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Arthritis Health Center

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Ankylosing Spondylitis


Ankylosing spondylitis is a form of joint inflammation (arthritis) that is long-lasting (chronic) and most often affects the spine. Ankylosing spondylitis commonly causes pain and stiffness, with swelling and limited motion in the low back, middle back, neck, hips, chest wall, and heels. Over time, joints in the spine can fuse together and cause a fixed, bent-forward posture.

In early ankylosing spondylitis, there is inflammation of the joints and of the ligaments where they attach near the joints.

In advanced ankylosing spondylitis, there is:

  • Fusion of joints in the spine.
  • Flattening of the normal curve in the low back.
  • Often a flattening of the normal curve of the neck, an increase in the forward curve of the upper back, and bent posture at the hips.

Other joints can become painful and stiff, including those in the shoulders, wrists, hands, knees, ankles, and feet.

Although it is unusual, ankylosing spondylitis can also cause changes such as thickening of the major artery (aorta) and the valve in the heart called the aortic valve. Scarring of the lungs also happens in rare cases. The kidneys and the digestive tract can also be affected.

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerRicha Dhawan, MD - Rheumatology

Current as ofSeptember 9, 2014

WebMD Medical Reference from Healthwise

Last Updated: September 09, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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