Finite element analysis of screw fixation versus lateral support plate fixation for Letenneur type Ⅲ Hoffa fracture
Objective To establish three-dimensional model of healthy adult knee joint model,analyze and compare biome-chanical differences between cannulated screw(model A)and lateral support plate combined with screw(model B)in treatment of Letenneur type Ⅲ Hoffa fracture by finite element analysis method.Methods Thin-layer CT images of healthy adult knee joints were collected,the preliminary model was extracted by Mimics 21.0 software,and the model was further smoothed by Geomagic Wrap2021 software.In Solidworks 2023,the necessary internal fixation components for 2 kinds of Letenneur type Ⅲ Hoffa fracture models were created,the parts were assembled in Solidworks 2023 software,and fracture internal fixation treatment was simulated.The model was meshed in Ansys 2021 software,and the validity of knee joint model was verified,the two internal fixation models were simulated to apply human single-leg standing load,the Von mises stress distribution,fracture terminal and screw displacements of the two models were calculated.The biomechanical effects of the two models were compared.Results ①After applying 134 N forward force to posterior upper terminal of tibia,tibial inter-condylar eminence shifted forward by 4.52 mm,which was similar to the previous results.②The maximum displacement of bone fragment in Model A was 0.452 mm,which was larger than that in Model B(0.357 mm).③The maximum stress of internal screw in model A was 73.3 MPa,and was 119 MPa in model B,the screw stress in model B was higher than that in model A.The screw stress in model A showed decreasing trend from distal to proximal,and screw stress in model B showed U-shaped from distal to proximal.④The maximum displacement of screw in model A was 0.52 mm,and that in model B was 0.69 mm.The trend of screw displacement in model A and model B both increased gradually from distal to proximal,and screw displacement in model A and model B were similar.Conclusion It is demonstrated that the cannulated screw combined with lateral plate show better biomechanical effect in treatment of Letenneur type Ⅲ Hoffa fracture,which is more conducive to postoperative reha-bilitation of patients.
Hoffa fracturefinite element analysiscannulated screwplates
NETL
NSTL
万方数据
