More than twenty years ago, in July 2002, in the authoritative medical journal The New England Journal of Medicine an article was published that caused shock in the global medical community. Orthopedic surgeon Bruce Moseley of Baylor College of Medicine and the Veterans Hospital in Houston proved something hard to believe: one of the most popular knee operations did not work. Moreover, it was no more effective than an ordinary placebo.
This experiment forever changed the approach to evidence-based medicine, forcing doctors to question the "gold standards" of treatment that had been taken on faith for decades.
Context: the epidemic of knee "cleaning"
In the 1990s and early 2000s, knee arthroscopy for osteoarthritis was one of the most frequently performed operations in the United States. About 650 000 such procedures were performed annually.
The essence of the procedure consisted of two actions:
- Lavage (washing): The joint cavity was washed with saline solution to flush out "inflammatory particles" and cartilage debris.
- Debridement (sanitation): The surgeon shaved off and removed damaged, "frayed" areas of cartilage and meniscus.
The logic was simple and seemed irrefutable: if a joint hurts and creaks, it means it is "dirty" or "damaged." It needs to be "cleaned" and "flushed," like a rusty mechanism. Patients often felt better after surgery, surgeons earned good money, and insurance companies readily paid for the procedure.
However, this logic had one fatal problem: no rigorous placebo-controlled studies had ever been conductedconfirming that it was the operation itself, and not the natural course of the disease or the placebo effect, that brought relief.
A daring experiment: sham surgery
Bruce Moseley, being a surgeon, decided to test the effectiveness of his own profession. He understood that the only way to learn the truth was to conduct a "blind" study with a placebo group. But how do you create a placebo in surgery?
Moseley developed a protocol unprecedented in its boldness and ethical complexity. 180 veterans with knee osteoarthritis were randomly divided into three groups:
- Debridement group: Patients underwent a full arthroscopy with removal of damaged tissue.
- Lavage group: Patients underwent arthroscopy, but the joint was only washed with saline solution.
- Placebo group (sham surgery): Patients were given anesthesia, three small incisions were made on the skin (so that scars would remain, as after a real operation), the equipment was turned on, the sounds of surgical intervention were created, and even conversations among the surgeons were simulated. However, the instruments were not inserted into the joint itself, and no manipulations were performed.
After the operation, stitches were placed on the incisions. Neither the patients nor the doctors assessing the results (walking, descending stairs, pain sensations) knew which procedure had been performed on whom.
The ethical storm
Before beginning the study, Moseley had to pass through the crucible of ethics committees. The idea of "operating" on people simply to make incisions on their skin seemed sacrilegious to many colleagues.
To observe ethics, Moseley personally spoke with each patient. He honestly warned: "You will be given anesthesia and incisions will be made on your skin. But with a probability of 33% we will not perform the operation itself inside the joint. You may receive a sham procedure". Despite this, patients agreed to participate, trusting the doctor.
Results that changed medicine
The results were assessed at 6, 12, and 24 months after the operation. Strict pain scales and objective mobility tests were used.
The results, published in 2002 year, were stunning:
- There was no difference between the groups. Patients whose knees were actually "cleaned" and patients who simply had incisions made on their skin (placebo) demonstrated the same improvement in pain reduction and increased mobility.
- Moreover, in some tests the placebo group showed slightly better results than the groups that underwent actual surgical intervention, although statistically this was not a significant deviation.
The placebo effect worked flawlessly. The brains of the patients, who believed they had undergone a complex and expensive operation, triggered powerful endogenous pain-relief mechanisms.
The aftermath: the end of the era of knee "cleaning"
Moseley's article became a time bomb for orthopedics.
- Changes to clinical guidelines. Within a few years, leading medical associations revised their protocols. Arthroscopy for osteoarthritis was removed from the lists of recommended procedures for osteoarthritis as the primary diagnosis. Knee arthroscopy remains justified for other conditions — for example, for mechanical symptoms, certain meniscal tears, or loose bodies.
- The economic effect. Insurance companies and government programs (for example, Medicare in the USA) stopped paying for this operation in cases of arthrosis. This saved the healthcare system billions of dollars.
- Saving thousands of patients. Millions of people were spared the risks associated with anesthesia, infections, thromboses, and nerve damage that inevitably accompany any operation, even a minimally invasive one.
The lesson of Bruce Moseley
Bruce Moseley did not deny the results of his study, although as a surgeon it would have been advantageous for him if the operation worked. He courageously admitted that his profession had been misleading patients for decades, relying on "expert opinion" and tradition rather than on rigorous evidence.
The story of 2002 remains one of the most striking lessons of evidence-based medicine. It proved that a doctor's intuition, logic, and even the personal experience of thousands of successful operations can be mistaken, if they are not confirmed by randomized controlled trials. And that the power of the human brain (the placebo effect) is sometimes capable of working wonders without requiring a surgeon's scalpel.
