Computerized tomography in the evaluation and classification of fractures of the acetabulum

Sixty-seven consecutive patients with acetabular injuries were assessed first by conventional roentgenograms and Judet oblique views and then by computerized tomography. The fractures were evaluated with Letournel's classification and reclassified by computerized tomographic views alone. The degree of comminution and displacement was further evaluated by Pennal's classification. Computerized tomograms (CT) presented only one classification change in the Letournel system. CT observations significantly changed Pennal's classification by revealing the degree of comminution of the superior articular surface in 14 of the 67 fractures. CT also delineates the superior articular surface of the acetabulum, the degree of comminution in Letournel's complex fractures, the extent and comminution of posterior wall fractures, and the location of intra-articular fragments in postreduction films of hip dislocations.