Acetabular surgery is frequently utilized to manage developmental dysplasia of the hip and hip problems associated with cerebral palsy. During the operation, accurate correction of the orientation of the acetabular fragment is necessary. We describe a technique that enables accurate assessment of the coronal plane alteration in orientation. Intraoperative image intensifier records were compared with postoperative films and the accuracy of the coronal plane correction was evaluated. We found the intraoperative sourcil angle closely correlated to the postoperative angle to within 1°. The Spearman correlation coefficient was R=0.97, suggesting a close relationship between the two measurements.