Ankylosing Spondylitis (AS) is a chronic inflammatory disease that affects primarily the sacroiliac joints (where the bottom area of the spine attaches to the pelvis), spine, and hip joints. Ankylosing is a term meaning stiff or rigid and Spondylitis means inflammation of the spine.  It is a form of autoimmune inflammatory arthritis that typically appears slowly and gradually. Symptoms of Ankylosing Spondylitis are listed as follows:

Joint swelling and pain in the knees, ankles and shoulders
Neck Pain, elbow and heel pain
Chronic fatigue or general weakness
Loss of appetite or weight loss
Eye inflammation (less common)
Limited range of motion and lower back stiffness
Stiffness and pain in the hips
Limited expansion of the chest
Limited Range of motion, most specifically in the hips and spine
Lower-back pain that is commonly worse at night, in the morning, or after periods of inactivity