Predominant cervical involvement in patients with psoriatic arthritis: report of two cases.

Cervical spine involvement is common but usually delayed in patients with psoriatic arthritis. We report two cases with early and predominant involvement of the upper cervical spine. Synovitis of the atlanto-odontoid joint and fusion of multiple facet joints were noted in one patient. In the other patient, the main finding was atlanto-axial subluxation with erosions of the odontoid process and anterior arch of C1. No abnormalities were noted in the peripheral joints, sacroiliac joints, or thoracolumbar spine. Analgesics and conventional antiinflammatory agents were only minimally effective. TNFalpha antagonist therapy (infliximab followed by etanercept) in one patient and phenylbutazone therapy in the other improved the symptoms and led to shrinkage of the pannus.