Unusual cervical spine involvement in psoriatic arthritis: a case series.

Cervical spine involvement in psoriatic arthritis is not uncommon and can often mimic symptoms and signs of ankylosing spondylitis. However, some specific features may help to differentiate between patients with psoriatic arthritis and ankylosing spondylitis. Here, we present a series of three patients with psoriatic arthritis and increasing cervical pain and loss of mobility. Each of the cases shows specific radiographic characteristics. These cases therefore illustrate different aspects of the involvement of the cervical spine in axial forms of psoriatic arthritis and highlight the importance of proper evaluation and management of axial disease in psoriatic arthritis.