Finite Element Analysis Of Locking Screw Assisted Acetabular Cup Fixation

Objective:To analyze the feasibility,superiority and stability of the locking screw-assisted acetabular cup fixation method compared with the traditional fixation method by finite element method.Provide a biomechanical basis for the clinical application of this new technology.Methods:The forward modeling software Solidworks was used to reconstruct the acetabular cup and different screws and assemble them as required.Use the finite element software Analysys workbench to compare the three methods(acetabular cup;acetabular cup and ordinary screw;acetabular cup and locking screw)at different angles(60°;70°;80°).Peak stress changes,changes in the shear force of the acetabular cup and statistical analysis.Results:1.The established finite element model of acetabular cup and screw has good geometric similarity and can be used for finite element analysis.2.The peak stress and shear force of the acetabular cup of the locking screw group are smaller than those of the acetabular cup alone and the common screw.3.The average nodal stress of the locking screw group is higher than that of the traditional group,which can effectively disperse the stress on the acetabular cup.4.The locking screw-assisted acetabular cup fixation method is very stable under different angles,and the stress and shear force changes are very stable,and there is no stress concentration.Conclusion:1.Compared with traditional fixation methods(press-fit,ordinary screw-assisted fixation),locking screws have the following characteristics:(1)Locking screws have been widely used in patients with osteoporosis,trauma,and periprosthetic fractures.Therefore,it is feasible to use this method to assist the fixation of the acetabular cup prosthesis.(2)The locking screw solves the possible shortcomings of ordinary screws in the traditional way,especially when used in complex surgical situations that require high stability,which is more advantageous.(3)It is not easy to have stress concentration in different placement.positions like ordinary screws,which will lead to failure or breakage of the screws,and the overall stability is more stable.2.Part of the evidence is provided to the previous research through the mathematical method to prove whether the auxiliary screw is used in the traditional method is better than the press-fit method.