基于TKA的人体下肢步态分析及仿真

发布时间：2018-09-11 08:23

【摘要】：膝关节作为人体最大且构造最复杂的关节,极易受到损伤。一般采用全膝置换术对晚期的膝关节疾病进行治疗。而关节置换术并非一劳永逸,很多患者术后都会出现关节失效等问题。目前,很多学者从运动生物力学的角度对骨关节炎发病机理、人工关节失效等问题进行了大量研究,但还未取得突破性成果。尤其,相对于欧美国家,我国的运动生物力学研究起步较晚,很多方面都不够完善。因此,针对国人的运动生物力学研究意义重大。有关运动生物力学的研究中,针对人体步态的研究开展最为广泛。正常人体步态具有周期性和稳定性,能够描述人体基本运动特征。本文采用三维运动捕捉、有限元分析、肌肉驱动模拟等先进的技术手段,对健康人体和接受TKA的患者进行了步态分析和仿真研究。本章所得结论揭示了健康人体下肢关节的运动规律和TKA对人体下肢关节运动的影响,对人工膝关节的设计以及TKA术后康复等都有指导作用。采用三维运动捕捉系统,对健康青年人和老年人在行走和慢跑时的时空参数和运动学参数进行研究。结果显示与青年人相比,老年人的速度和步长都较小,而步频相差不大。青年人和老年人之间存在的步态时空参数的年龄差异主要是老年人步长减小引起的。在行走和慢跑时,下肢关节的运动学参数也存在年龄差异。青年人和老年人下肢关节的运动范围差异与人体运动速度有关。采用三维运动捕捉系统和测力系统,对膝关节损伤的老年女性和健康老年女性在行走时的下肢关节运动学和动力学参数进行研究。结果显示,与健康受试者相比,TKA前患者的速度和步长较小,双支撑期明显变长。同时,患者更倾向于使用健康侧下肢膝关节,双侧髋关节和踝关节的运动会发生一定的代偿性变化。TKA后,患者的时空参数基本恢复到正常水平。而与健康受试者相比,患者下肢关节运动角度仍然存在较大差异,但关节运动力矩有较大改善。采用医学影像扫描和有限元分析技术,研究直立状态和脚跟着地相、单肢中立相、脚尖离地相四个瞬态时,人体膝关节的股骨软骨、胫骨软骨的接触应力分布情况,和人工膝关节的股骨假体、胫骨垫片和髌骨假体的接触应力分布情况。研究结果显示,人体膝关节中,股骨软骨最易产生磨损和病变,并且胫骨内侧软骨比外侧软骨易发生磨损。人工膝关节中,胫骨垫片和股骨假体上应力峰值较大,为容易产生关节失效的部位。采用Open Sim软件建立一名接受TKA患者的肌肉骨骼模型,分析四种步速下,患者手术侧和健康侧下肢主要肌肉的肌力和活动度的变化以及下肢主要肌肉分别引起的质心加速度。研究结果显示,随着步速下降,患者下肢各肌肉的肌力基本呈现逐渐减小的趋势。患者手术侧和健康侧肌肉力和肌肉活性基本一致,而双侧下肢肌肉对身体质心的作用完全相反。
[Abstract]:As the largest and most complicated joint of human body, knee joint is easy to be damaged. General use of total knee replacement for the treatment of late knee disease. Joint replacement is not once and for all, many patients will have joint failure and other problems. At present, many scholars have done a lot of research on the pathogenesis of osteoarthritis and artificial joint failure from the point of view of sports biomechanics, but no breakthrough results have been achieved. In particular, the study of sports biomechanics in China is relatively late compared with Europe and America, and many aspects are not perfect. Therefore, the study of sports biomechanics for Chinese is of great significance. In the research of sports biomechanics, the research on human gait is the most extensive. The gait of normal human body has periodicity and stability, and can describe the basic motion characteristics of human body. In this paper, gait analysis and simulation of healthy human body and patients receiving TKA were carried out by using advanced techniques such as 3D motion capture, finite element analysis and muscle drive simulation. The conclusions in this chapter reveal the movement law of lower extremity joint and the influence of TKA on lower extremity joint movement. It can guide the design of artificial knee joint and rehabilitation after TKA. The time and space parameters and kinematics parameters of walking and jogging of healthy young people and old people were studied by three dimensional motion capture system. The results showed that the speed and step length of the old people were smaller than that of the young people, but the step frequency was not different. The difference in gait space-time parameters between the young and the elderly is mainly caused by the decrease of the gait size. During walking and jogging, the kinematic parameters of lower extremity joints were also different in age. The range of lower extremity joint movement in young and old people is related to the movement speed of human body. The kinematic and dynamic parameters of lower extremity joints of elderly and healthy elderly women with knee joint injury were studied by means of three-dimensional motion capture system and force measuring system. The results showed that the speed and step length of the patients before TKA were smaller and the double support period was longer than that of the healthy subjects. At the same time, patients tend to use the healthy lower extremity knee joint, bilateral hip and ankle motion will have a certain compensatory change. TKA, the patient's space-time parameters are basically back to normal level. Compared with the healthy subjects, the lower extremity motion angle of the patients is still different, but the joint motion torque is improved greatly. Using medical imaging scanning and finite element analysis techniques, the contact stress distribution of femoral cartilage and tibial cartilage of human knee joint was studied under four transient conditions: vertical state and heel landing phase, neutral phase of single limb and apical phase. The contact stress distribution of femoral prosthesis, tibial pad and patellar prosthesis. The results show that femoral cartilage is the most prone to wear and lesion in human knee, and medial tibial cartilage is more prone to wear than lateral cartilage. In the artificial knee joint, the peak stress of tibial gasket and femur prosthesis is high, which is prone to joint failure. A musculoskeletal model of a patient receiving TKA was established by using Open Sim software. The changes of muscle strength and movement of the main muscles of the lower extremities and the acceleration of the center of mass caused by the main muscles of the lower extremities were analyzed under four walking speeds. The results showed that the muscle strength of lower extremity muscles decreased gradually with the decrease of walking speed. The muscle strength and muscle activity of the surgical side and the healthy side were basically the same, but the effect of bilateral lower extremity muscles on the body centroid was completely opposite.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R687.4;R318.1

【参考文献】