Arthritis is a catchall term for more than 100 diseases that cause inflammation and pain in your joints. The most common forms of arthritis include:
Osteoarthritis
Of the 54 million people in the United States with arthritis, 31 million suffer from osteoarthritis, which is a degenerative form of the disease that causes the cartilage in your joints to break down. Since your cartilage is responsible for helping your bones to slide together smoothly, its loss leads to pain and inflammation within the joint.
Rheumatoid arthritis
This form of arthritis is an autoimmune disorder in which your body mistakenly attacks your joints, causing pain and inflammation.
Psoriatic arthritis
This is an inflammatory disease wherein your body’s immune system attacks the connective tissue within your joints.
There are many other forms of arthritis, but these three make up the lion’s share of all diagnoses.