The synovial joint is made up of bone, cartilage, a joint capsule, ligaments and the synovial membrane. The synovial membrane secretes a fluid called synovial fluid that nourishes the joint and reduces friction between the bones at the joint. Rheumatoid arthritis is a disease in which the synovial membranes are inflamed. It is a painful condition that affects small joints in places like the finger, wrists and feet. It is also a life long disease that is associated with various factors.
Causes
According to the Arthritis Foundation, the causes of rheumatoid arthritis are currently unknown. However, there are explanations as to what the causes may be. Rheumatoid arthritis is referred to as an autoimmune disease. In autoimmune diseases, the immune system, which normally attacks and destroys disease causing foreign bodies, goes awry and attacks parts of the body instead. In rheumatoid arthritis, this autoimmune reaction could lead to inflammation in any part of the body, but the synovial membrane is typically affected. "The Cleveland Clinic Guide to Arthritis," by John Clough also suggests that infections may cause rheumatoid arthritis.
Risk Factors
According to 2010 information from the Arthritis Foundation, 1.3 million Americans suffer from rheumatoid arthritis. Also, the Merck Manuals Online Medical Library reported in 2008 that one percent of the world's population suffers from this disease, as well. Though rheumatoid arthritis may afflict anyone, of all the people who have this disease, 70 percent are women. Also, even though men have a more severe form of rheumatoid arthritis, the risk of a woman developing this condition is three to four times that of a man.
The genetic marker referred to as HLA-DR4 is found in 70 percent of Caucasian men and women who have rheumatoid arthritis. Therefore, people who have this genetic marker may have an increased risk of developing the disease. However, having the genetic marker does not mean that the disease will definitely occur.
Progression
Rheumatoid arthritis occurs in stages, and as the stages progress, the effects of the disease become more and more severe. In the first stage, the synovial membrane becomes swollen and this causes pain, redness, warmth, swelling and stiffness at the affected joint. The next stage of the disease involves thickening of the synovial membrane. After this, destruction of bone and cartilage at the joint occur and this may lead to deformities, more pain and loss of movement in the joint.
References
- Merck Manuals Online Medical Library: Rheumatoid Arthritis (RA)
- Arthritis Foundation: Reumatoid Arthritis
- "Johns Hopkins White Papers, 2007, Arthritis" John A. Flynn, M.D., Timothy Johnson; 2007
- "The Cleveland Clinic Guide to Arthritis"; John Clough; 2009
- "Structure and Function of the Musculoskeletal System"; James Watkins; 2009
