[The role of CT in diagnosis and therapy of fractures of the pelvic girdle].

The conventional pelvic overview and special projections of the pelvic ring are often not conclusive for the diagnosis of pelvic ring fractures. The superimposition of multiple bony and soft tissue structures interfere with correct three-dimensional orientation of the bony lesions in spite of special projections. CT offers the possibility of identifying pelvic fractures that are not visible in conventional radiographs. Dislocated fractures can especially be appreciated. With CT, it was possible for the first time to classify lesions of the sacroiliac joint: (I) distortion (vacuum phenomena), (II) rupture of the ventral sacroiliac ligaments (open book), (III) lesions of the ventral and dorsal sacroiliac ligaments, and (IV) luxation of the os sacrum. Lesions of the sacrum can also be classified into four groups: (I) diastasis of the sacroiliac joint, (II) sacral lip fractures, (III) vertical fractures and compression fractures, (IV) comminuted fractures. Above all, the CT scan facilitates an accurate examination of the dorsal pelvic ring. Furthermore, better appreciation of intrapelvic soft tissue lesions is possible. In a retrospective study on 53 patients, in 88.7% we had quite helpful and extremely helpful CT examinations, and 90% higher precision in comparison to conventional radiographs.