Ultrasonic waves or sound waves of a high frequency that are not audible to the human ear are produced by means of mechanical vibration in the metal treatment head of the ultrasound unit. 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, therefore, a special ultrasound gel is placed on the skin to ensure maximal contact between the treatment head and the surface of the skin. This also provides a medium through with the sound waves can travel.

The benefits of electrotherapy are wide-ranging and include pain reduction, soft tissue relaxation, improved blood flow, scar tissue breakdown and increased tissue tensile strength; all leading to an increase in range of movement.

Generally, injuries that have caused swelling will respond well to electrotherapy; these include sprained ankles and overuse injuries such as tennis and golfer’s elbow.