The Central Entry Point for Infra‐Acetabular Screw Placement: Defining an Anatomical Entry Zone and Evaluating Its Clinical Efficacy

OBJECTIVE: Previous studies have been constrained by a single ideal entry point and a narrow bony corridor, leaving a limited selection of entry points for infra-acetabular screws and resulting in suboptimal surgical efficiency. This study aims to analyze the morphology of the infra-acetabular screw entry zone and evaluate a central entry point zone for optimizing surgical screw placement. METHODS: 3D pelvic models from 100 patients were reconstructed. The entry zone was morphologically analyzed, and its similarity to a standard ellipse was calculated. A clinical comparison was conducted on 20 patients with acetabular fractures, comparing the central entry point technique against the ideal entry point method. RESULTS: The entry zone exhibited a quasi-elliptical shape. The central entry point was consistently located medial and anterior to the ideal entry point. Clinically, the central entry point group demonstrated significantly shorter operative time and fewer x-ray exposures, while screw length and success rate showed no significant difference. CONCLUSION: The infra-acetabular screw entry zone is an elliptical structure. Using the central entry point significantly improves placement efficiency and reduces radiation exposure, offering considerable clinical value.