What Is Ankylosing Spondylitis (AS)

Ankylosing spondylitis (AS) is an inflammatory disease that causes pain in the spine, pelvis, and joints throughout the body. It is a chronic (lifelong) disease, and it is hereditary. AS causes abnormal bone growth, and causes joints to fuse (grow together) in the spine and in the sacroiliac joints (located between each hip and the…