What is Psoriatic Arthritis?

Psoriatic arthritis is an autoimmune disease whereby the joints are under attack, causing swelling, pain, warmth, redness and stiffness as well as fatigue. Psoriatic arthritis can appear in any joint or where ligaments and tendons connect to the bone. It can also cause neck and back pain and stiffness.

The primary locations where psoriatic arthritis can occur can be broken down into three categories.

Enthesitis

Refers to the inflammation of the entheses, the site where ligaments and tendons attach to the bone, causing discomfort, stiffness and swelling. Common areas for this to occur are the back and bottom of the heels, around the elbows and knees, ribs, spine and pelvis.

Dactylitis

Also referred to as “sausage digits” due to the inflammation that occurs in a whole finger or toe. Dactylitis typically involves a few digits and is the result of the entheses, tendons and small joints in the finger or toe becoming inflamed.

Spondylitis

This refers to the inflammation of the spine, including the joints that connect the spine to the pelvis (sacroiliac joints) or one or more vertebrae. This can typically cause lower back and neck pain and stiffness.

People with psoriatic arthritis can experience the following five patterns.

Oligoarthritic psoriatic arthritis

Typically affects one to four joints, small or large.

Polyarthritis

Affects more than four joints in the body, usually the same ones on the opposite sides of the body.

Distal psoriatic arthritis

Primarily affects the small joints closest to the nail in your fingers and toes (this is characteristic of psoriatic arthritis).

Spinal psoriatic arthritis

This type of psoriatic arthritis affects the joints located on the spine and sacroiliac joints, making motion very difficult.

Destructive psoriatic arthritis

Also known as Arthritis Mutilans, this is a very severe, painful, deforming type of psoriatic arthritis that can affect the shape of the joint and tissue and bone that surrounds it. This type of psoriatic arthritis is rare.