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Arthritis in children is called Juvenile Idiopathic Arthritis, or JIA for short.

Juvenile means it happens before you are 16 years old
Idiopathic means we don't know what causes it
Arthritis means joint swelling

This page will tell you more about JIA. If you have other questions please ask us.

What is arthritis?

A sore, swollen knee joint of an arthritis suffererTo move our bodies smoothly, and in all sorts of directions, we need good joints that are well oiled, just like the moving parts of a bicycle.

Inside our joints is a special protective lining (the synovium) which produces an oil called synovial fluid. With the right amount of fluid we can get dressed, run, jump, play games, write and use a keyboard.

In JIA, the synovium is inflammed and becomes swollen, just like the swelling of the skin after an insect bite.

When the synovium is swollen it starts to jam up the joint and produce more fluid. This makes the joint look puffy and difficult to move. The irritation of the synovium can also cause pain.

I thought only old people got arthritis

It is true that older people are more likely to have problems with their joints than young people, but children can get problems with their joints too. These problems include JIA.

Because JIA is very unusual, it is unlikely you will know anyone else who has it. Even in a big school, you might be the only one.

If the right treatment is found, arthritis can be made to disappear for long periods of time so that you feel comfortable and can do everything that you want. This is called remission.

Why do I have juvenile idiopathic arthritis (JIA)?

A part of your body called the immune system usually protects you from bugs (bacteria and viruses like coughs and colds). In JIA this gets confused and attacks your joints by mistake. We agree this is an odd thing for the body to do.

We don’t really know why the body becomes confused in some children and not others. It is likely to be due to lots of reasons and mostly bad luck.

Is this the only reason why my joints are difficult to move?

When your joint swells, it also stops your muscles from working properly. These muscles can become less fit and strong so when you exercise they feel tired more quickly. This may add to the pain and stiffness after running around and in the evenings.

To help, we will give you exercises to strengthen these muscles

We want you to continue with PE and joining in with other sports you enjoy. This will not make your JIA worse and will help to keep you fit. If it is painful then you may need to rest. This is why you see our physiotherapists.

Will I always have JIA?

We don't know what will happen in the future.

  • The JIA may come and go on its own. Sometimes it disappears for a long time.
  • Some children’s JIA gets better as they get older and their medicine can be stopped.
  • Medicine may make the JIA much less of a problem. Sometimes when the medicine is stopped the arthritis comes back and more medicines are needed.
  • We have good treatments for children with JIA. We might not be able to fully control your JIA all of the time, but it shouldn't stop you from enjoying your life and achieving your best.

What happens if JIA isn't treated?

Without medicines, JIA will cause damage to the joint lining and the joint may become more painful and not work properly.

You may not know that damage is happening as it happens very slowly and the body may be trying to repair itself all the time.

Medicines help get to control JIA and stop damage from happening to protect your joints for the future.

Being healthy and active and doing your exercises also help to protect your joints.

What else may happen in JIA?

Some children with JIA (about one in four) also have inflammation in their eyes. This can be treated with eye drops. Unlike with your joints you can’t see of feel this happening. This is why you need your eyes checked regularly in clinic by a specialist.