全膝关节置换术后三维步态分析与个性化多体动力学建模初步探索

发布时间：2018-06-24 03:12

本文选题：膝关节 + 全膝关节置换术　；参考：《第三军医大学》2017年博士论文

【摘要】：研究背景人工全膝关节置换术(Total Knee Arthroplasty,TKA)是治疗膝关节终末期骨关节炎(Osteoarthritis,OA)的“金标准”,可缓解疼痛,重建运动功能。在前面半个世纪,有关人工关节置换术植入物寿命的研究大多集中于假体材料科学,因此产生了多种理化性能卓越的假体材料。虽然对人工关节材料的研究对进一步延长植入物寿命很有价值,但临床医生逐渐意识到假体几何设计及其对患者运动功能的影响对手术疗效及患者满意度也很重要。尽管仿生学设计、个性化假体的理念不断促进假体设计的改善,但几乎各种研究都认为TKA术后膝关节无法完全达到健康自然膝关节的运动状态。因此,对膝关节置换术患者进行运动学和动力学评估可明确TKA术对关节运动学产生了怎样的影响,为临床诊疗提供参考,并可作为术后疗效评价指标。临床医生和人工关节制造商都希望了解TKA术后患者肢体的运动学与动力学状态,以及TKA假体在人体内的运动情况及力学表现。目前虽然有活体内直接的力学测量方法,但却因技术实施困难,存在难以广泛开展的弊端。计算机模型可以模拟很多实验室无法完成的机械过程及分析运算,成为促进TKA设计和改良的重要工具。随着计算机硬件不断升级发展,计算机三维模型越来越精细,三维模型的动态化力学研究也得以实现。通过建立动态化膝关节三维有限元模型(Finite Element Method Model,FEM Model),模拟TKA术后膝关节活动的力学状态及变化规律成为TKA力学研究的重要手段。然而三维有限元分析最大的问题是实验条件的设置具有较大争议,与假体在人体内的实际受力有较大偏差,更不能实现个性化临床病例的分析。步态分析(gait analysis)则是通过不同手段对个体活动方式进行的检查和评估,是对人体活动的量化。量化性步态分析是辨别正常与异常步态的重要临床工具,已经被长时间应用于临床病情评估、制订治疗策略和治疗效果评价。通过步态检查采集的数据计算关节活动的轨迹和活动中关节的受力情况,可用来间接反映TKA术后关节的运动学与动力学状态。多体系统动力学(multi-bodydynamics,mbd)是研究多体系统运动规律的科学,研究对象一般包括若干个柔性和刚性物体,相互连接构成一个整体结构。人体多体动力学建模可以进行步态周期内肌肉活动和关节接触力的分析,帮助我们理解肌肉协调工作的原理,同时了解骨骼和软组织的受力情况,在建立的模型基础上还可进一步优化改进,完成假体微动分析、假体受力状态分析和体内聚乙烯磨损预测等应用研究。骨骼肌肉多体动力学模型预测的关节力和关节运动可输出至有限元软件进行后续分析,通过该方式获取的应力应变是研究人工膝关节假体磨损的重要参数依据。多体动力学模型考虑了患者骨骼的几何形态、人工关节假体设计,以及关节周围肌肉和韧带的情况,能同时计算出关节运动、关节接触力、肌肉力和韧带力。上述结果参数作为边界条件输入到有限元软件中才能反映假体在人体内的真实受力情况。综上,结合人体多体动力学模型和有限元分析的建模方法可很好地理解人工膝关节的在体受力情况,为改善假体设计和临床病例个案分析提供理论依据。本研究的核心内容分为两个部分:第一部分是采取三维步态分析技术对全膝关节置换术后患者步态参数的改变进行量化对比,以探明tka手术对人体步态和肢体功能的影响,属于观察性研究;第二部分是尝试通过患者骨骼几何模型、假体三维数据和步态分析数据建立个性化骨骼肌肉多体动力学模型,以期能更精确地描述关节活动,并预测关节内受力情况,弥补关节内受力无法在体外测量的缺陷,属于探索性研究。研究方法1、全膝关节置换术后的三维步态分析研究我们使用了捕捉反光标记三维活动轨迹的动作捕捉系统、用于采集地面反作用力的测力台和皮肤表面肌电采集装置进行三维步态数据的采集。采集到的数据包括身体各个部分的相对位置与方向、足与地面的作用力、时间-空间关系和下肢肌肉的阶段性活动。嘱患者以日常行走速度在步道上来回走动,双足均完全踩到测力台为一次有效数据,每位患者采集5至8次有效数据。肌电信号与测力台模拟信号数据通过统一的工作平台同步收集。然后使用cortex实时操作分析软件定义各个光点,提取每个点的三维空间坐标,利用空间几何的方法计算出步态参数,结合测试前采集的患者形态数据进行参数调整与优化。输出结果包括空间参数、关节反作用力、关节活动角度和肌肉活动信号,所有参数在术侧术侧之间对比。2、全膝关节置换术个性化多体动力学建模我们使用了一例接受全膝关节置换术患者的完整数据建立个性化骨骼肌肉多体动力学模型,数据包括ct扫描三维重建获取的骨骼几何模型、三坐标仪扫描获取的人工关节假体三维模型、三维步态分析数据等,基于“依赖于力的运动学”(fdk方法)和弹性基理论,将人工膝关节假体整合到了下肢骨骼肌肉模型中,建立tka术后下肢骨骼多体动力学模型,预测置换后膝关节在步态周期内的屈伸活动、关节力矩及胫股关节和髌股关节的接触力。结果1、全膝关节置换术后的三维步态分析研究步态空间时间参数在术侧与健侧之间的差异都没有统计学意义(p0.05)。术侧髋、膝、踝三个关节的关节反作用力均值都较健侧有所减小,但差异没有统计学意义(p0.05)。与健侧相比,术侧髋关节屈伸活动范围没有改变,但最大屈曲角和最大伸直角都明显较小,且差异具有统计学意义(分别为p=0.039,p0.001);术侧髋关节最大外旋角增大,但差异没有统计学意义(p=0.446),最大内旋角和旋转活动度较健侧都有减小,且差异具有统计学意义(p0.001)。术侧与健侧在膝关节最大屈曲角和屈伸活动度上与健侧没有明显差异(p=0.185,p=0.194),但术侧最大伸直角较健侧增大(即最大伸直度减小),差异具有统计学意义(p0.001);术侧最大外翻角及膝关节内外翻活动范围大于健侧,差异具有统计学意义(p=0.023,p=0.002),最大内翻角在双侧无差异;胫骨最大内旋角在术侧显著减少(p=0.025),但最大外旋角和旋转活动范围在双侧无显著差异。踝关节最大背屈角、最大跖屈角和屈伸活动度在两侧间对比没有显著差异(p=0.286,p=0.780,p=0.151);距下关节的翻转运动在两侧之间存在较大差异,其中术侧最大外翻角和最大内翻角都都比健侧增大(p=0.012,p0.001),翻转活动度显著减小(p0.001)。双侧臀大肌信号没有变化,股内侧肌、乆绳肌在术侧增强,腓肠肌在术侧减弱,差异没有统计学意义(p0.05);胫前肌在术侧减弱,信号峰值的差异有统计学意义(p=0.036)。2、全膝关节置换术个性化多体动力学建模我们成功建立了个性化骨骼肌肉多体动力学模型,预测了置换后膝关节在步态周期内的屈伸活动、关节力矩及胫股关节和髌股关节的接触力。结果发现术侧胫股关节和髌股关节的最大屈曲角度没有明显差异,而最大伸直活动度都较健侧降低。术侧膝关节三个方向力矩较健侧均呈现增高的趋势,其中屈(伸)力矩峰值增高约59.2%,内收(外展)力矩增高约18.6%,内旋(外旋)力矩增高趋势最低,约3.5%。术侧胫股关节和髌股关节接触力较健侧降低,其中胫股关节下降约5.8%,髌股关节下降约20.5%。结论1、采取了基于红外动作捕捉的三维步态分析技术对全膝关节置换术后患者步态状态进行了分析。结果显示TKA没有对步态空间-时间参数产生影响,换言之TKA术后12个月后患者行走功能基本恢复正常;但关节运动结果显示术侧膝关节较患侧存在一定的伸直受限,术后膝关节内外翻运动和内外旋运动同样产生了改变,进而引发髋关节、踝关节的运动学继发改变。表面肌电检测结果提示患侧股四头肌和乆绳肌活动加强,提示TKA术后膝关节稳定减弱,需要调动更多的肌肉来维持关节的动态平衡。三维步态分析作为一种客观性、量化性的评测手段,非常适合作为现行临床评估的补充,为临床决策提供更多额外信息。2、基于FDK方法和弹性基理论,将人工膝关节假体整合到了下肢骨骼肌肉模型中,实现了精确的下肢骨骼建模,考虑了关节周围韧带的稳定作用,预测了TKA术后膝关节运动、胫股关节接触力和髌股关节接触力。结果发现术侧胫股关节和髌股关节的最大屈曲角度没有明显差异,而最大伸直活动度都较健侧降低;术侧膝关节三个方向力矩较健侧均呈现增高的趋势;术侧胫股关节和髌股关节接触力较健侧降低。该模型在进一步优化之后可推广到任何个性化人工膝关节置换术后的生物力学研究中,具有较好的通用性,为临床结果评估、假体设计、假体磨损分析等研究提供有效的途径和方法。
