Fractures of the sacrum and sacroiliac joint: evaluation by computerized tomography with multiplanar reconstruction.

Conventional roentgenographic views of the pelvis provide inadequate assessment of complex bony trauma. Computerized tomography (CT) allows simpler patient positioning, more reliable detection of subtle fractures, better characterization of complex fractures, and detection of associated soft tissue and joint space abnormalities. The addition of multiplanar reconstructions (MPR) provides a better understanding of the pathoanatomy. The sacrum and the sacroiliac joint, traditionally problematic to image, are particularly well defined by CT/MPR. Subtle diastasis and intra-articular fragments are more reliably detected when the transaxial image is supplemented by coronal reconstructions. The degree of comminution and direction of fragment displacement are also best defined by coronal and sagittal formatting. Surgeons often find this protocol useful in preoperative assessment of extent and stability of fractures, and in planning conservative or surgical management.