What does diathermy refer to?

Diathermy is a therapeutic treatment that involves generating heat within body tissues. This process typically uses high-frequency electromagnetic currents, which generate heat as they pass through the tissues, thereby enhancing blood flow and promoting healing. The heat produced can help alleviate pain, reduce stiffness, and improve mobility by increasing circulation and relaxing muscles.

The other options do not accurately describe diathermy. While physical therapy techniques may include various forms of treatment for rehabilitation, they do not specifically focus on generating heat within tissues like diathermy does. Electrical stimulation therapy also uses different modalities to stimulate nerves and muscles but does not inherently involve generating heat within the tissues. Lastly, deep tissue massage is a manual therapy focused on physical manipulation of the body rather than the mechanical generation of heat through tissues. Therefore, the definition of diathermy is clearly aligned with the concept of generating heat through tissues, making that the correct choice.