The psoriasis is associated with inflamed joints in about one-third of those affected. In fact, sometimes joint pains may be the only sign of the disorder, with completely clear skin. The joint disease associated with psoriasis is referred to as psoriatic arthritis. Patients may have inflammation of any joints (arthritis), although the joints of the hands, knees, and ankles tend to be most commonly affected. Psoriatic arthritis is an inflammatory, destructive form of arthritis and is treated with medications in order to stop the disease progression.

    The average age for onset of psoriatic arthritis is 30-40 years of age. Usually, the skin symptoms and signs precede the onset of the arthritis.

    The psoriasis may involve solely the nails in a limited number of patients. Usually, the nail signs accompany the skin and arthritis symptoms and signs. Nail psoriasis is typically very difficult to treat. Treatment options are somewhat limited and include potent topical steroids applied at the nail-base cuticle, injection of steroids at the nail-base cuticle, and oral or systemic medications as described below for the treatment of psoriasis.