ABSTRACT
Osteoarthritis (OA) can be defined as a disorder of articular joints characterized by deterioration of articular cartilage; osteophyte formation and bone remodeling; pathology of periarticular tissues including synovium, subchondral bone, muscle, tendon, and ligament; and a low-grade, nonpurulent inflammation of variable degree. OA is differentiated from rheumatoid arthritis (RA), which is the classic example of a primary immune-mediated systemic condition characterized by bone destruction and articular cartilage erosion. RA is a more destructive, progressive, and debilitating condition than OA. Other forms of arthritis should be similarly differentiated from OA.
