Arthritis is a general term to describe inflammation of the joints. However, there are different types of arthritis, including osteoarthritis (OA) and rheumatoid arthritis (RA). Although OA and RA both affect the joints and cause inflammation and joint pain, they are very different forms of arthritis.
Degenerative disease vs. autoimmune disease
Osteoarthritis is the most common forms of arthritis and a degenerative disease (disease in which deterioration of structure or function of tissue occurs). People with OA experience a breakdown in the cartilage that cushions the joints. The worn cartilage causes bones to rub against each other, resulting in pain.
OA may be the most common form of arthritis, but RA is the most crippling. Rheumatoid arthritis is also one of the most common forms of autoimmune arthritis. It is a chronic disease, causing pain, swelling, joint damage and limited motion and function in the affected joints. RA can affect any joint, but the small joints of the hands and feet seem to be most affected. Moreover, inflammation may affect organs, including the eyes, lungs, heart, and skin.