Ankylosing spondylitis is a disease that primarily affects the spine, although it can affect other parts of the body. It is a form of chronic inflammatory arthritis often characterized by back pain and stiffness. These symptoms typically appear in adolescence or early adulthood. They do vary significantly from one person to another, and not everyone will experience serious symptoms of ankylosing spondylitis. While the exact cause of ankylosing spondylitis is not known, scientists have identified a certain gene variation that may increase a person's risk for the disease, as well as other risk factors for the condition. Examples of treatment options for people with ankylosing spondylitis include lifestyle changes, medications, and surgery. Recent research has led to a new understanding of ankylosing spondylitis and has increased the likelihood that, in time, researchers will find even better ways to treat the disease.