Is shock therapy safe for Jumpers Knee?

Q: I've been told that I might get some benefit from "shock therapy" to my knee for a bad case of "Jumper's Knee." Is this really a safe method of treatment?

A: Running and jumping over and over often leads to a condition in athletes known as or jumper's knee (also known as patellar tendinosis. Pain along the front of the knee during the activity that goes away with rest is a cardinal symptom of this condition. Dancers, gymnasts, and basketball, soccer, and volleyball players are affected most often.

There is a simple treatment for this problem. Jumper's knee goes away when the muscles along the front of the knee (extensor mechanism) that pull across the patella (kneecap) stop pulling. It is a self-limiting, self-resolving condition. Therefore, the first recommended treatment is always to stop overloading the extensor mechanism. Rest, anti-inflammatory medications, and specific exercises under the supervision of a physiotherapist are advised.

If a conservative plan of care fails to yield the desired results, then other options may be considered such as extracorporeal shock wave therapy (ESWT). ESWT is a way to generate sound waves outside the body that can be focused at a specific site within the body (in this case, the knee). This treatment technique is also referred to as pressure or sound wave therapy. It is a noninvasive, outpatient procedure.

Pressure waves travel through fluid and soft tissue to sites where there is a change in tissue density. A common interface is where the soft tissues meet bone. A special device delivers shockwaves to the target point where treatment is needed. The shockwaves break down scar tissue that has built up. The body's repair mechanisms are stimulated to promote healing. New blood vessels develop in the injured area to help jump start the healing process.

Another newer approach to the problem of Jumper's Knee is a blood injection therapy called platelet-rich plasma or (PRP). PRP refers to a sample of serum (blood) plasma that has four (up to 10) times more than the normal amount of platelets and growth factors. This treatment enhances the body’s natural ability to heal itself and is used to improve healing and shorten recovery time from acute and chronic soft tissue injuries.

Both treatments focus on the failed healing of the overused tendon by promoting cell growth, release of growth factors, and improving tissue remodeling. Both have been shown effective in the short term (e.g., first two months) but platelet-rich plasma may have better mid-term results. Further study is needed to assess long-term results. You may want to discuss both of these treatment options with your orthopedic surgeon and find out what might be best for you given your particular circumstances.

Reference: Mario Vetrano, MD, et al. Platelet-Rich Plasma Versus Focused Shock Waves in the Treatment of Jumper's Knee in Athletes. In The American Journal of Sports Medicine. April 2013. Vol. 41. No. 4. Pp. 795-803.