What is ankylosing spondylitis? Ankylosing spondylitis is a chronic, long-term inflammation of the joints between the vertebrae and between the spine and pelvis. It is an autoimmune disorder, meaning affected individuals express a unique protein (HLA-B27) that mistakenly triggers the immune system to attack healthy joint tissues. Over time, the affected joints can become fused together. The disease is thought to have a genetic component. It generally develops between 20 and 40 years of age and is three times more common in males (Source: PubMed). Ankylosing spondylitis usually begins with pain and stiffness in the lower back and pelvis and worsens with inactivity, particularly during sleep or in the morning. The disease can improve with exercise. Over time it may spread to involve other sections of the spine and may begin to limit your mobility, particularly in the lower spine and sometimes in the rib cage. The course of ankylosing spondylitis is unpredictable. You may experience periods of remission and unless your hips are severely involved, you have a good chance of retaining fairly good spinal function. Unrelated infections and stress can provoke new attacks.There is no known prevention of the disorder, but in many cases medications and exercise can improve both pain and functionality. Surgery is used only in rare cases of severe pain. Ankylosing spondylitis is a life-long disorder and can restrict your mobility, but it is not life threatening on its own. In rare cases, it can contribute to aortic heart valve and heart rhythm problems, pulmonary fibrosis, or restrictive lung disease. A more common complication is fracture or injury due to the spinal damage. Seek immediate medical care (call 911) for serious symptoms of back injury, such as severe pain, numbness, weakness of the extremities, or urinary and fecal incontinence.