Scott and White Memorial Hospital, Temple, Texas 76508, USA.
Arthroscopy. 2012 Oct;28(10):1481-9. doi: 10.1016/j.arthro.2012.03.019. Epub 2012 Jul 15.
To evaluate knee stability after anterior cruciate ligament (ACL) reconstruction using 2 modern clinically relevant single-bundle constructs.
Two arthroscopic ACL reconstructions were performed on 6 fresh-frozen human cadaveric knees using bone-patellar tendon-bone autografts. The tibial tunnel was centered in the anatomic tibial footprint. The femoral tunnel was reamed through the anteromedial (AM) portal and centered alternately in either the AM portion of the femoral footprint (center-AM) or the center of the femoral footprint (center-center). Two external loading conditions were applied: (1) a 134-N anterior tibial load and (2) a 10-Nm valgus load combined with a 5-Nm internal tibial torque. Resulting kinematics were determined under 4 conditions: (1) ACL intact, (2) ACL deficient, (3) center-AM reconstruction, and (4) center-center reconstruction.
In response to anterior tibial loading, anterior translation was similar in the ACL-intact knee and the 2 reconstructions at 0° to 60° of flexion but was greater in the reconstructed specimens at 90°. In response to the complex rotatory load, internal tibial rotation (ITR) at 30° of flexion was slightly greater in center-AM knees compared with ACL-intact knees (11.0° ± 0.6° v 10.5° ± 0.6°, P = .03). At other angles tested, ITR in both reconstructions was similar to the ACL-intact knee (P > .05). When we compared the 2 reconstruction alternatives, however, center-center knees exhibited greater resistance to ITR at all angles (P < .05).
Anatomic single-bundle ACL reconstruction performed with the femoral tunnel placed through the AM portal restores translational and rotational knee stability to an extent that closely approximates the ACL-intact condition. When compared with the AM femoral tunnel position, a femoral tunnel positioned in the anatomic center of the femoral origin of the ACL may further improve rotatory stability without sacrificing anterior stability.
This study provides additional biomechanical evidence in support of anatomic single-bundle ACL reconstruction with tunnels positioned in the center of the femoral and tibial footprints.
使用 2 种现代临床相关的单束重建结构评估前交叉韧带（ACL）重建后的膝关节稳定性。
对 6 个新鲜冷冻的人体尸体膝关节进行了 2 次关节镜 ACL 重建，使用骨-髌腱-骨自体移植物。胫骨隧道位于解剖胫骨足迹的中心。股骨隧道通过前内侧（AM）入路扩孔，并交替位于股骨足迹的 AM 部分（中心-AM）或股骨足迹的中心（中心-中心）。施加了 2 种外部加载条件：（1）134N 的胫骨前负荷和（2）10N·m 的外翻负荷加 5N·m 的胫骨内扭矩。在 4 种情况下确定了由此产生的运动学：（1）ACL 完整，（2）ACL 缺失，（3）中心-AM 重建和（4）中心-中心重建。
在前胫骨加载下，在 0°至 60°屈曲时，ACL 完整的膝关节和 2 种重建膝关节的前向平移相似，但在 90°时重建标本的前向平移更大。在复杂的旋转负荷下，在 30°屈曲时，中心-AM 膝关节的胫骨内旋转（ITR）略大于 ACL 完整膝关节（11.0°±0.6°比 10.5°±0.6°，P=.03）。在测试的其他角度，两种重建方法的 ITR 均与 ACL 完整膝关节相似（P>.05）。然而，当我们比较两种重建方案时，中心-中心膝关节在所有角度都表现出对 ITR 的更大抵抗力（P<.05）。
通过 AM 入路放置股骨隧道进行解剖学单束 ACL 重建，在某种程度上恢复了膝关节的平移和旋转稳定性，接近 ACL 完整的状态。与 AM 股骨隧道位置相比，将股骨隧道放置在 ACL 股骨起点的解剖中心可能会进一步提高旋转稳定性，而不会牺牲前向稳定性。
这项研究提供了额外的生物力学证据，支持在股骨和胫骨足迹的中心位置放置隧道的解剖学单束 ACL 重建。
