ABSTRACT
Osteoarthritis (OA), also known as degenerative joint disease or osteoarthrosis, is the most common type of arthritis. OA is a functional disorder of the joint, characterized by a change in joint shape secondary to a loss of articular cartilage, osteophyte formation, subchondral sclerosis, bone marrow lesions, and synovial proliferation, with consequent alteration of mechanical properties that result in decreased stability, movement, and loading [1, 2]. It is estimated to affect more than 27 million people in the United States and is the leading cause of physical disability and impaired quality of life in the industrialized countries. OA is strongly related to but not caused by aging, with most affected persons being older than 50 years. The higher life expectancy, the aging population, and the increase in number of overweight persons in the United States have led to an increase in prevalence of OA [3]. The resulting disability, comorbid disease, and expense of treatment are associated
Introduction ......................................................................................................................................23 Risk Factors for OA .........................................................................................................................24
