Department of Physical Therapy, University of Delaware, Newark, DE, USA; Biomechanics and Movement Science Program, University of Delaware, Newark, DE, USA.
Division of Physical Therapy, School of Health and Rehabilitation Sciences, The Ohio State University, Columbus, OH, USA; Sports Medicine Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
J Electromyogr Kinesiol. 2022 Oct;66:102694. doi: 10.1016/j.jelekin.2022.102694. Epub 2022 Aug 17.
Kinematic and kinetic changes following anterior cruciate ligament (ACL) rupture and reconstruction (ACLR) have been fundamental to the understanding of mechanical disrupted load as it contributes to the development of posttraumatic osteoarthritis. These analyses overlook the potential contribution of muscle activity as it relates to the joint loading environment. Males and females classified as non-copers present with unique knee kinematics and kinetics after ACL injury. The purpose of this study was to perform sex-specific analyses in these individuals to explore muscle activity timing during gait after ACL rupture. Thirty-nine participants (12 females, 27 males) were enrolled. Muscle activity during gait was evaluated before and after pre-operative physical therapy, and six months after ACLR. Surface electromyography data were evaluated to determine timing (e.g., the time the muscle activity begins ('On') and ends ('Off')) for seven muscles: vastus lateralis and medialis (VL, VM), lateral and medial hamstrings (LH, MH), lateral and medial gastrocnemius (LG, MG), and soleus (SOL). General linear models with generalized estimating equations detected the effects of limb and time for muscle activity timing. Males presented with more limb asymmetries before and after pre-operative PT in the VL On (p < 0.001) and Off (p = 0.007), VM On and Off (p < 0.001), and MH off (p < 0.001), but all limb differences resolved by six months post ACLR. Changes in muscle activity in males were pervasive over time in both limbs. Females presented with no interlimb differences pre-operatively, and only involved limb VL off (p = 0.027) and VM off (p = 0.003) and the LH off in both limbs (p < 0.038) changed over time. Our data indicate that inter-limb differences in muscle activity across time points and changes in muscle activity timing over the course of physical therapy were sex specific. Males presented with more inter-limb differences in muscle activity across time points, and females presented with fewer asymmetries before and after pre-operative physical therapy. These data support that sex-specific adaptations should be taken into consideration when assessing biomechanical changes after ACLR.
前交叉韧带（ACL）断裂和重建（ACLR）后的运动学和动力学变化对于理解机械负荷中断至关重要，因为它有助于创伤后骨关节炎的发展。这些分析忽略了肌肉活动的潜在贡献，因为它与关节加载环境有关。被归类为非适应者的男性和女性在 ACL 损伤后会出现独特的膝关节运动学和动力学。本研究的目的是对这些个体进行性别特异性分析，以探讨 ACL 破裂后步态中的肌肉活动时机。39 名参与者（12 名女性，27 名男性）入组。在术前物理治疗之前和 ACLR 后 6 个月评估步态中的肌肉活动。评估表面肌电图数据以确定 7 块肌肉的时机（例如，肌肉活动开始（“开”）和结束（“关”）的时间）：股外侧肌和股内侧肌（VL、VM）、外侧和内侧腘绳肌（LH、MH）、外侧和内侧腓肠肌（LG、MG）和比目鱼肌（SOL）。使用广义估计方程的广义线性模型检测了肌肉活动时机的肢体和时间的影响。男性在术前 PT 前后的 VL 开（p<0.001）和关（p=0.007）、VM 开和关（p<0.001）以及 MH 关（p<0.001）时表现出更多的肢体不对称，但所有肢体差异在 ACLR 后 6 个月时均得到解决。男性的肌肉活动变化随着时间的推移在两个肢体中普遍存在。女性术前没有肢体间差异，只有受累肢体 VL 关（p=0.027）和 VM 关（p=0.003）以及双侧 LH 关（p<0.038）随时间变化。我们的数据表明，肌肉活动在时间点上的肢体间差异以及肌肉活动时机在物理治疗过程中的变化具有性别特异性。男性在不同时间点的肌肉活动肢体间差异更大，而女性在术前物理治疗前后的不对称性较少。这些数据支持在评估 ACLR 后生物力学变化时应考虑性别特异性适应。
