Tashiro Yasutaka, Irarrázaval Sebastián, Osaki Kanji, Iwamoto Yukihide, Fu Freddie H
Department of Orthopaedic Surgery, University of Pittsburgh, 3471 Fifth Avenue, Pittsburgh, PA, 15213, USA.
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
Knee Surg Sports Traumatol Arthrosc. 2017 Jan;25(1):129-137. doi: 10.1007/s00167-016-4191-1. Epub 2016 Jun 8.
To determine graft bending angle (GBA) during knee motion after anatomic anterior cruciate ligament (ACL) reconstruction and to clarify whether surgical techniques affect GBA. Our hypotheses were that the graft bending angle would be highest at knee extension and the difference of surgical techniques would affect the bending steepness.
Eight healthy volunteers with a mean age of 29.3 ± 3.0 years were recruited and 3D MRI knee models were created at three flexion angles (0°, 90° and 130°). Surgical simulation of the tunnel drilling was performed with anatomic tunnel position using each outside-in (OI), trans-portal (TP) and trans-tibial (TT) techniques on the identical cases. The models were matched to other knee positions and the GBA in 3D was measured using computational software. Double-bundle ACL reconstruction was analysed first, and single-bundle reconstruction was also analysed to evaluate its effect to reduce GBA. A repeated-measures ANOVA was used to compare GBA difference at three flexion angles, by three techniques or of three bundles.
GBA changed substantially with knee motion, and it was highest at full extension (p < 0.001) in each surgical technique. OI technique exhibited highest GBA for anteromedial bundle (94.3° ± 5.2°) at extension, followed by TP (83.1° ± 6.5°) and TT (70.0° ± 5.2°) techniques (p < 0.01). GBA for posterolateral bundle at extension were also high in OI (84.6° ± 7.4°), TP (83.0° ± 6.3°) and TT (77.2° ± 7.0°) techniques (n.s.). Single-bundle grafts did not decrease GBA compared with double-bundle grafts. In OI technique, a more proximal location of the femoral exit reduced GBA of each bundle at extension and 90° flexion.
A significant GBA change with knee motion and considerably steep bending at full extension, especially with OI and TP techniques, were simulated. Although single-bundle technique did not reduce GBA as seen in double-bundle technique, proximal location of femoral exits by OI technique, with tunnels kept in anatomic position, was effective in decreasing GBA at knee extension and flexion. For clinical relevance, high stress on graft and bone interface has been suggested by steep GBA at full extension after anatomic ACL reconstruction.
Therapeutic study (prospective comparative study), Level II.
确定解剖学前交叉韧带（ACL）重建术后膝关节运动过程中的移植物弯曲角度（GBA），并阐明手术技术是否会影响GBA。我们的假设是，移植物弯曲角度在膝关节伸展时最大，并且手术技术的差异会影响弯曲的陡度。
招募了8名平均年龄为29.3±3.0岁的健康志愿者，并在三个屈曲角度（0°、90°和130°）创建了3D MRI膝关节模型。在相同病例上，使用每种由外向内（OI）、经门（TP）和经胫骨（TT）技术，在解剖学隧道位置进行隧道钻孔的手术模拟。将模型与其他膝关节位置匹配，并使用计算软件测量3D中的GBA。首先分析双束ACL重建，也分析单束重建以评估其对降低GBA的效果。使用重复测量方差分析来比较三种屈曲角度、三种技术或三束之间的GBA差异。
GBA随膝关节运动而显著变化，并且在每种手术技术中，在完全伸展时最高（p<0.001）。在伸展时，OI技术显示前内侧束的GBA最高（94.3°±5.2°），其次是TP（83.1°±6.5°）和TT（70.0°±5.2°）技术（p<0.01）。在伸展时，OI（84.6°±7.4°）、TP（83.0°±6.3°）和TT（77.2°±7.0°）技术中后外侧束的GBA也较高（无显著性差异）。与双束移植物相比，单束移植物并未降低GBA。在OI技术中，股骨出口位置更靠近近端可降低伸展和90°屈曲时各束的GBA。
模拟了GBA随膝关节运动的显著变化以及在完全伸展时相当陡的弯曲，特别是在OI和TP技术中。尽管单束技术不像双束技术那样降低GBA，但在保持隧道处于解剖学位置的情况下，OI技术中股骨出口的近端位置可有效降低膝关节伸展和屈曲时的GBA。就临床相关性而言，解剖学ACL重建术后完全伸展时GBA陡峭提示移植物与骨界面存在高应力。
治疗性研究（前瞻性比较研究），II级。
