A Finite Element Analysis Of The Supportive Effect Of A New Type Of Rotary Support Plate On Lateral Tibial Plateau Fractures

Objective: To compare the biomechanical characteristics of two internal fixation methods for posterolateral tibial plateau fractures by using finite element analysis and to discuss the feasibility of using new type of rotary support steel plates and screws for internal fixations.Methods: A model of complex tibial plateau fractures was established by using a pendulum saw.The three-dimensional reconstruction was carried out by using finite element analysis,based on which another contrast model was established.Three axial loads of 500 N,1000 N and 1500 N were applied to the two fracture models(A&B)to analyze the maximum displacement,maximum stress and maximum strain of the fracture block and internal fixation system.Results: In model A,the maximum displacement at 500 N,1000 N and1500 N was 0.085797 mm,0.17043 mm and 0.25465 mm,respectively;the maximum stress of bone block was 11.285 MPa,20.648 MPa,29.227 MPa,respectively;the maximum strain of bone block was 0.0012474 mm,0.007435 mm and 0.0035769 mm,respectively.The maximum displacement of the internal fixation was 0.096932 mm,0.18682 mm and 0.27655 mm,respectively;the maximum stress was 69.54 MPa,112.1 MPa,and 155.71 MPa,respectively and the maximum strain was 0.00066228 mm,0.0010676 mm and 0.0014829 mm,respectively.In model B,the maximum displacement of fractures at 500 N,1000N and 1500 N was 0.15675 mm,0.29868 mm and0.44017 mm,respectively;the maximum stress of bone block was 6.5519 MPa,12.575 MPa and 18.842 MPa respectively;the maximum strain of bone block was 0.0032554 mm,0.0074357 mm and 0.012146 mm,respectively.The maximum displacement of screw was 0.14177 mm,0.27109 mm,0.39849 mm,respectively;the maximum stress was 48.916 MPa,92.251 MPa,135.27MPa;the maximum strain was 0.00046608 mm,0.00087893 mm and0.0012887 mm respectively.Conclusions: The new rotary support plate has supportive effects on the lateral fracture block,and the fixation method using this type of plates and screws can replace other methods using the new plates with L-shaped plates.