Ultrasonic waves or sound waves of a high frequency that is not audible to the human ear are produced by means of mechanical vibration in the treatment head of the ultrasound machine. The treatment head is then moved over the surface of the skin in the region of the injury transmitting the energy into the tissues. When sound waves come into contact with air it causes a dissipation of the waves, and so a special ultrasound gel is placed on the skin to ensure maximal contact between the treatment head and the surface of the skin and to provide a medium through with the sound waves can travel.
The sound waves that pass through the skin cause a vibration of the local tissues. This vibration or cavitation can cause a deep heating locally, though usually no sensation of heat will be felt by the patient. In situations where a heating effect is not desirable, such as a fresh injury with acute inflammation, the ultrasound can be pulsed rather than continuously transmitted.
- Deep heating to tissue– muscles, tendons, joints, and ligaments which leads to a reduction in inflammation and tension.
- Reduce the healing time of certain soft tissue injuries.
- Local blood flow – helps reduce local swelling and chronic inflammation.
- Scar tissue breakdown