Arthritis is a broad term that covers a group of over 100 diseases. The word “arthritis” means “joint inflammation.” Inflammation is one of your body’s natural reactions to disease or injury. It includes swelling, pain, and stiffness. Inflammation that lasts a very long time or comes back, as in arthritis, can lead to tissue damage.
A joint is where two or more bones come together, such as the hip or knee.