Once the smooth contour of the cartilage is lost, the underlying bones harden and form spurs . The irregular surfaces of these rub against each other. Basically, the body is trying to defend itself against the process of wear and tear on the joints by building up more bone in the weak area. Pain is experienced when the new bone formations rub against each other and when they compress nerves. Rheumatoid arthritis not only affects the joints, but can also have a great impact on other parts of the body like the heart, blood vessels, eyes and muscles.
Inflammation plays a major role in rheumatoid arthritis.
With rheumatoid arthritis, the immune system, which normally defends the body, turns against certain body parts. The joints are most commonly targeted. With inflammation, there is a brief vasoconstriction of the blood vessels in the injured or arthritic area. Vasodilation then occurs, followed by a release of enzymes that cause cell necrosis. Histamine is released from these injured cells.