Ammann Elias, Hecker Andreas, Bachmann Elias, Snedeker Jess G, Fucentese Sandro F
Balgrist University Hospital, Zürich, Switzerland.
Orthop J Sports Med. 2022 May 11;10(5):23259671221096107. doi: 10.1177/23259671221096107. eCollection 2022 May.
Shortcomings to tibial-side fixation have been reported as causes of failure after anterior cruciate ligament reconstruction. Adjustable-loop suspensory devices have become popular; however, no comparison with hybrid fixation (ie, interference screw and cortical button) exists to our knowledge.
The purpose of this study was to compare the biomechanical properties of adjustable loop devices (ALDs) in full-tunnel and closed-socket configurations in relation to hybrid fixation. We hypothesized that primary stability of fixation by a tibial ALD will not be inferior to hybrid fixation.
Controlled laboratory study.
Tibial fixation of a quadrupled tendon graft was biomechanically investigated in a porcine tibia-bovine tendon model using 5 techniques (n = 6 specimens each). The tested constructs included hybrid fixation with a cortical fixation button and interference screw (group 1), single cortical fixation with the full-tunnel technique using an open-suture strand button (group 2) or an ALD (group 3), or closed-socket fixation using 2 different types of ALDs (groups 4 and 5). Each specimen was evaluated using a materials testing machine (1000 cycles from 50-250 N and pull to failure). Force at failure, cyclic displacement, stiffness, and ability to pretension the graft during insertion were compared among the groups.
No differences in ultimate load to failure were found between the ALD constructs (groups 3, 4, and 5) and hybrid fixation (group 1). Cyclic displacement was significantly higher in group 2 vs all other groups ( < .001); however, no difference was observed in groups 3, 4, and 5 as compared with group 1. The remaining tension on the construct after fixation was significantly higher in groups 3 and 4 vs groups 1, 2, and 5 ( < .02 for all comparisons), irrespective of whether a full-tunnel or closed-socket approach was used.
Tibial anterior cruciate ligament graft fixation with knotless ALDs achieved comparable results with hybrid fixation in the full-tunnel and closed-socket techniques. The retention of graft tension appears to be biomechanically more relevant than tunnel type.
The study findings emphasize the importance of the tension at which fixation is performed.
据报道，胫骨侧固定的缺点是前交叉韧带重建术后失败的原因。可调环悬吊装置已变得流行；然而，据我们所知，尚无与混合固定（即挤压螺钉和皮质纽扣）的比较。
本研究的目的是比较可调环装置（ALD）在全隧道和封闭套接配置下与混合固定相关的生物力学特性。我们假设胫骨ALD固定的初始稳定性不会低于混合固定。
对照实验室研究。
在猪胫骨 - 牛肌腱模型中，使用5种技术（每组n = 6个标本）对四倍肌腱移植物的胫骨固定进行生物力学研究。测试的结构包括使用皮质固定纽扣和挤压螺钉的混合固定（第1组）、使用开放缝线束纽扣的全隧道技术进行的单皮质固定（第2组）或ALD（第3组），或使用2种不同类型ALD的封闭套接固定（第4组和第5组）。使用材料试验机对每个标本进行评估（从50 - 250 N进行1000次循环并拉至失效）。比较各组之间的失效时力、循环位移、刚度以及在插入过程中对移植物进行预张紧的能力。
ALD结构（第3、4和5组）与混合固定（第1组）之间在最终失效载荷方面未发现差异。第2组的循环位移明显高于所有其他组（P <.001）；然而，与第1组相比，第3、4和5组未观察到差异。无论采用全隧道还是封闭套接方法，第3组和第4组固定后结构上的剩余张力均明显高于第1、2和5组（所有比较P <.02）。
在全隧道和封闭套接技术中，使用无结ALD进行胫骨前交叉韧带移植物固定与混合固定取得了可比的结果。移植物张力的保持在生物力学上似乎比隧道类型更相关。
研究结果强调了进行固定时张力的重要性。
