In the United States, more than 650,000 knee surgeries called arthroscopic debridement or lavage are performed each year, at a cost of about $5,000 each. A report in the New England Journal of Medicine shows that knee surgery to remove cartilage is worse than doing nothing. The headline from Baylor Medical School, where the landmark study was performed, is "Study Finds Common Knee Surgery No Better Than Placebo." Patients with osteoarthritis of the knee who underwent placebo arthroscopic surgery were just as likely to report pain relief as those who received the real procedure. The researchers say their results challenge the usefulness of one of the most common surgical procedures performed for osteoarthritis of the knee. Lead investigator Dr. Elda P. Way states, "The fact that the effectiveness of arthroscopic lavage or debridement in patients with osteoarthritis of the knee is no greater than that of placebo surgery makes us question whether the one billion plus dollars spent on these procedures might not be put to better use."
In the study, 180 patients with knee pain were randomized into three groups. One group received debridement, in which worn, torn, or loose cartilage is cut away and removed with the aid of a pencil-thin viewing tube called an arthroscope. The second group underwent arthroscopic lavage, in which loose cartilage is flushed out. The third group underwent simulated arthroscopic surgery; small incisions were made, but no instruments were inserted and no cartilage removed. The people who did not have surgery on their cartilage did better than the people who had some of their cartilage removed.
The knee is just two sticks held together by four bands called ligaments. Bones are soft, so the ends of bones are covered with a hard gristle called cartilage. Cartilage serves as a padding to protect the ends of bones. Once cartilage is broken, it can never heal. And once you break a small amount of cartilage in your knee, your knee cartilage can never fit together properly, and every time you put force on the knee, you break off more cartilage.
When surgeons remove cartilage, they leave less cartilage than the person had before the surgery. Eventually the knee joint runs out of cartilage and when bone rubs on bone, it hurts all the time and a peson must have a knee replacement just to be able to sleep at night. Surgery to remove cartilage just hastens knee replacement. On the other hand, doctors can replace torn ligaments, which stabilizes the knee joint. They can remove a loose piece that is blocking the movement of the joint. People with loose cartilage have sudden locking of the knee when they walk or the cannot fully straighten or bend their knees.
Based on this study and my own impression from treating hundreds of damaged knees, I recommend that you do not get knee surgery unless you have a torn ligament that needs to be repaired or you have sudden locking of the knee during walking or you cannot fully straighten or bend you knee. Otherwise surgery is likely to hasten your need for another surgery, knee replacement. Journal reference for this article Knee replacement surgery