance to current at the skin?
Definition
d/t a relatively low concentration of fluid
Term
What should NOT be done to try and decrease impedance of the skin
Definition
increasing the amplitude of the current
Term
Why should you not increase the amplitude in order to decrease the impedance of skin
Definition
build of heat under teh electrode causing and electrical burn
Term
skin impedance can be decreased by (3)
Definition
using a heaitng modality to warm the skin, hydrate the skin, cleaning the skin with alcohol
Term
3 types of electrodes
Definition
carbon electrode, thin metal pads, adhesive
Term
type of electrode made up of flexible, rubber pads with a moist sponge or gel interface
Definition
carbon electrodes
Term
electordes that are not pliable with a sponge interface
Definition
thin metal pads
Term
type of electrode with a conductive gel interface
Definition
adhesive
Term
how would you increase current density to a trigger point
Definition
place a smaller electrode on the trigger point
Term
increased current density creates what?
Definition
a greater effect on the tissue and the patient's perception of the stimulus is greater
Term
what is the minimum distance between electrode pads
Definition
the diameter of 1 pad
Term
what should the orientation of the electrodes be?
Definition
longitudinal or perpendicular to the mm fibers
Term
a monopolar electrode set up is used for what current
Definition
AC and DC
Term
size of the electrodes used for monopolar set up
Definition
electrodes of different sizes
Term
how many channels are used in either monopolar set up
Definition
1 channel
Term
types of leads used in monopolar set up
Definition
2 leads, bifurcated leads
Term
how many active electrodes are there in the monopolar set up with 2 leads
Definition
1
Term
how many active electrodes are there with bifurcated monopolar set up
Definition
2
Term
difference between teh active electrodes in the monopolar set ups
Definition
nothing, their surface area must be less than the dispersive pad
Term
electrode size and current densities of the bipolar set up
Definition
same size electrodes, equal current density
Term
types of leads used for bipolar set ups
Definition
bifurcated
Term
in a bipolar set up, the leads are bifurcated leading to how many treatment electrodes
Definition
4
Term
in the bipolar set up, crossing the 2 bipolar leads produces what
Definition
interference
Term
term used to describe that the electrode must conform to the body part to maximize conduction
Definition
electrical coupling
Term
what could be used to improve electrical coupling (6)
Definition
flexible pads, inflexible pads, straps, conductive liquid, moist sponge, or gel
Term
to generate a tetanic contraction what must the frequency be
Definition
>33Hz
Term
increasing the frequency of stimuli progressively fuses the individual muscle twitches to a point where individual muscle twitches are not discernable
Definition
tetanic contraction
Term
purpose of Estim for innervated muscle
Definition
strengthen weakened muscle
Term
purpose of estim for denervated muscle
Definition
minimize the atrophy that takes place to the affected muscles
Term
muscle atrophy is not the real problem in itself, what is? (2)
Definition
muscle fiber degeneration and fibrosis
Term
denervated muscles differ from normal muscles in these 3 ways
Definition
fibrillation, AcH hypersensitivity, less negative resting membrane potential
Term
spontaneous uncoordinated contraction of individual muscle fibers not visible to the naked eye
Definition
fibrillation
Term
in denervated mm, the resting membrane potential is what
Definition
-60 mV
Term
the resting membrane potential of denervated muscle is -60 mV, making it easier for what?
Definition
for the muscle to fire
Term
4 arguments for the use of estim for denervated muscle
Definition
slow muscle atrophy, minimize loss of muscle mass and strength, muscle fiber size can be maintained, limit edema and venous stasis delaying muscle fiber fibrosis and degeneration
Term
3 arguments against the use of ES for denervated muscle
Definition
may interfere with regeneration thus delaying functional return, disrupt the regenerating neuromuscular junction slowing re-innervation, may traumatize denervated muscle since it is more sensitive to trauma than normal tissue
Term
Why can't you substitue normal muscle innervation with ES
Definition
quality and quantity of the contraction does not approach that of normal mm. There is a constant leakage of Ach that keeps muscle alive. Denervated mm loses this leakage of Ach and degenerates even with Estim
Term
the intensity of the current needed to produce a minimal muscle contraction
Definition
rheobase
Term
the duration of the stimulus at twice the rheobase intensity
Definition
chronaxie
Term
what is the chronoaxie of denervated muscle
Definition
> 1ms
Term
what type of rise time should be used with denervated muscle? why?
