脑卒中患者膝关节拮抗肌协同收缩率的变化规律

Antagonistic Co-contraction Ratios of Dynamic Contraction during Stroke Patient's Knees Exercise

目的观察在被动、主动-助力和抗阻等动态运动负荷下对脑卒中患者膝关节拮抗肌群协同收缩率变化的特征。方法24例脑卒中患者作为偏瘫组和17名正常人作为正常组参加本实验研究,利用动态运动负荷诱发双侧下肢膝关节屈伸运动,采用表面电极引导和记录肌电信号并进行线性时、频分析,然后计算协同收缩率并进行单因素及多因素方差分析。结果偏瘫组下肢的中位频率(MF)、平均功率频率(MPF)协同收缩率患侧明显增大而健侧明显下降,平均肌电值(AEMG)协同收缩率患侧明显下降而健侧明显增大(P<0.01);MF和AEMG协同收缩率活动侧明显小于非活动侧(P<0.05);MPF协同收缩率被动活动明显减少,AE-MG协同收缩率随运动负荷增大而减少(P<0.001)。结论偏瘫患者患侧拮抗肌群运动单位肌电募集过度,兴奋的同步化程度降低,肌力下降,而健侧拮抗肌群运动单位肌电募集和运动单位兴奋的同步化过度,肌力增加。

Objective To investigate the influence of dynamic contraction to antagonist coactivity ratios during the stroke patient＇s knees exercise passively initiatively and resistively.Methods 24 stroke patients as observation group and 17 normal subjects as control group had performed dynamic contractions in knee flexion and extension.The electromyography signals were collected by surface electrode and then processed by linear time-and frequency-domain method.And then the antagonistic coactivity ratio was analyzed with factors statistics.Results The antagonist coactivity ratios of MF（median frequency） and MPF（mean power frequency） in paretic side of patients got high significantly but in non-paretic side got low significantly.But the antagonistic coactivity ratios of AEMG（average EMG） in paretic side got low and in non-paretic side got high significantly（P〈0.01）.The antagonist coactivity ratios of MF and AEMG in activity side were lower than in non-activity side（P〈0.05）.The antagonist coactivity ratios of MPF in exercise passively were lower significantly.The antagonist coactivity ratios of AEMG were lower following as the work load increased（P〈0.001）.Conclusion The motor unites are collected excessively in antagonist from paretic side of the stroke patient.The level of the synchronization of the excitement got low.The muscle strength got weak.But both the motor unites collected and the motor unites excited in antagonist from non-paretic side are excessive.The muscle strength get strong.