Finite Element Analysis on the Biomechanical Stability of TPMS-Based Scaffolds for Large Segmental Femur Bone Defect

Treating segmental bone anomalies in orthopedic surgery, particularly in highly stressed regions caused by fracture, malignancy, or infection, is a difficult procedure. The use of artificial scaffolds in Tissue Engineering has had considerable influence on tissue healing. In the formation of bones, scaffolding should offer mechanical stability, allow cells to grow freely, and encourage cell proliferation. The stiffness and strength of a structure must be carefully constructed in order to manage stress concentration and reduce stress generation in the structure. Simultaneously, appropriate porosity, surface-to-volume ratio, and permeability are essential for biological activities such as bone formation and nutrient supply. The construction of a functional bone scaffold necessitates a careful balancing of all of these characteristics. To attain specified porosity and strength, the traditional method was to analyze each of these factors separately without taking into account their interaction. The objective of this research is to conduct a comprehensive analysis of strength, surface-to-volume ratio, porosity, and design of the Triply Periodic Minimal Surface (TPMS) based scaffold for femur bone defect. The TPMS architecture-based scaffold was built with a porosity of 70% to imitate the original bone characteristics. The Finite Element Method (FEM) was used to simulate uniaxial compression in the structure. With Polylactic acid (PLA) as the biomaterial, the maximum stress and displacement of the scaffold were investigated for different unit cells at 70% porosity levels. The result shows that the design and unit cell size influence strength and displacement.