Dynamic analysis of the knee after total joint arthroplasty by hardware-in-the-loop simulation

全关节置换术后膝关节的半实物仿真动态分析

• 批准号: 235922259
• 负责人: Professor Dr. Rainer Bader
• 金额: --
• 依托单位: Lehrstuhl für Technische Mechanik/Dynamik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/235922259?language=en
• 关键词: Dynamic; analysis; knee; after; total

Despite sophisticated implant designs every fourth patient remains dissatisfied with the clinical and functional outcome after total knee arthroplasty. Discontentment as well as occurring complications usually result into restricted mobility of the patient and subsequent implant failure requiring revision surgery. However, it has not been possible so far to investigate failure mechanisms as well as kinematics and load situation of knee endoprostheses under physiological circumstances by use of established testing methods.The objective of this proposal is to develop a novel robot-based test system in order to investigate knee endoprostheses with respect to joint kinematics and dynamic stability behavior with high accuracy. The approach is taking into account adjacent ligaments and capsular structures, and allows for evaluation of implant components and surgical techniques. Frequent and potential failure causes are revealed by comparing motion patterns of native knee joints and after total knee arthroplasty.Relevant ligaments, capsular and muscular structures have been insufficiently addressed in experimental setups under reproducible conditions so far. Hence, our approach is to implement the adjacent soft tissue structures into a biomechanical model. The real implant components are moved and loaded by an industrial robot serving as actuator system. At the same time, the biomechanical model communicates with the robot within a Hardware-in-the-Loop (HiL) control loop exchanging kinematic and force data in real time. As a result, the movement and loading of knee endoprostheses are generated taking into consideration soft tissue structures and real contact conditions in a reproducible and unique manner.In preliminary work we have already successfully implemented the HiL environment for total hip replacements. However, an optimised approach is required for investigating knee endoprostheses due to the complexity of the knee joint. Hence, the native kinematics as well as the mechanical properties of surrounding ligaments and capsular structures have to be identified by testing cadaveric knees using the robot. Based on the gained data the biomechanical model is built-up. Furthermore, the sensory and control system of the physical setup is adapted to the knee joint followed by the configuration and the validation of the HiL environment. Based on HiL simulations variations of implant designs, implant positioning and surgical techniques are considered and their impact on joint kinematics and load situation will be evaluated. Moreover, finite element analyses are conducted using the results of the HiL simulations as boundary conditions in order to determine stresses, strains and contact pressure in the artificial knee joint.

尽管有复杂的植入物设计，但每四名患者中就有一名对全膝关节置换术后的临床和功能结果不满意。不满意以及发生的并发症通常会导致患者活动受限，随后植入物失效，需要进行翻修手术。然而，迄今为止，它还没有可能调查失败的机制，以及运动学和负载情况下的膝关节endoprostheses在生理环境下，通过使用已建立的测试methods.This建议的目的是开发一种新的机器人为基础的测试系统，以调查膝关节endoprostheses与关节运动学和动态稳定性行为，具有高精度。该入路考虑了邻近韧带和关节囊结构，并允许对植入物组件和手术技术进行评价。通过比较自体膝关节和全膝关节置换术后的运动模式，揭示了常见的和潜在的失败原因。到目前为止，在可重复条件下的实验装置中，相关的韧带、关节囊和肌肉结构还没有得到充分的解决。因此，我们的方法是将相邻的软组织结构实现为生物力学模型。真实的植入物组件由用作致动器系统的工业机器人移动和装载。同时，生物力学模型与硬件在环（HiL）控制回路内的机器人通信，真实的交换运动学和力数据。因此，膝关节内假体的运动和载荷是在考虑软组织结构和真实的接触条件的情况下以可重复和独特的方式产生的。在初步工作中，我们已经成功地实现了全髋关节置换的HiL环境。然而，由于膝关节的复杂性，研究膝关节内假体需要一种优化的方法。因此，本地运动学以及周围韧带和关节囊结构的机械性能必须通过使用机器人测试尸体膝关节来确定。根据获得的数据建立了生物力学模型。此外，物理设置的感觉和控制系统适用于膝关节，然后是HiL环境的配置和验证。基于HiL模拟，考虑了植入物设计、植入物定位和手术技术的变化，并将评价其对关节运动学和载荷情况的影响。此外，有限元分析进行使用HiL模拟的结果作为边界条件，以确定应力，应变和接触压力的人工膝关节。