Psoriatic Arthritis: The Basics
Psoriatic arthritis is a form of inflammatory arthritis that can affect some of the millions of Americans who have psoriasis. Psoriasis is a skin disease that causes a red, scaly rash, most commonly over the elbows, knees, ankles, feet, hands, and other areas.
Are there different types of psoriatic arthritis?
There are five types of psoriatic arthritis. It is important to know which type of psoriatic arthritis you have and to understand the characteristics so that it may be treated properly.
Symmetric psoriatic arthritis: Symmetric arthritis affects the same joints -- usually in multiple matching pairs -- on opposite sides of the body. Symmetric psoriatic arthritis can be disabling, causing varying degrees of progressive, destructive disease and loss of function in 50% of people with this type of arthritis. Symmetric psoriatic arthritis resembles rheumatoid arthritis.
Asymmetric psoriatic arthritis: Asymmetric arthritis typically involves one to three joints in the body -- large or small -- such as the knee, hip, or one or several fingers. Asymmetric psoriatic arthritis does not affect matching pairs of joints on opposite sides of the body.
Distal interphalangeal predominant (DIP): Distal interphalangeal predominant psoriatic arthritis involves primarily the small joints in the fingers and toes closest to the nail. DIP psoriatic arthritis is sometimes confused with osteoarthritis, a chronic disease that causes the deterioration of joint cartilage and bone as well as bone spurs at the joints.
: Spondylitis affects the spinal column and may cause inflammation and stiffness in the neck, lower back, spinal vertebrae, or sacroiliac region (pelvic area), making motion difficult. Spondylitis also can attack connective tissue, such as ligaments, or cause arthritic disease in the joints of the arms, hips, legs, or feet.
Arthritis mutilans: Arthritis mutilans is a severe, deforming, and destructive form of psoriatic arthritis that primarily affects the small joints in the fingers and toes closest to the nail. This leads to lost function of the involved joints. It also is frequently associated with lower back and neck pain. Fortunately, this type of psoriatic arthritis is rare.