Abstract：
The way in which force increases in the anterolateral tissues and the lateral extra-articular tenodesis (LET) tissue to resist internal rotation (IR) of the tibia after anterior cruciate ligament (ACL) reconstruction in isolation and after LET augmentation, respectively, is not well understood.
(1) To compare in a cadaveric model how force increases (ie, engages) in the anterolateral tissues with IR of the tibia after isolated ACL reconstruction and in the LET tissue after augmentation of the ACL reconstruction with LET and (2) to determine whether IR of the tibia is related to engagement of the LET tissue.
Controlled laboratory study.
IR moments were applied to 9 human cadaveric knees at 0°, 30°, 60°, and 90° of flexion using a robotic manipulator. Each knee was tested in 2 states: (1) after isolated ACL reconstruction with intact anterolateral tissues and (2) after LET was performed using a modified Lemaire technique with the LET tissue fixed at 60° of flexion under 44 N of tension. Resultant forces carried by the anterolateral tissues and the LET tissue were determined via superposition. The way force increased in these tissues was characterized via parameters of tissue engagement, namely in situ slack, in situ stiffness, and tissue force at peak applied IR moment, and then compared (α < .05). IR was related to parameters of engagement of the LET tissue via simple linear regression (α < .05).
The LET tissue exhibited less in situ slack than the anterolateral tissues at 30°, 60°, and 90° of flexion (P≤ .04) and greater in situ stiffness at 30° and 90° of flexion (P≤ .043). The LET tissue carried greater force at the peak applied IR moment at 0° and 30° of flexion (P≤ .01). IR was related to the in situ slack of the LET tissue (R2≥ 0.88; P≤ .0003).
LET increased restraint to IR of the tibia compared with the anterolateral tissue, particularly at 30°, 60°, and 90° of flexion. IR of the tibia was positively associated with in situ slack of the LET tissue.
Fixing the LET at 60° of flexion still provided IR restraint in the more functionally relevant flexion angle of 30°. Surgeons should pay close attention to the angle of internal and/or external tibial rotation when fixing the LET tissue intraoperatively because this surgical parameter is related to in situ slack of the LET tissue and, therefore, the amount of IR of the tibia.
(1) To compare in a cadaveric model how force increases (ie, engages) in the anterolateral tissues with IR of the tibia after isolated ACL reconstruction and in the LET tissue after augmentation of the ACL reconstruction with LET and (2) to determine whether IR of the tibia is related to engagement of the LET tissue.
Controlled laboratory study.
IR moments were applied to 9 human cadaveric knees at 0°, 30°, 60°, and 90° of flexion using a robotic manipulator. Each knee was tested in 2 states: (1) after isolated ACL reconstruction with intact anterolateral tissues and (2) after LET was performed using a modified Lemaire technique with the LET tissue fixed at 60° of flexion under 44 N of tension. Resultant forces carried by the anterolateral tissues and the LET tissue were determined via superposition. The way force increased in these tissues was characterized via parameters of tissue engagement, namely in situ slack, in situ stiffness, and tissue force at peak applied IR moment, and then compared (α < .05). IR was related to parameters of engagement of the LET tissue via simple linear regression (α < .05).
The LET tissue exhibited less in situ slack than the anterolateral tissues at 30°, 60°, and 90° of flexion (P≤ .04) and greater in situ stiffness at 30° and 90° of flexion (P≤ .043). The LET tissue carried greater force at the peak applied IR moment at 0° and 30° of flexion (P≤ .01). IR was related to the in situ slack of the LET tissue (R2≥ 0.88; P≤ .0003).
LET increased restraint to IR of the tibia compared with the anterolateral tissue, particularly at 30°, 60°, and 90° of flexion. IR of the tibia was positively associated with in situ slack of the LET tissue.
Fixing the LET at 60° of flexion still provided IR restraint in the more functionally relevant flexion angle of 30°. Surgeons should pay close attention to the angle of internal and/or external tibial rotation when fixing the LET tissue intraoperatively because this surgical parameter is related to in situ slack of the LET tissue and, therefore, the amount of IR of the tibia.
