AS affects everyone differently, with some people having back pain and stiffness that comes and goes, while others suffer more severe pain that leads to varying degrees of spinal stiffness as the disease progresses. For almost everyone, AS will cause a cycle of very painful periods of time (flares) followed by periods when the symptoms disappear (remission). Other symptoms include pain and swelling in the neck, hips, knees, or ankles; difficulty expanding the chest; and fatigue. Other parts of the body can also be affected.

Ankylosing spondylitis can get worse over time, which is why getting help from a doctor as soon as possible is important. As AS gets worse, the spine gradually becomes stiffer and the bones in the spine may ultimately become fused or attached. This can severely limit a person’s mobility.