基于表面肌电信号对比分析的下肢假肢佩戴者提物补偿机制研究

Study on Compensation Mechanism of the Lower Limb Prosthesis When Lifting Based on Surface Electromyography Comparison

目的本研究通过比较肢残者健体与残体生物力学参数的差异,分析下肢假肢佩戴者的健体在提物过程中对残体的补偿机制以及提物方法和负重水平对补偿机制的影响。方法以弯腰不屈膝和屈膝不弯腰两种提物方式以及三个重量水平作为实验自变量。通过肌电仪记录5名健体者和5名下肢截肢者在试验过程中6块肌肉(左右背阔肌、左右竖脊肌和左右股直肌)的肌电数据。通过表面肌电的时域分析,对比分析肢残者两侧以及实验组与对照组在6块主要活动肌群肌力的差异。结果对于积分肌电值(iEMG),残疾人被试在残疾一侧的iEMG指标值都要显著小于其健体一侧,背阔肌(P<0.001,n=90)、竖脊肌(P<0.01,n=90)、股直肌(P<0.001,n=90)。残疾被试的股直肌健体一侧明显大于健康被试(P<0.05,n=90);残疾人残体一侧背阔肌明显高于健康被试者(P<0.05,n=45)。结论提物活动过程中,残疾人假肢一侧的股直肌和腰部的持久力和爆发力均弱于其他身体部位,健体一侧的背部、腿部和腰部提供能力补偿。

Objective The study is to analyze the compensation mechanism of the sound side to the amputated side in the process of lifting with different lifting strategies and loads. Methods Two lifting strategies and three levels of loads were chosen. The right/left LD （latissimus dorsi） left/right ES （erector spinal） and right/left RF （rectus femora） of 5 able -bodied people and 5 below -hip amputees＇sEMG （surface electromyography） signals were recorded. Through the analysis of the sEMG signals in time domain, we found how differently each muscle of below - hip amputees and able - bodied people functions during lifting task. Results iEMG （ integrated eleetromyography） of the amputees＂ LD is significantly lower than that of healthy part （ P 〈 0.001, n = 90） as well as ES （ P 〈 0.01, n = 90） and RF （P 〈0. 001, n =90）. And iEMG of the below- hip amputees＇RF of healthy leg is bigger than that of the able - bodied （ P 〈 0.05, n = 90）, as well as the LD （ P 〈 0.05, n = 45 ）. Conclusion Below - hip amputees＂ erector spinals and rectus femora are weaker than other body parts. The back, torso and leg of healthy part provide compensations for the weakness.