Knee surgery is no more effective: Study

The new evidence should give doctors pause before they try to repair the meniscus, according to the Finnish doctors behind the research published in the New England Journal of Medicine, Newsmax Health reports.

The experiment involved 146 volunteers whose knee pain appeared to be caused by wear and tear of that cushion. None of the participants had a recognized injury or osteoarthritis, both situations for which the surgery is already known to be ineffective.

After 12 months, the average improvement among the people who received real surgery and those who got "sham" surgery was essentially the same, said the research team, led by Teppo Jarvinen, M.D., of the University of Helsinki.

 Because about 700,000 such surgeries are done in the U.S. each year at a cost of $4 billion, the new findings "will not be welcomed with open arms," Dr. Jarvinen predicted in a phone interview.

The study was done at five medical centers in Finland. All the volunteers had experienced knee pain for at least three months and doctors believed the problem was a tear of the medial meniscus. Nonsurgical treatment had not helped them.

Patients did now know whether they had real surgery because of the way the researchers set up the experiment. Once a doctor had used arthroscopic techniques to examine the knee, if surgery seemed appropriate, the medical team opened an envelope, with the equipment still in place, to reveal whether the patient would receive fake surgery or real surgery.

For sham surgery, the microshaver that is typically used by the surgeon for meniscus removal didn't have a blade.

The patient was not told which option was randomly chosen and neither the orthopedic surgeon nor other operating room staff were involved in further care of the patient. The patients were unable to guess whether they had received real surgery or fake surgery.

On two scales objectively measuring symptoms, there was little difference in outcomes between sham and real surgery.

But patients regarded the treatment as a success whether they received real surgery or not. Surveys showed 89 percent in the actual surgery group and 83 percent in the sham group reported improvement.

Five patients in the sham-surgery group and two who actually had surgery had such persistent problems that further surgery was required, but that difference wasn't large enough to demonstrate that the operation worked better.

But Craig Bennett, M.D., chief of sports medicine at the University of Maryland Medical Center, cautioned that the findings should not be over-generalized. 

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