Osteosynthesis of diaphyseal tibia fracture with locking compression plates: A numerical investigation using Taguchi and ANOVA.

Abstract

Performance of the locking compression plate (LCP) is a multifactorial function. The control parameters of plating, such as geometries, material properties, and physical constraints of the LCP components, affect basic functions associated with the bone fixation, including the extent of stress shielding and subsequent bone remodeling, strength and stability of the bone-LCP construct, and performance of secondary bone healing. The main objectives of this research were as follows: (1) to find the appropriate values of control parameters of an LCP construct to achieve the optimized performance throughout bone healing; and (2) to unravel relationships between LCP parameters and the LCP's performance. Different values for the plate/screw modulus of elasticity (E), plate width (W), plate thickness (T), screw diameter (D), bone-plate offset (O), and screw configuration (C), as six control parameters, were considered at five different levels. Taguchi method was adopted to create trial combinations of control parameters and determining the best set of parameters, which can optimize the overall performance of the LCP. All design cases were analyzed using the finite element method. The optimal set of control parameters consisting of 150 GPa, 12 mm, 4 mm, 5.5 mm, 2 mm, and 123,678 were determined for E, W, T, D, O, and C, respectively. Furthermore, ANOVA was used to rank the most influential parameters on each function of the LCP fixation. In the overall performance of the LCP fixation, E, D, T, C, W, and O showed a contribution percentage of 46%, 22%, 10%, 11%, 8%, and 3%, respectively.