Psoriatic Arthritis

Psoriatic arthritis (PsA) is an inflammatory form of arthritis integrally linked to the autoimmune disease psoriasis. Symptoms include: 

  • Joint pain and stiffness 
  • Swelling of the fingers and toes 
  • Skin lesions
  • Nail deformity
  • Back pain 

Psoriatic arthritis can develop in people who don’t have a history of psoriasis, but it’s preceded by psoriasis around 85% of the time.

The causes of PsA are poorly understood, but genetics and environmental factors are believed to be at the root of the condition. Treatment focuses primarily on alleviating inflammation with either oral or injected medications. Surgery is rarely needed.

Psoriatic arthritis affects up to 1% of the U.S. population, affecting men and women equally. It’s typically diagnosed between ages 30 and 50, but it can occur at any age.

Frequently Asked Questions

  • What are the first signs of psoriatic arthritis?

    Most of the time, psoriasis is the first symptom of psoriatic arthritis. It causes silvery-white skin lesions called plaques, which may appear on your scalp, elbows, knees, and lower back. Eventually, pain and stiffness develop as inflammation spreads from the skin to the joints and/or connective tissues.

  • What are the 5 types of psoriatic arthritis?

    Psoriatic arthritis is broadly divided into two groups- axial, which involves the spine and hips, and non-axial, which involves the peripheral joints.

    It can be further classified into 5 types:

    • Asymmetric oligoarticular: Affects two to three joints on one side
    • Symmetric polyarthritis: Affects more than four joints on both sides
    • Distal interphalangeal predominant (DIP): Involves the joint closest to the tips of fingers or toes
    • Psoriatic spondylitis: Involves inflammation and pain in the spinal column
    • Arthritis Mutilans: A severe form of erosive arthritis leading to bone loss and deformity
  • What foods trigger psoriatic arthritis?

    While no diet is shown to cure PsA, inflammatory foods may exacerbate symptoms. They include:

    • Red meat
    • Dairy
    • High-fructose corn syrup
    • Refined sugar
    • Refined carbs (white bread, white rice)
    • Trans fat

    An anti-inflammatory diet emphasizes whole grains, oily fish, dark green leafy vegetables, and fruits.

  • What does psoriatic arthritis look like?

    Psoriasis causes patches of red, rough skin with silvery scales. They’re most often around the joints of elbows, knees, hands, and feet. The skin surrounding the joint may develop blisters and appear cracked. On the scalp, it may look like dandruff.

Key Terms

How Psoriatic Arthritis Affects the Body

Explore interactive models that take a closer look at the effects of psoriatic arthritis throughout the body, and how the condition can progress both internally and externally.

Page Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Veale DJ, Ritchlin C, Fitzgerald O. Immunopathology of psoriasis and psoriatic arthritis. Ann Rheum Dis. 2005;64 Suppl 2:ii26-9. doi:10.1136/ard.2004.031740

  2. Merola JF, Espinoza LR, Fleischmann R. Distinguishing rheumatoid arthritis from psoriatic arthritis. RMD Open. 2018;4(2):e000656. doi:10.1136/rmdopen-2018-000656

  3. Liu JT, Yeh HM, Liu SY, Chen KT. Psoriatic arthritis: Epidemiology, diagnosis, and treatment. World J Orthop. 2014;5(4):537–543. doi:10.5312/wjo.v5.i4.537

  4. Cleveland Clinic Center for Continuing Education. Psoriatic Arthritis. Updated October 2016.