Osteoarthritis is the single most common joint disorder. Known also as degenerative arthritis or degenerative joint disease, osteoarthritis is caused by the gradual wear and tear on a joint, leading to the loss of cartilage. As we age, the repetitive use of the joints causes joint pain, swelling and inflammation. Obesity also plays a role in putting extra weight and stress on joints. Patients with severe osteoarthritis have lost the cartilage between the bones, resulting in inflammation, constant pain and limited range of motion. Chronic inflammation can stimulate the bones to grow outgrowths, or spurs, around the joints, causing additional pain.