颈椎牵引过程中颈部肌电信号变化规律与力学特点

Variation of neck electromyography and mechanical characteristics during the process of cervical traction

目的观察颈椎牵引在不同加载质量和牵引角度时颈部肌肉表面肌电(electromyography,EMG)信号的变化特点,并与Any Body软件颈椎建模仿真所得的相关肌肉力活性变化特点进行对比,验证仿真结果的合理性。方法选取10例青年志愿者,行仰卧位颈椎牵引,JE-TB0810表面肌电仪测试颈部双侧胸锁乳突肌、斜方肌上部EMG信号,利用平均肌电值(average EMG,AEMG)和平均功率频率(mean power frequency,MPF)分析颈部EMG信号的变化规律。结果斜方肌上部和胸锁乳突肌AEMG均随着加载质量和牵引角度的增大而增大,差异均具有统计学意义(P<0.05),斜方肌上部AEMG较胸锁乳突肌高,差异有统计学意义(P<0.05);2对肌肉在不同牵引角度和加载质量下MPF比较,差异无统计学意义(P>0.05);实验结果与颈椎牵引建模仿真所得斜方肌上部和胸锁乳突肌肌肉力活性特点相符。结论仿真结果具有一定的合理性,临床上可根据颈部肌肉的兴奋程度和疲劳时间合理施加牵引重量,既达到治疗效果,也提高患者的舒适性,为颈椎牵引设备的进一步研制和改进提供重要参考。

Objective To observe changes of surface electromyography （sEMG） in cervical traction under differ- ent loading weight and at different angles, and compare the muscle activity changes obtained by experiment with simulation results obtained by AnyBody cervical modeling, so as to verify the rationality of the simulation results. Methods Ten young volunteers were selected to test the sEMG signals of bilateral sternocleidomastoid （SCM） and upper trapezius （UT） muscles during supine cervical traction by using JE-TB0810 surface EMG device. Theaverage EMG （AEMG） and mean power frequency （MPF） were used to analyze the variation patterns of sEMG in cervical spine. Results The AEMG values of SCM and UT muscles increased as the loading weight and trac- tion angles increasing, showing statistically significant difference （ P 〈 0.05）. The AEMG values of UT muscles was higher than that of SCM muscles, also having statistically significant difference （ P 〈 O. 05 ）. No statistical differences were found in the MPF values at different traction angles or under different loading weight for both SCM and UT muscles （ P 〉 0. 05）. The experimental results of muscle force activity both in SCM and UT muscles were consistent with those obtained from modeling and simulation of cervical traction. Conclusions The simula- tion results are verified and can provide an important reference for further development and improvement of the cervical traction device. It indicates that traction weight should be loaded reasonably according to the excitation and fatigue of the cervical muscles in clinic with both insuring the treatment effect and improving patient＇ s comfort as well.