Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Arthroscopy. 2014 Jul;30(7):841-8. doi: 10.1016/j.arthro.2014.03.004. Epub 2014 May 2.
If the aperture of the oval-shaped femoral tunnel on the lateral cortex becomes bigger than half the size of the cortical button, the risk of fixation failure increases. This study investigated the effect of the location of the entry point and diameter of the femoral tunnel on the length of the major axis of the tunnel aperture in anterior cruciate ligament (ACL) reconstruction using an outside-in technique.
Simulation of femoral tunnel drilling was performed on computed tomography (CT)-based 3-dimensional (3D) bone models obtained from 40 participants. The tunnel connected the center of the ACL footprint and various points on the lateral femoral surface. The diameter of the tunnel was set at 4.2 mm, 5.2 mm, or 6 mm, depending on the commercially available outside-in surgical systems (Arthrex, Naples, FL and Smith & Nephew, Andover, MA). The length of the major axis of the oval-shaped aperture on the lateral femoral surface was measured.
When the tunnel was introduced at 2 cm from the lateral epicondyle in a 45° anteroproximal direction, the major axis was lengthened to 130.7% ± 9.0% (P < .001) of the tunnel diameter, and it was more than 6.5 mm in 65% of participants in whom a 5.2-mm-diameter tunnel was drilled. When the entry point was 3 cm from the lateral epicondyle, 60% of participants had an oval-shaped aperture with a major axis of more than 6.5 mm, even though the diameter of the tunnel was only 4.2 mm.
The risk of fixation failure of a cortical button increases if the entry point for drilling is 2 cm or further from the lateral epicondyle and the tunnel diameter is more than 5 mm.
This study indicates the potential risk of cortical button fixation failure caused by an oval tunnel aperture on the lateral femoral surface in ACL reconstruction using the outside-in technique.
如果外侧皮质上椭圆形股骨隧道的孔径增大到皮质纽扣尺寸的一半以上，则固定失败的风险增加。本研究通过关节镜下单束重建前交叉韧带（ACL）的外侧入路技术，探讨了进钉点位置和股骨隧道直径对隧道开口长轴的影响。
对 40 名参与者的基于 CT 的三维（3D）骨模型进行了股骨隧道模拟钻孔。隧道连接 ACL 附着点中心和外侧股骨表面的各个点。根据市售的关节镜下单束重建 ACL 的外侧入路技术（Arthrex，Naples，FL 和 Smith & Nephew，Andover，MA），隧道直径设定为 4.2mm、5.2mm 或 6mm。测量外侧股骨表面椭圆形开口的长轴长度。
当隧道以 45°前向近端从外上髁进钉 2cm 时，长轴延长至隧道直径的 130.7%±9.0%（P<.001），其中 65%的参与者在使用 5.2mm 直径的隧道时，长轴超过 6.5mm。当进钉点位于外上髁 3cm 时，即使隧道直径仅为 4.2mm，60%的参与者的椭圆形开口长轴也超过 6.5mm。
如果钻孔的进钉点距离外上髁 2cm 或更远，且隧道直径大于 5mm，则皮质纽扣固定失败的风险增加。
本研究表明，外侧入路技术关节镜下单束重建 ACL 时，股骨隧道外侧表面椭圆形隧道开口可能导致皮质纽扣固定失败。
