Knee surgery is a poor choice for arthritis

A report appears today in the New England Journal of Medicine, one of the foremost medical journals, that has a surprising result:

"Arthroscopic surgery for osteoarthritis of the knee provides no additional benefit to optimized physical and medical therapy."

I write "surprising" because this will indeed be surprising to many surgeons, and to their patients who have undergone unnecessary knee surgery. This study is interesting - and important - because it is a negative result, something which is difficult to obtain scientifically. It is also a classic case of a medical treatment that was initiated based on intuition rather than science: orthopaedic surgeons have been telling patients for years that their arthritis could be alleviated by "debridement" of the inside of your knee.

The new study by Kirkley et al. shows that the control group, which received physical therapy and "medical therapy" - ibuprofen, in other words - did just as well as the surgical group. Both groups improved, although neither group improved much. The conclusion: don't get the surgery! There is a huge downside to surgery - not only does it require weeks or months of followup therapy, but there is also the possibility of infection, not to mention the cost.

A friend of mine recently had exactly this surgery - he has arthritis in both knees, and his doctor told him that arthroscopy would smooth out the rough spots, which were causing him pain. This sounded reasonable, so my friend agreed. After months of follow-up therapy, his knee was only slightly improved.

Arthroscopic knee surgery was developed to treat torn cartilege and ligaments, and it works beautifully for these acute injuries. I have personal experience of this - some years ago I tore my cartilege in my left knee, and I couldn't even straighten my leg for a while. I had arthroscopic surgery which removed the torn cartilege and fixed the acute problem - though it left me with much less cartilege. However, treating an acute injury is far different from treating arthritis, which is a chronic, degenerative condition that affects huge numbers of people as they age.

Unfortunately, orthopaedic surgeons are not likely to give up this lucrative procedure so easily. An editorial appears in the same issue of NEJM, written by Robert Marx, a surgeon. He argues - with no scientific evidence to back him up - that some patients have both arthritis and torn cartilege, and that in such cases "it can be difficult to determine which of the two is the major cause" of knee pain. I can hear him already explaining to his patients that he recommends surgery.

Brian Feagan, a co-author of the new study, was clearly disappointed that NEJM printed this editorial, which he said (in today's Washington Post) would result in continued overuse of arthroscopic surgery. The Post points out that a second study in the same issue of NEJM, involving nearly 1000 patients, found that many arthritis patients have small cartilege tears, but that their pain is caused by arthritis, not the tears. "I'm very disappointed by the editorial. I'm not sure who he [Marx] is advocating we should treat," said Feagan.

Arthroscopic knee surgery is performed on hundreds of thousands of patients in the U.S. alone each year, costing about $5000 per operation. This new study shows that many of these operations - perhaps most of them - are unnecessary. I hope that surgeons will pay attention, but Marx's editorial makes it clear that some of them won't. For their patients, only a healthy skepticism - and perhaps a 2nd or 3rd opinion - will save them the pain and expense of unnecessary surgery.