Systemic means that RA, unlike osteoarthritis, affects the heart, lungs, and eyes of some patients in addition to the musculoskeletal system. Symmetrical is the key in distinguishing it from other kinds of arthritis. RA is one of the most common forms of arthritis. It affects mainly women in their forties, but it can also occur in children and in seniors over sixty-five years of age. It is an equal opportunity condition, affecting rich and poor alike.
Arthritis occurs more than half of the time in the fingers, wrists, shoulders, knees, and ankles.
Besides pain in the joints, it also causes trouble in other parts of the body, although involvement of the upper spine or lower sacroiliac joints is unusual.