Three-dimensional dynamic behaviour of the human knee joint under impact loading
Three-dimensional dynamic behaviour of the human knee joint under impact loading
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DOI：
10.1016/s1350-4533(98)00010-1
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发表时间：
1998-06-01
影响因子：
2.2
通讯作者：
Hefzy, MS
中科院分区：
文献类型：
--
作者：
Abdel-Rahman, EM;Hefzy, MS
本研究的目的是确定人体膝关节的三维动态响应。由此建立了一个三维解剖动力学模型，该模型由两个接触的身体部分(股骨和胫骨)组成，在不同的韧带结构的约束下执行一般的三维动态运动。胫股关节处的每个关节表面都由一个单独的数学函数进行数学表示。将关节韧带建模为非线性弹性弹簧。用6个运动学参数描述六自由度关节运动，用这6个参数表示韧带的作用力。考虑外力脉冲载荷作用于胫骨，研究膝关节的响应。模型方程由非线性二阶常微分方程组和非线性代数约束条件组成。编写了约束方程以在整个运动过程中保持至少一个点接触；开发了模型的一个点接触版本和两个点接触版本。利用劳伦斯·利弗莫尔国家实验室开发的微分/代数系统求解器(DASSL)求解了这个微分-代数方程(DAE)系统。从而首次得到了表示该三维动力系统响应的解。由于系统固有的数值不稳定性和解决技术的局限性，早期确定系统反应的尝试没有成功，在测试的条件下，从模型预测中没有观察到胫骨内侧和外侧平台上的“股骨后滚”的证据。膝关节屈曲20°~66°时，胫骨外侧接触点后移，胫骨内侧接触点前移。在膝关节屈曲66度~90度的范围内，接触仅维持在内侧，胫骨接触点(内侧)继续向前移动。进一步发现，在给定的屈曲角度下，增加脉冲幅度和/或持续时间会导致胫骨-股骨接触力的大小减小。本研究的结果还表明，后十字韧带和内侧副韧带的前纤维是膝关节屈曲20度到90度范围内后强迫脉冲的主要限制因素，这解释了为什么大多数后十字韧带单独损伤和后十字韧带和内侧副韧带的复合损伤是由于后撞击屈膝造成的。(C)1998年爱思唯尔科学有限公司出版的IPEM。保留所有权利。
The objective of this study is to determine the three-dimensional dynamic response of the human knee joint. A three-dimensional anatomical dynamic model was thus developed and consists of two body segments in contact (the femur and tibia) executing a general three-dimensional dynamic motion within the constraints of the different ligamentous structures. Each of the articular surfaces at the tibio-femoral joint was represented mathematically by a separate mathematical function. The joint ligaments were modelled as nonlinear elastic springs. The six-degrees-of-freedom joint motions were characterized by using six kinematic parameters, and ligamentous forces were expressed in terms of these six parameters. Knee response was studied by considering sudden external forcing pulse loads applied to the tibia.Model equations consist of nonlinear second-order ordinary differential equations coupled with nonlinear algebraic constraint conditions. Constraint equations were written to maintain at least one-point contact throughout motion; one- and two-point contact versions of the model were developed. This Differential-Algebraic Equations (DAE) system was solved by employing a DAE solver: the Differential/Algebraic System Solver (DASSL) developed at Lawrence Livermore National Laboratory. A solution representing the response of this three-dimensional dynamic system was thus obtained for the first time. Earlier attempts to determine the system's response were unsuccessful owing to the inherent numerical instabilities in the system and the limitations of the solution techniques,Under the conditions tested, evidence of "femoral roll back" on both medial and lateral tibial plateaus was not observed from the model predictions. In the range of 20 degrees to 66 degrees of knee flexion, the lateral tibial contact point moved posteriorly while the medial tibial contact point moved anteriorly. In the range of 66 degrees to 90 degrees of knee flexion, contact was maintained only on the medial side and the tibial contact point (on the medial side) continued to move anteriorly. It was further found that increasing pulse amplitude and/or duration caused a decrease in the magnitude of the tibio-femoral contact force at a given flexion angle. These results suggest that increasing load level caused a decrease in joint stiffness.The results of this study also show that the anterior fibres of the posterior cruciate and the medial collateral ligaments are the primary restraints for a posterior forcing pulse in the range of 20 degrees to 90 degrees of knee flexion; this explains why most isolated posterior cruciate ligament injuries and combined injuries to the posterior cruciate and the medial collateral result from a posterior impact on a flexed knee. (C) 1998 IPEM Published by Elsevier Science Ltd. All rights reserved.