Diathermy Flashcards
Energy is transmitted by
- Oscillatory motion in the form of magnetic waves
- Propagated through space
Electromagnetic radiation consists of
- Alternating magnetic and electric fields varying over time
- Oriented perpendicular to each other
Both electric and magnetic fields are the consequence of
- Attraction and repulsion of electric charges
Magnetic effect is caused by
- Moving electric charges
Electric field is caused by
- Stationary electric charges
All EM waves travel through space at what speed
- 3x10^8 m/s
- Speed of light
Electromagnetic spectrum is composed of
- Various wave energies arranged in order
- Depicts EM waves
EM spectrum is grouped acc to
- Wavelength
- Frequency
- Energy
Wave length is defined as
- Distance from peak of one wave to peak of another
- Can be in nm or m
Enumerate EM waves on EM spectrum in order from widest to narrowest
- Radio
- Microwave
- Infrared
- Visible
- Ultaviolet
- Xray
- Gamma ray
Wavelength is ______ proportional to frequency.
- inversely
Energy unit of measurement
- Electron volt
Energy of photon is computed by
- Frequency x plank’s constant
Ionization is process of
- Removing ion from orbit
(Ionizing/non-ionizing) can cause harm
ionizing
What waves are under non-ionizing
- Radio
- Microwave
- Infrared
- Visible
- UV (the wider waves)
If ionization is > ? Then it is ionizing agents
10 electronvolt
Fates of em waves
- Reflected
- Refracted
- Transmitted
- Absorbed
Diathermy is what wave
- Lower frequency Radio and microwaves
Diathermy uses ___ as energy transfer
- Radiation
Diathermy means
- To heat through
Who first used diathermy and when
- 1892
- Jacques arsene d arsonval
Diathermy is the use of ___ and ___ waves that produces heat
- Shortwave
- Microwave
Diff types of diathermy
- Longwave
- Shortwave
- Microwave
Long wave is still being used. T or F.
False
Shortwave wavelength
- 30-3 m
Shortwave frequency
- 10-100 mhz
Microwave wavelength
- 3-0.03 m
Microwave frequency
- 300 mhz-300 ghz
Frequency bands of shortwave
- 13.56 mhz
- 27.13 mhz
- 40.68 mhz
Most commonly used frequency band of shortwave
27.13 mhz
Most commonly used frequency band of shortwave
- 27.13 mhz
Microwave diathermy frequency bands
- 433.9 mhz
- 915 mhz
- 2450 mhz
Most commonly used microwave frequency band
- 2450 mhz
Factors that affect absorption
- Amount of energy
- Tissue type
SWD heats deeper vs superficial. T or F.
True
Ultrasound can heat a larger surface area than SWD. T or F.
False
SWD is harmful to periosteum. T or F.
False
SWD heat focuses most on
soft tissues
MWD has reflection of radiation. T or F.
True
MWD heat is concentrated on
fat
MWD penetrates the shallowest and therefore focuses on more superficial. T or F.
False, penetrates deepest but focuses on superficial.
With SWD, there is danger of overheating fats. T or F.
False, it is MWD.
Thermal effects are achieved in
continuous mode
thermal effects of daithermy (8)
- Pain control
- Inc tissue healing
- Inc blood flow
- Inc metabolism
- Dec joint stiffness
- Inc collagen extensibility
- Muscle relax
- In conjunction w stretching to inc rom
non thermal effects (5)
- Inc microvascular perfusion (better deliver of oxygen to tissues) - wound healing
- Modulates cell growth and division
○ Can accelerate if slow and inhibit if fast - Accelerates calcium binding to calmodulin
○ Calmodulin activates cross brisges - Inc rate of phagocytosis
Inc atp activity
- Modulates cell growth and division
Two methods of applying SWD
- Capacitive plates/ electric field method
- Inductive coils/magnetic field
Method of applying MWD
- Magnetron (condenser)
Capacitive plates is made of
- Metal encased in plastic housing or carbon rubber electrodes
How does electric field method work?
