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  5. Ultrasonic Therapy Product or Ultrasonic Diathermy
  1. Surgical and Therapeutic Products

Ultrasonic Therapy Product or Ultrasonic Diathermy


Ultrasonic therapy or ultrasonic diathermy products used in physical therapy equipment produce high-frequency sound waves that travel deep into tissue and create gentle therapeutic heat. Ultrasonic diathermy is intended to generate deep heat within body tissues for the treatment of selected medical conditions such as pain, muscle spasms and joint contractures, but not for the treatment of malignancies.

The sound waves are transmitted through a round-headed wand that the therapist applies to the skin with gentle, circular movements. A hypo-allergenic gel aids in the transmission of the ultrasonic energy and prevents overheating at the surface of the applicator.

Treatments usually last between five and 10 minutes.

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Ultrasonic therapy does not hurt (there may be a bit of a tingling sensation and/or a sensation of warmth) if the therapist keeps the wand moving continuously. If, however, the wand is held in place for more than a few seconds, it can become uncomfortable at higher energies.

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Information for Patients

While ultrasonic therapy can be used to treat the conditions described above, it is important to know that there are situations and areas of the body where it cannot safely be used. You should notify the practitioner administering the ultrasound if any of the following applies to you:

  • You have a cardiac pacemaker
  • You have a malignancy in the area to be treated
  • You have a healing fracture in the area to be treated
  • You are pregnant
  • You have an implanted medical device other than a pacemaker such as implanted deep brain stimulation device

You should also be aware that commercial ultrasonic diathermy devices may exist that have not been formally evaluated by FDA. Typically, these devices will claim to treat a range of diseases, disorders, and have other uses that are not covered in the description above (for example, to reduce wrinkles on the face).

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Information for Professionals

Over the years, FDA has evaluated a number of ultrasonic diathermy devices. They are all capable of heating deep tissue to a therapeutic temperature range of 40-45°C for the selected conditions described above. However, there are various configurations with regard to energy output and applicator size. Furthermore, there may be instructions that apply only to a particular device. Therefore, it is important that you read and be familiar with the instructions for the particular device that you use. You should also be especially mindful of all contraindications, warnings, and precautions that apply to the device.

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Laws, Regulations, & Performance Standards

Manufacturers of electronic radiation emitting products sold in the United States are responsible for compliance with the Federal Food, Drug and Cosmetic Act (FFDCA), Chapter V, Subchapter C - Electronic Product Radiation Control.

Manufacturers of ultrasonic therapy products are responsible for compliance with all applicable requirements of Title 21 Code of Federal Regulations (Subchapter J, Radiological Health) Parts 1000 through 1005:

1000 - General

1002 - Records and Reports

1003 - Notification of defects or failure to comply

1004 - Repurchase, repairs, or replacement of electronic products

1005 - Importation of electronic products

In addition, ultrasonic therapy devices must comply with radiation safety performance standards in Title 21 Code of Federal Regulations (Subchapter J, Radiological Health) Parts 1010 and 1050.10:

1010 - Performance standards for electronic products: general

1050.10 – Ultrasonic Therapy

Because they are medical devices, ultrasonic therapy products must also comply with the medical device regulations. For more information, see Getting to Market with a Medical Device.

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Reporting Forms

Other Resources

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