There are more than 100 different types of arthritis and the major types that affect the knee are osteoarthritis, rheumatoid arthritis, and posttraumatic arthritis.
Symptoms. The main symptoms of rheumatoid arthritis are joint pain, swelling and stiffness. It may also cause more general symptoms, and inflammation in other .
Involvement in large joints such as the knee, including inflammation, swelling, & stiffness (especially in the morning) tends to occur in later stages of RA.