[Abstract]:Background artificial total knee arthroplasty (Total Knee Arthroplasty, TKA) is a "gold standard" for the treatment of end stage osteoarthritis of the knee (Osteoarthritis, OA), which can relieve pain and reconstruct motor function. In the first half of the century, the study of implant life for artificial joint replacement was mostly focused on prosthesis material science. Although the study of artificial joint materials is of great value to further prolonging the life span of the implant, clinicians gradually realize that the geometric design of the prosthesis and its effect on the movement function of the patient are very important to the surgical effect and patient satisfaction. There is a constant improvement in the design of the prosthesis, but almost all kinds of studies suggest that the knee joint can not fully achieve the healthy and natural knee joint movement after TKA. Therefore, the kinematic and dynamic assessment of the patients with knee arthroplasty can determine the effect of TKA on the kinematics of the joint, and provide reference for clinical diagnosis and treatment, and can provide reference for the clinical diagnosis and treatment. As an evaluation index of postoperative curative effect, both clinicians and artificial joint manufacturers want to know the kinematics and dynamics of the limbs of the patients after TKA, as well as the movement and mechanical performance of the TKA prosthesis in the human body. Although there is a direct mechanical measurement in the living body, it is difficult to carry out a wide range of techniques because of the difficulties in the implementation of the technique. The computer model can simulate the mechanical process and analysis of many laboratories which can not be completed. It has become an important tool to promote the design and improvement of TKA. With the continuous upgrading and development of computer hardware, the three-dimensional model of the computer is becoming more and more fine, and the dynamic mechanical research of the 3D model is also realized. The three-dimensional finite element model (Finite Element Method Model, FEM Model) is an important means to simulate the mechanical state and change of the knee joint activities after TKA operation. However, the biggest problem of the three-dimensional finite element analysis is that the setting of the experimental conditions is very controversial, and the actual force of the prosthesis in the human body is much more deviant from the actual force of the prosthesis. The analysis of individual clinical cases can not be realized. Gait analysis (gait analysis) is an examination and evaluation of individual activity by different means. It is the quantification of human activity. Quantitative gait analysis is an important clinical tool to distinguish normal and abnormal gait. It has been applied to clinical condition assessment for a long time and has been formulated for treatment. The evaluation of strategy and treatment effect. Through the data collected by gait examination, the trajectory of joint activity and the force of joint in activity are