Psoriatic arthritis (PA) is a form of joint inflammation affecting individuals with the skin disorder psoriasis.
• Approximately 10-20% of those with psoriasis may develop some form of arthritis.
• When joints are inflamed they become tender, swollen and painful on movement.
• Joints are typically stiff after resting, early morning or resting in the evening.
• Tissues such as ligaments, tendons around the joints may be involved.
• Inflammation of tendon or muscle (such as tennis elbow (Lateral Epicondylitis) and pain around the heel) is also a feature in those with psoriatic arthropathy.
• In approximately 80% of cases the arthritis develops after the appearance of psoriasis.
• In 20% of cases the joint inflammation comes first.


Joints normally function to allow movement to occur between bone ends, which are important for the body to move. Bone ends are covered with cartilage around which is a capsule lined by a membrane called synovium.

This membrane normally makes the fluid that lubricates the joint space allowing movement. In arthritis the synovial membrane becomes inflamed - and releases substances that cause inflammation.

The inflamed synovium releases more fluid than normal and so the joint becomes tender and swollen. Persistent inflammation may lead to damage to the cartilage and erosion of the underlying bone.

Synovial membrane also lines and lubricates tendons and so they become inflamed too.


There are several features that distinguish PA from other forms of arthritis:
• Particular patterns of joints that may be involved.
• One pattern of inflammation is usually in the end joints of fingers often corresponding with the fingers that have psoriatic nail involvement, which is more common in men than women.
• Another pattern is involvement of the joints of the spine and sacroiliac joints which is called spondylitis similar to ankylosing spondylitis.
• Neck pain and stiffness.
• An entire toe or finger can become swollen or inflamed which is termed dactylitis.
• There is a tendency for joints to stiffen up and sometimes to fuse together.
• Importantly the absence of rheumatoid factor in the blood helps distinguish psoriatic arthritis from rheumatoid arthritis.
• Distinguishing features are not always present and the individual may have swelling of a few or many joints that is similar to other types of arthritis making diagnosis difficult.


• It may come on at any age.
• Uncommon in children, although cases have been diagnosed.
• Usual for the condition to develop in the teenage years.
• The arthritis can develop before the skin psoriasis is apparent.
• In woman there may be an increased incidence following pregnancy or the menopause.
• Men are a little less commonly affected than women. Men are more prone to developing arthritis of the spine Women are more prone to severe disease of other joints

• Early diagnosis is essential.
• Outlook is favourable with good management of the condition and regular monitoring by a rheumatologist.
• Only a small minority of individuals will go on to develop severe and widespread joint damage.
• Joints that are initially involved in PA are usually the ones that continue to cause the problems at a later stage.
• Markers to identify individuals with potentially more severe arthritis are now becoming practical and will help in reflecting the most suitable type of treatment.


There are many effective treatments - psoriatic arthritis treatments for psoriatic arthritis.

• Always rest severely inflamed joints.
• Exercise (under medical supervision) affected joints and muscles which have stiffened helps prevent loss of movement.
• Proper medical advice is vital about medications that can control inflammation and joint damage.
• Joint injections of some types of steroid can be very effective, although these do not work equally well in all individuals. They are safe when used in moderation and with precision.
• Diet: no particular diet has shown to be uniformly effective, cutting down on saturated fats helps some people and may reduce the doses needed of other treatments.
• Dietary supplements such as evening primrose oil and certain fish oils are of variable effect too but are safe and have other health benefits.
• Ultraviolet light helps psoriasis in some cases, otherwise climatic conditions such as the weather have a minor role to play, those whose skin and joints wax and wane together are hence better in summer than winter.
• Remember many so-called 'Cures' for arthritis are not proven by clinical trials to be of use and may be driven by profit to those advocating them.


In 80% of individuals with arthritis, psoriatic nail changes are found, which is more common than with psoriasis alone.

Nail changes include pitting, discolouration of the nail due to abnormalities in the growth of tissue in the nailbed.

The risk of developing arthritis is greater in individuals with severe psoriasis, yet occasionally severe arthritis may occur with minimal skin disease.

Topical medications for skin psoriasis such as Vitamin D derivatives have not been shown to benefit joints. Retinoid may have beneficial effect on the joints in some cases but side effects limit duration of use.


•The cause of psoriatic arthritis is the subject of much research.
• You cannot 'catch' arthritis or psoriasis from someone else. Therefore they are not CONTAGIOUS!
• Psoriasis can he provoked by sore throats, if due to streptococcal infections, and it is possible that germs may provoke joint Inflammation and flare-ups of psoriatic arthritis.
• Trauma and stress may be contributing factors, although not proven.
• Psoriatic arthritis is not strictly hereditary BUT there is a genetic contribution.
• The genetic make-up of an individual is likely to determine the risk of developing psoriasis and arthritis, and probably influence the severity.
• There are certain genetic markers linked to the immune system which are now being used to predict severity of arthritis. (Read more)
• Much more is known about the mechanisms that lead to inflammation in other conditions and it is likely advances in science will lead to much more effective treatments with fewer side effects.

Remember: All treatments may have unwanted side-effects or special precautions (e.g., during pregnancy). Always make sure you have all the information before embarking on any course of therapy, this includes reading the Patient Information Leaflets (PIL) provided with your medicines.

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