股骨近端防旋髓内钉治疗股骨转子间骨折主钉断钉失效:有限元仿真模型构建及有效性验证  

Nail breakage of proximal femoral nail anti-rotation for treating intertrochanteric fracture:construction and validation of finite element simulation model

作　　者：许隆 曾展鹏[2] 陈梓杰 张严 林梓凌[2,3] Xu Long;Zeng Zhanpeng;Chen Zijie;Zhang Yan;Lin Ziling(First School of Clinical Medicine of Guangzhou University of Chinese Medicine,Guangzhou 510405,Guangdong Province,China;Department of Traumatic Orthopedics,First Affiliated Hospital of Guangzhou University of Chinese Medicine,Guangzhou 510405,Guangdong Province,China;Lingnan Medical Research Center of Guangzhou University of Chinese Medicine,Guangzhou 510405,Guangdong Province,China)

机构地区：[1]广州中医药大学第一临床医学院,广东省广州市510405 [2]广州中医药大学第一附属医院创伤骨科,广东省广州市510405 [3]广州中医药大学岭南医学研究中心,广东省广州市510405

出　　处：《中国组织工程研究》2021年第30期4839-4844,共6页Chinese Journal of Tissue Engineering Research

基　　金：国家自然科学基金项目(81673996),项目负责人:林梓凌。

摘　　要：背景:主钉断钉是股骨近端防旋髓内钉固定后必须翻修的失效类型之一。目前股骨转子间骨折断钉发生的生物力学原因多推断于内固定物的疲劳断裂,但目前仍没有直接的研究或方法来证明断钉发生的力学机制。因此构建股骨近端防旋髓内钉治疗股骨转子间骨折的有限元模型并实现断钉失效的可视化,对研究内固定失效的发生机制具有重要意义。目的:仿真模拟股骨近端防旋髓内钉治疗股骨转子间骨折断钉失效的生物力学过程。方法:选取于广州中医药大学第一附属医院创伤骨科住院治疗的髋部骨折患者1例的CT资料导入Mimics 19.0软件中,初步建立股骨近端三维模型,并在Geomagic Studio软件中进行表面优化处理。在SolidWorks软件中按照股骨近端防旋髓内钉规格参数构建股骨近端防旋髓内钉三维模型,装配组件,然后导入优化的股骨仿真三维模型,将股骨近端防旋髓内钉固定到到股骨近端,建立股骨与股骨近端防旋髓内钉装配模型。将装配模型导入Hypermesh软件对模型进行四面体网格划分,构建AO-31A1.3型(2018版)股骨转子间骨折,设置内固定材料疲劳临界参数及股骨材料参数、加载及边界条件、摩擦系数等,导出K文件在LS-DYNA软件求解。结果与结论:(1)裂纹最先出现于主钉螺旋刀片孔两侧薄弱处;(2)主钉断钉前,其最大Von Mises应力达412 MPa,断裂过程中股骨近端防旋髓内钉应力主要集中于主钉与螺旋刀片相交处及尾钉与主钉相交处;主钉断钉前,股骨应力主要分布于头颈处及大转子进针点周围,断钉过程中股骨最大Von Mises应力为248.3 MPa;(3)螺旋刀片尖端及股骨头在断钉过程中向内翻转成角,位移最明显;(4)与文献进行有效性验证结果提示,此模型能有效仿真股骨近端防旋髓内钉治疗股骨转子间骨折主钉断钉失效过程,主钉薄弱处为应力集中和破坏的重点区域。BACKGROUND:Nail breakage of proximal femoral nail anti-rotation is one of the severe implant failure that must be revised.At present,the biomechanical causes for the nail breakage are mostly inferred from metal fatigue;however,there is still no direct research or method to prove the mechanical mechanism of nail breakage.Therefore,to construct a finite element model of proximal femoral nail anti-rotation in treating intertrochanteric fracture and to realize the visualization of nail breakage are of great significance in studying the failure mechanism.OBJECTIVE:To simulate biomechanical process of the nail breakage of proximal femoral nail anti-rotation in treating intertrochanteric fracture.METHODS:Femoral CT data of a hip fracture patient,who was hospitalized in Department of Traumatic Orthopedics,First Affiliated Hospital of Guangzhou University of Chinese Medicine,were imported into Mimics 19.0 and polished in Geomagic Studio software to reconstruct a three-dimensional finite element model of proximal femur.The proximal femoral nail anti-rotation model was created in SolidWorks based on the specification and matched with the polished femoral model according to the surgical protocol.The proximal femoral nail anti-rotation intramedullary nail was fixed to the proximal femur,and the assembly model of the femur and proximal femoral nail anti-rotation intramedullary nail was established.The component including proximal femoral nail anti-rotation and proximal femur was meshed as tetrahedron and constructed as AO-31 A1.3 type fracture(2018 version)in Hypermesh software.After material contents(including critical fatigue parameter of implants and biomechanical material parameter of femur),loading,boundary condition and friction coefficient were completed,the K file was finally solved in LS-DYNA.RESULTS AND CONCLUSION:(1)Crack first appeared on the weakness on the blade hole of nail.(2)The maximal Von Mises stress of nail reached 412 MPa before breakage.During the crack propagation,stress concentrated at the intersection

关 键 词：骨 髋 骨折 股骨转子 股骨近端防旋髓内钉 断钉失效 生物力学 有限元分析 

分 类 号：R452[医药卫生—治疗学] R363[医药卫生—临床医学]