肌力训练对脑卒中恢复期偏瘫患者大腿表面肌电的影响

目的 探讨脑卒中恢复期偏瘫患者肌力训练对大腿肌群表面肌电(sEMG)信号特征的影响,为脑卒中患者的康复治疗提供客观依据.方法 共选取35例脑卒中恢复期偏瘫患者,分为治疗组(n=19)和对照组(n=16),治疗组给予6周的肌力训练,并在治疗前后在患侧膝关节屈伸最大等长收缩(MIVC)时记录股内侧肌、股直肌、股外侧肌、股二头肌、半腱半膜肌的sEMG信号,计算膝关节屈伸力矩值、均方根值(RMS)及其相应协同收缩率;对照组不给予康复训练,仅与治疗组同时进行上述指标测量.结果 治疗组治疗后患者患侧屈膝及伸膝MIVC力矩均较治疗前明显改善屈膝:(18.02±6.52)nm比(13.12±5.79)nm,伸膝:(45.72±17.21)nm比(34.76±17.19)nm,均P＜0.05],而伸屈膝协同收缩率较治疗前无明显变化.对照组伸屈膝MIVC力矩和协同收缩率治疗前后差异则无统计学意义(均P＞0.05).治疗组治疗后患者患侧大腿股直肌、股外侧肌、半腱半膜肌作为主动肌时的RMS值均较治疗前明显改善(146.60±60.85)μV比(97.02±57.17)μV,(172.65±60.73)μV比(131.46±52.15)μV,(188.69±89.60)μV比(130.57±73.76)μV,均P＜0.05],而股内侧肌、股二头肌的RMS值在治疗前后无明显变化,对照组治疗前后各肌的RMS值则无变化(均P＞0.05).结论 肌力训练可改善脑卒中恢复期偏瘫患者下肢屈伸肌力,但并不会增强下肢伸屈肌的异常收缩.sEMG结合力矩测量能更全面评估偏瘫肢体功能状态.

Effect of muscle strength exercise on surface electromyography over thigh in stroke patients with hemiplegia during convalescence

Objective To explore the effect of muscle strength exercise on surface electromyography (sEMG) over thigh in stroke patients with hemiplegia during convalescence so as to gain objective evidence for rehabilitation therapy of stroke patients. Methods Thirty-five stroke patients with hemiplegia during convalescence were enrolled in this study, and were divided into two groups, treatment group (n=19) and control group (n=16). The treatment group underwent muscle strength exercise for 6 weeks. Before and after treatment, sEMG signals over vastus medialis (VM), rectus femoris muscle (RF),vastus lateralis (VL), biceps femoris (BF) and semitendinosus (ST) and semimembranosus (SM) during maximal isometric voluntary contraction (MIVC) of the affected knee extension and flexion were recorded.Torque of knee joint extension and flexion, root mean square (RMS) and co-contraction ratio (CR) were computed. No rehabilitation training was performed in control group. The above mentioned indexes of control group were also recorded. Results After treatment, obvious changes were observed in MIVC torque of the affected knee flexion (18.02±6.52) nm vs (13.12±5.79) nm, P＜0.05] and extension (45.72±17.21 ) nm vs (34.76± 17.19) nm, all P＜0.05 ]. There were no significant differences in CR of flexion and extension. No statistical difference was observed in MIVC torque and CR of flexion and extension before and after treatment in control group (all P＞0.05). RMS value significantly improved when RF, VL, ST and SM over affected thigh were agonist after treatment (146.60±60.85) μV vs (97.02±57.17) μV, (172.65±60.73) μV vs ( 131.46 ± 52.15 ) μV, ( 188.69 ± 89.60) μV vs ( 130.57 ± 73.76) μV, all P＜0.05 ]. There were no significant differences of RMS value in the VM and BF before and after treatment (all P＞0.05), and no RMS changes were noted in control group (all P＞0.05). Conclusions Strength exercise may improve strength of flexion and extension over lower limbs in stroke patients with hemiplegia during convalescence, however, it will not induce abnormal contraction of flexion and extension. sEMG combined with torque measurement may assess functional status of hemiplegic limbs effectively.