Adeyemi Ademola James, Rohani Jafri Mohd, Rani Mat Rebi Abdul
Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, Johor, Malaysia.
Department of Mechanical Engineering, College of Engineering, W.U. Federal Polytechnic, Birnin Kebbi, Kebbi State, Nigeria.
Work. 2015;52(3):677-86. doi: 10.3233/WOR-152102.
The complex and limited understanding of the interactions among multiple factors associated with back pain occurrence among schoolchildren might explain the current inconclusive and contradictory findings on the issue. The global increase in the prevalence of childhood overweight and obesity, which reportedly affects children's physical abilities, calls for concern among school/children ergonomists and other stakeholders.
The study investigated the interaction of body mass index (BMI) and age on the muscular activities, backpack height and perceived level of pain arising from carrying different weight of backpacks.
Surface electromyography analysis of erector spinae and trapezius muscular activities was conducted on 47 primary schoolchildren aged between 8 and 11 years. Repeated measure ANOVA were carried out on the data.
There was significant difference in all the measures of muscular activities, backpack height and pain rating at different levels of backpack weight. However, the children were only significantly fatigable in the erector spinae muscles of the lower back and not in the trapezius of the upper back. The interactive effect of BMI was more pronounced than the children's age.
The study shows that it is not appropriate for all schoolchildren to have the same backpack weight limit and obese schoolchildren should carry a lower bag-to-body ratio of backpack weight. The younger children also need an appropriate bag surface-to-trunk ratio size of backpack as they were more affected by the position of the backpack.
对学童背痛发生相关多种因素之间相互作用的复杂且有限的理解，可能解释了目前关于该问题尚无定论且相互矛盾的研究结果。据报道，全球儿童超重和肥胖患病率上升，这会影响儿童的身体能力，引起了学校/儿童人体工程学专家及其他利益相关者的关注。
本研究调查了体重指数（BMI）和年龄对携带不同重量背包时肌肉活动、背包高度及疼痛感知水平的相互作用。
对47名8至11岁的小学生进行了竖脊肌和斜方肌肌肉活动的表面肌电图分析。对数据进行重复测量方差分析。
在不同背包重量水平下，肌肉活动、背包高度和疼痛评分的所有测量指标均存在显著差异。然而，儿童仅在下背部的竖脊肌出现明显疲劳，而上背部的斜方肌未出现。BMI的交互作用比儿童年龄更为显著。
该研究表明，对所有学童设定相同的背包重量限制是不合适的，肥胖学童应携带背包重量与身体比例更低的背包。年幼的儿童也需要合适的背包表面积与躯干比例尺寸，因为他们受背包位置的影响更大。
