In the course of the next five years, most of us will experience regional pain in our knees lasting weeks to months. Without anything special happening, we'll notice aching in a knee when we put weight on it.
Walking will be unpleasant; walking quickly will be very unpleasant; and jogging may be out of the question. We might even limp. Climbing stairs will become difficult, but not as difficult as descending stairs … and there is prompt relief when sitting or lying down.
The knee might seem tight, even swollen, but not warm or so painful we can't bend it at all. Sometimes it feels as if it might give way. If it wasn't for this damnable knee pain, we'd be as well as ever. What to do?
Some will carry on as best they can until their perseverance is rewarded by a reversal of symptoms. Some seek relief in the over-the-counter remedies about which marketing has made us all keenly aware. Others will turn to doctors and other providers of care -- some who are licensed, some who are not. Each specialist will approach knee pain advocating treatments based on their own beliefs as to the reason the knee hurts.
After all this, we usually get better, and when we do, we naturally conclude that whatever treatment we received worked. It matters little that, in the case of knee pain, nearly all treatment approaches have been studied systematically and have no specific beneficial effect. We will return time and again to the same remedies when faced with the next episode of knee pain or backache.
Diagnosing Knee Pain
Each year more than 5 million people seek the care of American orthopedic surgeons for knee pain. All these patients are subjected to an examination of the knee that involves various yankings and pullings handed down from generation to generation of orthopedists despite the modern science that renders nearly all the "findings" nonspecific -- meaning the knee pain appears not to have a visible cause.
Nearly all these patients undergo an X-ray examination despite the fact that nearly all findings -- including osteoarthritis and spurs -- are common findings in ordinary knees that are not hurting. It's likely the conditions were present in the knee before it started to hurt and will remain there when it stops.
Nearly all undergo MRIs, which may show damage to ligaments and other structures in the knee (ACL tears, torn menisci, etc.). You get the idea: These findings, too, are nonspecific -- likely to be found in the knees of many who are walking or jogging today.
Treating Knee Pain
In our culture, the top of the therapeutic pyramid is occupied by the most technically based, usually invasive, potentially dangerous, expensive treatments. Some patients head straight for the top; others limp up only when their knee pain persists despite alternatives. Near the top are the doctors who are willing to inject something into your painful knee. They carry the most marginal scientific support of effectiveness. At the summit, decorated and highly rewarded, are the surgeons who are trained to fix the knee.
Science or no science, it is difficult for a surgeon and more difficult for a patient to see a damaged structure in the knee without linking the knee pain to that structure and fearing for the future. Furthermore, if the damage is reparable, shouldn't it be fixed?
Such reasoning induced a generation of orthopedic surgeons to offer their services in removing torn menisci by cutting open the knee. It took quite a while for patients to recover from the procedure, but most did. Most also have damaged knees when followed up decades later. Was the damage a result of whatever led to the tearing of the menisci in the first place or the surgery? We don't know. We do know that removing torn menisci by opening the knee is no solution in the long run.
Then along came arthroscopic surgery. Surgeons can now remove torn menisci, smooth damaged cartilage and repair other ligaments through tubes inserted into the knee using three tiny incisions. Recovery is rapid. The technology is impressive, though less impressive than modern digital cameras. The dexterity required also is impressive, though less so than the skill required to play most modern video games.
More than 500,000 knees are subjected to invasion by arthroscopes each year. It is the commonest elective orthopedic procedure in America. Most patients are grateful and bear the stigmata, the three little scars, as a sign of triumph. Arthroscopy is certainly responsible for a great transfer of wealth as this is an expensive procedure, but any certainty as to the specific benefit is being called into question by two recent randomized controlled studies of the procedure.
In the first of these trials -- from Texas in 2002 -- patients who had knee pain attributed to cartilage damaged by osteoarthritis received either an arthroscopic repair or a sham procedure, in which incisions were made but no surgery was actually performed. The patients, who were made aware of the possibility that some participants might get a sham procedure, did not know whether they got the real thing. In the end, there was no significant difference in the patients' outcomes when comparing the two groups.
In a second trial performed in Canada, patients received either the arthroscopic repair or "conservative" care, including physical therapy. In the course of two years, the surgery did not offer any advantage over the less invasive approach, the study's authors reported last month.
A Canadian-style trial would not come up with the same result in the United States. Most patients in the United States have the preconception that the surgery must be better because the knee feels better after surgery. Now we know such surgery offers the patient's knee no specific advantage.
The American orthopedic community is quick to explain that it reserves its arthroscopic surgery for patients with different causes of knee pain, such as meniscal or ACL tears, and that it is particularly adept at choosing the patients with osteoarthritis likely to be helped. My response is, "SHOW ME" with randomized, well-executed, sham-controlled trials.
Until the community does, I will advise my patients with regional knee pain to do the best they can, try an exercise bicycle or water aerobics and be patient. This too shall pass.
Dr. Nortin Hadler is professor of medicine and microbiology/immunology at the University of North Carolina at Chapel Hill, and an attending rheumatologist at University of North Carolina Hospitals. He is the author of "Worried Sick: A Prescription for Health in an Overtreated America" and "The Last Well Person."