Ankylosing spondylitis is a type of arthritis that causes inflammation in the spine, leading to chronic pain and spine stiffening. Eventually it can lead to fusion of the spine. Ankylosing spondylitis often begins with pain in the lower back and buttocks and eventually travels up the spine. In some cases, ankylosing spondylitis is also associated with inflammation of the eye. The cause is unknown, but there is a strong link to the genetic marker HLA-B27.
There is no cure, but medication is effective and can help reduce the pain and decrease the risk of disability.