Psoriatic arthritis

An inflammatory disease of the joints and skin

On the following pages, you will find information on chronic inflammatory joint diseases, which can also occur in combination with psoriasis. What exactly is behind these diseases? Which age groups are affected? How often do these diseases occur and what is a suitable psoriasis treatment that can positively influence their course?  Please read on.


What is psoriatic arthritis?

The cause of psoriasis and painful joints

Our immune system has the task of fighting pathogens in the body. However, if it malfunctions, it can also attack its own body; the technical term for this is autoimmune disease. Even though the cause of psoriatic arthritis has not yet been fully discovered, the symptoms are well known: the skin and joints become inflamed. The result: psoriasis and rheumatism.

Areas of the body that can be affected by psoriasis

Both the skin and the nails can be affected by psoriasis. Sometimes, the inflammatory skin disease also appears on the eyes. As a rule, arthritis starts later – on average, there are 10 years between the appearance of the first skin symptoms and the joint inflammations. Knee joints are most commonly affected, followed by fingers, ankles, and toes. The spine and tendon attachments can also suffer from the inflammatory reactions.

How often does psoriatic arthritis occur?

The exact number of people affected cannot be quantified, however, it is assumed that about 2 to 3% of the population in Europe1 suffers from psoriasis. In every second patient with skin psoriasis, the nails are also affected at the same time2. 20 to 30 percent suffer from arthritis at the same time3. The disease can occur equally in men and women at any age, but more frequently between the ages of 30 and 50.

How long will I live with psoriatic arthritis?

The disease accompanies sufferers throughout their lives and can vary in severity over time, as it occurs in episodes and is more noticeable during the winter months. 

Mild cases do not involve major changes in terms of work or social life. In severe cases, life expectancy is reduced by three to four years compared to people without psoriatic arthritis4.

Unable to work due to psoriatic arthritis?

If large joints or the spine are affected, psoriatic arthritis is also associated with a degree of disability (in Germany: Grad der Behinderung, GdB), up to severe disability (GdB >50). Whether this results in an inability to work depends very much on your job.


Before psoriatic arthritis can be treated, it needs to be diagnosed correctly.

Different ways to diagnose psoriatic arthritis

At the onset of the disease, psoriatic arthritis is often difficult to diagnose. In many cases, only individual joints are inflamed, which does not make it easy for the general practitioner to make a clear diagnosis as typically, finger and toe joints are affected. There are symptom-free phases between the individual episodes of the disease, which also make it difficult to diagnose.

Rheumatism values & X-ray examination provide a clearer picture

After palpation of affected joints, your blood should be examined in the laboratory. Elevation of relevant blood values will confirm the rheumatologist's suspicion. An X-ray examination, joint ultrasound or MRI provide information about the exact condition of the joints.

If the ultimate diagnosis is arthritis, the aim is to reduce inflammation in the joints, bones, and ligaments in order to relieve pain. The goal is also to maintain the original stability and function of the joints and prevent permanent changes.

Which examination for what purpose?

Laboratory examination of the blood

If relevant blood values are elevated, this is a clear indicator

X-ray examination

Provides information about the bone structure and shape of the same


Shows soft tissue structure, such as swelling or thickening of the synovial membrane

The symptoms of psoriatic arthritis

How does rheumatism manifest itself?

Between the individual episodes of the disease, there are phases without symptoms, which also make it difficult to make a diagnosis. In this case, the only thing to do is wait and closely observe the further course of the disease. Joint pain can have many causes: if the thumb, index and middle finger are affected, carpal tunnel syndrome may be present. If the knee joint is painfully swollen, this does not necessarily have to be rheumatic in nature. Patients with a Baker's cyst often complain of swelling on the inside of the back of the knee, restricted mobility and pain all over the knee joint. Causes can be meniscus damage, ligament instability or cartilage wear – and yes, rheumatic joint inflammation is also possible.

It often takes some time before the diagnosis of psoriatic arthritis is confirmed. A rheumatologist is the right specialist to see for the professional assessment of the inflamed joints. In contrast, the correct diagnosis of psoriasis is much easier, because psoriasis is associated with typical skin changes and features that are obvious to the dermatologist. A family history of psoriasis can be of importance.


The skin and nail changes of psoriatic arthritis are described in the chapter on psoriasis vulgaris, together with treatment options.

Psoriasis vulgaris
  • Acute infections: flu or cold
  • Chronic inflammation in the body
  • Stress
  • Climate factors such as dry, heated air
  • Low light during the winter months

Treatment of psoriatic arthritis

What helps against psoriatic arthritis?

Although it is not possible to cure psoriatic arthritis, there are a number of therapies that can delay progression of the disease. The aim is to reduce inflammation in the joints, bones, and ligaments and to relieve pain. There are three treatment options available: medication, physiotherapy and surgery.

To begin with, your doctor will prescribe a fast-acting medicine for the inflammation and joint pain – a so-called NSAID or non-steroidal anti-inflammatory drug in an adjusted dose.  

Effective medicines against inflammation

In the acute phase of the disease, additional anti-inflammatory medicines are often indispensable, as they contain the inflammation very quickly and effectively. If individual joints are severely affected, injections directly into the joint space can also help. The next stage of drug treatment is long-term rheumatism therapy with a basic therapeutic agent.

The main approach of the basic therapeutics is to regulate the misdirected immune system and thus stop or at least slow down psoriatic arthritis. Some patience is needed here as response to the medication takes a few weeks.

These include, for example, conventional synthetic disease-modifying antirheumatic drugs (csDMARDs). Since psoriasis can also involve the joints and spine, patients have been treated for rheumatism with conventional medicines almost unintentionally when their skin psoriasis was being treated. A clear improvement or even disappearance of their joint and spinal complaints was observed.

What helps beyond basic rheumatism therapy?

Biological disease-modifying antirheumatic drugs (bDMARDs), also called biologics, are used when treatment with basic therapeutics does not work sufficiently. Biologics are medicines that are directed against the body's own messenger substances, which play an important role in the development and maintenance of rheumatic diseases and psoriasis.

Targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs), so-called ‘small molecules’, can also be used for therapy. These medicines act inside the cells and interrupt signalling pathways that promote inflammatory reactions in the body. If drug therapy does not show satisfactory improvement in the joints, surgical measures and joint replacement are options. To maintain mobility, rheumatism physiotherapy in the context of occupational therapy or physiotherapy is important.

Non-drug measures, such as the exchange of experience in self-help groups or participation in patient training courses, are also of increasing therapeutic importance.


1 Ocampo VD, Gladman D. Psoriatic arthritis. F1000Res. 2019;8:F1000 Faculty Rev-1665. 2 Köhm M, Behrens F. Psoriatic arthritis. Current therapeutic standards. Z Rheumatol. 2017;76:495-503 4 Gossec L et al. EULAR recommendations for the management of psoriatic arthritis with pharmacological therapies: 2019 update. Ann Rheum Dis. 2020;79:700-712.