Development of a Patient-Specific Finite Element Analysis for Uncemented Total Hip Arthroplasty: A Step Towards Objective Surgical Planning

Abstract Purpose Aseptic loosening and intraoperative periprosthetic fractures (IOPPFs) are major complications in uncemented total hip arthroplasty (THA). Computational models for assessing primary stability and IOPPF risk preoperatively are limited. This study developed a patient-specific finite element analysis (FEA) framework that replicates stepwise broaching and implantation in uncemented THA, enabling primary stability assessment and providing a foundation for future IOPPF research. Methods A FEA framework was developed using patient-specific femoral geometries and heterogeneous material properties to simulate stepwise broaching and implantation along a defined insertion path. Primary stability was assessed via micromotion under physiological loading. Four case studies were performed to (a) demonstrate the framework using three cadaveric femurs, (b) validate the framework against experimental strain measurements obtained via digital volume correlation (DVC), (c) compare predicted outcomes with a literature-based volumetric expansion model, and (d) assess sensitivity to variations in bone material property models. Results Average post-implantation von-Mises stress ranged from 9.87 to 14.77 MPa, with each broach increasing stress and indicating progressive bone compaction. Primary stability, assessed via bone-implant micromotion (29.10–78.04 µm), remained well below the 150 µm threshold, considered favourable for osseointegration. The proposed framework showed closer agreement with experimental DVC strains and compared to the volumetric-expansion model, halved the prediction error. The analysis also demonstrated limited sensitivity to variations in E-ρ models. Conclusion The proposed FEA method replicates stepwise broaching and implantation in uncemented THA, enabling patient-specific assessment of bone-implant interactions and primary stability, and providing a foundation for preoperative tools to evaluate IOPPF and aseptic loosening risk and guide tailored femoral implant selection.