| 摘要: |
| 目的模拟股骨远端骨折髓内钉与锁定钢板内固定，比较2种常用内固定的效果，并探索其对膝关节生物力学的影响。方法建立精确的膝关节三维有限元模型，在此基础上建立股骨远端A型骨折理想模型、髓内钉内固定手术有限元模型（Ⅰ型模型）和锁定钢板内固定手术有限元模型（Ⅱ型模型）。通过对多个关节屈曲度（0°、60°、90°、120°）的模型加载重力载荷来分析内固定物、关节软骨及半月板的应力变化和股骨远端最大位移等。结果Ⅰ、Ⅱ型模型的内固定物、关节软骨和半月板各有1个最大应力部位，最大应力峰值均出现在关节屈曲90°状态下。股骨远端位移峰值总体随着关节屈曲角度的加大而增加。同样屈曲角度下，胫骨平台软骨、半月板的最大应力值均大于股骨髁软骨，锁定钢板的最大应力值大于髓内钉，Ⅱ型模型的股骨远端最大位移值大于Ⅰ型模型。结论内固定方式有限元分析可以模拟膝关节不同运动状态下的受力情况，有效分析出不同模型中内固定物、关节软骨和半月板在不同运动状态下的生物力学特征。 |
| 关键词: 有限元分析 骨折固定术 股骨 膝关节 |
| DOI： |
| 分类号: |
| 基金项目:慈溪市科技计划项目 |
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| Finite element analysis of intramedullary nail fixation and internal fixation of lockng plate for distal femoral fracture |
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ZUO Chengshi, LI Kaicheng, ZHANG Zhaoguo, CHEN Jianwen
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Cixi Hospital of Traditional Chinese Medicine
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| Abstract: |
| Objective To compare the commonly used internal fixations for distal femoral fractures by finite element analysis. Methods The accurate 3-D finite element model of knee joint was established. On this basis, the ideal model of type A distal femoral fracture and the finite element model of intramedullary nail and locking plate were established and assembled to mimic two internal fixations. The variation of stresses on internal fixator, articular cartilage and meniscus and maximum displacement of distal femur were analyzed by applying load on multiple ranges of flexion (0, 60, 90, 120 degree) of the joint in the model, and the mechanical characteristics and pros and cons of two internal fixations for type A distal femoral fractures were compared. Results There was one site with maximum stress value on internal fixator, articular cartilage and meniscus for each model. All maximum stress peaks occurred at the 90 degree of flexion of the joint. At the same range of flexion, cartilage of tibial plateau and meniscus had greater maximum stress value than cartilage of femoral condyle. The locking plate had greater maximum stress value than the intramedullary nail. The maximum displacement of distal femur was bigger in internal fixation with locking plate than in fixation with intramedullary nail. Conclusion The finite element model mimicking internal fixation can mimic the stresses applied on knee joint at different ranges of motion, which can effectively analyze and compare biomechanical characteristics of internal fixator, articular cartilage and meniscus at different ranges of motions in different models. |
| Key words: Finite element analysis Fracture fixation Femur Knee joint |
