What is the principal function of diathermy?

The principal function of diathermy is thermal treatment through energy. Diathermy is a therapeutic modality that uses high-frequency electrical currents to generate heat within the body tissues. This heat can promote increased blood circulation, relieve pain, and facilitate healing processes in muscles and joints. The mechanism by which diathermy operates involves either microwave or shortwave frequency, which is applied to targeted areas to create deep tissue warmth.

In the context of other options, while skin tightening could be an effect of heat therapy, it is not the main function of diathermy. Similarly, while some energy-based treatments might be involved in hair removal, diathermy’s primary application is not in this area. Skin cleansing does not relate to the thermal aspect of diathermy, as it focuses more on superficial effects rather than the deeper thermal treatments that diathermy provides. Thus, the emphasis on thermal treatment through energy accurately captures the essential purpose of diathermy.