Current flows from one plate to other (there are 2 plates), produces an electric field
Techniques of application for capacitive plates
- Contra-planar/ transverse positioning
○ Sandwich tissue in between plates- Coplanar positioning
○ Apply parallel on same body surface
- Coplanar positioning
More heating will occur on plate nearer to tissue. T or F.
T
Diff types of electrodes/condensers
- Plates
- Pads
Distance between electrodes and skin should be
- 1-3 inches
In capacitive plates heating occurs mostly on
- Tissues with conductivity
○ Muscle- Produces more heat on superficial tissues
Fats can block effectivity of capacitive plates. T or F.
True
Inductive coil/magnetic field method
- AC produces magnetic field
- Induces electrical eddy currents in tissues
- Oscillation of charged particles
- Friction generates heat
Types of electrodes
- Drums ○ Diplode ○ Monode - Sleeves with cables ○ Circumferential on limbs
Inductive coils heats which part the most
- Tissues with highest conductivity
○ Muscles- Heats tissues closest to applicator
Fat is not an issue when it comes to inductive coils. T or F.
True
Distance for inductive coil
slight air gap
Factors affecting field distribution in shortwave
- Spacing
○ Closer = more superficial- Electrode size
○ Smaller = more superficial
- Electrode size
Magnetron (condenser)
- Produces high frequency AC in antenna to create em field
- Microwave
Magnetron is used for
- Smaller more defined areas
Tissue heating effect of magnetron
- Most heating occurs on tissues with highest conductivity
- Focus on relatively superficial structures (skin and fat)
Distance of magnetron
- Few inches
Inductive coil heating on fat, muscle, and bone
- Fat: minimum
- Muscle: maximum
- Bone: none
Capacitive plate heating on fat, muscle, and bone
- Fat: maximum
- Muscle: moderate
- Bone: low
Magnetron heating on fat, muscle, and bone
- Fat: maximum
- Muscle: maximum
- Bone: none
Ultrasound heating on fat, muscle, and bone
- Fat: slight
- Muscle: maximum
- Bone: none
Dose 1
- Non thermal
- Acute injuries
Dose 2
- Mild heat
- For sub acute
Dose 3
- Moderate comfortable heat
- Pain muscle spasm, chronic inflammation
Dose 4
- Vigorous
- Blood flow increase, heating of collagen fibers for stretching
Thermal indications
- Pain control
- Accelerate tissue healing
- Decrease joint stiffness
- Increase soft tissue extensibility
non-thermal indications
- Pain and edema due to modification of cell membrane function
- Soft tissue healing
○ Inc collagen formaiton
○ Inc white blood cell infiltration
○ phagocytosis - Nerve and bone healing on animal studies
- Soft tissue healing
Contraindications
- Pacemakers
- Electronic implants
- Metal implants
- Malignancies
- Thrombophlebitis
- Over abdomen, low back, or pelvis of pregnant women
Contraindications for only thermal
- Eyes or testes
- Over growing epiphyses
- Hemorrhage
- Contact lenses
- Deep tissues (internal organs)
Precautions
- External electronic medical devices nearby should be 3-5 m away from diathermy
- Copper bearing intrauterine device
- Obesity
- Impaired sensation or circulation
- Decreased consciousness
- Over moist clothes or accumulated sweats
- Over atrophic, infected, or damaged skin
- (PSWD) Over growing epiphyses of children, for everything else it’s a contraindication
- Excessive exposure of pt to radiation
○ Stay 1-2 m away from continuous
0.5-1m for pulsed
Adverse effects of diathermy
- Burns or blistering
Documentation
- Continuous SWD x distance x duration on treatment area to rationale
- Pulsed SWD x distance x duration x (how many times a day) on treatment area to rationale
Most commonly used dosage
- Between 2 and 3
- Mild comfortable dry heat
