The Effects of Ramp Gradients and Pushing–Pulling Techniques on Lumbar Spinal Load in Healthy Workers

Safety and Health at Work

Chutima Jalayondeja¹  Petcharatana Bhuanantanondh²  Wattana Jalayondeja³  Keerin Mekhora⁴  Chalearmpong Pinupong⁴ 

[1] Corresponding author. 999, Phuttamonthon 4, Road, Salaya, Nakhon Pathom, 73170, Thailand.;Ergonomics Society of Thailand (EST);Faculty of Allied Health Science, Thammasat University, Thailand;Faculty of Physical Therapy, Mahidol University, Thailand;

关键词: Manual handling;    Pulling;    Pushing;    Slope of ramp floor;    Spinal load;   

DOI  :  

来源: DOAJ

【 摘 要 】

Background: Many tasks in industrial and health care setting are involved with pushing and pulling tasks up or down on a ramp. An efficient method of moving cart which reduces the risk of low back pain should be concerned. This study aimed to investigate the effects of handling types (HTs) and slope on lumbar spinal load during moving a cart on a ramp. We conducted a 2 × 2 × 4 factorial design with three main factors: 2 HTs, 2 handling directions of moving a cart and 4 degrees of ramp slope. Methods: Thirty healthy male workers performed 14 tasks consist of moving a cart up and down on the ramp of 0°, 10°, 15°, and 20° degrees with pushing and pulling methods. Joint angles from a 3D motion capture system combined with subject height, body weight, and hand forces were used to calculate the spinal load by the 3DSSPP program. Results: Our results showed significant effect of HT, handling directions and slope on compression and shear force of the lumbar spine (p < 0.001). When the ramp gradient increased, the L4/5 compression forces increased in both pushing and pulling (p < 0.001) Shear forces increased in pulling and decreased in pushing in all tasks. At high slopes, pulling generated more compression and shear forces than that of pushing (p < 0.01). Conclusion: Using the appropriate technique of moving a cart on the ramp can reduce the risk of high spinal load, and the pushing is therefore recommended for moving a cart up/down on ramp gradients.

【 授权许可】

Unknown