Posterior screw fixation of sacral fractures and sacroiliac dislocations—patient positioning. Anteroposterior, caudal, and cephalad image intensifier projections show drill bit and screw position. (Redrawn from Matta JM, Saucedo T: Internal fixation of pelvic ring fractures, Clin Orthop Relat Res 242:83, 1989; original by Zilbert.) SEE TECHNIQUE 56.9.