Laxité du genou dans les lésions complexes antérolatérales par rapport aux lésions de la corne postérieure du ménisque médial dans les lésions du ligament croisé antérieur : étude cadavérique

Abstract

IntroductionThere is considerable debate regarding the function of anterolateral knee structures, including the anterolateral ligament (ALL) and anterolateral capsule, as knee stabilizers in anterior cruciate ligament (ACL) injured knees. Medial meniscus posterior horn (MMPH) injuries have also been associated with increased knee laxity in ACL injured knees. The purpose of this cadaveric biomechanical study was to compare the effects of the anterolateral complex (ALC) injury and meniscectomy of MMPH on knee laxity in ACL injured knees. HypothesisALC injury would have a greater effect on internal rotational laxity in ACL-injured knee than meniscectomy of MMPH. Material and methodsMatched-pair 10 fresh-frozen cadaveric knees underwent biomechanical evaluation of knee laxity. After testing the intact knee and ACL sectioned knee (ACL−) in matched-pair 10 fresh-frozen cadaveric knees, two groups were established: an ALC sectioning (ACL−/ALC−) group (n=5) and a MMPH meniscectomy (ACL−/MMPH−) group (n=5). Knee laxity was measured in terms of internal-external rotation, anterior-posterior translation, and varus-valgus angulation for each condition at knee flexion angles of 0°, 30°, 60° and 90°. ResultsAfter the additional sectioning of the ALC (ACL−/ALC−), the mean internal rotation at 0°, 30°, 60° and 90° of knee flexion showed the greater internal rotation laxity compared than intact knee (p=0.020, 0.011, 0.005 and <0.001). It also significantly increased anterior translation from ACL− at 30° and 60° (p=.011 and .005). In contrast, additional meniscectomy of the MMPH (ACL−/MMPH−) significantly increased external rotation laxity compared to intact knee (p=0.021, 0.018 and 0.024) and ACL− (p=0.037, 0.011 and 0.025) at 30°, 60° and 90°. ACL−/MMPH− also resulted in significantly increased anterior translation from ACL− at 30°, 60° and 90° (p=0.004, 0.008 and 0.002). DiscussionIn conclusion, the anterolateral complex, which include the ALL and anterolateral capsule, may play an important role in stabilizing the knee against internal rotation and anterior translation, while the MMPH may contribute to resisting external rotation and anterior translation stability in ACL-injured knee. Level of evidenceII, Controlled laboratory study.