Numerical study of stress shielding reduction at fractured bone using metallic and composite bone-plate models

Abstract

3D finite element models for a fractured tibia with Stainless Steel (SS) and Carbon/hydroxyapatite (C/HA) bone-plates are analyzed using ANSYS workbench. Plates with different gaps (0.2, 0.4 and 0.7 mm), and a contact plate with no-gap are examined. von Mises stresses along the fracture site and the tibia bone are also studied under the same loading and boundary conditions. The results of stresses have been compared and presented in graphs. It is found that SS and C/HA bone-plate materials with a gap value 0.7 mm provide higher compressive stress along the fracture site and the bone than the other bone plate models. C/HA bone plate achieves more increasing of stresses than SS bone plate. Using C/HA plate increasing the average stresses by 16% along the fracture site and by 38% along the bone at the final healing stage compared to SS plate of the 0.7 mm gap model. Keywords: Stress shielding, Composite bone-plate, Metallic bone-plate, Tibia bone fracture, Finite element analysis