Three-dimensional Finite Element Analysis Of Fixation Of The Posterior Column Tibial Plateau Fractures With Plates And Screws

Using relevant software to establish the posterior column fracture of the tibial plateau finite element model which fixed with posterior、internal、external、internal and external bilateral plates and screws. To research the distribution of plates and screws stress and the platform displacement of posterior column of the tibial plateau fracture fixation models of four fixed way, which are loaded in different axial loads.A healthy man of 26 years old was chosen to obtain images of the middle-upper segment tibia using SCT scan.Normal x-ray photographs were analyzed to make sure he had no bone diseases.A three-dimensional finite element model(FEM)of the knee joint was developed using Mimics 10.01 digital interactive 3D medical image software. Then establishment the tibial plateau fracture model of posterior columnin in the finite element software MIMICS、HYPERMESH、ABAQUS. Then four three-dimensional finite element models (FEM) of the tibial plateau fracture of the posterior column,which are fixed by four different ways.Based on set boundary and load conditions to simulate a adult, whose weight is 60kg, in the condition of standing (250N), one leg standing (500N), walking (1000N), fast walking (1500N), and to anlysis the displacement of four fixed models of the tibial plateau fracture of posterior column、distribution of stress and the situation of stress of plates and screws.(1)In the MIMICS、HYPERMESH software, four three-dimensional finite element models of the tibial plateau fracture of the posterior column,which are fixed by four different ways,are built.The models are vivid, realistic and close to the clinical practice.(2) With the 250N axial load, the external fixed model’s axial displacement of plateform is 0.180mm, the internal fixed model’s axial displacement of plateform is 0.167mm, the posterior fixed model’s axial displacement of plateform is 0.155 mm, and the internal and external bilateral fixed model’s axial displacement of plateform is 0.125 mm. Four fixed models in axial load for the 500N,1000N,1500N, the external fixed model’s maximum axial displacement are the largest. Compared to the external fixed model’s maximum axial displacement the maximum axial displacement of the internal fixed model is small. Compared to the internal fixed model’s maximum axial displacement the maximum axial displacement of the posterior fixed model is small. While, the value of the maximum axial displacement of the internal and external bilateral fixed model is the smallest.(3) As the loads increase, the stress values of the four fixed by plate and screws models are also increase. The same role in the 500N axial load, the value of the maximum stress, for the external model of plate and screws、the internal model of plate and screws、the posterior model of plate and screws and the internal and external bilateral model of plates and screws, is 50.7MPa,51.1 MPa,51.1 MPa,59 MPa.In a word, the external model’s value of stress of plate and screws is the smallest. Compared to the external model’s value of stress of plate and screws, the value of stress of the internal model of plate and screws is large. Compared to the internal model of plate and screws, the value of stress of the posterior model of plate and screws is large.The value of the stress of the internal and external bilateral model of plates and screws is the larggest.(4) Stress concentration around the convergence at the plate and screws, the screw hole, the corner of the steel plate.(1)Based on using spiral CT scanning imaging technology to acquisite living computer data, using MIMICS software to build three-dimensional model of knee joint is objective and realistic.(2)By using ABAQUS、HYPERMESH and MIMICS software to establish the FEM of tibia fractures of the posterior column and the FEM of fixed by plate and screws is effective and feasible, which can reflect the realistic (3) For the first time, using finite element method to analyze the stability of the tibial plateau fracture of the posterior column, which is fixed by four different plates and screws in the country. The final result indicated:The value of the stress of the internal and external bilateral model of plates and screws is the largest and the maximum axial displacement of the internal and external bilateral fixed model is the smallest, and this method is the most reliable fixation.As a result, the best way to fix the tibial plateau fracture of the posterior column is the internal and external bilateral fixed model.While, if using only single plate to fix the tibial plateau fracture of the posterior column, The value of the stress of the posterior model of plate and screws is the largest and the maximum axial displacement of the posterior fixed model is the smallest, and this method is the most reliable fixation,in a word, the best way to fix the tibial plateau fracture of the posterior column is the posterior fixed model.(4) The spot of the screws passing through fracture line is the dangerous spot in clinic, where the screws easy fracture.The spots of convergence at the plate and screws and the corner of the steel plate are also the dangerous spot in clinic.(5)FEM and other physical biomechanical testing methods have their advantages and disadvantages, both only be combined together to make up for each other’s deficiencies and conduct a comprehensive analysis to arrive at a scientific and reasonable results.(6) The method of FEA was applied to the Orthopedics Biomechanics Analysis of Science, which provides a new way of thinking for Orthopedics of Chinese modern and scientific.