The word "arthritis" refers to several diseases that occur inside
the joints between bones. The main symptom of all types of arthritis is pain in
the joints, especially with movement. This pain can limit movement, making life
difficult. It is important to know the difference between types of arthritis,
because they are treated differently and have different long-term
Rheumatoid arthritis causes swelling and inflammation of specific
tissues (synovium) found in the joints. The synovial tissues are responsible
for producing the synovial fluid needed for normal joint function. In
rheumatoid arthritis, the synovial tissues inside the joint are damaged when
they are attacked by the body's own
The immune system is made up of specialized cells that act as a
surveillance and defense system against foreign substances such as bacteria and
viruses. Normally the immune system has a series of checks and balances that
allow it to identify foreign substances and to keep them from attacking the
body's tissue. For unknown reasons, occasionally the immune system will begin
attacking the body's own tissues. Any disease in which the immune system
attacks the body is called an
autoimmune disease. When the tissue attacked is the
joints, the result is rheumatoid arthritis.
When cells of the immune system attack your joint tissues, you feel
pain, swelling, and stiffness in the joint. Over time as your body attempts to
repair the damage caused by the attack, your joints become distorted and
nonfunctional, and movement is increasingly difficult. The activation of the
immune system releases chemicals into the bloodstream that are used as
messengers to coordinate the activities of widely distributed cells, and these
chemicals can cause symptoms of tiredness and fever.
The cause of rheumatoid arthritis is unknown, and there is no known
way to prevent the disease.
Primary Medical Reviewer
Anne C. Poinier, MD - Internal Medicine
Specialist Medical Reviewer
Nancy Ann Shadick, MD, MPH - Internal Medicine, Rheumatology
How this information was developed to help you make better health decisions.