Osteoarthritis
Osteoarthritis, a degenerative disease characterized by inflammation of the joints between bones, usually as a result of wear and tear over the years. Osteoarthritis is the most common of the various kinds of arthritis . It affects joints of the neck, back (joints of the spine), knees, hips, fingers, thumbs, and big toes. Osteoarthritis occurs most often after age 45, and, according to the Arthritis Foundation, affects an estimated 20.7 million Americans. In a healthy joint, cartilage (smooth, elastic tissue that cushions the joint and allows for ease of movement) protects the ends of the bones. In osteoarthritis, years of joint use may eventually cause the cartilage to deteriorate, changing its surface from smooth to rough. Occasionally, a direct injury to a joint can cause osteoarthritis. As the cartilage deteriorates, the ends of the bones begin to rub together, causing joint swelling. Eventually, bone may grow along the sides of the joint in the form of lumps, or spurs. These join