Stay That Knife, Surgeon

Anyone else see this?

Over a third of the total knee replacements in the U.S. are inappropriate, according to researchers who found that many patients had pain and other symptoms that were too mild to justify having the surgery.

Actually, uh, it’s worse.

Along with the 34 percent of subjects for whom a total knee replacement was deemed inappropriate, there were 22 percent for whom the evidence was “inconclusive.” That leaves only 44 percent of the 175 subjects whose replacement surgery was definitely judged to be “appropriate.”

In other words, less than half.

Why that matters becomes clear when you see the statistics. More than 600,000 knee replacements are performed each year. That’s a big number, considering how extensive this operation is. What’s more, the number of the surgeries is on the rise.

In the past 15 years, the number of total knee replacements (TKR) has grown significantly, with studies showing an annual increase of nearly 100% in surgeries between 1991 and 2010. The number of Medicare-covered TKR surgeries grew by 162% annually over the same period.

It should go without saying that a total knee replacement should be considered a last resort. With biomechanical structures, even if they don’t work well, they’re still part of a dynamic, changing system that perhaps can heal. Once a surgeon starts sawing out a chunk of your femur to install a plastic-and-metal knee, that biological system is gone. The car-knee analogy then does become relevant. Your new knees will slowly start to wear out, just as a new car driven off the lot does. Plus, possible complications from surgery and the effectiveness of surgery are always two big unknowns.

Which all adds up to: There should be plenty of concern about unnecessary total knee replacements. In an editorial, Dr. Jeffery Katz, a professor at the Orthopedic and Arthritis Center for Outcomes Research at Brigham and Women’s Hospital in Boston, expresses concern that “doctors were offering TKR surgeries to patients who had mild pain and little loss of function in their knees.” He further writes:

As a community of providers, we implore our patients and the public at large to engage in exercise and physical activity in order to delay functional decline and to preserve and augment functional status. We must consider whether it is advisable and affordable to use costly technology such as TKR in the same fashion.