摘要：
■前交叉韧带（ACL）重建后和LET增强后，前外侧组织和外侧关节外肌腱固定术（LET）组织中的力增加以抵抗胫骨内部旋转（IR）的方式，分别,不是很了解。
■（1）在尸体模型中比较力如何增加（即，接合）在分离的ACL重建后胫骨IR的前外侧组织中，以及在用LET增强ACL重建后的LET组织中，以及（2）确定胫骨IR是否与LET组织的接合有关。
■对照实验室研究。
■在0°处对9个人尸体膝盖施加IR矩，30°,60°,使用机器人操纵器弯曲90°。在2种状态下对每个膝盖进行了测试：（1）在完整的前外侧组织进行孤立的ACL重建后，以及（2）在使用改良的Lemaire技术进行LET后，LET组织在44N的张力下以弯曲60°固定。通过叠加确定前外侧组织和LET组织携带的合力。力在这些组织中增加的方式通过组织接合的参数来表征，即原位松弛，原位刚度，和施加IR力矩峰值时的组织力，然后进行比较(α<.05)。IR通过简单线性回归与LET组织的接合参数相关(α<.05)。
■在30°时，LET组织比前外侧组织表现出更少的原位松弛，60°,和90°的屈曲（P≤.04）和更大的原位刚度在30°和90°的屈曲（P≤.043）。LET组织在0°和30°弯曲时施加的峰值IR力矩处承受更大的力（P≤0.01）。IR与LET组织的原位松弛有关（R2≥0.88；P≤.0003）。
■与前外侧组织相比，LET增加了对胫骨IR的约束，特别是在30°时，60°,和90°的屈曲。胫骨的IR与LET组织的原位松弛呈正相关。
■将LET固定在60°的屈曲角度仍然可以在功能更相关的30°的屈曲角度中提供IR约束。术中固定LET组织时，外科医生应密切注意胫骨内部和/或外部旋转的角度，因为该手术参数与LET组织的原位松弛有关，因此,胫骨的IR量。
■（1）在尸体模型中比较力如何增加（即，接合）在分离的ACL重建后胫骨IR的前外侧组织中，以及在用LET增强ACL重建后的LET组织中，以及（2）确定胫骨IR是否与LET组织的接合有关。
■对照实验室研究。
■在0°处对9个人尸体膝盖施加IR矩，30°,60°,使用机器人操纵器弯曲90°。在2种状态下对每个膝盖进行了测试：（1）在完整的前外侧组织进行孤立的ACL重建后，以及（2）在使用改良的Lemaire技术进行LET后，LET组织在44N的张力下以弯曲60°固定。通过叠加确定前外侧组织和LET组织携带的合力。力在这些组织中增加的方式通过组织接合的参数来表征，即原位松弛，原位刚度，和施加IR力矩峰值时的组织力，然后进行比较(α<.05)。IR通过简单线性回归与LET组织的接合参数相关(α<.05)。
■在30°时，LET组织比前外侧组织表现出更少的原位松弛，60°,和90°的屈曲（P≤.04）和更大的原位刚度在30°和90°的屈曲（P≤.043）。LET组织在0°和30°弯曲时施加的峰值IR力矩处承受更大的力（P≤0.01）。IR与LET组织的原位松弛有关（R2≥0.88；P≤.0003）。
■与前外侧组织相比，LET增加了对胫骨IR的约束，特别是在30°时，60°,和90°的屈曲。胫骨的IR与LET组织的原位松弛呈正相关。
■将LET固定在60°的屈曲角度仍然可以在功能更相关的30°的屈曲角度中提供IR约束。术中固定LET组织时，外科医生应密切注意胫骨内部和/或外部旋转的角度，因为该手术参数与LET组织的原位松弛有关，因此,胫骨的IR量。
