Patients experiencing chronic musculoskeletal pain may receive a referral from a physician for ultrasound therapy performed by a physical therapist or occupational therapist. Others who may offer ultrasound therapy include athletic trainers, practitioners of manipulation therapy such as chiropractors, and (less commonly) speech language pathologists, who may use it for certain types of swallowing problems (dysphagia).

Before administering this form of thermotherapy or diathermy, the practitioner will likely obtain a medical history and conduct a physical examination or similar evaluation, as thermotherapy is recommended for particular conditions.

Patients may be asked to describe the pain in detail. They may also be given a pain assessment, such as a diagram of the body and asked to mark areas where they are experiencing pain. Questions to assess the pain may include:

• Can you describe the pain?
• Where does the pain occur?
• How long have you experienced the pain?
• Have you experienced this type of pain in the past?
• Is the pain constant, or does it come and go?
• Are there any movements that make the pain worse?
• Do you have limited movement?
• Have you ever had thermotherapy for the same condition or any other disorder?

In some cases ultrasound therapy may be used after other modalities, such as a hot pack, cold pack (cryotherapy) or electrical therapy.

Depending on the area being treated, the patient may sit in a chair or lie on a padded table during the procedure. Articles of clothing and jewelry may need to be removed. Sometimes it is necessary for patients to change into a hospital gown.

The therapist will cleanse the area to be treated and apply a coupling agent, such as an ultrasound gel, to provide effective conduction between the ultrasound head (transducer) and the skin. Sometimes a physician prescribes phonophoresis, the use of ultrasound to introduce topical medications (such as a corticosteroid, analgesic or anesthetic) through the skin.

The frequency, intensity and duration of treatment depend on the individual condition. The practitioner will place the head of the ultrasound machine on the area being treated and move it in small circular motions. The ultrasound head must be moved continuously over the treatment site to avoid hot spots and burns.

The transducer should not be placed over a draining wound or the eyes, skull, spinal cord (which may be exposed after some types of spinal surgery), heart, reproductive organs or a pacemaker or other active implanted device. Depending on instructions from the physician, in some cases it may be used with caution near static metal implants such as a joint replacement (arthroplasty). Direct spinal application of ultrasound is also avoided in people who have had back surgery.

The ultrasound waves can be applied in two modes: continuous or pulsed. During continuous mode, the beam of ultrasound the patient receives is constant. With pulsed mode, the waves are transmitted in short or intermittent transmissions that prevent the tissues from heating but still provide mechanical effects such as greater permeability of cell walls.

During the procedure, the patient should experience a comfortable heating or no sensation at all. Treatment time varies according to the injury or condition, but usually lasts between five and 10 minutes.

Afterward, the patient may resume daily activities according to the therapist’s or physician’s orders. The procedure is often followed by exercise therapy or practice with activities of daily living (ADLs) to increase the patient’s range of motion and function.

As with most forms of physical or occupational therapy, patients have numerous visits over a period of time. Duration of treatment depends on the condition being treated as well as the treatment plan outlined by the therapist. Progress may be tracked with assessment tools such as a pain scale or a goniometer, a protractor-like device that measures joints’ range of motion.