Ankylosing spondylitis is an inflammatory disease that can cause some of the vertebrae in the spine fuse together. This fusing makes the spine less flexible and can result in a hunched-forward posture. If ribs are affected, it may be difficult to breathe deeply. Ankylosing spondylitis affects men more often than women. Signs and symptoms of ankylosing spondylitis typically begin in early adulthood. Inflammation also can occur in other parts of the body, most commonly eyes.