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."