TY - JOUR
T1 - A global verification study of a quasi-static knee model with multi-bundle ligaments
AU - Mommersteeg, T.J.A.
AU - Huiskes, H.W.J.
AU - Blankevoort, L.
AU - Kooloos, J.G.M.
AU - Kauer, J.M.G.
AU - Maathuis, P.G.M.
PY - 1996
Y1 - 1996
N2 - The ligaments of the knee consist of fiber bundles with variable orientations, lengths and mechanical properties. In concept, however, these structures were too often seen as homogeneous structures, which are either stretched or slack during knee motions. In previous studies, the authors proposed a new structural concept of the ligaments of the knee. In this concept, the ligaments were considered as multi-bundle structures, with nonuniform mechanical properties and zero force lengths. The purpose of the present study was to verify this new concept. For this purpose, laxity characteristics of a human knee joint were compared as measured in an experiment and predicted in a model simulation study. In the experiment, the varus-valgus and anterior-posterior laxities of a knee-joint specimen containing the ligaments and the articular surfaces only, were determined. From this knee-joint, geometric and mechanical parameters were derived to supply the parameters for a three-dimensional (3D) quasi-static knee-joint model. These parameters included (i) the 3D insertion points of bundles, defined in the four major knee ligaments, (ii) the mechanical properties of these ligament, as functions of their relative insertion orientations and (iii) 3D representations of the articular surfaces. With this model the experiments were simulated. If knee-model predictions and experimental results agree, then the multi-bundle ligament models are validated, at least with respect to their functional role in anterior-posterior and varus-valgus loading of the joint. The model described the laxity characteristics in AP-translation and VV-rotation of the cadaveric knee-joint specimen reasonably well. Both display the same patterns of laxity changes during knee flexion. Only if a varus moment of 8 Nm was applied and if the tibia was posteriorly loaded, did the model predict a slightly higher laxity than that measured experimentally. From the model-experiment comparisons it was concluded that the proposed structural representations of the ligaments and their mechanical properly distributions seem to be valid for studying the anterior-posterior and varus-valgus laxity characteristics of the human knee-joint
AB - The ligaments of the knee consist of fiber bundles with variable orientations, lengths and mechanical properties. In concept, however, these structures were too often seen as homogeneous structures, which are either stretched or slack during knee motions. In previous studies, the authors proposed a new structural concept of the ligaments of the knee. In this concept, the ligaments were considered as multi-bundle structures, with nonuniform mechanical properties and zero force lengths. The purpose of the present study was to verify this new concept. For this purpose, laxity characteristics of a human knee joint were compared as measured in an experiment and predicted in a model simulation study. In the experiment, the varus-valgus and anterior-posterior laxities of a knee-joint specimen containing the ligaments and the articular surfaces only, were determined. From this knee-joint, geometric and mechanical parameters were derived to supply the parameters for a three-dimensional (3D) quasi-static knee-joint model. These parameters included (i) the 3D insertion points of bundles, defined in the four major knee ligaments, (ii) the mechanical properties of these ligament, as functions of their relative insertion orientations and (iii) 3D representations of the articular surfaces. With this model the experiments were simulated. If knee-model predictions and experimental results agree, then the multi-bundle ligament models are validated, at least with respect to their functional role in anterior-posterior and varus-valgus loading of the joint. The model described the laxity characteristics in AP-translation and VV-rotation of the cadaveric knee-joint specimen reasonably well. Both display the same patterns of laxity changes during knee flexion. Only if a varus moment of 8 Nm was applied and if the tibia was posteriorly loaded, did the model predict a slightly higher laxity than that measured experimentally. From the model-experiment comparisons it was concluded that the proposed structural representations of the ligaments and their mechanical properly distributions seem to be valid for studying the anterior-posterior and varus-valgus laxity characteristics of the human knee-joint
U2 - 10.1016/0021-9290(96)00076-0
DO - 10.1016/0021-9290(96)00076-0
M3 - Article
SN - 0021-9290
VL - 29
SP - 1659
EP - 1664
JO - Journal of Biomechanics
JF - Journal of Biomechanics
IS - 12
ER -