Common surgery for knee arthritis receives stiff competition from placebo effect

~Note: this research study is from 2002. Old news. Still relevant.~

HOUSTON – (July 11, 2002) – Patients with knee osteoarthritis who undergo placebo arthroscopic surgery report the same amount of pain relief and improved mobility as those who undergo the real procedure. The landmark study appears as the lead article in the July 2002 issue of the New England Journal of Medicine.

Researchers at the Baylor College of Medicine collaborated with Houston’s Department of Veteran Affairs to recruit 180 patients, aged 75 years and under, experiencing knee pain, stiffness, or swelling; all symptoms of osteoarthritis, a degenerative joint disease. Baseline characteristics across groups such as race, sex and severity of medical condition were roughly equivalent.

Participants agreed to be randomized into one of three groups: Lavage involving washing out the knee joint; Lavage followed by debridement, involving removing damaged cartilage or bone; and placebo surgery involving making skin incisions only. For consistency of surgical technique, one surgeon with 10 years of experience performed all procedures. Both the patients and the study staff responsible for follow-up care and assessments were unaware of group assignments. The director of Baylor College’s Center for Medical Ethics and Health Policy oversaw the stringent consent process of the study and assured ethical standards were upheld throughout the study.

Pain relief and functional improvement of the joint were assessed at seven follow up visits over the course of two years. At the first and second year follow up visits, moderate pain improvements were similar across all groups, as was functional improvements in walking and climbing stairs.

Researchers concede limitations. Since the participants were predominantly men, the study sample might not accurately represent all candidates for arthroscopic treatment of knee osteoarthritis. Furthermore, 44 percent of the 324 people eligible for study inclusion chose not to participate. The patients who agreed to participate might have had higher hopes of a positive outcome and consequently have been more influenced by the placebo effect. Furthermore, patients with severe osteoarthritis were excluded, so it remains uncertain whether the surgery would have been useful for them.

The study’s strength lies in the fact that it was the first in arthroscopic surgery research to compare the actual procedure to a placebo surgery. Its findings, showing that the placebo surgery delivers equally therapeutic benefits as the actual surgery, were certainly surprising.

The results leave the public questioning whether the billions of dollars spent on more than 650,000 procedures annually might be put to better use. It may be best to consider alternative therapies and remedies if you have moderate osteoarthritis for the knee. While the study did not recommend any specific alternative treatments, some typical ones involve exercise, anti-inflammatory drugs, pain killers, or heat-therapy. Doctors should use extra precaution in recommending candidates who could benefit from surgery.

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The Center for Quality Care and Utilization Studies at the VA Houston Medical Center facilitated this research. Funds were obtained primarily from the VA itself, while the Department of Medicine at Baylor College served as co-funder.

Moseley, Bruce. "A Controlled Trial of Arthroscopic Surgery for Osteoarthritis of the Knee."New England Journal of Medicine 347.2 (2002): 81-88.