The immune system is designed to protect our bodies from infection and disease. But sometimes this system turns against the body it's supposed to protect. Doctors believe that this type of malfunction, directed against the joints, is the root cause of psoriatic arthritis.
This ongoing swelling and pain in the joints occurs in about 30% of people with the skin disease psoriasis, according to the <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=psoriasis" target="_blank">National Psoriasis Foundation</a>. Psoriasis itself is also believed to involve the immune system. 
Symptoms 
The course of psoriatic arthritis varies from one person to the next, but most people with the disease can still lead productive lives, according to the <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=arthritis" target="_blank">Arthritis Foundation</a>. 
The most common symptoms include pain and swelling in the wrists, knees, ankles or joints at the ends of the fingers or toes. The joints of the spine can also become swollen. 
The fingers and toes may become painful and swollen, referred to as a "sausage digit." People may feel stiff and tired in the mornings and find that they can't move the affected limb as much as they used to. Psoriatic arthritis can also cause redness and pain of the eye. 
Some people may have pain in the lower back or buttocks, silver or gray patches of scaly, itchy skin on the scalp, elbows, knees or lower end of the backbone, and small dents in the fingernails or toenails. 
The symptoms may appear slowly or quickly. Eighty-five percent of people with psoriatic arthritis had psoriasis before developing joint symptoms, according to the National Psoriasis Foundation. However, in some cases, arthritis symptoms develop first. 
Psoriatic arthritis is usually diagnosed between the ages of 30 and 55. It may be mistaken for other problems, such as an old sports injury or a different form of arthritis. 
How it's found 
No one test will show if a person has psoriatic arthritis. 
If a doctor suspects the disease, he or she may: 
<ul>
 <li>Ask about symptoms. </li>
 <li>Check for tenderness, pain or swelling in the joints and limitations in movement. </li>
 <li>Look for evidence of psoriasis on the skin, fingernails and toenails. </li>
 <li>Order x-rays to look for changes in bones and joints. </li>
 <li>Request blood tests to rule out other diseases. </li>
 <li>Test joint fluids to rule out gout or joint infections. </li>
</ul>
How it's treated 
Treatment options for psoriatic arthritis include skin care, light therapy, exercise and rest. In rare cases surgery may also be considered. 
Medicines used to treat psoriatic arthritis include pain relievers, anti-inflammatories, drugs that block the immune system and others that slow or stop damage to the joints and tissues. 
These treatments can help reduce pain and swelling, control lesions on the skin, and slow or prevent joint damage. Early treatment helps limit damage to joints and tissue. 
Helping yourself 
People with any kind of arthritis can make their own lives easier by seeking early treatment and following their doctor's advice. 
The <a href="[BASEDOMAIN]/healthinfo/bouncelink.aspx?shortcut=aota" target="_blank">American Occupational Therapy Association</a>&nbsp;offers these tips for around the house: 
<ul>
 <li>Wrap the handles of tools, pots and silverware with foam, cloth or tape. </li>
 <li>Replace round doorknobs and faucet handles with lever handles. </li>
 <li>Avoid lifting heavy objects. </li>
 <li>Pace yourself throughout the day and take breaks when you need them.</li>
</ul>
Reviewed 6/20/2023

What is psoriatic arthritis? 

Treatment can usually slow this disease and control the symptoms.