From Carol & Richard Eustice,
Your Guide to Arthritis.
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About.com Health's Disease and Condition content is reviewed by Kate Grossman, MD

Definition: Ankylosing Spondylitis is a type of arthritis which primarily affects the spine and sacroiliac joints. In advanced cases the spine can become stiff and rigid.

Pronunciation: an-kill-lo-sing spond-il-itis

Also Known As: AS, spondy

Common Misspellings: anklelosing, ankelosing, anklosing, spondilitis

Examples: The doctor diagnosed the patient with ankylosing spondylitis.