目的 基于膝关节冠状面对线(coronal plane alignment of the knee,CPAK)分型方法建立膝关节有限元模型,分析不同分型膝关节生物力学特征.方法 基于6名健康志愿者膝关节CT扫描数据建立有限元模型.其中男5名,女1名;年龄23～25岁,平均24.2岁.左、右膝各3名.CPAK分型分别为Ⅰ～Ⅵ型.在材料属性、边界条件、轴向载荷相同条件下,对膝关节有限元模型进行生物力学仿真分析,基于Von Mises应力云图及位移云图,比较不同分型膝关节半月板、胫骨软骨、股骨软骨峰值应力及半月板位移.结果 构建的膝关节有限元模型经验证有效,应力和位移结果与既往文献相符.在1000N轴向载荷下,应力云图显示CPAK Ⅲ型半月板与胫骨软骨内、外侧应力分布差异最大,外侧峰值应力分别为9.9696 MPa和2.602 7 MPa,分别是内侧的173％和165％.Ⅳ型股骨软骨内、外侧峰值应力差异最大,内侧达外侧的221％.位移云图显示除Ⅲ和Ⅵ型外,内侧半月板位移均大于外侧.Ⅲ型半月板内、外侧位移差异最大,外侧达内侧的170％.结论 同一关节线倾斜角类型中,内翻位、中立位膝关节内、外侧应力分布相较于外翻位更均匀.同时远端顶点有助于减轻内翻膝关节内、外侧应力分布不均,但会增加外翻膝关节内、外侧应力分布不均.
Biomechanical study of knee joint based on coronal plane alignment of the knee
Objective To establish a finite element model of the knee joint based on coronal plane alignment of the knee(CPAK)typing method,and analyze the biomechanical characteristics of different types of knee joints.Methods The finite element models of the knee joint were established based on CT scan data of 6 healthy volunteers.There were 5 males and 1 female with an average age of 24.2 years(range,23-25 years).There were 3 left knees and 3 right knees.According to the CPAK typing method,the knees were rated as types Ⅰ to Ⅵ.Under the same material properties,boundary conditions,and axial loading,biomechanical simulations were performed on the finite element model of the knee joint.Based on the Von Mises stress nephogram and displacement nephogram,the peak stresses of the meniscus,femoral cartilage,and tibial cartilage,and the displacement of the meniscus were compared among different types of knee joints.Results The constructed finite element model of the knee joint was verified to be effective,and the stress and displacement results were consistent with previous literature.Under the axial load of 1 000 N,the stress nephogram showed that the stress distribution of the medial and lateral meniscus and tibial cartilage of CPAK type Ⅲ knee joint was the most uneven.The peak stresses of the lateral meniscus and tibial cartilage were 9.969 6 MPa and 2.602 7 MPa,which were 173％and 165％of the medial side,respectively.The difference of peak stress between the medial and lateral femoral cartilage was the largest in type Ⅳ knee joint,and the medial was 221％of the lateral.The displacement nephogram showed that the displacement of the medial meniscus was greater than that of the lateral meniscus except for types Ⅲ and Ⅵ knee joints.The difference between medial and lateral meniscus displacement of type Ⅲ knee joint was the largest,the lateral was 170％of the medial.Conclusion In the same type of joint line obliquity(JLO),the medial and lateral stress distribution of the knee was more uniform in varus and neutral positions than in valgus position.At the same time,the distal vertex of JLO subgroup can help to reduce the uneven medial and lateral stress distribution of varus knee,but increase the uneven distribution of valgus knee.
Coronal plane alignment of the knee typingbiomechanicsfinite element analysis
万方数据
维普
