Optimizing Tibia implants: Comparative study of lattice designs and material performance under gait cycles

This study advances orthopaedic implant design by examining the impact of lattice structures on gait cycles and integrating biomimicry principles for superior patient outcomes. Using Finite Element Analysis (FEA), three lattice designs; Face Centred Cubic (FCC), Body Centred Cubic (BCC), and a hybrid Face-Body Centred Cubic (FBCC) were evaluated with materials including Ni-Ti Shape Memory Alloy, TNTZ Alloy, and AZ91D Alloy for its suitability in orthopaedic implants. AZ91D emerged as the optimal material based on compression analysis, offering the best balance of strength and weight. Tibia bone implants made from AZ91D were tested under various gait cycle conditions, including loading-level knee bending, 20% bending, and 30% bending, where the FBCC structure outperformed others due to its enhanced load transfer capabilities. Porosity effects were analysed by varying strut diameters between 0.3 mm and 0.6 mm, resulting in a 40% stiffness difference compared to natural bone, affirming its suitability for biomimetic applications. This innovative approach achieves an ∼86% weight reduction compared to titanium-based implants, significantly enhancing comfort, reducing physical strain, and improving mobility for amputees. By leveraging advanced topology optimisation and material science, this research provides valuable insights into lightweight and high-performance orthopaedic implant development.