Markolf Keith L, Graves Benjamin R, Sigward Susan M, Jackson Steven R, McAllister David R
Biomechanics Research Section, Department of Orthopaedic Surgery, University of California at Los Angeles Rehabilitation Center, 1000 Veteran Avenue, Room 21-67, Los Angeles, CA 90095-1759, USA.
J Bone Joint Surg Am. 2007 Nov;89(11):2351-8. doi: 10.2106/JBJS.F.01086.
In patients with a Grade-3 injury, reconstructions of the lateral collateral ligament, popliteus tendon, and popliteofibular ligament are commonly performed in conjunction with a reconstruction of the posterior cruciate ligament. The objectives of this study were (1) to compare the abilities of three types of posterolateral graft reconstruction to restrain external tibial rotation and alter forces in a posterior cruciate graft and (2) to compare tibial rotations and posterior cruciate graft forces associated with two levels of initial posterolateral graft tension.
Forces in the posterior cruciate ligament were recorded as the knee was extended from 120 degrees to 0 degrees and a 5-N-m external tibial torque was applied. The posterior cruciate ligament was reconstructed, and external tibial rotation and the forces in the posterior cruciate graft were recorded. These measurements were again recorded after sectioning of the posterolateral structures and after reconstruction of the lateral collateral ligament, alone as well as in combination with reconstruction of the popliteus tendon and in combination with reconstruction of the popliteofibular ligament.
With the lateral collateral ligament intact, removal of the popliteus tendon from its femoral origin significantly increased external tibial rotation. Applying tension to a popliteus or popliteofibular graft internally rotated the tibia, with no significant difference between the rotations caused by the tensioning of the two grafts. Tibial rotation was significantly greater when graft tensioning had been performed with the tibia free to rotate than it was when the tensioning had been done with the tibia locked in neutral rotation. With an applied external tibial torque, a reconstruction of the lateral collateral ligament alone was not sufficient to reduce posterior cruciate graft forces to normal. The addition of a popliteus or popliteofibular reconstruction to the lateral collateral ligament reconstruction significantly reduced posterior cruciate graft forces to normal (or below normal) levels. The external rotations associated with these two combined reconstructions were equivalent and significantly less than that in the intact knee. Increasing tension in either the popliteus or the popliteofibular graft from 10 to 30 N significantly decreased external rotation.
The posterolateral grafts acted to resist applied external torque, thereby off-loading the posterior cruciate graft. Popliteus and popliteofibular grafts were more favorably aligned than a lateral collateral ligament graft to resist external rotation, and they had similar effects.
在3级损伤患者中，外侧副韧带、腘肌腱和腘腓韧带的重建通常与后交叉韧带重建同时进行。本研究的目的是：（1）比较三种类型的后外侧移植物重建抑制胫骨外旋和改变后交叉韧带移植物中力的能力；（2）比较与两种初始后外侧移植物张力水平相关的胫骨旋转和后交叉韧带移植物力。
在膝关节从120度伸展至0度并施加5 N·m的胫骨外扭矩时，记录后交叉韧带中的力。重建后交叉韧带，并记录胫骨外旋和后交叉韧带移植物中的力。在切断后外侧结构后以及单独重建外侧副韧带后，以及与腘肌腱重建联合以及与腘腓韧带重建联合后，再次记录这些测量值。
在外侧副韧带完整的情况下，将腘肌腱从其股骨起点处切断会显著增加胫骨外旋。对腘肌腱或腘腓韧带移植物施加张力会使胫骨内旋，两种移植物张力引起的旋转之间无显著差异。当胫骨自由旋转时进行移植物张力调节时，胫骨旋转明显大于胫骨锁定在中立旋转位时进行张力调节时的情况。施加胫骨外扭矩时，单独重建外侧副韧带不足以将后交叉韧带移植物力降低至正常水平。在外侧副韧带重建中增加腘肌腱或腘腓韧带重建可显著将后交叉韧带移植物力降低至正常（或低于正常）水平。与这两种联合重建相关的外旋相等，且明显小于完整膝关节中的外旋。将腘肌腱或腘腓韧带移植物中的张力从10 N增加到30 N会显著减少外旋。
后外侧移植物起到抵抗施加的外扭矩的作用，从而减轻后交叉韧带移植物的负荷。腘肌腱和腘腓韧带移植物在抵抗外旋方面比外侧副韧带移植物排列更有利，且它们具有相似的效果。
