The term arthritis literally means inflammation of a joint, but is generally used to describe any condition in which there is damage to the cartilage. Inflammation is the body's natural response to injury. The warning signs that inflammation presents are redness, swelling, heat and pain.
The cartilage is a padding that absorbs stress. The proportion of cartilage damage and synovial inflammation varies with the type and stage of arthritis. Usually the pain early on is due to inflammation. In the later stages, when the cartilage is worn away, most of the pain comes from the mechanical friction of raw bones rubbing on each other.
There are over 100 different types of rheumatic diseases. The most common are:
Osteoarthritis is sometimes called degenerative arthritis because it is a “wearing out” condition involving the breakdown of cartilage in the joints. Joint cartilage is a gel-like protective tissue found at joint surfaces that provides support and lubrication during movement. When cartilage wears away, the bones rub against each other, causing pain and stiffness. OA usually occurs in people over age 50, and often in people with a family history of osteoarthritis.
Rheumatoid Arthritis (RA)
This disease produces chemical changes that cause the synovial membrane (the membrane that surrounds the joint) to become thickened and inflamed. In turn, too much synovial fluid (the fluid that lubricates the joints) is produced. The result of this chronic inflammation is cartilage loss, pain, and stiffness. RA affects women about three times more often than men, and may affect other organs of the body, including the skin and heart.
This condition may develop after an injury to the joint in which the bone and cartilage do not heal properly. The joint is no longer smooth, and these irregularities lead to more wear on the joint.
This is a bone disease that often affects the hip, in which bone formation is accelerated. The density and shape of the bone changes, which in turn causes bone pain and inflammation of the joints.
This disease can result when a bone is deprived of its normal blood supply, which may happen after organ transplantation or long-term cortisone treatment. Without proper nutrition from the blood, the bone’s structure weakens and may collapse and damage the cartilage.