of Ankylosing Spondylitis (AS)

Spondyloarthritis is an immune-mediated chronic inflammation of the structures of the spine.  A normal immune system fights off infections and kills abnormal cells that can grow into cancers.  In people with spondyloarthritis, immune cells localized in different areas of the spine become activated and start damaging your own tissues.  These inflamed tissues produce chemical signals released into the blood stream that recruit additional immune cells.  The end result is chronic inflammation that can destroy tissues.  In the setting of spondyloarthritis, the end result of this inflammatory process is the calcification of spinal structures.  The spine can become fused.

Most commonly, four illnesses can cause spondyloarthritis.  Ankylosing spondylitis, psoriatic spondylitis, reactive arthritis, and arthritis associated with inflammatory bowel disease can cause characteristic changes in the spine.  Each illness has its own distinctive characteristics in regard to initiating the illness and it primary manifestations.  Therapies for these illnesses are similar but not identical because of the associated underlying illness causing the spinal disease.

Next: Symptoms & Signs of AS