What is psoriatic arthritis?

Psoriasis is a skin condition which usually causes scaly red patches of skin on the knees and elbows. Some types of psoriasis affect only the scalp causing red or flaky patches, often behind the ears or nails with ridges and tiny pits as well as flaking and splitting of the nails. Psoriatic arthritis is a type of inflammatory arthritis which can develop either in people who have skin or nail psoriasis or who have a close relative with psoriasis.

What are the symptoms of psoriatic arthritis?

Most people with psoriatic arthritis will have either skin or scalp psoriasis but others do not have any skin problems but may have a close family member with psoriasis. Psoriatic arthritis can affect adults of any age and causes pain, stiffness and swelling in the joints. Sometimes the pain and stiffness can be very mild and affect only one or 2 small finger joints but sometimes the problems can be more serious and affect many joints including the spine and sacroiliac joints.

There are several different patterns of joints which are affected although many people’s symptoms do not fit into an exact type.

  • Arthritis affecting the end finger joints (distal interphalangeal joints). This is usually associated with psoriasis of the finger nails.
  • Arthritis affecting a few joints, usually not symmetrically such as the knees, ankles, wrists or hips.
  • Arthritis which looks identical to rheumatoid arthritis, especially affecting the small joints of the hands and feet.
  • Arthritis affecting the spine and sacroiliac joints (ankylosing spondylitis)
  • Severely deforming arthritis (arthritis mulilans) which is rare and usually affects many joints.

If it is not treated, psoriatic arthritis can cause joint damage and lead to disability although some people will always have very mild joint problems.

How is psoriatic arthritis diagnosed?

Your rheumatologist will ask about the history of your joint problems as well as about your other medical conditions, what tablets you are taking and about your family history. They will examine your joints in turn looking for tenderness and swelling, and may examine other parts of the body depending on what is found. Psoriatic arthritis is usually a clinical diagnosis. This means that if you have obviously swollen painful joints, as well as psoriasis or a close relative with psoriasis, it is possible that you have psoriatic arthritis. There is no blood test which can diagnose psoriatic arthritis but doctors will usually check for other types of arthritis such as rheumatoid arthritis or gout with blood tests and sometimes x-rays of your hands, feet or other affected joints.
Sometimes, swelling of the joints is difficult to detect by examining the joints so if there is any doubt about whether or not your joints are swollen rather than just tender, you may have other tests such as an ultrasound scan of the hands, a magnetic resonance scan (MRI), or a special imaging test called an isotope bone scan.

Treatments for psoriatic arthritis

There are many different types of treatment for psoriatic arthritis and these can be divided into several groups.

  • Medical – including pain-killers, non-steroidal anti-inflammatory medicines (NSAIDs), joint injections and disease-modifying drugs (DMARDs) such as methotrexate
  • Physical therapies– including physiotherapy, osteopathy, chiropractic, massage and acupuncture
  • Surgical – including joint replacement and arthroscopy
  • Occupational therapy – including splints and devices to help daily living
  • Self-management – including pain management, exercise and exercises, weight management, dietary modification, relaxation and emotional support, stretching and improving sleep

The treatment of psoriatic arthritis depends on how many joints are affected and how severely. If only one or two small joints are affected, the treatments may be painkillers or anti-inflammatory tablets such as naproxen. Joint injections can also be helpful if one or two joints are involved but if many joints are affected, disease-modifying drugs similar to those used for rheumatoid arthritis such as methotrexate and sulfasalazine are often used. Biologic drugs such as anti-TNF drugs including etanercept or adalimumab are also used if the arthritis is severe. These drugs can also help with skin psoriasis.

As your arthritis improves, drug treatments may be reduced. Flares affecting one or two joints are sometimes treated with joint injections.

What can I do to help myself?

There are lots of ways that you can help yourself deal with the pain of diagnosis including trying to be more active and eating a healthy diet.

Read more about self-management