👉 Arthritis is a chronic autoimmune disorder that causes inflammation and pain in the joints. It can affect people of all ages, but it most commonly affects people with rheumatoid arthritis (RA), psoriatic arthritis (PsA), or osteoarthritis (OA). The exact cause of arthritis remains unknown, but genetic factors, environmental factors, and lifestyle changes have been implicated. The term "arthritical" comes from the Greek word "arthros", which means inflammation. Arthritis is characterized