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Knee Surgery: The Placebo Effect?

by Dr. Julian Whitaker

Published 04/30/09

Knee pain is the most common reason for visits to orthopedic surgeons. However, if your doctor recommends arthroscopic knee surgery to alleviate the pain and stiffness of arthritis, I urge you to get a second opinion. Though the procedure is minimally invasive, it is also minimally effective. Arthroscopic surgery is performed by making small incisions in the skin, then inserting a tiny microscope into the joint space to inspect the region for damage. Small surgical instruments are used to trim cartilage, remove debris (a process called debridement), and clean the joint (a process called lavage or irrigation).

Over 200,000 of these operations are done on middle-aged and older adults to relieve pain and stiffness from arthritis. But guess what? Arthroscopic surgery is absolutely worthless for improving function in stiff, aching arthritic knees. This isn't just my opinion.

A placebo-controlled study published in the New England Journal of Medicine reached the very same conclusion. Placebo-controlled studies that compare drugs to look-alike "sugar pills" are quite common. However, subjecting people to the risks of surgery without actually performing the surgery is considered unethical. This study was designed with the help of an ethicist so that the risk to patients undergoing the placebo procedure would be minimized. Instead of receiving general anesthesia, they were simply given a drug that put them to sleep.

Patients signed a consent form indicating their willingness to participate, but they didn't know whether they would be getting actual arthroscopic surgery or a sham procedure. Even the surgeon didn't know whether he would be performing surgery or simply pretending to do so until after the patient was wheeled into the operating room and he opened a sealed envelope.

Patients randomly assigned to the surgical group underwent arthroscopic surgery, including lavage and debridement, if necessary. Those who were assigned to the placebo group had small incisions made in the knee identical to those made in the surgical patients' knees. Though no instruments were inserted, the surgeon asked for instruments and moved and bent the knee as if he were actually operating.

The patients' progress was followed for two years after the procedure. Though those who had undergone actual arthroscopic surgery claimed their knee pain had improved...and so did the patients who had not had surgery. And tests showed that the operation had not yielded any objective improvement in knee function at any time during the two-year period.

The bottom line: Arthroscopic knee surgery for arthritis pain and stiffness is unlikely to give you the results you want. Save your money and avoid the risk.