Due to the fact that this is an autoimmune disorder, the cause and mechanism by which it works is not very well understood. Like other autoimmune disorders, it is the body’s own defense system that is attacking itself. In the case of rheumatoid arthritis, the target of these attacks is the joint. More specifically, it is the thin linings between joints, called the synovium, which are slowly deteriorated and are eventually completely destroyed. 

Because the synovium acts as a layer of cushion between the two pieces of cartilage within a joint, its deterioration can lead to serious damage. In most cases, inflammation, stiffness, and pain begin to occur once the disease destroys the synovium and begins to wear down on the joint’s cartilage. Because the two pieces of cartilage are not meant to be within direct contact with one another, this is the time at which the common symptoms of rheumatoid arthritis begin to present themselves.

Because not all joints within the body have synovia, rheumatoid arthritis affects certain parts of the body more than others. The most commonly affected joints are the small joints of the hands, feet, and spine. Other larger joints, such as the knees and shoulders, are also often affected by this disorder. Because of the stiffness and pain that is caused in these vital areas, rheumatoid arthritis can lead to a substantial loss of movement and function.

Although rheumatoid arthritis is mainly known for the pain it inflicts on joints, it can have other serious affects throughout the body. The cartilage and ligaments within a joint, for example, rely on the synovium and synovial fluid to act as a buffer during joint movement and impact. Without this buffer there to ease tension, the cartilage and ligaments are strained to work harder and are often injured in the process. In addition, the inflammation caused by rheumatoid arthritis can have detrimental effects on other organs throughout the body.

Rheumatoid arthritis is a chronic disorder, which means that it is a lifelong condition. Although symptoms may not always be present, the disorder is still affecting the body. Many people experience flare-ups, at which time stiffness and pain are at their worst. Because it cannot be cured, people living with this disease cope best by trying to alleviate the inflammation and pain as much as possible during a flare-up.