Popular Knee Surgery Works No Better Than a Placebo

Couldn’t resist writing this one up. The results of the following study have been making the rounds lately, in publications from the Wall Street Journal to the New York Times:

A popular surgical procedure worked no better than fake operations in helping people with one type of common knee problem, suggesting that thousands of people may be undergoing unnecessary surgery, a new study in The New England Journal of Medicine reports.

Specifically, researchers wanted to know about the effectiveness of arthroscopic surgery for patients with a torn meniscus, a crescent-shaped wad of cartilage in the knee. The operations are very common. About 700,000 are performed in the U.S. yearly, at a total cost of $4 billion.

But how much do they help?

A Finnish study set out to find the answer: 146 patients, from age 35 to 65, who had wear-induced tears of the meniscus and knee pain (but apparently not arthritis) took part. About half had mechanical issues such as locking or clicking in their joints.

The last-minute way that subjects were directed into one of the two groups was kind of cool:

Most patients received spinal anesthesia, remaining awake (one hospital used general anesthesia). Surgeons used arthroscopes to assess the knee. If it matched study criteria, nurses opened envelopes containing random assignments to actual or sham surgery. In real surgery, shaver tools trimmed torn meniscus; for fake surgery, bladeless shavers were rubbed against the outside of the kneecap to simulate that sensation. Nobody evaluating the patients later knew which procedure had been received.

Then, after a year ...

Each group reported a similar improvement. (That sound you just heard was billions of dollars flushing down the U.S. health care toilet.)

Of course the New York Times quotes surgeons defending the procedure for certain patients. And of course the surgeons have a point: for certain people, especially those who are young and in much pain from a major tear in the tissue, surgery is no doubt the best option -- maybe the only option.

But always remember: Surgeons are part of their own SIG (special interest group). They have been trained in, and have acquired expertise in, the act of performing surgery. They make their money doing so (not exclusively, true, but still, the honest, thoughtful ones realize the conflict this leads to).

It’s like when a member of the Avocado Growers Association says more Americans should be eating avocados -- for their health, of course.

So Frederick Azar, first vice president of the orthopedic surgeons academy, not surprisingly finds grounds to dismiss the study's results. He tells us he operates mostly on patients outside the study's purview, who have mild to moderate arthritis and meniscal tears that appear to be painful.

He might be wise to take a glance upstory at Dr. Kenneth Fine, an orthopedic surgeon also quoted. Of 100 people with knee pain, Fine says, a “very high percentage” will also have a tear in their meniscus. He goes on:

People love concreteness: ‘There’s a tear, you know. You have to take care of the tear.’ I tell them, ‘No. 1, I’m not so sure the meniscal tear is causing your pain, and No. 2, even if it is, I’m not sure the surgery’s going to take care of it.'

That’s the kind of wisdom we need more often.

Oh, did this news seem kind of, well, familiar to regular readers here?

If so, you may be remembering this post from May in which I reported another study showing that this kind of surgery was ineffective. For that study, the patients did have arthritis.

Now that we’ve covered the arthritis and non-arthritis sufferers, casting doubts about the usefulness of the procedure generally, maybe we can finally shave a billion or two off that annual $4 billion medical bill.