The latest clinical-practice guideline for treating osteoarthritis of the knee weighs in on the science behind treatments that are less invasive than knee replacement surgery. Developed by the American Academy of Orthopaedic Surgeons and published in the February 4, 2009 issue of the Journal of the American Medical Association, the guideline "is a reminder to the public and health-care providers of the importance of lifestyle changes," says Susan Joy, MD, director of Womens Sports Health at Cleveland Clinic. "Modern medicine makes it easy to try to avoid lifestyle changes. People think, If I get an injection of pain medicine into my knee, I dont have to exercise or If I get a knee replacement, I dont have to lose weight. But these treatments dont replace a lifetime management strategy for minimizing your disease risk or the risk of progression if you do have something wrong."