Types of Ultrasound Therapy
There are two main types of ultrasound therapy: thermal and mechanical. Both use sound waves generated through a transducer head (which looks a bit like a microphone) to penetrate soft tissues. The difference between the two types of ultrasound therapy is the rate at which the sound waves penetrate the tissues.
Thermal ultrasound therapy. Thermal ultrasound therapy uses a more continuous transmission of sound waves. The sound waves cause microscopic vibrations in the deep tissue molecules, increasing heat and friction. The warming effect encourages healing in the soft tissues by increasing the metabolism at the level of the tissue cells.
Mechanical ultrasound therapy. Mechanical ultrasound therapy uses pulses of sound waves to penetrate tissues. While this still has a minor warming effect on the tissues, it also causes expansion and contraction in the tiny gas bubbles of the soft tissues. This helps to decrease the inflammatory response, reducing tissue swelling and thus decreasing pain.
The type of ultrasound therapy you receive depends on your condition. If you have myofascial pain, or had a muscle strain or sprain that has not healed, your therapist will likely use thermal ultrasound therapy. If your pain is caused by scar tissue or swelling, such as with carpal tunnel syndrome, you may benefit more from mechanical ultrasound therapy.
How Ultrasound Therapy Is Performed
Your therapist will select a small surface area to work on for anywhere from five to 10 minutes. Gel is applied either to the transducer head or to your skin, which helps the sound waves evenly penetrate the skin. During your ultrasound therapy treatment, your therapist will continually move the transducer head over and around the selected area.