• INTRODUCTION
    • The correct usage of preoperative and intraoperative imaging allows fixation of posterior pelvic ring injuries with safely positioned iliosacral screws in the setting of sacral dysmorphism.
  • STEP 1 PREOPERATIVE PLANNING
    • Obtain CT reformats along the longitudinal axis of the sacrum to determine the orientation and diameter of the osseous corridor for selection of the ideal screw size, length, and trajectory.
  • STEP 2 PATIENT POSITIONING
    • Proper positioning enables reduction and accurate iliosacral screw placement.
  • STEP 3 FRACTURE REDUCTION
    • Reduction of the posterior pelvic ring confers stability; if closed reduction is unsuccessful, proceed with open reduction.
  • STEP 4 IDENTIFICATION OF THE ENTRY POINT
    • The entry point for an iliosacral screw into the upper sacral segment of a dysmorphic pelvis lies more posterior and caudal on the outer table of the posterior ilium than does a transsacral screw; adjust the entry point on the basis of inlet and outlet fluoroscopic views.
  • STEP 5 DRILLING TECHNIQUE
    • Insert a stout cannulated drill bit of 4.5 to 5 mm (depending on the core diameter of the intended iliosacral screw) over the Kirschner wire and drill it into the sacral body under fluoroscopic guidance, in accordance with the preoperative plan.
  • STEP 6 SCREW INSERTION
    • With the guidewire in the ideal position, measure the screw length off the inserted guidewire and advance a tap into the pathway; insert the screw and verify its position on the inlet, outlet, and lateral sacral views.
  • RESULTS
    • Understanding the three-dimensional anatomy of the posterior pelvic ring is essential to successful reduction and fixation of unstable pelvic injuries with use of percutaneous iliosacral screws.IndicationsContraindicationsPitfalls & Challenges.