Therapeutic ultrasound for osteoarthritis of the knee or hip

Rutjes AWS, Nüesch E, Sterchi R, Jüni P

Summary

Therapeutic ultrasound for osteoarthritis

This summary of a Cochrane review presents what we know from research about the effect of therapeutic ultrasound on knee or hip osteoarthritis. The previous version of this review concluded that therapeutic ultrasound had no benefit over fake therapeutic ultrasound in pain relief and functional status.

The updated review shows that in people with osteoarthritis,
-Therapeutic ultrasound may be beneficial for people with osteoarthritis of the knee.

-Therapeutic ultrasound may improve your physical function but this finding could be the result of chance.

- We are uncertain about the magnitude of effects on pain relief or the ability to use your knee, because of the low quality of the evidence.
-Therapeutic ultrasound may not have any side effects: no side effects were reported, but we do not have precise information about side effects. This is particularly true for rare but serious side effects. 

There are no studies that address the benefits of therapeutic ultrasound in people with hip osteoarthritis.

What is osteoarthritis and what is therapeutic ultrasound?

Osteoarthritis is a disease of the joints, such as your knee or hip. When the joint loses cartilage, the bone grows to try and repair the damage. Instead of making things better, however, the bone grows abnormally and makes things worse. For example, the bone can become misshapen and make the joint painful and unstable.  This can affect your physical function or ability to use your knee.
Therapeutic ultrasound means using sound waves to try and relieve pain or disability. Your doctor or physiotherapist will use a round-headed wand or probe on the skin of the painful area. Ultrasound gel is used on the wand and on your skin to make it more comfortable and help the sound waves reach the affected area. 

Best estimate of what happens to people with osteoarthritis who have had therapeutic ultrasound for a duration of 2-8 weeks:

Pain
-People who used therapeutic ultrasound had an improvement in their pain of about 3 on a scale from 0 (no pain) to 10 (extreme pain) after using it up to 2 months.
-People who used a fake therapeutic ultrasound had an improvement in their pain of about 2 on a scale from 0 to 10 after using it up to 2 months.
Another way of saying this is:
- 37 people out of 100 who use therapeutic ultrasound respond to treatment (37%).
- 31 people out of 100 who use fake therapeutic ultrasound respond to treatment (31%).
- 6 more people respond to treatment with therapeutic ultrasound than with fake therapeutic ultrasound (difference of 6%).