Osteoarthritis: Explained With Pictures
From Carol Eustice, former About.com Guide
Updated November 20, 2011
About.com Health's Disease and Condition content is reviewed by the Medical Review Board
Osteoarthritis is the most common type of arthritis. On the other hand, rheumatoid arthritis
is recognized as the most crippling or disabling type of arthritis. Osteoarthritis (also referred to as degenerative joint disease or wear-and-tear arthritis) is caused by the breakdown of joint cartilage
. Cartilage acts as a cushion between the bones that form a joint. Cartilage loss can cause bone to rub on bone in a joint -- a condition that is very painful. Usually osteoarthritis begins in a single joint.
Rheumatoid arthritis is a chronic, inflammatory type of arthritis. It is also classified as an autoimmune disease (i.e., immune cells attack the body's own healthy tissues). The synovium (lining of the joint) is primarily affected by rheumatoid arthritis, but organs also can be affected. Multiple joints are usually involved with rheumatoid arthritis.