Amiri Shahram, Cooke T Derek V, Wyss Urs P
Department of Orthopedic Surgery, University of British Columbia, Vancouver, BC, Canada.
Knee. 2011 Jan;18(1):34-41. doi: 10.1016/j.knee.2010.01.003. Epub 2010 Jan 29.
Measurements of elongations of the cruciate ligaments have been used to study the behaviors of these ligaments in-vitro and in-vivo, mostly based on simplified two-bundle models of the cruciates. The complex fiber anatomy of the cruciates may suggest a complex deformation behavior across the continuum of their substance that cannot be captured by only two measurement points. In this study, a new methodology was introduced to include more detailed fiber anatomy and to take into consideration the wrapping of the PCL around the intercondylar notch of the femur in deep flexion. The method was used in comparison to the conventional two-bundle models on three sample cadaver knees that underwent a passive flexion up to 150°. The elongation ratios of the bundles were measured as the ratio of change in the length of the bundles over their lengths at 0° flexion. The multiple-bundle models showed ranges of variations across the attachment sites of the cruciates which at all flexion angles were significantly larger than those observed from the conventional two-bundle models. When expressed in percentages, at 150° flexion the ranges of variations in the elongation ratio of the bundles were 32.7%±31.9% and 34%±8.6% for the ACL and PCL, respectively. Results of this study showed that important variations of elongation across the body of the cruciates can be obscured to the conventional two-bundle model of the cruciates, and therefore a more detailed bundle configuration is suggested for the purpose of studying elongation behaviors of these ligaments.
十字韧带伸长的测量已被用于研究这些韧带在体外和体内的行为，主要基于十字韧带简化的双束模型。十字韧带复杂的纤维解剖结构可能表明，其整个实体存在复杂的变形行为，仅通过两个测量点无法捕捉到这种行为。在本研究中，引入了一种新方法，以纳入更详细的纤维解剖结构，并考虑到在深度屈曲时后交叉韧带（PCL）围绕股骨髁间切迹的缠绕情况。该方法与传统双束模型相比，应用于三个样本尸体膝关节，这些膝关节被动屈曲至150°。束的伸长率以束在0°屈曲时的长度变化与长度的比值来测量。多束模型显示，在十字韧带的附着部位，所有屈曲角度下的变化范围均显著大于传统双束模型观察到的范围。以百分比表示时，在150°屈曲时，前交叉韧带（ACL）和PCL束伸长率的变化范围分别为32.7%±31.9%和34%±8.6%。本研究结果表明，十字韧带整个实体伸长的重要变化可能会被十字韧带的传统双束模型所掩盖，因此，为了研究这些韧带的伸长行为，建议采用更详细的束配置。
