3. DIATHERMY: MEANS THROUGH HEATING.
Based on frequency & wave length it’s divided into 3 types
SHORT WAVE
MICROWAVE
LONGWAVE
DEFINITION: Application of high frequency non ionizing electromagnetic energy
to generate heat in deep tissues.
Frequency: 107-108HZ
Wave Length: 30-3mts
USES :
Musculoskeletal
Neurological
INTRODUCTION
Therapeutically used: 27.12MHZ at 11mts
40.68MHZ at 7.5mts
13.56MHZ at 22mts Rarely used
7. PRODUCTION
WORKING
Circuit
primary coil of Step
up & step down
transformer
Induces EMF in
secondary coil (step
up 4000volts & step
down 20-25 volts
Current flows from
step down to filament
which causes
thermionic emission
Flow of current from
filament to anode
Anode to oscillator
coil CD , induces
EMF in AB which is
connected to grid
Grid becomes –ve ,
no flow of current
Self induced EMF ,
charging of
condenser
Discharge in direction
D to C, induced EMF
AB
Grid becomes neutral Flow of current
Induces EMF in
resonator coil EF
Flow of currentPatient circuit
8. PHYSIOLOGICAL EFFECTS
Thermal Effects
Non Thermal
Effects
Non Thermal Effects
Increased microvasculature
perfusion
Activation of fibroblast
Increased macrophagic activity
9. PHYSIOLOGICAL EFFECTS
Direct Thermal Effects
Increased metabolism
Increased blood supply
Effects on nerves
Indirect Thermal
Effects
Muscle tissue
General raise in temperature
Fall in B.P
Increased activity of sweat glands
14. CONTRAINDICATIONS
Open Wounds
Metal In Tissue
Altered Skin Sensation
Venous Thrombosis
Arterial Disease
Menstruation
Pregnancy
Tumours
Exposure To Radiation
Unconscious
Children
Mentally Retarted
15. DANGERS
Burns
Scalds
Electric shock
Over dosage
Precipitation of gangrene
Fainting
Giddiness
Dangers to other equipment
Damage to hearing aids, pacemaker
16. METHOD OF APPLICATION
CONDENSOR/CAPACITOR METHOD
Creates strong electric field
Electrodes & patient tissue forms
capacitance
Depends on:
Size of electrode
Distance between electrodes
Tissue between electric field
CABLE METHOD
Creates strong magnetic field
Cable & patient tissue forms
inductance
EFFECT OF ELECTRICFIELD
Condenser: Rapid oscillation of electrons produce heat
Insulator: Distortion of molecules
Electrolyte : Rotation of dipolar
EFFECT OF ELECTRICFIELD ON BODY
Low Impedance: High dielectric constant
(Blood, Muscle)
High Impedance: Low dielectric constant
(Fat)
17. CAPACITOR METHOD
TYPES OF ELECTRODES
1. Pad
2. Plate
3. Disc
SIZE OF ELECTRODES
1. Different Size
2. Little Large
3. Smaller
4. Far Larger
Tuning :
Adjusting of variable condenser to equalise currents in
machine & patient circuit.
18. CAPACITOR METHOD
SPACING OF ELECTRODES
1. Small : Blood & muscle get heated up
2. Large : fat gets heated up
3. Narrow: superficial heating happens
4. Unequal
5. Wide: deep structures heated up
POSITION ELECTRODES
1. Coplanar
2. Contra planar
3. Mono planar
4. Cross fire
19. CABLE METHOD
Electric field: ends, used for high impedance
Magnetic field : centre used for low
impedance
Electrostatic field: capacitor method( low
impedance)
Method s
Helix
Grid
20. REFERENCES
CLAYTONS ELECTROTHERAPY
THERAPEUTIC FOR SPORTS MEDICINE AND ATHLETIC TRAINING MODALITIES BY W
I L L I A M E . P R E N T I C E
ELECTROTHERAPY BY JEGMOHAN SING