Batty Lachlan M, Feller Julian A, Damasena Iswadi, Behrens Gerrit, Devitt Brian M, Hartwig Taylor, McClelland Jodie A, Webster Kate E
OrthoSport Victoria Research Unit, Melbourne, Victoria, Australia.
St. Vincent's Hospital Melbourne, Victoria, Australia.
Orthop J Sports Med. 2020 Aug 26;8(8):2325967120946328. doi: 10.1177/2325967120946328. eCollection 2020 Aug.
Deficits in neuromuscular control are common after anterior cruciate ligament (ACL) reconstruction and may be associated with further knee injury. The knee valgus angle during a single-leg squat (SLS) is one measure of neuromuscular performance.
To determine whether the knee valgus angle during SLS changes between 6 and 12 months after ACL reconstruction and to assess how the operative knee valgus angle compares with that of the contralateral side.
Case series; Level of evidence, 4.
A cohort of 100 patients with uninjured contralateral knees were assessed at 6 and 12 months after primary hamstring autograft ACL reconstruction. Participants performed the SLS on each leg, and the knee valgus angle was measured via frame-by-frame video analysis at 30° of flexion and at each patient's maximum knee flexion angle.
For the operative limb at 30° of flexion, a small but statistically significant reduction was noted in the valgus angle between 6 and 12 months (5.46° vs 4.44°; = .002; effect size = 0.24). At 6 months, a slightly higher valgus angle was seen in the operative limb compared with the nonoperative limb (5.46° vs 4.29°; = .008; effect size = 0.27). At maximum flexion, no difference was seen between limbs in the valgus angle at either 6 or 12 months, and no change was seen in the operative limb between 6 and 12 months. At 6 months and 30° of knee flexion, 13 patients had a valgus angle greater than 10°. This group also had a higher mean valgus angle in the contralateral limb compared with the contralateral limb in the other 87 patients (8.5° vs 3.65°; < .001).
During a controlled SLS, the knee valgus angle remained essentially constant, and minimal limb asymmetries were present over the 6- to 12-month postoperative period, a time when athletes typically increase their activity levels. Whether changes or asymmetries will be seen with more dynamically challenging tasks remains to be determined. When present, high valgus angles were commonly bilateral.
前交叉韧带（ACL）重建术后神经肌肉控制缺陷很常见，可能与膝关节进一步损伤有关。单腿深蹲（SLS）时的膝外翻角度是神经肌肉功能的一项指标。
确定ACL重建术后6至12个月期间SLS时的膝外翻角度是否发生变化，并评估手术侧膝外翻角度与对侧相比情况如何。
病例系列；证据等级，4级。
对100例对侧膝关节未受伤的患者在自体腘绳肌腱移植初次ACL重建术后6个月和12个月进行评估。参与者每条腿都进行SLS，通过逐帧视频分析在屈膝30°以及每位患者的最大屈膝角度时测量膝外翻角度。
对于手术侧肢体在屈膝30°时，6至12个月期间外翻角度有小幅度但具有统计学意义的降低（5.46°对4.44°；P = 0.002；效应量 = 0.24）。在6个月时，手术侧肢体的外翻角度略高于非手术侧肢体（5.46°对4.29°；P = 0.008；效应量 = 0.27）。在最大屈膝时，6个月或12个月时两侧肢体的外翻角度均无差异，且手术侧肢体在6至12个月期间无变化。在6个月且屈膝30°时，13例患者的外翻角度大于10°。与其他87例患者的对侧肢体相比，该组患者对侧肢体的平均外翻角度也更高（8.5°对3.65°；P < 0.001）。
在控制的SLS过程中，膝外翻角度基本保持恒定，在术后6至12个月期间肢体不对称最小，而这一时期运动员通常会增加活动量。在更具动态挑战性的任务中是否会出现变化或不对称仍有待确定。当出现高外翻角度时，通常是双侧的。
