Ramadan Mohamed Zaki, Alkahtani Mohammed
Department of Industrial Engineering, King Saud University, Riyadh, Saudi Arabia.
Raytheon Chair for Systems Engineering (RCSE Chair), Advanced Manufacturing Institute, King Saud University, Saudi Arabia.
Work. 2017;58(3):349-359. doi: 10.3233/WOR-172627.
Manual material handling (MMH) task is the most common cause of work-related musculoskeletal disorders (MSDs). Operators carrying unstable loads were recently shown to be at greater risk of back injury compared to workers carrying stable loads.
This study focused on developing a device to minimize trunk muscle activity and cardiovascular demand while handling a 19-liter bottle.
After evaluating several designs, one was selected to be developed, manufactured and tested through an experimental study. Healthy participants (n = 42) manually carried a 19-liter bottle. The carrying technique (i.e., carrying a lateral load while holding the load using the dominant hand, pulling the load using the developed device, carrying the load on the back using the developing device) was the independent variable. The muscular activities (e.g., neck extensor, upper trapezius, pectoralis major, deltoid medial, rectus abdominis, and erector spinae muscles of the dominant side), cardiac costs, plantar pressures, walking speeds, and subjective measures were the dependent variables.
Results show that carrying the developed device like a backpack significantly reduced trunk muscle activity, cardiovascular demand, and plantar pressure compared to the usual practice. The present results suggest that carrying a 19-liter water bottle using the developed device is likely to contribute to lower MSDs.
Implementation of the develop device recommended to lessen the risk of injury when handling unstable loads such as liquids.
手工搬运任务是与工作相关的肌肉骨骼疾病（MSD）的最常见原因。最近研究表明，与搬运稳定负载的工人相比，搬运不稳定负载的操作员背部受伤风险更大。
本研究专注于开发一种装置，在搬运19升瓶子时将躯干肌肉活动和心血管需求降至最低。
在评估了几种设计后，选择了一种进行开发、制造，并通过实验研究进行测试。健康参与者（n = 42）手动搬运一个19升的瓶子。搬运技术（即，用优势手握住负载搬运侧向负载、使用开发的装置拉动负载、使用开发的装置将负载背在背上）是自变量。肌肉活动（例如，优势侧的颈部伸肌、上斜方肌、胸大肌、三角肌内侧、腹直肌和竖脊肌）、心脏负荷、足底压力、步行速度和主观测量是因变量。
结果表明，与常规做法相比，像背背包一样携带开发的装置可显著降低躯干肌肉活动、心血管需求和足底压力。目前的结果表明，使用开发的装置搬运19升水瓶可能有助于降低肌肉骨骼疾病的风险。
建议使用开发的装置，以降低搬运诸如液体等不稳定负载时受伤的风险。