calculated, which can be used to indirectly reflect the kinematic and dynamic state of the joint after TKA. Multi-bodydynamics (MBD) is the science of studying the motion law of multibody system. It includes several flexible and rigid objects, which are connected to a whole structure. The dynamic modeling of human body multibody dynamics can carry out the analysis of muscle activity and joint contact force in the gait cycle. It helps us understand the principle of muscle coordination and understanding the force of bone and soft tissue, and can be further developed on the basis of the model established. The study of prosthesis fretting analysis, prosthesis stress state analysis and polyethylene wear prediction in vivo. The joint force and joint motion predicted by the skeletal muscle multibody dynamics model can be output to the finite element software for subsequent analysis. The stress and strain obtained through this method are the weight of the study of the weight of artificial knee joint prosthesis. The multibody dynamic model takes into account the geometric shape of the bone, the design of the prosthesis, the muscles and ligaments around the joint, and the joint motion, the joint contact force, the muscle force and the ligament force are calculated at the same time. The above result parameters are input into the finite element software as the boundary strip to reflect the prosthesis in human The actual stress situation in the body. Combined with the human body multibody dynamic model and the modeling method of finite element analysis, the stress situation of the artificial knee joint can be well understood. It provides the theoretical basis for the improvement of the prosthesis design and the case analysis of clinical cases. The core of this study is divided into two parts: the first part is to take the three-dimensional gait. The analysis technique was used to quantify the changes of gait parameters after total knee replacement. The effect of TKA operation on human gait and limb function was observed. The second part was an attempt to establish the multi-body dynamics of the individual skeletal muscle through the bone geometric model of the patient, the three-dimensional data of the prosthesis and the gait analysis data. Model, in order to describe the joint activity more accurately, and predict the stress in the joint, make up for the defect that the intra-articular force can not be measured in vitro, it is an exploratory study. Method 1, three dimensional gait analysis after total knee replacement. Collection of three dimensional gait data of the ground surface reaction force and skin surface electromyography. The data collected include the relative position and direction of the body parts, the force of the foot and the ground, the time space relationship and the stage activity of the lower limb muscles. Both feet are completely stepped on the dynamometer for an effective data, each patient takes 5 to 8 effective data. The EMG signal and the analogue signal data of the dynamometer are collected synchronously through a unified working platform. Then the cortex real-time operation analysis software is used to define the various light points, and the three-dimensional space coordinates of each point are extracted, and the method of space geometry is used. The parameters of the gait were calculated, and the