ANKYLOSING SPONDYLITIS IS a degenerative autoimmune disease. A form of inflammatory arthritis, it typically strikes young people in their prime—in my case, at twenty-eight, shortly after the first of my two sons was born. AS is roughly analogous to having rheumatoid arthritis in the spine. My immune system attacks my body, causing chronic inflammation that began in the sacroiliac joints at the base of the spine and for the past ten years has been gradually moving upward.
