1. Take the Ankylosing Spondylitis Quiz
2. Myths and Facts About Back Pain

Medical Author:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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Medical Editor:

Catherine Burt Driver, MD

Catherine Burt Driver, MD

Catherine Burt Driver, MD, is board certified in internal medicine and rheumatology by the American Board of Internal Medicine. Dr. Driver is a member of the American College of Rheumatology. She currently is in active practice in the field of rheumatology in Mission Viejo, Calif., where she is a partner in Mission Internal Medical Group.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• Ankylosing spondylitis facts
• What is ankylosing spondylitis?
• What causes ankylosing spondylitis?
• What are ankylosing spondylitis symptoms and signs?
• How is ankylosing spondylitis diagnosed?
• What are ankylosing spondylitis treatment options?
• Can ankylosing spondylitis be prevented?
• What is the prognosis (outlook) for patients with ankylosing spondylitis?
• What is in the future for patients with ankylosing spondylitis?
• Where can people find more information about ankylosing spondylitis and learn about support groups?
• Take the Ankylosing Spondylitis Quiz
• Myths and Facts About Back Pain
• Ankylosing Spondylitis FAQs
• Patient Comments: Ankylosing Spondylitis - Symptoms
• Patient Comments: Ankylosing Spondylitis - Treatments
• Patient Comments: Ankylosing Spondylitis - Experience
• Find a local Rheumatologist in your town
• Ankylosing Spondylitis Index

The diagnosis of ankylosing spondylitis is based on evaluating the patient's symptoms, a physical examination, X-ray findings (radiographs), and blood tests. Stiffness, pain, and decreased range of motion of the spine are characteristic of the inflammatory back pain of ankylosing spondylitis. Symptoms include pain and morning stiffness of the spine and sacral areas with or without accompanying inflammation in other joints, tendons, and organs. Early symptoms of ankylosing spondylitis can be very deceptive, as stiffness and pain in the low back can be seen in many other conditions. It can be particularly subtle in women, who tend to (though not always) have more mild spine involvement. Years can pass before the diagnosis of ankylosing spondylitis is even considered.

The examination can demonstrate signs of inflammation and decreased range of motion of joints. This can be particularly apparent in the spine. Flexibility of the low back and/or neck can be decreased. There may be tenderness of the sacroiliac joints of the upper buttocks. The expansion of the chest with full breathing can be limited because of rigidity of the chest wall. Severely affected people can have a stooped posture. Inflammation of the eyes can be evaluated by the doctor with an ophthalmoscope.

Further clues to the diagnosis are suggested by X-ray abnormalities of the spine and the presence of the genetic marker HLA-B27 identified by a blood test. Other blood tests may provide evidence of inflammation in the body. For example, a blood test called the sedimentation rate is a nonspecific marker for inflammation throughout the body and is often elevated in inflammatory conditions such as ankylosing spondylitis. X-ray tests of the sacroiliac joints can demonstrate signs of inflammation and erosion of bone. X-rays of the spine can progressively demonstrate straightening, “squaring” of the vertebrae, and end-stage fusion of one vertebra to the next (ankylosis). Fusion up and down the spine can lead to a “bamboo spine” appearance on X-ray tests with complete loss of mobility.

Urinalysis is often done to look for accompanying abnormalities of the kidney as well as to exclude kidney conditions that may produce back pain that mimics ankylosing spondylitis. Patients are also simultaneously evaluated for symptoms and signs of other related spondyloarthropathies, such as psoriasis, venereal disease, dysentery (reactive arthritis or Reiter's disease), and inflammatory bowel disease (ulcerative colitis or Crohn's disease).