A quantitative biomechanical study of positive buttress techniques for femoral neck fractures:a finite element analysis  

作　　者：Gang Wang Bin Wang Yong Tang Hui-Lin Yang 

机构地区：[1]Department of Orthopaedics,The First Affiliated Hospital of Soochow University,Suzhou,Jiangsu 215006,China [2]Department of Orthopaedics,Southwest Hospital,Third Military Medical University,Chongqing 400038,China.

出　　处：《Chinese Medical Journal》2019年第21期2588-2593,共6页中华医学杂志（英文版）

基　　金：This study was partially supported by a grant from the Zhejiang Medical Science Foundation of China(No.2019KY682).

摘　　要：Background:Refractory femoral neck fractures cannot be anatomically reduced by closed traction reduction which may affect fracture healing.We evaluated the biomechanical effects of positive,negative,and anatomic reduction of various degrees of displacement in Pauwels I femoral neck fractures by a finite element analysis.Methods:Five reduction models of Pauwels type I femoral neck fracture were established using the Mimics 17.0(Materialize,Leuven,Belgia)and Hypermesh 12.0(Altair Engineering,Troy,MI,USA).According to the degree of fracture displacement,there were three models of positive support,an anatomic reduction model,and a negative 2mm reduction model.Finite element analysis was conducted using the ABAQUS 6.9 software(Simulia,Suresnes,France).The von Mises stress distribution and the stress peak of internal fixation in different models,the displacement between fracture blocks,and the principal strain of the femoral neck cancellous bone model were recorded under the axial stress of 2100 N.Results:The peak von Mises stress on screw of each model was located at the thread of the screw tip.The peak von Mises stress was the lowest at the tip of the anatomic reduction model screw(261.2 MPa).In the positive 4mm model,the von Mises stress peak was the highest(916.1 MPa).The anatomic reduction model showed the minimum displacement(0.388 mm)between fracture blocks.The maximum displacement was noted in the positive 4mm model(0.838 mm).The displacement in the positive 3mm model(0.721 mm)was smaller than that in the negative 2mm model(0.786 mm).Among the five models,the strain area of the femoral neck cancellous bone was mainly concentrated around the screw hole,and the area around the screw hole could be easily cut.Conclusions:Compared with negative buttress for femoral neck fracture,positive buttress can provide better biomechanical stability.In Pauwel type I fracture of femoral neck,the range of positive buttress should be controlled below 3mm as far as possible.

关 键 词：ANATOMICAL reduction FEMORAL NECK fracture Finite element analysis 

分 类 号：R68[医药卫生—骨科学]