Unlike osteoarthritis, inflammatory arthritis isn’t caused by wear-and-tear of the cartilage in your body’s joints. Instead, it occurs due to autoimmune disorders, in which the body’s immune system attacks its healthy cells, resulting in damaged tissue.
These damaged tissues, Arthritis-Health.com says, are what cause the “deformity, instability, and scarring within the joints” that are characteristic of inflammatory arthritis, among other symptoms. And while there are many different types of inflammatory arthritis, the following seven are the most common.
1. Rheumatoid Arthritis
Rheumatoid arthritis is by far the most common type of inflammatory arthritis, affecting approximately 1 to 2 million people in the United States alone. In those with rheumatoid arthritis, the Mayo Clinic says the immune system “attacks the lining of the joint capsule,” called the synovial membrane.
As the synovial membrane is attacked, the source says it “becomes inflamed and swollen,” which causes the pain and discomfort associated with the condition. Over time, the cartilage and bone within the joint can become permanently damaged. This most commonly occurs within the hands, wrists and feet.