[Evaluation of the scanner and radiography in rheumatic pelvispondylitis]

We studied 20 normal subjects and 20 suffering from sacro-iliitis. The performance of the two techniques were compared in studying reports ROC curve from several readers. We assessed the performance of each technique and each sign: CT scan appears as a better technique than plain films. Some signs present a poor interest: osteophytes seen on CT or plain films, subchondral cysts seen on CT. In other respects, articular cartilage erosions, subchondral sclerosis are main signs as much on CT as on plain films. In conclusion, CT scan allowed an accurate analysis of sacro-iliitis. It has a better diagnostic value than plain films and, in case of doubt, should be performed to increase diagnosis sensibility and specificity.