Tear-drop technique in iliac screw placement: a technical analysis

BACKGROUND: Instrumentation of the lumbosacral region is one of the more challenging regions due to the complex anatomical structures and biomechanical forces. Screw insertion can be done both navigated and based on X-ray verification. In this study, we demonstrate a fast and reliable open, low exposure X-ray-guided technique of iliac screw placement. METHODS: Between October 2016 and August 2019, 48 patients underwent sacropelvic fixation in tear-drop technique. Screw insertion was performed in open technique by using an X-ray converter angulated 25-30° in coronal and sagittal view. The anatomical insertion point was the posterior superior iliac spine. Verification of correct screw placement was done by intraoperative 3D scan. RESULTS: In total, 95 iliac screws were placed in tear-drop technique with a correct placement in 98.1%. CONCLUSIONS: The tear-drop technique showed a proper screw position in the intraoperative 3D scan and therefore may be considered an alternative technique to the navigated screw placement.