['Sacroiliitis (SI) is one of the most frequent extraintestinal manifestations in inflammatory bowel disease (IBD) patients, but the exact prevalence has not been evaluated in Asia. There are few data on the association between SI and other clinical features of IBD. The prevalence of SI was evaluated using computed tomography (CT) and the phenotypic parameters associated with SI in Korean IBD patients were determined.', "Eighty-two patients with ulcerative colitis (UC) and 81 patients with Crohn's disease (CD) were evaluated clinically. The presence of SI was evaluated using bone window setting of abdomino-pelvic CT images by two radiologists.", 'The prevalence rates of SI were 12.2% and 21.0% in the UC and CD groups, respectively. There was no relationship between the localization or extent of intestinal inflammation and the presence of SI in the UC group. Multivariate analyses confirmed that perianal and upper-gastrointestinal (from the mouth through to the jejunum) diseases were associated with the occurrence of SI in the CD group (p=0.026 and p=0.047, respectively).'] Is sacroiliitis common in Crohn 's disease patients with perianal or upper gastrointestinal involvement?