Your Diagnosis

Getting a diagnosis of axial spondyloarthritis (axial SpA) including ankylosing spondylitis (AS)

This information is for anyone with axial spondyloarthritis (axial SpA) including people with ankylosing spondylitis (AS)

Could I have inflammatory back pain?

You may have inflammatory back pain if you answer yes to at least 4 of the 5 of the statements below.

Back pain of more than 3 months duration is inflammatory if:

  • Your symptoms started before you were 40 years old
  • Your pain started slowly
  • Your pain and stiffness improve when you move around
  • Your pain and stiffness do not improve with rest
  • You have pain at night which improves if you get up and move around

What is inflammatory back pain?

Back pain is very common but in most cases the pain is ‘mechanical’. This means the pain is related to the way the muscles, ligaments, discs and bones work together.  Inflammatory back pain affects a much smaller number of people.

Inflammation is the body’s reaction to injury or irritation, and can cause redness, swelling and pain.

It is important to be able to distinguish inflammatory pain from mechanical pain, as the treatment is different.

The symptoms of inflammatory back pain

  • Starts before the age of 40
  • Has been present for at least 3 months
  • Has come on slowly over time
  • Is worse in the mornings
  • Causes stiffness in the mornings lasting for at least 30 minutes (stiffness is perhaps best described as the sort of aching you get the day after heavy exercise)
  • Improves with activity, and is worse with rest
  • Improves with anti-inflammatory drugs (e.g. ibuprofen)
  • Can wake people from sleep, often in the second half of the night
  • Can often cause pain in the buttocks, but rarely pain shooting down the leg (sciatica)


Inflammatory back pain is the main symptom of a group of conditions called spondyloarthritis.

Four main conditions make up the spondyloarthritis family.

  1. Axial spondyloarthritis  (axial SpA) including ankylosing spondylitis (AS)
  2. Enteropathic arthritis which is strongly linked with inflammatory bowel disease. It often affects the feet, ankles and knees
  3. Psoriatic arthritis may cause inflammation in the hands, feet, larger joints or the spine. The majority do have skin psoriasis, but some develop arthritis before they notice any psoriasis on their skin
  4. Reactive arthritis which is also known as Reiter’s syndrome. It develops as a reaction to an earlier infection, including bowel infections  and sexually transmitted infections. Most people’s symptoms will get better within 3 to 12 months

Getting your axial SpA diagnosis

Your first step is to go to your GP

You should be ready to explain:

  • What symptoms you are experiencing
  • How long these have been going on (weeks, months, years)
  • How the symptoms started (suddenly or came on slowly over time)
  • What impact your symptoms are having on your daily life and what are they stopping you from doing (be sure to highlight any issues around sleeping and work)

If another member of your family has axial SpA please make sure that you highlight this to your GP. If you have ever suffered with any of the following problems please also highlight this.

If your GP suspects axial SpA you should be referred to a rheumatologist at a hospital

They will confirm the diagnosis, decide the initial treatment and manage your condition in the long term.

Tests which might be used to confirm your axial SpA diagnosis include:

  • Physical examination by a nurse, physiotherapist or rheumatologist to assess your flexibility and joint tenderness
  • Blood test to look at inflammatory markers. If you have inflammation in a part of your body then extra protein can be  released from the site of inflammation and circulates in the bloodstream. The erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and plasma viscosity (PV) blood tests are commonly used. Do remember that in around half of all cases, inflammatory markers will be within the normal range. If your inflammatory markers are normal it doesn’t necessarily mean you don’t have inflammatory arthritis
  • A blood test which can identify if you carry the HLA-B27 gene. The HLA B27 gene is present in over 90% of people with axial SpA. Just carrying the HLA-B27 gene does not necessarily mean you have axial SpA or that you will go on to develop it but it’s a clue that your symptoms might point towards axial SpA.  Do remember 10% of people with axial SpA are HLA-B27 negative.
  • X-rays will show if there has been any changes to your bones and joints such as extra bone growth or fusion. Many people will never have changes on x-ray
  • Magnetic resonance imaging (MRI) which will show if there is any inflammation around your joints. A particular MRI sequence needs to be used to diagnose axial SpA. It is called a STIR sequence (Short TI Inversion Recovery).


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