Abstract:Objective To analyze the differences in the initial stability of an acetabular cup with a Voronoi polyhedral porous structure and a solid acetabular cup and to explore the impact of the Voronoi polyhedral porous layer on the initial stability of the acetabular cup, as well as its role in preventing loosening and dislocation. Methods Voronoi polyhedral porous scaffold structures with 60% and 70% porosities were designed using the Grasshopper software. Specimens of solid and porous acetabular cups with 60% and 70% porosities were manufactured using selective laser melting technology. Lever tests on the acetabular cups were conducted using polyurethane block models under identical conditions, and the maximum lever-out moment, angular displacement, and interface stiffness of the three groups of specimens were analyzed and compared. Results Under the condition of no significant differences in the compression force, for porous acetabular cups with porosities of 60% and 70%, the maximum lever-out moment increased by 278.82% and 320.56%, the angular displacement increased by 194.04% and 269.23%, respectively, and the interface stiffness increased by 18.58% and 7.88%, respectively, compared with that of solid acetabular cups. After the lever-out tests were completed, significant wear was observed within the polyurethane block hemisphere cavity using the porous acetabular cups. Conclusions The initial stability indicators of acetabular cups with a Voronoi polyhedral porous structure were higher than those of solid acetabular cups, indicating that the Voronoi polyhedral porous layer can enhance the initial stability of the acetabular cup. These results provide a reference for designing and selecting acetabular components.