Hu Y L, Yu Y J, Huang X Y, Wang Z Y, Wu L
School of Public Health, Medical College, Wuhan University of Science and Technology, Wuhan 430065, China.
Hubei Province Key Laboratory of Occupational Hazard Identification and Control, Clinical Medicine Department, Medical College, Wuhan University of Science and Technology, Wuhan 430065, China.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2022 Jan 20;40(1):50-53. doi: 10.3760/cma.j.cn121094-20201106-00618.
To simulate and evaluate the scraping and grinding work of workers with different spinal anteversion angles, and to explore the effects of different anteversion angles on the erector spinae muscles of scrapers. In November 2019, 16 male college student volunteers were recruited to simulate workers' scraping and grinding work. The parameters were 25°, 15 times/min, 15°, 30 times/min, 5°, 60 times/min respectively. The surface electromyography (sEMG) was used to collect the electromyographic signals of the erector spinae muscles, and the surface electromyographic characteristics of the erector spinae muscles were evaluated with Borg Scale. There were significant differences between the maximum voluntary contraction percentage (MVE%) of the left and right erector spinae muscles groups in the three groups with different spinal anteversion angles ((left)=13.41, (left)<0.001; (right)=4.74, (right)=0.005) , and the EMG amplitude was higher at 25°, 15 times/min. At 15°, 30 times/min, MVE% of the left side was significantly higher than that of the right side (=2.58, =0.021) . There was significant difference in the mean power frequency (MPF) of the right erector spinae muscle in the three groups (=9.42, <0.001) , but there was no significant difference in the MPF of the left erector spinae muscle (=0.30, =0.823) . The fitting line showed that the left erector spinae muscle showed a downward trend at 5°, 60 times/min (=-5.39, =0.012) . Scrapers are less likely to be fatigued when the posture is 15°, 30 times/min, but they are more likely to be fatigued when working at 5°, 60 times/min.
为模拟和评估不同脊柱前倾角工人的刮削和磨削工作，并探讨不同前倾角对刮削工人竖脊肌的影响。2019年11月，招募了16名男性大学生志愿者来模拟工人的刮削和磨削工作。参数分别为25°、每分钟15次，15°、每分钟30次，5°、每分钟60次。采用表面肌电图（sEMG）采集竖脊肌的肌电信号，并用Borg量表评估竖脊肌的表面肌电特征。不同脊柱前倾角的三组中，左右竖脊肌群的最大自主收缩百分比（MVE%）存在显著差异（（左侧）=13.41，（左侧）<0.001；（右侧）=4.74，（右侧）=0.005），且在25°、每分钟15次时肌电幅度更高。在15°、每分钟30次时，左侧的MVE%显著高于右侧（=2.58，=0.021）。三组中右侧竖脊肌的平均功率频率（MPF）存在显著差异（=9.42，<0.001），但左侧竖脊肌的MPF无显著差异（=0.30，=0.823）。拟合线显示，在5°、每分钟60次时左侧竖脊肌呈下降趋势（=-5.39，=0.012）。当姿势为15°、每分钟30次时，刮削工人疲劳的可能性较小，但在5°、每分钟60次工作时更容易疲劳。
