Health conditions

Ankylosing spondylitis

What is ankylosing spondylitis?

Ankylosing spondylitis (AS) is a painful inflammatory rheumatic condition that is characterised by inflammation of structures in the spine. It is part of a group of disorders called spondyloarthritis.

What causes AS?

The cause of AS is not known, but the risk of getting it is greater if a relative is affected.

Who is at increased risk of AS?

AS only affects around 0.5 per cent of the population. It is more commonly found in men than women and usually starts in young adulthood. The presence of a gene called HLA B27 (human leukocyte antigen) is associated with a higher risk of AS.

What are the signs and symptoms?

The symptoms and signs of AS include:

  • pain and stiffness:
  • at the lower back, buttocks, mid-back or neck
  • typically worse at night or after prolonged rest
  • which improves with activity
  • joint pain and swelling, usually in the larger joints recurring tendon pain (a tendon is the soft tissue by which muscle attaches to the bone) decreased ability to do daily activities including work, home and recreational interests fatigue or tiredness.

Other organs can also be involved, with inflammation of the eyes, skin, lungs and gastrointestinal tract.

If left untreated:

  • the ongoing inflammation within the spine and other musculoskeletal soft tissues and joints can increase bone formation
  • joints may become stiffer, fuse together and lose function. This can prevent a person from being able to bend down or stretch.

If you suspect you have AS

Consult your general practitioner if you are concerned you might have AS. They may recommend a blood test for the gene, HLA B27 and refer you to a rheumatologist who will perform a thorough examination.

Can AS be prevented?

AS cannot be prevented. The earlier the diagnosis, the sooner a management plan can be started, to help you better manage pain and stay active.

Can AS be treated?

A management plan can help you manage AS, and may involve:

  • prescription of medications such as non-steroidal anti-inflammatory drugs (NSAIDs)
  • regular exercise to reduce pain and stiffness and strengthen muscles and joints
  • support from relevant health professionals, such as physiotherapists.

Where to get help


  • Ankylosing spondylitis cannot be prevented, but it can be managed.
  • The condition affects more men than women, and onset usually between 30 and 40 years.
  • See your GP if you have symptoms of AS.


painHEALTH: Musculoskeletal Pain Health


See also

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