Thanks to earlier diagnosis and more effective treatments, joint deformities in people with rheumatoid arthritis (RA) are becoming less frequent and severe.
What Causes Joint Deformities in RA?
In a joint affected by RA, inflammatory cells of the immune system gather in the lining of the joint (called synovium), forming a fibrous layer of abnormal tissue (called pannus). The pannus releases substances that quicken bone erosion, cartilage destruction and damage to the surrounding ligaments. The involved joints lose their shape and alignment, resulting in deformities. Severe deformities lead to loss of joint function and the need for joint replacement surgery.