Definition
fast or slow, denervated muscle does not accomodate
Term
9 general indications of estim
Definition
pain modulation, muscle spasm, impaired ROM, muscle reeducation, disuse atrophy, soft tissue repair, edema reduction, reduction of spasticity, denervated muscle
Term
how does estim provide pain modulation
Definition
gate theory of pain, initiation of descending inhibition mechanisms (opiate production)
Term
how does estim treat muscle spasm
Definition
via muscle fatigue caused by sustained tetanic contractions, muscle pump: modulation in current causes contraction and relaxation of the muscle to improve circulation
Term
how does estim treat impaired ROM
Definition
decreasing pain, decreasing edema, mechanical stretching of connective tissue and muscle
Term
how does estim reeducate muscle
Definition
act as an active assistive exercise, provides proprioceptive feedback, assists in coordinated muscle movement
Term
how does estim prevent disuse atrophy
Definition
muscular pumping minimizes/reverses atrophy
Term
which currents help in soft tissue repair
Definition
pulsed (mono, bi, and polyphasic)
Term
pulsed currents with what type of modulation aid in soft tissue repair
Definition
interrupted modulation
Term
which current type has bactericidal effects
Definition
monophasic currents
Term
how does estim help with edema reduction
Definition
muscle pump increases lymph and venous flow, interstitial proteins found in edema can be repelled from area with application of (-) charge
Term
how does estim reduce spasticity
Definition
fatigue of the agnoist, reciprocal inhibition (stimulates the antagonist to inhibit the agnoist)
Term
6 general contraindication of estim
Definition
healing fractures, active bleeding, malignant tumors, phlebitis, superficial metal implants, pharyngeal or laryngeal muscles
Term
1 general precaution of estim
Definition
demand type pacemakers or other myocardial disease
Term
1 absolute contraindicaiton to using estim
Definition
any evidence of faulty or frayed wires or ifi the unit is not connected to GFI (ground fault interruptor)
Term
TENS stands for...
Definition
Transcutaneous Electrical Nerve Stimulation
Term
what is TENS primarily designed for
Definition
provide afferent stimulation for pain management through the skin
Term
pain modulation through activation of central inhibition of pain transmitters
Definition
gate control theory
Term
Gate Control Theory: Large diameter A-beta fibers activate inhibitory interneurons founds where
Definition
dorsal horn of the spinal cord
Term
Gate Control Theory: large diameter A-beta fibers activate inhibitory interneurons found in the dorsal horn of the spinal cord found in the dorsal horn of the spinal cord producing what?
Definition
inhibition of (closing the gate to) smaller A-delta and C-fibers (which normally transmit pain)
Term
Gate Control Theory: what happens if accomodation occurs
Definition
gates open back up and pain returns
Term
pain modulation through descending pathways generates what?
Definition
endogenous opiates
Term
stimulation of the descending pathways causes a release of what throughout the CNS
Definition
enkephalin
Term
stimulation of the descending pathways causes a relase of what from the pituatary gland
Definition
beta-endorphin
Term
TENS opiate release: reduction of pain perception is caused by applying the electrical current to what areas
Definition
areas clsoe to the site of pain or to trigger points
Term
waveform of TENS, 2 features
Definition
biphasic (symmetrical or asymmetrical), balanaced
Term
key features of a balanced waveform (2)
Definition
equal number of electrical charges in each phase, surface area under each phase is equal
Term
Why is it important to use a balanced waveform with TENS? (2)
Definition
avoid irritiation, TENS pain control is used for long durations, multiple times a days
Term
what is the pulse duration/width of TENS
Definition
50-400 microseconds
Term
what is the pulse frequency range of TENS
Definition
1-200 Hz
Term
what is the amplitude/intensity of TENS
Definition
.1 mA-120 mA
Term
depending on the TENS settings, what types of nerves can it effect (3)
Definition
sensory, motor, sensory-motor-nociceptive
Term
What are the 5 modes that a TENS can be programmed to deliver
Definition
conventional, acupuncture-like (strong low rate), burst, brief intense, modulation
Term
parameters of conventional mode TENS (duration, frequency, intensity)
Definition
short duration, high frequency, comfortable intensity
Term
why is the conventional mode the most frequnely selected by thereapist
Definition
generally the msot comfortable application
Term
how does the convential mode modulate pain
Definition
through sensory nerve fibers, gate thoery
Term
how quickly does analgesia take place in convential mode
Definition
a few minutes
Term
how long does analgesia last through convential mode
Definition
from turning off the machine to a few hour after the machine has turned off
Term
pulse duration, and pulse frequency of convential mode
Definition
<150 microseconds, >80 Hz
Term
acupuncutre-like mode parameters (frequency, intensity, duration)
Definition
long duration, low frequency, comfortable current intensity
Term
acupuncture mode depolarized what nerves
Definition
sensory and motor nerve fibers
Term
acupuncutre-like mode modulates pain via what
Definition
