title: An investigation of the inelastic behaviour of trabecular bone during the press-fit implantation of a tibial component in total knee arthroplasty.
abstract: The stress distribution and plastic deformation of peri-prosthetic trabecular bone during press-fit tibial component implantation in total knee arthroplasty is investigated using experimental and finite element techniques. It is revealed that the computed stress distribution, implantation force and plastic deformation in the trabecular bone is highly dependent on the plasticity formulation implemented. By incorporating pressure dependent yielding using a crushable foam plasticity formulation to simulate the trabecular bone during implantation, highly localised stress concentrations and plastic deformation are computed at the bone-implant interface. If the pressure dependent yield is neglected using a traditional von Mises plasticity formulation, a significantly different stress distribution and implantation force is computed in the peri-prosthetic trabecular bone. The results of the study highlight the importance of: (i) simulating the insertion process of press-fit stem implantation; (ii) implementing a pressure dependent plasticity formulation, such as the crushable foam plasticity formulation, for the trabecular bone; (iii) incorporating friction at the implant-bone interface during stem insertion. Simulation of the press-fit implantation process with an appropriate pressure dependent plasticity formulation should be implemented in the design and assessment of arthroplasty prostheses.
authors.affiliation: Department of Mechanical and Biomedical Engineering, National University of Ireland, Galway, Ireland; National Centre for Biomedical Engineering Science, National University of Ireland, Galway, Ireland.
authors.forename: N
authors.initials: N
authors.lastname: Kelly
authors.forename: D T
authors.initials: DT
authors.lastname: Cawley
authors.forename: F J
authors.initials: FJ
authors.lastname: Shannon
authors.forename: J P
authors.initials: JP
authors.lastname: McGarry
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D004548:Elasticity; D008422:Materials Testing; D011140:Polyurethanes; D011312:Pressure; D019919:Prosthesis Implantation / Q000379:methods*; D013977:Tibia / Q000601:surgery*
chemical_list: D011140:Polyurethanes; C028279:polyurethane foam
keywords: CFI; CFV; E; Finite element analysis; K; PU; Polyurethane foam; Press-fit implantation; Pressure dependent yielding; TKA; Total knee arthroplasty; Trabecular bone plasticity; VM; apparent Young's modulus; apparent yield stress; compression yield stress ratio; crushable foam with isotropic hardening; crushable foam with volumetric hardening; elastic Poisson's ratio; friction coefficient; plastic Poisson's ratio; polyurethane foam; total knee arthroplasty; von Mises; μ; ν(e); ν(p); σ(y)