Ankylosing Spondylitis is an inflammatory disease that, over time, can cause some of the small bones in your spine (vertebrae) to fuse. This fusing makes the spine less flexible and can result in a hunched-forward posture. Ankylosing spondylitis is also a systemic disease, meaning it can affect tissues throughout the body, not just the spine. Other joints away from the spine manifest as arthritis, as well as to other organs, such as the eyes, heart, lungs, and kidneys. If ribs are affected, it can be difficult to breathe deeply.