Rheumatoid arthritis is a chronic inflammatory disease that predominantly affects the joints, especially small joints of the hands and feet. It is more common in women and involves symmetrical polyarticular inflammation of joints. The pathophysiology involves both cellular and humoral immune mechanisms leading to synovial membrane proliferation and cartilage/bone erosion. Osteoarthritis is the most common type of arthritis and is characterized by degeneration of joint cartilage and underlying bone, commonly affecting weight bearing joints like the hips and knees. Risk factors include age, obesity, trauma and genetics. Symptoms include joint pain, stiffness and decreased range of motion.