• Arthroscopy is a common treatment in which surgeons remove part of a torn or damaged meniscus, a component of the knee's shock-absorption tissues. It does not directly address the lost cartilage, and the effectiveness of this option is controversial. According to a 2003 study in the Journal of Bone and Joint Surgery, fewer than half of patients with osteoarthritis reported less pain two years after the operation. Moreover, 15% needed a new knee within a year of surgery. And in a 2002 study of veterans, published in the New England Journal of Medicine, arthroscopy for osteoarthritis was no more effective than sham surgery. However, Feeley and co-authors suggest that it may help certain younger patients, such as those who have a meniscal tear but normal knee alignment.
• If only one part of the knee is arthritic, a knee brace can shift your weight so it rests on the healthy part, relieving pressure and pain. Braces relieved pain for 78% of patients in a 2006 study in the Journal of Arthroplasty.
• For people who find a brace helpful but don't want to wear one, a surgery called osteotomy works similarly. Surgeons realign the bone by removing a wedge of bone or adding a bone graft just below or above the knee. This shifts weight to the healthy part of the knee. Osteotomy is best for younger patients, because in those older than 65 there is a good chance all the cartilage is deteriorating, Feeley and co-authors write. Osteotomy can delay a knee replacement — sometimes for decades — but eventually you'll need a new joint. In multiple studies, researchers have found that 2% to 25% of people with osteotomy need a new knee within 10 years, and 10% to 34% require replacement within 15 years.
• The typical last resort is a knee replacement. Surgeons try to avoid this treatment in young people because the new joints only last for approximately 15 years, Feeley says, and "the more active you are, the more likely they will wear out," Switching out a mechanical joint is a more complex surgery than getting the first replacement, so doctors try to limit this treatment to older people unlikely to need multiple replacements. In addition, knee replacement limits activity in many of recipients, and surgeons advise switching to lower-impact exercises. Researchers found that, although 94% of patients participated in sports at some point before the surgery, only 34% did so afterward, according to a 2005 study in the Annals of Rheumatic Diseases.
• Cartilage restoration is appropriate for young people with early arthritis, when plenty of healthy tissue is still left. For small cartilage losses, surgeons use a technique called microfracture. They drill tiny holes in the bone, and the area naturally fills up with cartilage-like scar tissue. For larger gaps, surgeons can pull out a bit of healthy cartilage and send it off to a lab where it grows into a lot of healthy cartilage. Then they re-implant the new tissue. Not every orthopedic surgeon is experienced in these techniques, Feeley says, so you may need to search for a doctor who can provide these treatments.