脑卒中患者下肢肌在被动、助力和抗阻等动态运动负荷下表面肌电信号特征研究

Characteristics of Dynamic Contractions on Surface Electromyography Single of Stroke Patients Induced from Low Limb Muscle When Exercising Passively, Exercising Initiatively with Assitant and Against Resistance

目的观察在被动、助力和主动抗阻等动态运动负荷下脑卒中偏瘫患者下肢肌肉表面肌电信号的特征。方法对24例脑卒中患者(偏瘫组)和17例正常对照组在被动、助力和主动抗阻等动态运动负荷下诱发双侧下肢屈伸髋及膝关节,记录肌电信号并进行线性时、频分析。结果偏瘫组中位频率(MF)、平均功率频率(MPF)均值明显减小,平均肌电值(AEMG)均值显著增大(P<0.001);活动侧的MF、MPF显著小于非活动侧(P<0.001),MF、MPF均值助力>被动>抗阻活动(P<0.05),AEMG均值抗阻>助力>被动活动,MF、MPF均值协同肌增大,AEMG均值拮抗肌及拮抗协同肌>主动肌及主动协同肌(P<0.01);健侧活动侧MF、MPF均值明显增高,患侧活动侧和健侧非活动侧明显下降;活动侧MF、MPF均值股外侧肌(VL)最大而非活动侧股内侧肌(VM)最大,活动侧、非活动侧AEMG均值股二头肌(BF)最大;偏瘫组双下肢四组肌肉MF、MPF均值减小,患侧以股直肌(RF)最小,健侧以BF最小(P<0.01),双下肢的AEMG均值明显增大,尤以BF增高最明显,特别是健侧下肢;四组肌肉AEMG均值随着运动负荷的增加逐渐增大,其中BF始终是最大,而VM随着运动负荷的增加增大最明显。结论脑卒中偏瘫患者MF、MPF均值明显减小,而AEMG均值增大;活动侧的MF、MPF小于非活动侧,其中健侧活动侧明显增高,而患侧活动侧和健侧非活动侧明显下降;MF、MPF均值助力>被动>抗阻活动;AEMG均值抗阻>助力>被动活动,MF、MPF均值协同肌增大,AEMG均值拮抗肌及拮抗协同肌>主动肌及主动协同肌。

Objective To investigate the characteristics of the dynamic contractions on the surface electromyography （sEMG） single of stroke patients induced from the low limb muscle when exercising passively, exercising initiatively with assistant and against resistance. Methods 24 stroke patients with hemiplegia and 17 normal subjects were tested with sEMG under a dynamic contractions in coxa and knee flexion and extension passively, initiatively with assistant and against resistance. The myoelectric signals were col lected and processed by linear time and frequency domain method. Results The values of median frequency （MF） and mean power frequency （MPF） of stroke group were significantly lower, but the value of average EMG （AEMG） was higher （P〈0. 001）. The values of MF and MPF in activity side were lower than that in non-activity side （P〈0. 001）. The values of MF and MPF when exercising passively were higher than that when exercising with resistance （ P〈0.05）. The value of AEMG when exercising with resistance was highest. The values of MF and MPF in the synergist muscle were higher. The values of AEMG in the antagonistic muscle and synergist muscle were higher than that agonist and synergist muscle （P〈0.01）. The values of MF and MPF in non-paretic exercising side were higher significantly, but in paretic exercising side and non-paretic silent side were lower. The values of MF and MPF in exercising side from vastus lateralis （VL） were the highest. The values of AEMG in exercising side and no,exercising side from biceps femoris （BF） were the highest. The values of MF and MPF in low limb of stroke group reduced, that in rectus femoris （RF） from paretic side was the lowest; that in BF from non-paretic side was the lowest （P〈0.01）. The value of AEMG in low limb of stroke group was high significantly, especially in BF from the low limb of the non paretic side in stroke patients. The values of AEMG in four group muscles gradually were higher following the higher exercising load, and that in the BF was the highest, and that in vastus medialis （VM） rose significantly. Conclusion The values of MF and MPF of stroke patients with hemiplegia reduce significantly, but the value of AEMG is higher. The values of MF and MPF in exercising side are lower than that in non-exercising side and non-paretic exercising side rising significantly, but that in paretic exercising side and non-paretic silent side reduce significantly. The values of MF and MPF in assistant exercise are higher than that in passive exercise and resistance exercise, but the value of AEMG in resistance exercise is higher than that in assistant exercise and in passive exercise. The values of MF and MPF in synergist muscle rise, but the values of AEMG in antagonist and synergist muscle are higher than that agonist and synergist muscle.