From The American College of Rheumatology:
Osteoarthritis (also known as OA) is a common joint disease that most often affects middle-age to elderly people. It is commonly referred to as "wear and tear" of the joints, but we now know that OA is a disease of the entire joint, involving the cartilage, joint lining, ligaments, and bone. Although it is more common in older people, it is not really accurate to say that the joints are just “wearing out.” It is characterized by breakdown of the cartilage (the tissue that cushions the ends of the bones between joints), bony changes of the joints, deterioration of tendons and ligaments, and various degrees of inflammation of the joint lining (called the synovium).
This arthritis tends to occur in the hand joints, spine, hips, knees, and great toes. The lifetime risk of developing OA of the knee is about 46%, and the lifetime risk of developing OA of the hip is 25%, according to the Johnston County Osteoarthritis Project, a long-term study from the University of North Carolina and sponsored by the Centers for Disease Control and Prevention (often called the CDC) and the National Institutes of Health.
OA is a top cause of disability in older people. The goal of osteoarthritis treatment is to reduce pain and improve function. There is no cure for the disease, but some treatments attempt to slow disease progression.
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