Types

Ankylosing Spondylitis

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Ankylosing spondylitis, or “AS,” is a form of arthritis that causes pain and stiffness of the spine. The word "ankylosing" means rigid. In AS, the bones of the spine become very rigid and can fuse together. The symptoms usually begin in the lower back and may also affect the hips and the rest of the spine. Other joints are affected less frequently.

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