parameters were adjusted and optimized with the patient's morphological data collected before the test. The output results included space parameters, joint reaction force, joint motion angle and muscle activity signal. All parameters were compared between the side of the operation side.2, and the individualized multi body dynamic modeling of total knee arthroplasty was used for one case. A personalized skeletal muscle multibody dynamic model was established by the complete data of total knee arthroplasty. The data included the skeletal geometric model obtained by CT scan three-dimensional reconstruction, the 3D model of artificial joint prosthesis obtained by the three coordinate scanner, the 3D gait analysis data, and so on, based on the "FDK method" and the elastic base. The artificial knee joint prosthesis was integrated into the skeletal muscle model of the lower extremities, and the multibody dynamic model of the lower extremities after TKA was established to predict the flexion and extension activities of the knee joint in the gait cycle, the joint torque and the contact force of the tibial joint and patellar joint. Results 1, the gait analysis of the three dimensional gait after total knee replacement was used to study the gait. There was no significant difference between the space time parameters between the side and the healthy side (P0.05). The mean of the three joints in the hip, knee and ankle was less than the healthy side, but the difference was not statistically significant (P0.05). The range of flexion and extension of the hip joint was not changed, but the maximum flexion angle and maximum extension were not changed. The angles were smaller, and the difference was statistically significant (p=0.039, p0.001). The maximum external rotation angle of the hip joint increased, but the difference was not statistically significant (p=0.446), the maximum internal rotation angle and the rotation activity were decreased compared with the healthy side, and the difference was statistically significant (p0.001). The maximum flexion angle and flexion and extension of the knee joint and the healthy side were in the knee joint. There was no significant difference between the activity and the healthy side (p=0.185, p=0.194), but the maximum extension angle of the operation was more significant than that of the healthy Ce Zengda (p0.001). The difference was statistically significant (p=0.023, p=0.002), and the maximum angle of varus was not bilateral. The maximum internal rotation angle of the tibia decreased significantly on the side of the operation (p=0.025), but there was no significant difference between the maximum external rotation angle and the rotation range. The maximum flexion angle of the ankle joint, the maximum flexion angle and the flexion and extension activity were not significantly different between the two sides (p=0.286, p=0.780, p= 0.151), and the overturn movement of the lower joint existed between the two sides. The difference, the maximum angle of valgus and the maximum angle of varus were all larger than the healthy side (p=0.012, p0.001), and the turnover activity decreased significantly (p0.001). The signal of bilateral gluteus maximus did not change, the medial femoral muscle, the muscle of the cords were increased on the side of the operation, the gastrocnemius muscle was weakened