Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine, S1-w16 Chu-ou-ku, Sapporo, 060-8543, Japan.
Knee Surg Sports Traumatol Arthrosc. 2012 Jan;20(1):127-34. doi: 10.1007/s00167-011-1576-z. Epub 2011 Jun 22.
Normal anterior cruciate ligament (ACL) can be divided into three fiber bundles-i.e., anteromedial (AM), intermediate (IM), and posterolateral (PL) bundles. However, their arrangement and attachment areas had remained unclear. The purpose of this study was to clarify the arrangement of these three ACL fiber bundles and their attachment sites, and to provide information on the tunnel placement in anatomical triple bundle ACL reconstruction.
Seven non-embalmed human frozen knees were used. ACL fibers were bluntly divided into three bundles. A different-colored thread was wound around each fiber bundle in a spiral. Macroscopical investigation was performed to clarify the arrangement of three ACL bundles. Each fiber bundle was carefully detached from the femur and tibia, and then the distribution of attachment sites of each fiber bundle was observed.
In knee extension, all bundles consisting of AM, IM and PL bundles ran parallel to each other in the lateral view from the medial side. The AM bundle overlapped with the IM bundle, whereas the PL bundle ran parallel to them on the distal aspects. As the knee flexion increased, the bundles became twisted around each other. On the tibial side, the attachment areas of three fiber bundles formed a triangular shape showing arrangements of AM, IM and PL bundles on the anteromedial, anterolateral and posterior aspects, respectively. On the femoral side, the PL bundle was attached on the distal-posterior areas; the IM bundle was attached distal-anterior to the AM bundle. They were arranged in a triangular shape on the tibia side as well.
This study clarified the arrangement of three fiber bundles of ACL and detailed geographical locations of their attachment sites. The detailed anatomic description of the natural ACL attachment might suggest to surgeons where to make tunnels during anatomical double/triple bundle ACL reconstruction.
正常前交叉韧带（ACL）可分为三束纤维——即前内束（AM）、中间束（IM）和后外束（PL）。然而，它们的排列和附着区域仍不清楚。本研究旨在阐明这三束 ACL 纤维的排列及其附着部位，并为解剖性三束 ACL 重建中隧道的放置提供信息。
使用 7 个未经防腐处理的人冷冻膝关节。ACL 纤维被钝性地分为三束。每根纤维束都用不同颜色的线螺旋缠绕。进行宏观研究以阐明三束 ACL 的排列。小心地将每个纤维束从股骨和胫骨上分离下来，然后观察每个纤维束的附着部位分布。
在膝关节伸直时，从内侧看，所有由 AM、IM 和 PL 束组成的束在外侧呈平行排列。AM 束与 IM 束重叠，而 PL 束在远端与它们平行。随着膝关节屈曲度的增加，束相互扭曲。在胫骨侧，三束纤维的附着区形成一个三角形，分别显示 AM、IM 和 PL 束在前内、前外和后方面的排列。在股骨侧，PL 束附着于远端后区；IM 束附着于 AM 束的远端前区。它们在胫骨侧也呈三角形排列。
本研究阐明了 ACL 三束纤维的排列及其附着部位的详细地理位置。对自然 ACL 附着的详细解剖描述可能会提示外科医生在进行解剖性双/三束 ACL 重建时在哪里制作隧道。
