Nhan Derek T, Belkoff Stephen M, Singh Prerna, Sullivan Brian T, Klyce Walter, Lee R Jay
Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Orthop J Sports Med. 2021 Apr 6;9(4):2325967121996487. doi: 10.1177/2325967121996487. eCollection 2021 Apr.
Injured anterior cruciate ligament (ACL) tissue retains proprioceptive nerve fibers, vascularity, and biomechanical properties. For these reasons, remnant ACL tissue is often preserved during the treatment of ACL injuries.
To assess through a cadaveric model whether reorienting and retensioning the residual ACL via an osteotomy improves knee stability after partial ACL tear, with substantial remnant tissue and intact femoral and tibial attachments.
Controlled laboratory study.
In 8 adult cadaveric knees, we measured anterior tibial translation and rotational laxity at 30° and 90° of flexion with the ACL in its native state and in 3 conditions: partial tear, retensioned, and ACL-deficient. The partial-tear state consisted of a sectioned anteromedial ACL bundle.
In the native state, the translation was 10 ± 2.7 mm (mean ± SD) at 30° of flexion and 8.4 ± 3.6 mm at 90° of flexion. Anterior translation of the knees in the partial-tear state (14 ± 2.7 mm at 30° and 12 ± 2.7 mm at 90°) was significantly greater than baseline ( < .001 for both). Translation in the ACL-retensioned state (9.2 ± 1.7 mm at 30° and 7.2 ± 2.1 mm at 90°) was significantly less than in the ACL-deficient state ( .001 for both), and translation was not significantly different from that of the intact state. For ACL-deficient knees, translation (20 ± 4.3 mm at 30° and 16 ± 4.4 mm at 90°) was significantly greater than all other states ( < .001 for all). Although rotational testing demonstrated the least laxity at 30° and 90° of flexion in the retensioned and intact states and the most laxity in the ACL-deficient state, rotation was not significantly different among any of the experimental states.
In a cadaveric model of an incomplete ACL tear, a reorienting and retensioning core osteotomy at the tibial insertion of the remnant ACL improved anteroposterior translation of the knee without compromising its rotational laxity.
The findings of this study support the concept of ACL tissue reorienting and retensioning in the treatment of ACL laxity as an area for future investigation.
前交叉韧带（ACL）损伤组织保留了本体感觉神经纤维、血管和生物力学特性。基于这些原因，在ACL损伤治疗过程中，常常保留ACL残余组织。
通过尸体模型评估，对于部分ACL撕裂且有大量残余组织以及股骨和胫骨附着点完整的情况，经截骨术重新定向并重新张紧残余ACL是否能改善膝关节稳定性。
对照实验室研究。
在8个成年尸体膝关节中，我们测量了ACL处于自然状态以及三种情况下膝关节在30°和90°屈曲时的胫骨前移和旋转松弛度，这三种情况分别为：部分撕裂、重新张紧以及ACL缺失。部分撕裂状态由切断的前内侧ACL束组成。
在自然状态下，30°屈曲时的前移为10±2.7毫米（平均值±标准差），90°屈曲时为8.4±3.6毫米。部分撕裂状态下膝关节的前向移位（30°时为14±2.7毫米，90°时为12±2.7毫米）显著大于基线水平（两者均P<.001）。ACL重新张紧状态下的移位（30°时为9.2±1.7毫米，90°时为7.2±2.1毫米）显著小于ACL缺失状态（两者均P<.001），且与完整状态下的移位无显著差异。对于ACL缺失的膝关节，移位（30°时为20±4.3毫米，90°时为16±4.4毫米）显著大于所有其他状态（所有均P<.001）。尽管旋转测试表明，在重新张紧和完整状态下，30°和90°屈曲时的松弛度最小，而在ACL缺失状态下最大，但在任何实验状态之间，旋转差异均无统计学意义。
在不完全ACL撕裂的尸体模型中，在残余ACL的胫骨附着点处进行重新定向和重新张紧的核心截骨术可改善膝关节的前后移位，而不会影响其旋转松弛度。
本研究结果支持在治疗ACL松弛时对ACL组织进行重新定向和重新张紧这一概念，作为未来研究的一个领域。
