Gait-Phase Specific FEM Analysis of Knee Loading in Flat and Normal Foot Conditions

Foot posture significantly influences gait mechanics and proximal joint loading, with flat foot deformities altering ground reaction force (GRF) trajectories that may impact total knee replacement (TKR) performance. This study investigates the biomechanical effects of normal foot (NF) and flat foot (FF) gait patterns on knee implant behaviour using finite element analysis (FEA). A validated 3D TKR model was subjected to GRFs representing NF and FF gaits across five key gait phases: heel strike, loading response, mid-stance, terminal stance, and pre-swing. Biomechanical metrics such as contact pressure, contact area, displacement, Von Mises stress, strain, and energy consumption were evaluated. Results indicate that flat foot gait leads to increased mechanical loading on implants, potentially accelerating wear, micromotion, and early failure. These findings highlight the importance of accounting for foot posture in surgical planning and implant selection.Future work will involve experimental validation and incorporation of subject-specific anatomy and dynamic muscle forces for improved clinical relevance.