Ankylosing spondylitis (ankylosis of the spine and sacroiliac (SI) joints)

Ankylosing spondylitis (ankylosis of the spine and sacroiliac (SI) joints)

Ankylosing spondylitis is an inflammatory condition belonging to the spondyloarthritides group and is primarily associated with axial involvement. The disease mainly causes inflammation of the entheses (the points where ligaments and tendons attach to bone), but many other organ systems may also be affected.