基于双源CT的前交叉韧带重建术后隧道位置评估及移植物应力的有限元分析

发布时间：2018-05-14 10:31

本文选题：双源CT + 前交叉韧带　；参考：《第四军医大学》2015年硕士论文

【摘要】：实验一双源CT测量前交叉韧带单束重建术后隧道位置的临床研究目的:应用双源CT(Dual-source computer tomography,DSCT)测量前交叉韧带(Anterior cruciate ligament,ACL)单束重建术后胫骨、股骨隧道位置,并对隧道位置进行评价。方法:对2013年1月至2014年6月我科收治的92例(男64例,女28例,平均年龄31.2岁)ACL单束重建患者术后膝关节进行双源CT扫描并行三维重建,应用Adobe Photoshop CS6软件圈画隧道中心并采用Lorenz法测量胫骨隧道中心点相对位置百分比(Tx,Ty),采用Bernard四格表法测量股骨隧道中心点相对位置百分比(Fx,Fy)。结果:Tx平均为(54.54±3.42)%,Ty平均为(39.58±6.72)%,Fx平均为(28.98±6.51)%,Fy平均为(28.04±8.70)%。男、女性及左、右膝之间Tx、Ty、Fx、Fy的差异均无统计学意义(P0.05)。结论:双源CT能够清晰,三维显示ACL术后隧道,可以用来评估隧道位置,为改进ACL损伤后的手术方式及个体化解剖重建提供帮助。实验二半腱肌腱应力松弛实验及弹性模量的测量计算目的:研究新鲜尸体膝关节半腱肌腱的粘弹性力学特性,计算单股半腱肌腱弹性模量,为有限元分析提供生物力学参数。方法:尸体标本上取出半腱肌腱,修整成尺寸统一的试样,应用力学试验机对肌腱施加拉伸载荷,当位移达到预定行程时保持位移不变,观察力的变化。结果:得到了半腱肌腱应力松弛实验数据,绘制了载荷-位移曲线及载荷-时间曲线,经计算得到了单股半腱肌腱的弹性模量E=143.46±8.35 MPa。结论:半腱肌腱具有粘弹性材料典型的应力松弛生物特性,其粘弹性力学特性使其可以作为ACL移植物应用。实验三基于双源CT的前交叉韧带重建术后胫股关节有限元模型的建立及移植物应力的有限元分析目的:基于双源CT断层图像构建ACL单束重建术后胫股关节有限元模型,分析移植物应力大小及分布。方法:应用双源CT对1例ACL单束重建术后患者右膝关节进行伸直位扫描,获得断层数据,将此数据导入MIMICS及GEOMAGIC STUDIO软件建立三维几何模型,将几何模型导入ANSYS软件并划分网格,进行材料赋值后建立ACL单束重建术后胫股关节有限元模型,利用模型模拟前抽屉试验时移植物应力的分布及大小。结果:1.成功利用双源CT断层数据、MIMICS及GEOMAGIC STUDIO软件构建了ACL单束重建术后胫股关节三维实体模型。2.利用ANSYS软件建立了ACL单束重建术后胫股关节三维有限元模型,对该模型进行了网格划分,边界约束及材料赋值。3.应用有限元模型分析了前抽屉试验下移植物的应力分布及大小。结论:1.应用双源CT及MIMICS、GEOMAGIC STUDIO等逆向工程软件可以准确地建立三维实体模型,可用来观察ACL重建术后移植物空间位置。2.将三维实体模型导入有限元分析软件ANSYS并进行网格划分,边界约束及材料赋值后可以进行移植物应力的分析。3.移植物股骨隧道内口附着处应力分布较大,理论上为其最容易发生断裂的部位。
[Abstract]:Objective: to measure the location of tibia and femur tunnel after single bundle reconstruction of anterior cruciate ligament (ACL) by double source CT. Objective: to evaluate the location of tibia and femur tunnel after single bundle reconstruction of anterior cruciate ligament (ACL) by double source CT(Dual-source computer tomographygraphy (DSCT). Methods: from January 2013 to June 2014, 92 patients (64 males and 28 females) with an average age of 31.2 years old with single bundle reconstruction of ACL, underwent dual source CT scan and 3D reconstruction. Adobe Photoshop CS6 software was used to circle the center of the tunnel and the relative position percentage of the center point of tibial tunnel was measured by Lorenz method. The relative position of the center point of femur tunnel was measured by Bernard four-grid table method. Results the average Tx of TX was 54.54 卤3.42 and Ty was 39.58 卤6.72 and Fx was 28.98 卤6.51 and the average Fy was 28.04 卤8.70. There was no significant difference between male, female, left knee and right knee in TxTX type FX Fy (P 0.05). Conclusion: Dual-source CT can clearly display the tunnel after ACL, and can be used to evaluate the location of the tunnel. It can be used to improve the operation mode and individual anatomical reconstruction after ACL injury. Experimental stress relaxation experiment and calculation of Elastic Modulus of the second half tendon objective: to study the viscoelastic properties of the semitendinosus tendon of the knee joint of fresh cadavers and to calculate the elastic modulus of the semitendinosus tendon of the single strand so as to provide biomechanical parameters for finite element analysis. Methods: the semitendinosus tendon was taken out from the cadaveric specimen, and the specimen was trimmed into a uniform size sample. The tensile load was applied to the tendon by mechanical testing machine, and the displacement remained the same when the displacement reached the predetermined stroke, and the change of the observation force was observed. Results: the experimental data of stress relaxation of semitendinosus tendon were obtained, the load-displacement curve and load-time curve were plotted, and the elastic modulus of single-stranded semitendinosus tendon (E) 143.46 卤8.35 MPa was calculated. Conclusion: the semitendinosus tendon has the typical stress relaxation biological properties of viscoelastic material, and its viscoelastic mechanical properties make it can be used as ACL graft. Experiment 3: establishment of tibiofemoral joint finite element model and finite element analysis of graft stress after anterior cruciate ligament reconstruction based on dual-source CT objective: to construct tibiofemoral joint finite element model after ACL single-bundle reconstruction based on dual-source CT tomography. The size and distribution of graft stress were analyzed. Methods: double source CT scan was performed on the right knee joint of one ACL patient after single bundle reconstruction. The data were imported into MIMICS and GEOMAGIC STUDIO software to establish 3D geometric model, and the geometric model was imported into ANSYS software and divided into meshes. The finite element model of tibiofemoral joint after ACL single bundle reconstruction was established after material assignment. The distribution and size of graft stress during anterior drawer test were simulated by the model. The result is 1: 1. The three-dimensional solid model of tibiofemoral joint after ACL single-bundle reconstruction was successfully constructed by using dual-source CT tomography data mics and GEOMAGIC STUDIO software. The three-dimensional finite element model of tibiofemoral joint after ACL single bundle reconstruction was established by using ANSYS software. The model was meshed with boundary constraints and material assignment. 3. Finite element model was used to analyze the stress distribution and size of the moving plants in front drawer test. Conclusion 1. Using reverse engineering software such as dual-source CT and Mimics Gomagic STUDIO, 3D solid model can be built accurately, and it can be used to observe the space position of grafts after ACL reconstruction. The three-dimensional solid model is introduced into the finite element analysis software ANSYS and meshed. After the boundary constraints and the material value are assigned, the graft-stress can be analyzed. 3. The stress distribution at the inner end of the femoral tunnel is large, which is the most prone to fracture in theory.
【学位授予单位】：第四军医大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R687.2

【参考文献】