Rutherford Derek J, Hubley-Kozey Cheryl L, Stanish William D, Dunbar Michael J
School of Biomedical Engineering, Faculty of Engineering, Dalhousie University, Halifax, Nova Scotia, Canada.
Clin Biomech (Bristol). 2011 May;26(4):377-83. doi: 10.1016/j.clinbiomech.2010.11.018. Epub 2010 Dec 24.
Neuromuscular strategies during walking in individuals with knee osteoarthritis are being explored for diagnostic information; however, isolating differences to disease progression is difficult given walking velocity decreases with osteoarthritis severity. This study investigated lower extremity electromyograms during walking in asymptomatic individuals and individuals with different severities of knee osteoarthritis who walked with similar self-selected velocities.
Muscle activity in lateral and medial gastrocnemius, vastus lateralis and medialis, rectus femoris and the lateral and medial hamstrings was monitored during self-selected walking in 230 subjects with asymptomatic knees, moderate and severe knee osteoarthritis. Sixteen asymptomatic individuals, 16 individuals with moderate and 15 individuals with severe knee osteoarthritis were identified based on similarities in average walking velocity. Principal component analysis was employed to derive amplitude and temporal characteristics of the electromyographic (EMG) waveforms. Analysis of variance models tested for group and muscle differences in principal pattern scores (α=0.05). Bonferroni post hoc testing was utilized on all significant findings.
Despite similar walking velocities, individuals with moderate knee OA had elevated and prolonged quadriceps and elevated lateral hamstring activity compared to asymptomatic individuals (P<0.05). A diminished phase shift between medial and lateral gastrocnemius muscle activation, greater and prolonged lateral compared to medial hamstring activation were found in the severe group compared to asymptomatic and moderate knee OA groups (P<0.05).
Lower extremity neuromuscular function during walking is altered with the presence and severity of knee osteoarthritis and not simply a direct function of walking velocity.
目前正在探索膝关节骨关节炎患者行走时的神经肌肉策略以获取诊断信息；然而，鉴于行走速度会随着骨关节炎严重程度的增加而降低，因此很难将差异与疾病进展区分开来。本研究调查了无症状个体以及患有不同严重程度膝关节骨关节炎且以相似的自我选择速度行走的个体在行走过程中的下肢肌电图。
在230名无症状膝关节、中度和重度膝关节骨关节炎患者自我选择行走过程中，监测腓肠肌外侧头和内侧头、股外侧肌和股内侧肌、股直肌以及腘绳肌外侧头和内侧头的肌肉活动。根据平均行走速度的相似性，确定了16名无症状个体、16名中度膝关节骨关节炎个体和15名重度膝关节骨关节炎个体。采用主成分分析来推导肌电图（EMG）波形的幅度和时间特征。方差分析模型用于检验主模式得分在组间和肌肉间的差异（α = 0.05）。对所有显著发现进行Bonferroni事后检验。
尽管行走速度相似，但与无症状个体相比，中度膝关节骨关节炎患者的股四头肌活动增强且持续时间延长，腘绳肌外侧头活动增强（P < 0.05）。与无症状和中度膝关节骨关节炎组相比，重度组腓肠肌内侧头和外侧头激活之间的相位偏移减小，腘绳肌外侧头与内侧头相比激活更强且持续时间更长（P < 0.05）。
行走过程中的下肢神经肌肉功能会随着膝关节骨关节炎的存在和严重程度而改变，而不仅仅是行走速度的直接函数。
