INTRAMEDULLARY NAIL OR LOCKING COMPRESSION PLATE FOR FIXING A FRACTURED DISTAL TIBIA: FINITE ELEMENT ANALYSIS ALONG WITH AN ADAPTATION MODEL

Abstract

Intramedullary (IM) nailing and plating are two major options for the treatment of distal tibial fractures; each method has its own pros and cons. Bone loss due to IM nailing or plating can be a serious concern, which may lead to the premature failure of the implants. Thus, investigating bone remodeling in response to orthopedic implantation is of paramount importance for the purpose of designing more efficient prostheses. The main goal of this study was to predict the effects of nailing and plating on the bone apparent density distribution in tibia, through use of the finite element method (FEM) along with a bone remodeling model. To this end, three-dimensional geometry of tibia, with properties derived from computer tomography (CT) imaging data, IM nail and locking compression plate (LCP) were created. Then, a bone remodeling model and FEM, with physiological-like loading, were combined and implemented using Python programming language. The results showed that both nailing and plating methods cause a reduction in bone apparent density, but the plate affects just the distal part of the tibia, where the implant is present; whereas the IM nail affects almost the whole tibia. Moreover, in agreement with clinical observations, it was found here that the stress shielding effects of the LCP are less pronounced than that of IM nail, in the long term. Stress analysis revealed that the load, to most extent, transferred to IM nail; whereas it transferred to LCP just in the distal part of tibia. On the basis of the results of this work, it might be concluded that plating is a better choice than nailing for distal tibial fracture, from the bone remodeling point of view.