Therapeutic ultrasound is a treatment commonly used in physical therapy to provide deep heating to soft tissues in the body. These tissues include muscles, tendons, joints, and ligaments.
Ultrasound in physical therapy is different than diagnostic ultrasound. With the latter, healthcare providers use ultrasound to see the inside of the body. For example, diagnostic ultrasound lets healthcare providers check on a fetus during pregnancy.
What Is Therapeutic Ultrasound?
Therapeutic ultrasound is used to heat tissues and introduce energy into the body.1
Deep Heating Effects
Ultrasound can provide deep heating to soft tissue structures in the body. Deep-heating tendons, muscles, or ligaments could have the following benefits:
Increase circulation to tissues
Speed the healing process
Decrease pain
Increase elasticity
If you have shoulder pain and have been diagnosed with a frozen shoulder, your physical therapist (PT) may use ultrasound. This therapy is usually done before performing a range of motion exercises because it can help improve the ability of your shoulder to stretch.
How Does Ultrasound Work?
Inside your physical therapist’s ultrasound unit is a small crystal. When an electrical charge hits this crystal, it vibrates rapidly, creating piezoelectric waves (an electric account accumulating in some solid materials). These waves emit from the ultrasound sound head as ultrasound waves.
During treatment, the ultrasound wave then enters your injured tissues. This exposure to ultrasonic waves increases blood flow and cavitation, leading to the theorized benefits of the treatment.
When Is It Used?
PTs may use therapeutic ultrasound to treat some injuries and chronic pain.
Injuries
Usually, PTs treat orthopedic (musculoskeletal) injuries with ultrasound. These may include:
Bursitis (inflammation in the fluid-filled sacs along joints)
Tendonitis
Muscle strains and tears
Frozen shoulder
Sprains and ligament injuries
Joint contracture or tightness
Generally speaking, any soft-tissue injury in the body may be a candidate for ultrasound therapy. For example, your physical therapist may use ultrasound for low back pain, neck pain, rotator cuff tears, knee meniscus tears, or ankle sprains.
Chronic Pain
There is also some evidence that you may benefit from ultrasound treatments if you have chronic pain. It is thought that ultrasound waves help improve tissue extensibility and circulation, leading to increased mobility and, ultimately, decreased pain.
