Diathermy is a part of a complete physiotherapy regimen. The frequency and length of the treatments vary.
Frequency: Shortwave diathermy uses a frequency ranging from 3 to 30MHz Usually a frequency of 27.12 MHz and a wavelength of 11 meters is used. Currents of such high frequencies do not stimulate sensory or motor nerves nor do they produce any muscle contraction. Shortwave diathermy can either be
- Continuous shortwave diathermy (CSWD).
- Pulsed shortwave diathermy (PSWD).
Continuous short-wave diathermy: has a thermal effect more than pulsed, so it is generally used for its thermal effects whereas
pulsed short-wave diathermy has athermal effects. Shortwave diathermy uses high-frequency electromagnetic energy to generate heat, in pulsed or continuous energy waves.
Electrodes: The current is applied to the patient by a heavy, flexible, insulated cable which is used as the electrode and is coiled about or around the patient’s part to be treated.
There are two methods of application of electrode pads,
Contra planar electrode placement: The two electrodes are placed in two different planes, therefore it is called contra planar. the two pads sandwich the treating body part between them.
Coplanar electrode placement: In contra planar arrangement, the pads are placed side by side on the same plane. This is used to treat large body parts such as the upper back. lower back. The electrodes should not be placed too close as the wave path does not go deeper.