Department of Rehabilitation Medicine, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands.
Department Rehabilitation Technology, Roessingh Research and Development, Roessinghsbleekweg 33b, 7522 AH Enschede, The Netherlands.
Sensors (Basel). 2021 Apr 2;21(7):2476. doi: 10.3390/s21072476.
A sensor-based system using inertial magnetic measurement units and surface electromyography is suitable for objectively and automatically monitoring the lumbar load during physically demanding work. The validity and usability of this system in the uncontrolled real-life working environment of physically active workers are still unknown. The objective of this study was to test the discriminant validity of an artificial neural network-based method for load assessment during actual work. Nine physically active workers performed work-related tasks while wearing the sensor system. The main measure representing lumbar load was the net moment around the L5/S1 intervertebral body, estimated using a method that was based on artificial neural network and perceived workload. The mean differences (MDs) were tested using a paired -test. During heavy tasks, the net moment (MD = 64.3 ± 13.5%, = 0.028) and the perceived workload (MD = 5.1 ± 2.1, < 0.001) observed were significantly higher than during the light tasks. The lumbar load had significantly higher variances during the dynamic tasks (MD = 33.5 ± 36.8%, = 0.026) and the perceived workload was significantly higher (MD = 2.2 ± 1.5, = 0.002) than during static tasks. It was concluded that the validity of this sensor-based system was supported because the differences in the lumbar load were consistent with the perceived intensity levels and character of the work tasks.
基于惯性磁测量单元和表面肌电图的传感器系统适用于客观、自动地监测体力劳动过程中的腰椎负荷。然而，该系统在体力活动工人不受控制的实际工作环境中的有效性和可用性尚不清楚。本研究的目的是测试基于人工神经网络的负荷评估方法在实际工作中的判别有效性。9 名体力活动工人在佩戴传感器系统的情况下完成了与工作相关的任务。腰椎负荷的主要衡量标准是基于人工神经网络和感知工作负荷的 L5/S1 椎间体周围的净力矩。使用配对检验测试均值差异（MD）。在重任务中，观察到的净力矩（MD=64.3±13.5%，=0.028）和感知工作负荷（MD=5.1±2.1，<0.001）明显高于轻任务。动态任务的腰椎负荷方差明显更高（MD=33.5±36.8%，=0.026），感知工作负荷也明显更高（MD=2.2±1.5，=0.002）。综上所述，该基于传感器系统的有效性得到了支持，因为腰椎负荷的差异与工作任务的感知强度水平和特征一致。
