肥胖患者膝关节置换中胫骨延长杆对胫骨应力分布影响的有限元研究

发布时间：2018-03-09 12:09

本文选题：胫骨延长杆　切入点：有限元分析　出处：《郑州大学》2017年硕士论文　论文类型：学位论文

【摘要】：目的随着人民生活水平的提高,患有膝关节骨性关节炎的肥胖患者人群的数量逐渐增加。膝关节置换术是治疗骨性关节炎的有效手段。在肥胖患者进行膝关节置换过程中使用胫骨延长杆可以有效降低术后无菌性松动的发生率。但是,对不同长度的胫骨延长杆对胫骨应力分布的影响研究较少。本研究旨在通过有限元素分析的方法研究患有骨性关节炎的肥胖患者在膝关节置换中,胫骨侧使用不同长度延长杆对胫骨平台应力分布以及胫骨应力遮挡的影响。方法1.对一女性骨性关节炎患者行胫骨计算机断层扫描,利用Mimics15.0进行影像学数据处理以及三维重建,导出其胫骨三维实体模型并以STL格式导入Unigraphics NX8.5中按照膝关节置换操作进行模拟手术,建立其胫骨截骨后的三维实体模型,并在软件中导入膝关节假体胫骨侧及30mm、60mm和100mm延长杆。通过FEMAP有限元软件对各组三维模型进行网格划分、各部分材料属性赋值、确定坐标系、加载载荷和边界条件,建立三维动态有限元模型。2.虚拟胫骨假体与不同长度延长杆配对的模型,对照组A为标准胫骨平台,平台下端无延长杆连接,实验组B用标准胫骨平台假体与30mm延长杆连接。实验组C为标准胫骨平台假体与60mm延长杆连接。实验组D为标准平台假体与100mm延长杆相连接。各组模型相互独立。通过FEMAP有限元软件计算四组三维动态有限元模型假体接触的生物力学特性。结果1.在标准平台与3组不同长度的实验组中,各组胫骨假体翼面与平台底面相交外侧局部应力最高。胫骨假体翼两侧应力较高,在标准平台上(0mm)其应力最大,44.32±2.26MPa。在使用30mm、60mm、及100mm延长杆时,应力值分别为37.93±1.25MPa、34.62±3.85MPa和36.70±2.97MPa。三组实验组比对照组应力值明显减小,差异有统计学意义(P0.05),各组实验组之间无统计学差异。2.在对照组A、实验组B与实验组C的模型中,胫骨平台内侧应力分别指4.09±0.85MPa,3.98±0.73MPa和3.88±0.80MPa,三组模型中差异无统计学意义,而在实验组D(100mm延长杆)中,内侧平台应力明显下降为1.55±0.29MPa,与其他其他三组之间差异有统计学意义。在对照组A和实验组B模型中,胫骨后侧平台所受应力为11.68±1.01MPa和10.34±2.05,两组之间差异有统计学意义(P0.05),A、B两组分别与实验组C、D有在后侧平台应力上差异有统计学意义(P0.05)。实验组C、D之间后侧平台之间无明显统计学差异。3.在对照组A(0mm标准平台)中,距离胫骨平台24.2cm处应力达到峰值,为43.3MPa。在实验组模型中,延长杆的使用并没有改变这种轴向传导应力模式,但将应力峰值的位置向远端传导,使用30mm、60mm和100mm延长杆时应力峰值逐步增加,分别达到60.52MPa、66.31MPa和78.61MPa,其位置距离胫骨平台分别为26.6cm、28.3cm和30.6cm。4.三个实验组中,不同长度的延长杆置换后胫骨近端骨皮质的应力相应减小,以100mm延长杆组减少最为显著。100mm延长杆组中应力遮挡较大的区域位于距离基座6cm以内,最大达82.39%;60mm延长杆组中,应力遮挡最大值的区域距离基座6cm以内,最大67.83%;30mm延长杆中,最大应力遮挡区域与基座距离2cm以内,最大应力遮挡率为39.48%。三者具有统计学差异。结论延长杆的使用可以在一定程度上分散胫骨平台应力;延长杆均对胫骨近端形成不同程度的应力遮挡,较长延长杆更为明显;延长杆使应力向胫骨远端传导,延长杆较长时,会使胫骨中下段应力集中,增加术后胫骨中下段疼痛发生率;膝关节置换中,增加延长杆对胫骨平台前侧和外侧应力无明显影响,较长延长杆会分散胫骨平台内侧应力,而使用较短延长杆就可以明显减少胫骨平台后侧应力。
[Abstract]:Objective: with the improvement of people's living standard, the number of people with osteoarthritis of the knee in patients with obesity population increased gradually. Knee arthroplasty is an effective therapy for osteoarthritis of knee replacement. The use of tibial lengthening rod can effectively reduce the incidence of aseptic loosening and low postoperative in obese patients. However, for different lengths of tibia lengthening rod of tibial should be less studied stress distribution. The purpose of this study is to research methods through the finite element analysis of the patients with osteoarthritis of the knee arthroplasty in obese patients, the tibia using different length extension rod stress distribution and tibial stress shielding on tibial plateau. Methods 1. the female osteoarthritis underwent tibial computed tomography, using Mimics15.0 imaging data processing and 3D reconstruction, 3D model is derived from the tibia Taking the STL format into Unigraphics NX8.5 in accordance with the knee joint replacement operation for surgical simulation, establish the 3D model of the tibial osteotomy, and imported knee prosthesis tibial and 30mm in software, 60mm and 100mm. The extension rod is used to mesh the three-dimensional model of each group by FEMAP finite element software, the material properties the assignment, determine the coordinates, load and boundary conditions, the establishment of three-dimensional dynamic finite element model of.2. virtual tibial prosthesis with different length extension rod matching model, the control group A as standard tibial plateau, the lower end of long rod connecting platform, the experimental group with B prosthesis and 30mm standard tibial extension rod connection. The experimental group C as the 60mm standard tibial plateau prosthesis and extension rod connection. The experimental group D prosthesis and 100mm standard platform