Biomechanics and Movement Science, University of Delaware, Newark, DE, USA; Physical Therapy and Rehabilitation Department, Jouf University, Jouf, Saudi Arabia.
Department of Mechanical Engineering, University of Delaware, Newark, DE, USA.
J Electromyogr Kinesiol. 2022 Oct;66:102693. doi: 10.1016/j.jelekin.2022.102693. Epub 2022 Aug 22.
Interlimb and sex-based differences in gait mechanics and neuromuscular control are common after anterior cruciate ligament reconstruction (ACLR). Following ACLR, individuals typically exhibit elevated co-contraction of knee muscles, which may accelerate knee osteoarthritis (OA) onset. While directed (medial/lateral) co-contractions influence tibiofemoral loading in healthy people, it is unknown if directed co-contractions are present early after ACLR and if they differ across limbs and sexes. The purpose of this study was to compare directed co-contraction indices (CCIs) of knee muscles in both limbs between men and women after ACLR. Forty-five participants (27 men) completed overground walking at a self-selected speed 3 months after ACLR during which quadriceps, hamstrings, and gastrocnemii muscle activities were collected bilaterally using surface electromyography. CCIs of six muscle pairs were calculated during the weight acceptance interval. The CCIs of the vastus lateralis/biceps femoris muscle pair (lateral musculature) was greater in the involved limb (vs uninvolved; p = 0.02). Compared to men, women exhibited greater CCIs in the vastus medialis/lateral gastrocnemius and vastus lateralis/lateral gastrocnemius muscle pairs (p < 0.01 and p = 0.01, respectively). Limb- and sex-based differences in knee muscle co-contractions are detectable 3 months after ACLR and may be responsible for altered gait mechanics.
四肢间和性别间在步态力学和神经肌肉控制方面的差异在前交叉韧带重建（ACL 重建）后很常见。ACL 重建后，个体通常表现出膝关节肌肉的协同收缩增加，这可能加速膝关节骨关节炎（OA）的发生。虽然定向（内侧/外侧）协同收缩会影响健康人的胫骨股骨负荷，但尚不清楚 ACL 重建后早期是否存在定向协同收缩，以及它们是否存在于四肢和性别之间。本研究的目的是比较 ACL 重建后男性和女性双侧膝关节肌肉的定向协同收缩指数（CCI）。45 名参与者（27 名男性）在 ACLR 后 3 个月以自我选择的速度进行了地面行走，在此期间，使用表面肌电图双侧采集了股四头肌、腘绳肌和腓肠肌的肌肉活动。在负重期计算了 6 对肌肉的 CCI。股外侧肌/股二头肌（外侧肌肉）的 CCI 在患侧（与未患侧相比；p = 0.02）更大。与男性相比，女性在股直肌/外侧腓肠肌和股外侧肌/外侧腓肠肌的 CCI 更大（p < 0.01 和 p = 0.01）。ACL 重建后 3 个月可检测到膝关节肌肉协同收缩的肢体和性别差异，这可能是步态力学改变的原因。
