What is ultrasound therapy
Ultrasound therapy uses sounds of a high frequency and intensity that are converted to mechanical and heat energy. The treatment is administered by placing the application head of the device in continuous or pulse application onto the skin, which has been given a coating of conductive gel. In some cases, the ultrasound treatment may be performed in a water container, where both the treated body part and the device head are placed under water. The depth of impact varies between 2-6 cm. The site, mode, length and frequency of application must be prescribed by a doctor. The treatment procedure may be delivered by a physiotherapist or a trained nurse and usually lasts up to 12 minutes.

How ultrasound therapy helps
About one third of the ultrasound energy is absorbed in the molecules and results in a type of micro-massage in the targeted tissues, warming them up. This brings about muscle relaxation as well as improved blood circulation and tissue metabolism. Subsequently, pain, stiffness and swelling are reduced. The ultrasound waves further enhance certain chemical reactions in the connective tissues that lead to the better healing of bruises and the softening of stiff tissues.

Advisable for:

Chronic inflammation, pain or swelling of all connective tissues (joints and their capsules, ligaments, tendons, muscles), healing of bruises and sprained joints, chronic stiffness of sinews (Dupuytren’s contractures, Achilles tendon), peripheral blood circulation disorders (Raynaud, Buerger, and Sudeck diseases), hard skin scars

Not advisable for:

Acute injury or bruise up to 72 hours from its occurrence, any acute inflammation, metallic implant at the site of application (pacemaker, screws, joint replacements), infectious diseases, fever, untreated or uncontrolled hypertension, acute thrombosis, leg ulcers and other skin defects at the site of application, abdomen during menstruation, endometriosis, shortness of breath, pregnancy, psychosis, alcohol or drug abuse, malignant tumours (at the site of application, elsewhere possible), blood disorders, incapacitation

What is therapeutic ultrasound?

Therapeutic ultrasound is a modality that has been used by physical therapists since the 1940s. Ultrasound is applied using a round-headed wand or probe that is put in direct contact with the patient’s skin. Ultrasound gel is used on all surfaces of the head in order to reduce friction and assist in the transmission of the ultrasonic waves. Therapeutic ultrasound is in the frequency range of about 0.8-3.0 MHz.

The waves are generated by a piezoelectric effect caused by the vibration of crystals within the head of the wand/probe. 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.

Ultrasound can produce many effects other than just the potential heating effect. It has been shown to cause increases in tissue relaxation, local blood flow, and scar tissue breakdown. The effect of the increase in local blood flow can be used to help reduce local swelling and chronic inflammation, and, according to some studies, promote bone fracture healing. The intensity or power density of the ultrasound can be adjusted depending on the desired effect. A greater power density (measured in watt/cm² is often used in cases where scar tissue breakdown is the goal.

Ultrasound can also be used to achieve phonophoresis. This is a non-invasive way of administering medications to tissues below the skin; this is perfect for patients who are uncomfortable with injections. With this technique, the ultrasonic energy forces the medication through the skin. Cortisone, used to reduce inflammation, is one of the more commonly used substances delivered in this way.