Sacroiliitis in seronegative polyarthritis: CT analysis.

Sacroiliac joint abnormalities were evaluated by computed tomography (CT) in 29 patients with psoriatic arthritis and in 15 with colitic arthritis. CT showed a better sensitivity than conventional X-ray analysis in the evaluation of the articular space alterations in psoriatic and colitic arthritis as well as in detecting erosions and ankylosis of sacroiliac joints in patients with ankylosing spondylitis or psoriatic arthritis. Thus, CT appears a promising tool for the early detection of the pathological changes of sacroiliac joints.