opiate production
Term
when does analgesia take place when using acupuncture-like mode
Definition
hours, slow to take place
Term
how long does anaglesia last from acupuncture like mode
Definition
longer than conventional TENS, hours
Term
pulse duration and pulse frequency of acupuncutre like mode
Definition
<150 microseconds, <10 Hz
Term
burst mode paramters (duration, intensity, frequencY)
Definition
bursts of pulses, low frequency, comfortable intensity
Term
this mode of TENS may produce visible twitching (fasciculation) of muscle
Definition
burst mode
Term
burst mode depolarizes which nerves
Definition
sensory and motor nerves
Term
hwo does burst mode modulate pain
Definition
via opiate release
Term
how long does analagesia take to set in using burst mode
Definition
within hours
Term
how long does analgesia last usign burst mode
Definition
many hours after use
Term
pulse duration and pulse frequency of burst mode
Definition
200-500 microseconds, 1-5 Hz
Term
brief intense mode parameters (duration, intensity, frequency)
Definition
long duration, high frequency, tolerable current intensity
Term
how long is the duration of brief intense mode usually
Definition
no greater than 15 minutes
Term
brief intense mode depolarizes what nerves?
Definition
sensory, motor, nociceptive
Term
brief-intense mode modulates pain how
Definition
opiate production
Term
analgesia takes place how soon via brief-intense mode
Definition
instantaneously
Term
how long does analgesia last via brief-intense mode
Definition
hours after use
Term
pulse duration and pulse frequency of brief-intense mode
Definition
>150 microseconds, >80 Hz
Term
indications for TENS (4)
Definition
management of acute/chronic pain, post-operative pain, labor pains, other chronic pain syndromes
Term
this current is characterized by the crossing of 2 sinusoidal waves, each having similar but slightly different carrier frequencies which interfere with each other to produce an amplitude-modualted beat frequency
Definition
interferential current
Term
interferential current utilizes the strong physiologic effects of medium frequecy electrical stimulation of mm and nerve tissue without what associated side effects?
Definition
painful side effects
Term
IFC depoarlizes what nerves
Definition
peripheral sensory and motor nerve fibers
Term
IFC may have analgesic that is similar to, if not superior to what?
Definition
TENS
Term
Medium frequency devices are between what frequencies
Definition
1000 Hz-10,000 Hz)
Term
medium frequency devices are also known as what
Definition
carrier frequencies
Term
medium frequency devices are known to be tolerated well by teh body beacuse of what?
Definition
low skin impedance
Term
the skin's resistance is proportional to the frequency of the current how?
Definition
inversely proportional
Term
the skin's resistance is inversely proportional to the frequency of the current, meaning what for low current
Definition
greater resistance in the skin and patient discomfort
Term
Why can IFC comfortably penetrate deeper into the body
Definition
low skin impedance
Term
IFC: when two sinusoidal waves are in phase the sum of the two waves is large
Definition
constructive interfrence
Term
IFC: the sum of the two waves is zero when the waves are 180 out of phase
Definition
destructive interference
Term
the resultant frequency produces by the 2 waves repeatedly going in and out of phase
Definition
beat frequency
Term
beat frequency in which both carrier frequencies are fixed
Definition
constant
Term
beat frequency in which only one carrier frequency is constant
Definition
variable
Term
if both carrier frequencies are fixed, one being 4000 and the other 4100, what is the beat frequency
Definition
100 Hz
Term
in a constant beat frequency, the beat frequency is carried on what type of carrier frequency? assuming the original carrier frequencies are 4000 and 4100 respectively
Definition
medium carrier frequency of the 4050 Hz amplitude-modulated current
Term
a variable beat frequency is also known as what
Definition
sweep frequency
Term
Sweep/variable beat frequency is used to minimize what
Definition
accomodation
Term
in order to cause a tetanic contraction through sweep frequency, what must the beat frequency be (range)
Definition
90-150 Hz
Term
which beat frequency is capable of producing a tetanic contraction
Definition
variable/sweep beat frequency
Term
physiologic effects of IFC: 4
Definition
pain releif, stress incontinence, improved ciruclation, edema management
Term
How does IFC help with pain relief
Definition
Gate theory, opiate production
Term
What frquency should be used with IFC to utilize the gate theory of pain relief
Definition
higher beat frequency of 90-150 Hz
Term
What beat frequency should be used in opiate production for IFC
Definition
1-5Hz
Term
what should teh overall frequency and intensity be for pain relief through IFC
Definition
lower frequencies and lower intensities
Term
Stress incontinence through IFC does what to strengthen pelvic floor muscles
Definition
generate tetanic contractions
Term
how can IFC lead to improved circulation/edema mangament
Definition
IFC can lead to muscle pumping with the production of tetanic contraction
Term
what frequency is needed for the IFC to improve circulation/edema managament
Definition
>33 Hz
Term
in IFC where is the greatest concentration of current?
