摘要
目的基于人体膝关节CT和MRI图像建立前交叉韧带(anterior cruciate ligament,ACL)断裂和正常膝关节三维实体模型,采用有限元方法研究ACL断裂膝关节在不同屈膝角度对植入假体生物力学性能的影响。方法结合临床单髁置换手术方案植入第3代牛津单髁(OxfordⅢ)假体,其中胫骨假体后倾7°,建立膝关节屈曲0°、30°、60°、90°和120°单髁置换的三维有限元模型,在股骨中心点上施加1 k N压缩载荷,分析5种屈膝角度下股骨假体、半月板衬垫、胫骨假体的应力分布情况。结果膝关节ACL断裂组与正常组在5种屈膝状态下,半月板衬垫的最大主应力在ACL断裂组与正常组之间最大相差幅度为62.5%,在0°、30°、60°和120°屈膝状态下ACL断裂组最大应力均大于正常组;股骨假体在ACL断裂30°时的最大应力明显增加,其余4种屈膝状态下应力的最大增幅为60.81%;胫骨假体在5种屈膝状态下ACL断裂组最大应力比正常组分别增加了19.07%、36.78%、25.69%、-4.38%、51.19%。当ACL断裂后,除屈膝90°外半月板衬垫和胫骨假体上的均布应力均大于正常组,在屈膝30°和120°时对半月板衬垫的磨损较大。结论单髁置换假体的应力分布随膝关节屈曲角度和ACL功能的变化而存在差异,ACL断裂组应力整体趋势大于ACL正常组,且应力集中于内侧区域,在屈膝120°时应力最大,磨损最为明显。研究结果为临床膝关节ACL断裂单髁假体置换的手术方案和半月板假体的优化设计提供理论依据。
Objective To establish the three-dimensional(3 D)solid models of the knee joint with anterior cruciate ligament(ACL)fracture and the normal knee joint based on CT and MRI images of human knee joints,so as to explore influences of the knee joint with ACL fracture at different knee flexion angles on its mechanical properties.Methods Combined with the unicompartmental knee arthroplasty(UKA),an Oxford III prosthesis was implanted and the tibial prosthesis was inclined backward by 7°.The 3 D finite element models for UKA at knee flexion of 0°,30°,60°,90°and 120°were established,with application of 1 kN compressive load on the femur center,to analyze stress distributions of the meniscus cushion,femoral and tibial prosthesis at different knee flexion angles.Results For both knee ACL fracture group and normal knee group under five knee flexion states,the maximum principal stress of the meniscus liner was statistically different,with the maximum difference of 62.5%between two groups.At 0°,30°,60°and 120°knee flexion,the maximum stress in the ACL fracture group was significantly higher than that in the normal knee group.At 30°knee flexion,the maximum stress of the femoral prosthesis in the ACL fracture group increased significantly.The maximum increase under the other four knee flexion states was 60.81%.Compared with the normal knee group under five knee flexion states,the maximum stress of the tibialprosthesis in the ACL fracture group was increased by 19.07%、36.78%、25.69%、-4.38%、51.19%,respectively.In the ACL fracture group,the uniform stress on the meniscus liner and the tibial prosthesis were higher than that in the normal group except at 90°knee flexion.Greater damage could be caused to the meniscus liner at 30°and 120°knee flexion.Conclusions The stress distribution of unicondylar prosthesis varied with flexion angleof the knee joint and the ACL function.The overall stress of the ACL fracture group was larger than that of the normal knee group,with stress concentrated in the medial area.The maximum stress could be reached at the knee flexion of 120°,with the most obvious wear.The research findings provide a theoretical basis for surgical design of the knee joint ACL fracture in UKA and optimization of the meniscus prosthesis.
作者
李鹏祥
赵改平
夏费一
杨加静
许海飞
马童
凃意辉
LI Pengxiang;ZHAO Gaiping;XIA Feiyi;YANG Jiajing;XU Haifei;MA Tong;TU Yihui(School of Medical Instrument and Food Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Department of Orthopedics,Yang Pu Hospital Affiliated to Tongji University,Shanghai 200090,China)
出处
《医用生物力学》
EI
CAS
CSCD
北大核心
2020年第1期70-76,共7页
Journal of Medical Biomechanics
基金
国家自然科学基金项目(11502146)
上海市自然科学基金项目(15ZR1429600).
关键词
膝关节
前交叉韧带断裂
单髁置换术
生物力学特性
有限元分析
knee joint
anterior cruciate ligament(ACL)fracture
unicompartmental knee arthroplasty(UKA)
biomechanical properties
finite element analysis
