Blankevoort L, Huiskes R
Biomechanis Section, University of Nijmegen, The Netherlands.
J Biomech Eng. 1991 Aug;113(3):263-9. doi: 10.1115/1.2894883.
In mathematical knee-joint models, the ligaments are usually represented by straight-line elements, connecting the insertions of the femur and tibia. Such a model may not be valid if a ligament is bent in its course over bony-surfaces, particularly not if the resulting redirection of the ligament force has a considerable effect on the laxity or motion characteristics of the knee-joint model. In the present study, a model for wrapping of a ligament around bone was incorporated in a three-dimensional mathematical model of the human knee. The bony edge was described by a curved line on which the contact point of the line element representing a ligament bundle was located. Frictionless contact between the ligament bundle and the bone was assumed. This model was applied to the medial collateral ligament (MCL) interacting with the bony edge of the tibia. It was found that, in comparison with the original model without bony interactions, the bony edge redirected the ligament force of the MCL in such a way that it counterbalanced valgus moments on the tibia more effectively. The effect of the bony interaction with the MCL on the internal-external rotation laxity, however, was negligible.
在数学膝关节模型中，韧带通常由连接股骨和胫骨附着点的直线单元表示。如果韧带在其跨越骨表面的行程中发生弯曲，这样的模型可能无效，尤其是当韧带力的由此产生的重新定向对膝关节模型的松弛度或运动特性有相当大的影响时。在本研究中，一个韧带围绕骨骼缠绕的模型被纳入人体膝关节的三维数学模型中。骨边缘由一条曲线描述，代表韧带束的线单元的接触点位于该曲线上。假定韧带束与骨骼之间为无摩擦接触。该模型应用于与胫骨骨边缘相互作用的内侧副韧带（MCL）。结果发现，与没有骨相互作用的原始模型相比，骨边缘以这样一种方式重新定向MCL的韧带力，即它能更有效地平衡胫骨上的外翻力矩。然而，骨与MCL的相互作用对内外旋转松弛度的影响可以忽略不计。