extension rod is connected. All models are independent of each other. Through the finite element software FEMAP calculation of the four group of three The biomechanical properties of prosthesis dimensional dynamic finite element model of contact. Results in the 1. standard platform and 3 groups of different length in the experimental group, each group of tibial wing surface and the bottom surface of the platform outside the intersection of local stress. The highest tibial prosthesis wing on both sides of the stress is higher in the standard platform (0mm) the maximum stress, 44.32. 2.26MPa. in the use of 30mm, 60mm, and 100mm extension rod, the stress values were 37.93 + 1.25MPa, 34.62 + 3.85MPa and 36.70 + 2.97MPa. three group experimental group than the control group significantly reduces stress, the difference was statistically significant (P0.05), the experimental group showed no significant difference between the groups of.2. in the control group A, experiment group B and experimental group C model, medial tibial plateau stress were 4.09 + 0.85MPa, 3.98 + 0.73MPa and 3.88 + 0.80MPa, there was no significant difference between the three groups in the model, while in the experimental group D (100mm extension rod), medial plateau stress decreased to 1.55 + 0.29M Pa, there was statistical significance and other differences between the three groups. In the control group A and experimental group B model, posterior tibial plateau stress was 11.68 + 1.01MPa and 10.34 + 2.05, there were statistically significant differences between the two groups (P0.05), A, B two group were compared with the experimental group C, D there are significant differences in the rear force platform (P0.05). The experimental group C, no statistically significant difference in the control group.3. A between D platform (0mm platform) posterior tibial platform, 24.2cm distance stress peak of 43.3MPa. in the experimental group model, the extension rod is not change the axial stress transmission mode, but the location of peak stress to the distal conduction, using 30mm, 60mm and 100mm extension rod stress peak increased gradually, reached 60.52MPa, 66.31MPa and 78.61MPa, the distance between the tibial plateau were 26.6cm, 28.3cm and 30.6cm.4. three in the experimental group Stress, extension rod after the replacement of different lengths of tibia proximal bone cortex decreased, with prolonged 100mm bar group decreased the most significant prolongation of.100mm stress shielding large area is located in the base within 6cm bar group, up to 82.39%; 60mm extension rod group, within the 6cm region from the base of stress shielding the maximum value of the maximum 67.83%; 30mm extension rod, the maximum stress shielding region and the base distance less than 2cm, the maximum stress shielding rate of 39.48%. three was statistically significant. Conclusion the extension rod can be dispersed in a certain degree of tibial plateau stress; extension rod of the proximal tibia of varying degrees of stress block, long extension rod is more obvious; the extension rod stress conduction to the distal tibia, the extension rod is longer, the lower tibial stress concentration, increased postoperative pain incidence of tibia; knee arthroplasty, increased extension rod There is no significant effect on the tibial plateau's lateral and lateral stresses. Long extension rods will disperse the medial stress of the tibial plateau, while using shorter extension rods can significantly reduce the posterior side stress of tibial plateau.

【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R687.4

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