Finite Element Analysis Of Posterolateral Tibial Plateau Fracture Between The Novel Plate And Other Three Tratiditional Internal Fixation

Objective: We designed a novel type of plate for the treatment of posterolateral tibial plateau fractures.we explored the biomechanical differences with other three traditional internal fixation through the finite element analysis technology,to verify the feasibility of the novel plate for the posterolateral tibial plateau fractures.Methods: We selected four imitation of adult tibia which were produced by American SAWBONES company,the fragement was cut from the posterolateral tibial plateau with a goose saw.Then the four internal fixation were fixed with the novel design of plate,two 6.5mm lag screws,4.5mm inverted type L plate,3.5mm straight plate respectively.Three dimensional reconstruction of the four models were carried out by finite element technology,and the axial load of 500 Newton,1000Newton and 1500 Newton were loaded on each fracture model respectively.To measure the axial displacement of each fragement model and stress distribution and maximum stress of each internal fixation.Results: When the axial load of 500 Newton,the displacement of lag screws were the largest which was 1.425 mm,displacement of posterior straight was minimum which was 0.290 mm,the displacement of the new plate and inverted type L plate were 0.447 mm and 0.358 mm respectively.When the axial load of 1000 Newton,the displacement of lag screws were the largest which was 1.680 mm,displacement of posterior straight was minimum which was 0.580 mm,the displacement of the new plate and inverted type L plate were 0.873 mm and 0.718 mm respectively.When the axial load of 1500 Newton,the displacement of lag screws were the largest which was 1.818 mm,displacement of posterior straight was minimum which was 1.067 mm,the displacement of the new plate and inverted type L plate were 1.309 mm and 1.374 mm respectively.And when the axial load of 500 Newton,the maximum stress the novel design of plate,two 6.5mm lag screws,4.5mm inverted type L plate,3.5mm straight plate,was 132.660 Mpa,321.940 Mpa,100.383 Mpa,321.940 Mpa respectively.Maximum stress of the four internal fixation increased,but the overall trend was consistent with 500 Newton when the axial load was 1000 Newton,1500Newton.Conclusion: The results showed that the maximal displacement of the four kinds of internal fixation are all less than 2 mm in three different loads of 500 Newton,1000Newton,1500 Newton,all in the range of functional recovery after knee surgery.The posterior straight fixation was most reliable,the lag screw had the worst reliability,the novel plate and inverted type L plate to control the displacement of fragement were similar.It showed that the novel design of plate was stable and reliable,and it could provide reliable basis for clinical application.