Spine Case 12 Diagnosis

Sacral Fracture

If the diagnosis of sacral fractures is made on plain radiographs, an AP, inlet and outlet view of the pelvis should be obtained.

On radiographs, evaluate the three sacral arcuate lines that form the roofs of anterior sacral foramina and neural grooves. Arcute lines should be symmetrical on the AP view of the pelvis (top image). Asymmetric or discontinuous sacral arcuate lines may be caused by uncomplicated sacral fractures (lower image). If the sacral arcuate lines are disorganized or markedly disrupted, this may indicate a comminuted sacral fracture.

A CT scan further delineates the complexity of the fracture. The fracture is frequently more extensive on CT imaging than depicted on plain films.