There are five types of PsA, depending on which joints it affects. Distal interphalangeal PsA, for instance, affects the fingers and finger joints. Spondylitis, on the other hand, causes symptoms in the lower back.

Psoriatic arthritis (PsA) is a type of inflammatory arthritis that affects about 30% of people with psoriasis. It causes stiffness, pain, and swelling in the joints and where tendons and ligaments connect to bones.

People may also experience nail changes and psoriasis skin symptoms, such as plaques and scales. Nail changes result from inflammation where tendons and ligaments connect to bone and nails.

Doctors classify PsA into five types based on the number and location of joints affected. A person may develop one type at first and another type later in life.

Distal interphalangeal PsA affects the joints in the fingers.

Symptoms may include:

  • pain and swelling in the finger joints
  • nail changes, such as pitting, flaking, or separation from the nail bed
  • bony lesions

About 20% of people with PsA experience it in the distal interphalangeal joints only. Other people with the condition also experience pain or stiffness in other joints throughout the body.

Asymmetric oligoarticular PsA affects fewer than five joints. It gets the name “asymmetric” because it affects joints on one side of the body only. For example, a person may experience pain in their right elbow but not their left elbow.

Symptoms may include:

  • pain and swelling in the joints on one side of the body
  • involvement of fewer than five joints
  • involvement of small and large joints, such as those of the fingers and knee

Asymmetric PsA accounts for up to 60% of all PsA initial presentations, according to 2023 research.

Yet as PsA develops, it may progress, and this form of the condition may affect around 14% of people with psoriatic arthritis. Early symptoms commonly affect the knee.

Plus, according to a 2018 study, although experts typically agree that oligoarticular PsA affects five or fewer joints, some doctors may have difficulty diagnosing it and may conclude that a person has polyarthritis instead.

Polyarthritis affects five or more joints in the body and accounts for about 40% of all cases of PsA. The term “symmetric” means that polyarthritis affects joints on both sides of the body.

Symptoms may include:

  • joint pain and swelling
  • involvement of joints on both sides of the body
  • involvement of five or more joints

It typically affects small joints in the hands and feet.

A 2021 study found that 39% of people who receive a diagnosis of oligoarticular PsA go on to develop symmetric polyarthritis.

This type of PsA has symptoms similar to rheumatoid arthritis.

Spondylitis refers to inflammation and degenerative changes in the joints of the spine and sacroiliac joints located in the pelvis and lower spine.

People with other types of arthritis, such as enteropathic arthritis, may also have spondylitis. When spondylitis occurs in people with PsA, it’s known as psoriatic spondylitis. About 20% of people with PsA experience spondylitis.

Symptoms may include:

  • pain and swelling in the lumbar (lower) spine
  • pain and swelling in the spine, neck, or pelvis
  • fusion of vertebrae
  • pain and stiffness after prolonged immobility, such as after sleep

This severe condition affects about 2–21% of people living with PsA. Arthritis mutilans damages the joints of the hands, feet, fingers, and wrists. Symptoms include:

  • joint pain and swelling
  • finger shortening
  • fusion of joints
  • joint erosion
  • pencil-in-cup joint changes

Arthritis mutilans can significantly impair a person’s ability to use affected joints and reduce their functional independence.

Although PsA has no cure, treatment can help improve a person’s quality of life and prevent the condition from worsening over time.

Doctors may first recommend medications to address symptoms such as swelling and pain. Options include:

  • nonsteroidal anti-inflammatory drugs, such as ibuprofen or naproxen
  • steroids or injections into the joints, which people typically use for the short-term treatment of acute symptoms

Systemic treatments reduce the underlying inflammation that causes PsA symptoms.

Disease-modifying antirheumatic drugs (DMARDs) are one type of systemic treatment. They reduce overall inflammation and may help prevent further damage to the joints. DMARDs include:

  • methotrexate (Otrexup (PF), Xatmep, Trexall)
  • sulfasalazine (Azulfidine)
  • leflunomide (Arava)
  • apremilast (Otezla)
  • tofacitinib (Xeljanz XR)

Biological therapies are a newer type of treatment that target specific molecules in the immune system to reduce the inflammation responsible for PsA. They typically cause fewer side effects than traditional DMARDs. Options include:

  • anti-TNF medications, such as:
    • adalimumab (Humira)
    • certolizumab pegol (Cimzia)
    • etanercept (Enbrel)
    • golimumab (Simponi)
    • infliximab (Remicade)
  • interleukin inhibitors, such as:
    • ustekinumab (Stelara)
    • secukinumab (Cosentyx)
    • ixekizumab (Taltz)

Some people with severe PsA may require surgery to fix or fully replace damaged or deformed joints.

Doctors also often recommend physical therapy and regular exercise to increase strength, flexibility, and mobility in the joints and muscles.

How a person experiences PsA affects their recommended course of treatment. To create a treatment plan, a doctor may assess which type of PsA a person has, as well as their outcomes (or core domains).

These may include:

  • musculoskeletal disease activity, inflammation in the joints, and where tendons or ligaments insert into the bone
  • skin and nail disease activity
  • systemic inflammation
  • fatigue and pain
  • overall physical functioning
  • participation in daily life, for example, in family roles, social and leisure activities, and employment
  • emotional well-being, such as stress, self-worth, depressive mood, and anxiety

Research from 2019 indicates that early treatment for PsA can improve outlook. Because nearly one-third of people with psoriasis also develop PsA, it is important that people with psoriasis talk with their doctor right away if they think they’re experiencing arthritis symptoms.

Home remedies include lifestyle modifications that help address PsA symptoms and improve outlook. Examples of lifestyle changes include:

  • managing stress
  • practicing meditation and other forms of relaxation
  • regularly exercising
  • avoiding smoking, if you smoke
  • avoiding drinking too much alcohol, if you drink
  • eating a balanced diet that’s low in sugar, fat, and salt
  • applying hot and cold therapies to the joints
  • protecting the skin, avoiding skin irritants, and managing psoriasis, if present

Where does psoriatic arthritis usually start?

Where PsA starts can depend on the type of PsA a person has. It can affect small joints, such as those of the hands and feet, big joints like the knee, or vertebrae on the lumbar spine.

What can be mistaken for psoriatic arthritis?

Symmetric polyarthritis and rheumatoid arthritis both can have similar symptoms and may affect multiple joints on both sides of the body.

What is the most destructive form of psoriatic arthritis?

Arthritis mutilans is the most severe form of PsA and can result in the loss of the ability to use affected joints.

There are five classic types of PsA. Each type describes the number of joints and the location of joints that are affected.

Treatment varies according to the type of PsA a person has and how it affects them. It’s important for people to notify their doctor or another healthcare professional if they notice changes in their symptoms over time, as they may require a new treatment plan.