<p>Iliosacral screw osteosynthesis is a widely recognized technique for stabilizing unstable posterior pelvic ring injuries, offering notable advantages, including enhanced mechanical stability, minimal invasiveness, reduced blood loss, and lower infection rates. However, the procedure presents technical challenges due to the complex anatomy of the sacrum and the proximity of critical neurovascular structures. While conventional fluoroscopy remains the primary method for intraoperative guidance, precise preoperative planning using multiplanar reconstructions and three-dimensional volume rendering is crucial for ensuring accurate placement of iliosacral or transsacral screws. Particular attention must be given to the preoperative evaluation of both the iliosacral and transsacral corridors, as anatomical variations may restrict the available space for screw insertion. This review aims to highlight the essential aspects of sacroiliac osteosynthesis, with a focus on the critical role of thorough preoperative planning and its impact on achieving successful surgical outcomes.</p>