WHAT IS RHEUMATOID ARTHRITIS (RA)

Rheumatoid Arthritis (RA) is a common form of arthritis affecting approximately 1% of the population or 2.1 million people in the U.S.

RA is a chronic systemic inflammatory disease that involves primarily the synovial membranes (membrane surrounding a joint that creates a protective sac and cushioning for the joint) and articular structures of multiple joints. (see diagram below) The disease is often progressive and results in pain, stiffness, and swelling of joints. In late stages deformity and ankylosis can develop.

In rheumatoid arthritis a person’s immune system produces destructive molecules that cause inflammation of the synovium. Collagen contained in the cartilage is gradually destroyed, narrowing the joint space and eventually causing damage to the bone.

Anyone can get RA, including children, (Juvenile Rheumatoid Arthritis) , however this disease most commonly strikes people aged 25 – 50 years of age. Women are three times more likely than men to suffer the effects of RA.

How Does RA Differ From Other Forms of Arthritis

RA tends to effect joints in a symmetrical pattern, meaning, if one knee or hand is affected, generally, the other knee or hand will also be affected.

The pattern of joint involvement is important in helping distinguish RA from other forms of arthritis. Generally with RA the knuckle closest to the fingernail will not be affected, whereas in osteo arthritis this is the joint most likely to be effected.

Joints that maybe effected by RA include the hands, wrists, elbows, shoulders, neck, jaw, hips, knees, ankles and feet. Generally the spine, other than the neck, is not directly affected.

It is not uncommon to have osteo arthritis as well as Rheumatoid Arthritis.

Doctors look at the pattern of joint involvement along with findings from certain laboratory tests to Diagnose RA.

What Causes RA?

Rheumatoid arthritis is an autoimmune disease where a person’s immune system attacks his or her own body tissues.

Scientists have yet to discover why this happens but have found that RA develops as a result of the interaction of many factors. Listed below are the most common of these factors.

- Genetic predisposition


- Female sex


- Psychological stress


- Immune response


- Hormone interaction


- Viral infection

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This information is not designed as or intended to be used as medical diagnosis or advice. Patients should consult their physicians about diagnosis and treatment.