Definition
where the field intersect
Term
Selection of bipolar vs quadripolar IFC depends on wwhat
Definition
depth of the target tissue
Term
IFC: Pain Relief: Amplitude
Definition
submotor, a comfortable tingling sensation. No motor response
Term
IFC: Pain Relief: Pulse rate
Definition
50-110 bps (gate theory) or 1-10 bps (opiates)
Term
IFC: Pain Relief: pulse duration
Definition
50-100 microseconds
Term
IFC: Pain Relief: treatment time
Definition
15-60 minutes
Term
IFC: Muscle Strengthening of Pelvic Floor: amplitude
Definition
tetanic muscle contraction
Term
IFC: Muscle Strengthening of Pelvic Floor: pulse rate
Definition
35-50 pps (Hz)
Term
IFC: Muscle Strengthening of Pelvic Floor: pulse duration
Definition
125-500 microseconds
Term
IFC: Muscle Strengthening of Pelvic Floor: treatment time
Definition
depedent on number of reps/sets desired
Term
IFC indications (5)
Definition
pain modulation, muscle spasm, muscle reeducation, disuse atrophy, edema
Term
applicatio of a continuous direct current that is used to transfer medicinal agents through the skin for therapeutic purposes
Definition
iontophoresis
Term
Iontophoresis: acetate will require which electrode
Definition
cathode, as acetate is negatively charged
Term
Iontophoresis: dexamaethasone will require which electrode
Definition
cathode, as dexamethasone is negatively charged
Term
Iontophoresis: glucocorticoid will require which electrode
Definition
cathode, as glucocorticoid is negatively charged
Term
Iontophoresis: salicylate will require which electrode
Definition
cathode, as salicylate is negatively charged
Term
Iontophoresis: hydrocortisone will require which electrode
Definition
anode, as hydrocortisone is positively charged
Term
Iontophoresis: hyoluranidase will require what electrode
Definition
anode, as it is negatively charged
Term
Iontophoresis: lidocaine will require what electrode
Definition
anode, as it is positively charged
Term
Iontophoresis: zinc will require what electrode
Definition
anode, as zinc is positively charged
Term
Iontophoresis: effect and charge of acetate
Definition
(-), dissolves calcium deposits in soft tissues
Term
Iontophoresis: charge and effects of dexamethasone
Definition
(-) anti-inflammatory
Term
Iontophoresis: charge and effects of glucocorticoid
Definition
(-) antiinflammatory
Term
Iontophoresis: charge and effects of salicylate
Definition
(-) decreases local pain and inflammation
Term
Iontophoresis: charge and effects of hydrocortisone
Definition
(+) anti inflammatory
Term
Iontophoresis: charge and effects of hyoluronidase
Definition
(+) anti inflammatory
Term
Iontophoresis: charge and effects of lidocaine
Definition
(+) decreases local pain
Term
Iontophoresis: charge and effects of zinc
Definition
(+) enhances tissue healing
Term
Iontophoresis indications (6)
Definition
decrease pain, inflammation, edema, hyperhydrosis, softening of cutaneous tissue, bactericidal effects
Term
iontophoresis contraindicaitons (3)
Definition
same as other estim devices, skin irritation from the use of galvanic DC, allergy/hypersentivity to ions used
Term
Inteferential Current: Pulse rate for gate theory
Definition
50-110 bbps
Term
IFC pulse rate for opiate production
Definition
1-10 bps
Term
IFC pulse rate for pain relief
Definition
50-100 microseonds
Term
IFC pain relief treatment time
Definition
15-60 minutes
Term
IFC muscle strengthening of pelvic floor: amplitude
Definition
tetanic muscle contraction
Term
IFC muscle strengthening of pelvic floor:pulse rate
Definition
35-50 pps (Hz)
Term
IFC muscle strengthening of pelvic floor:pulse duration
Definition
125-500 microseconds
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