What is psoriatic arthritis?

Like other types of arthritis, psoriatic arthritis causes pain and stiffness in the joints. It is called ‘psoriatic arthritis’ because it tends to affect people with psoriasis, a condition that causes red, scaly patches on the skin.

Although the exact causes of psoriasis are not well understood, the condition is thought to involve the immune system behaving abnormally. If you have psoriatic arthritis, your immune system attacks the surface of the bones in your joints.

Types of psoriatic arthritis

There are different types of psoriatic arthritis, which tend to affect different parts of the body. These include:

• asymmetric arthritis – usually affects one side of the body, or different joints on each side
• symmetrical polyarthritis – often affects several joints on both sides of the body
• distal interphalangeal arthritis – affects the joints closest to the fingernails and toenails
• spondylitis – affects the spine, particularly the lower back
• arthritis mutilans – a rare condition that severely affects the bones in the hands.

There is also a type of psoriatic arthritis that affects children, although the symptoms are usually mild.

Symptoms of psoriatic arthritis

Psoriatic arthritis can affect people in different ways. In some people, it can come on slowly and cause mild symptoms, while in others it may come on quickly and be more severe.

If you have psoriatic arthritis, you might have symptoms such as:

• pain, swelling and stiffness in one or more of your joints, such as your knees
• pain and stiffness in parts of your spine, such as the lower back
• pain in your tendons, such as in your feet
• thick or coloured fingernails or toenails
• pain or redness of the eyes.

Many people find that their symptoms come and go. At times they may worsen (called a ‘flare up’) or go away for a while (called ‘remission’).

Treatment of psoriatic arthritis

Although there is currently no cure for psoriatic arthritis, there are treatments that can relieve symptoms and help prevent long-term damage.

While some people's symptoms are so mild that they don’t need treatment, most require ongoing treatment by a medical specialist called a rheumatologist. Depending on your symptoms, your doctor may also refer you to a skin specialist (dermatologist) or an eye specialist (ophthalmologist).

You may need to try several different treatments before your doctor can find out what works best for you. Treatment may also need to be changed over time.

The main treatments for psoriatic arthritis include:

• pain killers (for example, paracetamol) and anti-inflammatories (for example, ibuprofen) to help control pain and swelling
• other medications, such as steroids or disease-modifying anti-rheumatic drugs (DMARDs), during flare ups or in severe cases.

Other types of therapy may be helpful, such as physiotherapy and occupational therapy. You can also do things to help yourself, such as eat well, exercise regularly, and quit smoking if you currently smoke.

For more information, see Arthritis Australia’s booklet ‘Taking control of your Psoriatic Arthritis’.