Computed tomography of the bony pelvis: a protocol for multiplanar imaging. Part II: Trauma.

Fractures of the pelvis are frequently complex, and conventional radiography, including special views, may be inadequate for accurate diagnosis. One must ascertain the integrity of the anterior and posterior columns, hip joint spaces for debris, and the medial walls of the acetabula. Computed tomography (CT) is indicated early in management, whenever initial plain radiographs reveal complex or questionable fractures of any of these structures. I have developed a unique, multiplanar reformatting protocol using oblique reformations of transverse CT images. This allows clear spatial perception of the nature and extent of pelvic fractures. Twelve selected patients with complex pelvic fractures, as determined by conventional and special radiographs, underwent transaxial and multiplanar CT scanning according to the devised protocol, using transverse CT and multiplanar reformation of the pelvis. The planes of reformation are illustrated by drawings, and multiplanar radiographs demonstrate the injuries. Nine of the 12 patients had additional injuries revealed, over and above the abnormalities shown by CT, by the use of the reformatting technique I describe. Also fractures or fracture dislocations of the sacroiliac joints were diagnosed in four of the 12 patients using CT but in six patients when reformatted images were examined.