Biomechanical substantiation of the choice of the method for fixing unstable fractures of the proximal tibia

Abstract

Aim: To justify the choice of a method for fixing unstable proximal tibial fractures (PTF), to conduct computer simulation of stresses on various metal fixators. Materials and Methods: at the initial stage, a solid 3D model of the lower leg has been created using Solid Works, on the background of anatomical models and CT scans. The model contained the following elements: tibia and fibula, interosseous membrane, ligaments of the proximal and distal tibia syndesmosis, and a modeled proximal tibial fracture. We have subsequently studied 4 models of bone fragments’ fixation with LCP plates and an intramedullary blocking metal rod. Further calculations were performed using the finite element method. Results: computer simulations of stresses on various metal fixators applied to fix a PTF convincingly proved that blocked intramedullary osteosynthesis (BIOS) and LCP plates placed bilaterally are feasible for this category of patients. Conclusions: Deformities and loads observed in the metal fixator, bone tissue and ligamentous apparatus run within normal limits. They are statistically significantly (p ≤ 0.05) lower in models of bone fragments’ fixation with IM nailing and bilaterally placed LCP plates. This evidences the adequate stability of bone fragments’ and these methods of osteosynthesis as a whole, compared to the stains in the same elements of modelled fixation using only one plate – medially or laterally. The results of the study may serve as the background for the development of an algorithm for surgical treatment and rehabilitation of patients with PTF.