electrotherapy foundations Flashcards
definition: loss/gain of electrons
charge (C or mC)
definition: attraction/repulsion forces that create an electric field
polarity (cathode or anode)
definition: driving force that moves electrons; a measure of potential energy
voltage (volt or millivolt)
What are examples of conductors?
water, metal, nerves
What are examples of insulators?
rubber, plastic fat
definition: movement of ions/electrons in response to voltage force that is directly proportional to the magnitude of voltage
current (amp or A)
According to Ohm’s law, increased current will (decrease/increase) the strength of the contraction and (decrease/increase) the strength of sensation
increase, increase
The current will always follow the path of (least/most) resistance
least
definition: the degree to which an electrical charge is stored in a system containing conductors and insulators
capacitance
definition: resistance to the flow of alternating current
impedance
(gels and adhesives work to decrease impedance by improving the connection between the electrode and the skin)
definition: continuous undirectional flow of electrons for at least 1 second
- flow from positive to negative or negative to positive
direct current
definition: the direction of flow stops after 1 second and then resumes in the SAME direction for 1 second
interrupted direct current
definition: when flow stops after 1 second and resumes in the OPPOSITE direction for at least 1 second
reversed direct current
definition: uninterrupted, bi-directional flow of electrons, that change direction at least one time per second
alternating current
Alternating current (is/is not) interrupted
is not
Direct current (is/is not) interrupted
is
definition: uni-directional or bi-directional flow of electrons that periodically ceases for a short time period
pulsed current
definition: pulsed current where all pulses are on the same side of the x-coordinate… produced from intermittently interrupting a direct current source
monophasic
definition: pulsed current where pulses are on the opposite sides of the x-coordinate… produced from intermittently interrupting an alternating current source
biphasic
The body is mostly ___ water
salt
With E-stim, NaCl- (separates, attracts)… Na+ attracts to (cathodes/anodes) and Cl- attracts to (cathodes/anodes) and combine with water
separates into Na+ and Cl-, cathodes, anodes
definition: energy is neither created nor destroyed but rather exchanged, and through the exchange, some energy is lost in the form of heat
law of thermodynamics
What voltage are nerves depolarized at?
-70 mV
What voltage are muscles depolarized at?
-90 mV
Gate control theory:
Stimulation of the ___ fibers inhibits the substantia gelatinosa and results in the gate opening and the pain message traveling to the brain.
A-delta, C- fibers
What therapeutic current is used for strengthening muscles?
russian current
Russian current is a variation of ______ current.
alternating
What therapeutic current is used for pain modulation, tissue repair, and wound healing?
high volt pulsed current (monophasic pulsed current)
What therapeutic current is primarily used for pain modulation?
interferential current (IFC)
definition: alternating biphasic current that is interrupted and delivered in short bursts
russian current
What direct current is used for tissue repair and wound healing?
low intensity Direct current (microcurrent)
(true/false) Low-intensity DC (microcurrent) stimulates sensory/motor nerves
false
definition: any current with < 1 mA
microcurrent
What pulsed current is used for muscle stimulation and pain modulation?
symmetrical/asymmetrical biphasic pulsed current
Small electrodes are used for (less/more) current density compared to large electrodes
more
(small/large) electrodes have a better selectivity.
small
(small/large) electrodes provide a more painful contraction
small
(small/large) electrodes provide a stronger contraction WITHOUT pain
larger
A patient will get a greater current spread with the electrodes being placed (closer/further away) from each other
further away
What electrode setup is commonly used for wound healing, edema, and iontophoresis?
monopolar (single electrode with dispersive electrode)
What electrode set up is commonly used for muscle activation and pain modulation?
bipolar
What electrode setup is used primarily for pain modulation?
quadripolar
What are precautions for electrotherapy?
- poor skin condition
- excessive swelling
- excessive adipose
- avoid carotid artery
- phrenic nerve
- PVD
- implanted devices
What are contraindications for electrotherapy?
- pacemakers
- pregnancy
- poorly controlled epilepsy
- acute DVT
- complete peripheral nerve lesion
- Cancer
- infection
