髋关节囊韧带三维有限元模型的构建及其生物力学意义

Construction of three dimensional finite element model of hip capsular ligament and its biomechanical significance

目的探讨髋关节囊韧带三维有限元模型的构建方法及其生物力学意义。方法选择成人尸体髋关节行CT成像得到髋关节每层横截面图像,提取边界坐标,利用有限元分析软件Un igraph ics NX 2.0和Solid-W orks 2006 SP 0.0构建出髋关节三维有限元模型及人工髋关节假体,并模拟全髋置换术进行装配,将坐股韧带按其术中重建位置进行构建。骨骼与金属模型采用三维十节点四面体实体单元进行网格划分,关节囊六面体连接单元划分,模拟坐位腿交叉动作载荷获取假体撞击过程的角活动度和相应的von M ises应力分布情况。结果所构建的多体连接、大界面划移、大变形的坐股韧带重建有限元模型,客观反映坐股韧带真实解剖形态及生物力学行为,增加坐股韧带重建的模型其关节面的最大主应力值大于仅有金属的模型。结论构建的坐股韧带重建三维有限元模型,为髋关节稳定力学机制及韧带损伤、重建的力学基础研究提供精确模型。关节囊韧带重建具有稳定髋关节的重要作用。

Objective To construct three-dimensional finite element hip joint capsular ligament model and to investigate its biomechanical significance by finite element analysis. Methods A wet hip joint＇s sample from corpse was scaned by CT and all images of every cross-section hip joint＇s layer was obtained, and an hip joint＇s model was cantructed with Unigraphics NX 2. 0 and SolidWorks 2006 SP 0.0 software. The models were assembled when simulated total hip arthroplasty after total hip joint prosthetic and ischiofemoral ligament model had been constructured. Analysis was done on van Mises stress distribution and amount of total hip component when simulated seated leg-crossing manuver. The bone and metal components were meshed as rigid bodies, composed of three-dimensional, all-quadrilateral rigid body elements, and hip joint capsule ligament was fully three-dimensional, hexahedral continuum elements representations. Results The current form of this ischiofemoral ligament＇s reconstruction finite element model provid- ed for multi-body contact, large displacement interfacial sliding, large deformation capsule ligament representation, and clearly reflected the real ischiofemoral ligament＇s anatomy and biomechanical behavior. The maximum Von Mises stresses at the joint interface was more than that for an otherwise identical hardware-only construct. Conclusions The consrucfion of three-dimensional hip joint capsule ligament model provides the precise model for research on mechani- cal behavior of hip joint stability and reconstruction of capsule ligament impaired. The reconstruction of capsule ligament must play a significant role in hip joint stability.