Ankylosing spondylitis

What is ankylosing spondylitis?

Ankylosing spondylitis (AS) is an inflammatory condition affecting the joints of your spine. Your body reacts to this inflammation by depositing calcium where ligaments attach to the vertebrae of the spine. This causes a stiffening of the spine and may eventually lead to a fusion of some of the spinal bones.

AS usually affects the lower spine where it meets with your pelvis, although it can affect other parts of the spine and other areas of the body.

Who gets ankylosing spondylitis?

Ankylosing spondylitis can affect anyone, although it’s most common in young men and most likely to start in your late teens or 20s.

The genes you inherit from your parents may make you more likely to develop AS, but the condition isn’t passed on directly. Most people with ankylosing spondylitis have a gene called HLA-B27, which can be detected by a blood test. This gene isn’t the cause of ankylosing spondylitis but it does contribute to it.

Having this gene doesn’t mean you’ll definitely get AS, and the blood test isn’t very useful in diagnosing the condition. Even in families where somebody’s been diagnosed with ankylosing spondylitis, there may be brothers or sisters who have the HLA-B27 gene but who don’t have the condition.

Where can I find out more about ankylosing spondylitis?

Versus Arthritis

nassNational Ankylosing Spondylitis Society

  • About AS – including diagnosis information and living with AS
  • Exercise – information about the benefits of exercise in AS, and different exercises that AS sufferers can try at home, including an exercise video
  • Exeter Branch

Last updated: February 6, 2020