全膝关节置换胫骨平台截骨后倾角对关节接触力的影响  

The influence of different posterior tibial slope on tibio-femoral contact force after total knee arthroplast

作　　者：杜明明 张宽[1,2] 曾纪洲[3] 闫松华[1,2] DU Mingming;ZHANG Kuan;ZENG Jizhou;YAN Songhua(School of Biomedical Engineering,Capital Medical University,Beijing 100069;Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application,Capital Medical University,Beijing 100069;Department of Orthopaedic Surgery,Beijing Luhe Hospital,Capital Medical University,Beijing 101149)

机构地区：[1]首都医科大学生物医学工程学院,北京100069 [2]首都医科大学临床生物力学应用基础研究北京市重点实验室,北京100069 [3]首都医科大学附属北京潞河医院骨关节外科,北京101149

出　　处：《北京生物医学工程》2021年第3期227-232,238,共7页Beijing Biomedical Engineering

基　　金：国家自然科学基金(31771018)、北京市通州区科技计划(KJ2020CX004-05)资助。

摘　　要：目的通过膝关节有限元模型模拟胫骨平台不同截骨后倾角(posterior tibial slope,PTS),计算全膝关节置换(total knee arthroplasty,TKA)后聚乙烯衬垫、胫骨截骨面以及胫骨干处的应力分布,探索胫骨平台不同截骨后倾角对胫股关节接触力的影响。方法根据1例膝骨关节炎患者的下肢CT及MRI图像,建立术前膝关节三维模型,而后进行模拟全膝关节置换,分别建立胫骨平台0°、3°、6°、9°截骨后倾的膝关节有限元模型。在Abaqus中进行仿真计算,选择静止站立进行加载,施加轴向载荷300 N。结果随着胫骨平台截骨后倾角的增加,聚乙烯衬垫内外侧接触合力百分比没有明显变化,但各部位的应力峰值随之增加。聚乙烯衬垫内侧接触应力峰值从0°时的4.51 MPa增加到9°时的6.13 MPa;外侧接触应力峰值从3.57 MPa增加到6.02 MPa。胫骨截骨面处的接触应力峰值从0°时的0.84 MPa增加到9°时的1.09 MPa。胫骨干处的应力峰值从0°时的1.97 MPa增加至9°时的3.23 MPa。结论胫骨平台截骨后倾角的增加会加大聚乙烯衬垫、胫骨截骨面、胫骨干处的应力峰值。应力峰值过大会增加假体磨损及松动的风险,使得术后关节疼痛或假体翻修的可能性加大。胫骨平台截骨后倾角直接影响到术后的膝关节功能,有待于开展大量的相关研究,综合探索截骨规律。Objective To explore the influence of different posterior tibial slopes(PTS)on tibio-femoral contact forces after total knee arthroplasty(TKA)by calculating the stress distribution on tibial polyethylene insert,the bone-implant surface of tibia and tibial shaft.Methods Based on CT and MRI images of a patient with knee osteoarthritis,a three dimensional knee joint model before the surgery was established,and then a TKA was performed.Finite element models of knee joints with PTS of 0°,3°,6°,and 9°during static standing were established,and were analyzed in Abaqus with an axial load of 300N.Results With the increase of PTS,the percentages of the contact force on the medial and lateral sides of the tibial polyethylene insert did not change significantly,but the maximum Von-Mises stress on both sides increased.The maximum Von-Mises stress on medial tibial polyethylene insert increased from 4.51 MPa at 0°to 6.13 MPa at 9°,and increased from 3.57 MPa at 0°to 6.02 MPa at 9°on lateral.The maximum Von-Mises stress on the bone-implant surface of tibia increased from 0.84 MPa at 0°to 1.09 MPa at 9°.The maximum Von-Mises stress on tibial shaft increased from 1.97 MPa at 0°to 3.23 MPa at 9°.Conclusions The maximum Von-Mises stress on tibial polyethylene insert,the bone-implant surface of tibia and tibial shaft increases as the PTS increases after TKA.Stress spikes increase the risk of prosthesis wear and loosening,making joint pain or prosthesis revision more likely after surgery.The PTS directly affects the function of the knee after surgery,and the related studies need to be widely carried out in the future to comprehensively explore the influence of PTS.

关 键 词：全膝关节置换 胫骨平台截骨后倾角 有限元分析 接触应力 应力分布 

分 类 号：R318.01[医药卫生—生物医学工程]