Knee pain is a common ailment and increases in prevalence with age. Some people just tough it out. Others try glucosamine or natural remedies. Still others try over-the-counter medications or exercise. A few get a prescription for an exercise or weight-reduction program from their doctor. But unfortunately, there are many who get sent for a referral for a knee arthroscope.
And yet study after study shows that arthroscopy (a camera guided 'cleaning' of the knee) is no better than placebo. In the (in)famous study published in 2002 in the New England Journal of Medicine, it was shown that for patients with knee arthritis, actually doing arthroscopy on their knees in an operating room was just as effective as taking patients into the operating room, sedating them, nicking their knee and then doing absolutely nothing else. Further studies have reproduced this finding.
So while the number of arthroscopies for knee arthritis have decreased, perhaps it's been replaced in the surgical field with just knee replacement. In this procedure, the whole knee is replaced with a prosthesis. In 2009, knee replacements were the 13th most common procedure in the US - after such 'procedures' as cardiac angiographies, CAT scans and diagnostic ultrasounds. Over 676,000 knee replacements are done each year.
But again, there don't seem to be real good studies showing the benefit. Meanwhile, there are lots of harm and risk. Every surgery has a risk of bleeding and infection. Years down the line, any hardware inserted into the body can fail and break, necessitating repair. And the anesthesia associated with any surgery carries an independent risk of complications. For what benefit? We've found that 'washing' out a knee is of low utility. So where are the studies that show that 'replacing' it are better? Sure, we can always find anecdotal evidence that this or that person felt better after a knee repair. But have we shown this systematically? (To be fair, the whole ethics of a placebo-controlled surgical trial is murky.)
And though the wages of those producing and inserting the knee replacements may be high, what are the expenses to the patient and society?