Jagodzinski M, Foerstemann T, Mall G, Krettek C, Bosch U, Paessler H H
Department of Trauma Surgery, Hanover Medical School, Carl-Neuberg-Str. 1, 30625 Hanover, Germany.
J Biomech. 2005 Jan;38(1):23-31. doi: 10.1016/j.jbiomech.2004.03.021.
Bone tunnel enlargement is a common phenomenon following reconstruction of the anterior cruciate ligament (ACL). Biomechanical and biological factors have been reported as potential causes of this problem. However, there is no analysis of forces between the graft and bone, as the graft changes direction at the bone tunnel entrance. The purpose of this study was to study these 'redirecting forces'. Magnetic resonance images of 10 patients with an ACL reconstruction (age: 26+/-6.8 years) were used to determine the angle between graft and drill holes. Vector analysis was used to calculate the direction and magnitude of the perpendicular component of the force between the bone tunnel and the graft at the entrance of the bone tunnel. Force components were projected into the radiographically important sagittal and coronal planes. Tension of ACL reconstructions was recorded during passive knee motion in 10 cadaveric knee experiments (age: 28.9+/-10.6 years) and the tension multiplied with the force component for each plane. Results are reported for the coronal and sagittal planes, respectively: For -10 degrees of extension, the percentages of graft tension were determined to be 17+/-7 (max: 26; min: 7%) and 26+/-9 (max: 39; min: 16%) for the tibia. They were 59+/-6 (max: 66; min: 48%) and 99+/-1 (max: 1.00; min: 99%) for the femur. Force components were 14.68+/-6.54 and 25.73+/-12.96 N for the tibial tunnel. For the femoral tunnel, they were 52.48+/-19.03 and 90.77+/-32.06 N. Percentages of graft tension and force components were significantly higher for the femoral tunnel compared with the tibial tunnel. Moreover, in the sagittal direction, force components for the femoral tunnel were significantly higher compared with the coronal plane (Wilcoxon test, p < 0.01). The differences in force components calculated in this study corresponds with the amount of tunnel enlargement in the radiographic planes in the literature providing evidence that biomechanical forces play a key role in postoperative tunnel expansion.
在前交叉韧带（ACL）重建术后，骨隧道扩大是一种常见现象。生物力学和生物学因素被报道为该问题的潜在原因。然而，由于移植物在骨隧道入口处改变方向，因此尚未对移植物与骨之间的力进行分析。本研究的目的是研究这些“转向力”。使用10例ACL重建患者（年龄：26±6.8岁）的磁共振图像来确定移植物与钻孔之间的角度。采用矢量分析来计算骨隧道入口处骨隧道与移植物之间力的垂直分量的方向和大小。力分量被投影到影像学上重要的矢状面和冠状面。在10个尸体膝关节实验（年龄：28.9±10.6岁）中记录了被动膝关节运动期间ACL重建的张力，并将张力与每个平面的力分量相乘。分别报告冠状面和矢状面的结果：对于伸展-10度，胫骨的移植物张力百分比分别确定为17±7（最大值：26；最小值：7%）和26±9（最大值：39；最小值：16%）。股骨的分别为59±6（最大值：66；最小值：48%）和99±1（最大值：1.00；最小值：99%）。胫骨隧道的力分量为14.68±6.54和25.73±12.96N。对于股骨隧道，分别为52.48±19.03和90.77±32.06N。与胫骨隧道相比，股骨隧道的移植物张力百分比和力分量明显更高。此外，在矢状方向上，股骨隧道的力分量与冠状面相比明显更高（Wilcoxon检验，p<0.01）。本研究中计算出的力分量差异与文献中影像学平面上的隧道扩大量相对应，这证明生物力学力在术后隧道扩张中起关键作用。
