School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, Scotland, UK.
Arthritis Care Res (Hoboken). 2019 May;71(5):651-660. doi: 10.1002/acr.23688.
Muscle co-activation has been shown to be elevated in individuals with knee osteoarthritis (OA) during gait. Comparisons of muscle co-activation across different activities of daily living such as stair negotiation have yet to be explored. The aim of this study was to explore muscle co-activation across different activities of daily living in patients with knee OA.
Muscle co-activation was assessed in 77 symptomatic knee OA patients (mean ± SD age 62.5 ± 8.1 years, body mass index 29.4 ± 6.0 kg/m , and sex 48:29 female:male) using electromyography (EMG), during a series of walking, stair negotiation (ascent, descent), and sit-to-walk activities. EMG was recorded from 7 sites, mediolateral gastrocnemius, biceps femoris, semitendinosus, vastus lateralis/medialis, and rectus femoris, and normalized to maximal voluntary isometric contraction. Correlation was used to assess the consistency of co-activation across activities. Repeated-measures analysis of variance assessed the muscle combination by activity differences.
Muscle co-activation was highest during stair ascent. When comparing muscle combinations within the same activity, we found that correlations ranged from r = 0.003 to r = 0.897, of which 80% of the combinations were significant. Between activities, muscle co-activation was significantly different (P < 0.05). Mediolateral muscle co-activation was higher than hamstrings/quadriceps across activities.
Two muscle co-activation strategies were observed during activities of daily living in patients with knee OA to maintain stability. Muscle co-activation was higher during more challenging activities, particularly when the joint was accepting load. Mediolateral muscle co-activation was higher than hamstrings/quadriceps, so that mediolateral co-activation was thought to be a stabilization mechanism, while hamstrings/quadriceps co-activation responds to knee flexion moments, suggesting that different muscle combinations may have different roles in responding to joint demand.
在膝关节骨关节炎（OA）患者的步态中，已显示出肌肉协同激活增加。尚未探讨不同日常活动（如楼梯上下）之间的肌肉协同激活比较。本研究旨在探讨膝关节 OA 患者不同日常活动中的肌肉协同激活。
通过肌电图（EMG）评估 77 例有症状的膝关节 OA 患者（平均年龄±标准差为 62.5±8.1 岁，体重指数 29.4±6.0kg/m ，性别 48:29 女性：男性）在一系列行走、楼梯上下（上、下）和从坐到站的活动中的肌肉协同激活。EMG 从 7 个部位记录，包括中外侧腓肠肌、股二头肌、半腱肌、股外侧肌/内侧肌和股直肌，并归一化为最大随意等长收缩。相关性用于评估活动之间协同激活的一致性。重复测量方差分析评估了不同活动的肌肉组合差异。
楼梯上时肌肉协同激活最高。当比较同一活动中的肌肉组合时，我们发现相关系数范围从 r = 0.003 到 r = 0.897，其中 80%的组合具有统计学意义。在活动之间，肌肉协同激活存在显著差异（P < 0.05）。在所有活动中，外侧肌与比目鱼肌/股四头肌的协同激活均高于比目鱼肌/股四头肌。
在膝关节 OA 患者的日常活动中观察到两种肌肉协同激活策略，以维持稳定性。在更具挑战性的活动中，肌肉协同激活更高，特别是在关节承受负荷时。外侧肌与比目鱼肌/股四头肌的协同激活更高，因此外侧肌协同激活被认为是一种稳定机制，而比目鱼肌/股四头肌的协同激活则对应膝关节的弯曲力矩，这表明不同的肌肉组合可能在应对关节需求方面具有不同的作用。