on the side of operation (P0.05); the anterior tibial muscle weakened in the side of the operation and the peak signal The difference was statistically significant (p=0.036).2. The individualized multi body dynamic modeling of total knee arthroplasty was established. We successfully established a multi-body dynamic model of the individual skeletal muscle, and predicted the flexion and extension of the knee joint in the gait cycle, the joint torque and the contact force of the tibial joint and patellofemoral joint. The maximum flexion angle of the patellofemoral joint was not significantly different, and the maximum extension activity was lower than the healthy side. The three directions of the knee joint showed an increasing trend in the lateral knee joint. The peak torque of the flexion (extension) increased about 59.2%, the adductor (abduction) moment increased by about 18.6%, and the internal rotation (external rotation) increased the lowest, about 3.5%. lateral tibia. The contact force of the femoral joint and patellar joint was lower than the healthy side, in which the tibial joint decreased by about 5.8% and the patellar joint decreased by about 20.5%. 1. The three dimensional gait analysis based on infrared motion capture was used to analyze the gait state of the patients after total knee replacement. The results showed that TKA did not affect the spatial time parameters of the gait. In other words, 12 months after the operation, the walking function of the patient basically recovered 12 months after the operation, but the results of joint movement showed that there was a certain limit of extension of the knee joint on the side of the operation. The movement of the internal and external rotation of the knee joint and the internal and external rotation of the knee also changed, and then the kinematics of the hip joint and the ankle joint was secondary. The results of surface electromyography test were raised. The enhanced activity of the four head and rope muscles in the affected side suggests that the stability of the knee is weakened after TKA, and more muscles should be mobilized to maintain the dynamic balance of the joint. The artificial knee joint prosthesis was integrated into the skeletal muscle model of the lower extremities by the FDK method and the elastic base theory. The accurate bone modeling of the lower extremities was realized. The stability of the ligaments around the joint was considered. The knee joint movement, the tibial joint contact force and the patellar joint contact force after TKA were predicted. The results of the tibial and patellar joint were found. The maximum flexion angle of the joint was not significantly different, but the maximum extension activity was lower than the healthy side, and the three direction torque of the knee joint was higher than that of the healthy side, and the contact force of the tibial joint and patellar joint was lower than the healthy side. The model could be extended to any individual artificial knee replacement after the further optimization. It has good versatility in biomechanical research, and provides effective methods and methods for clinical outcome assessment, prosthesis design and prosthesis wear analysis.
【学位授予单位】：第三军医大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：R687.4

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