Abaraogu Ukachukwu O, Ezenwankwo Elochukwu F, Nwadilibe Ijeoma B, Nwafor Geoffrey C, Ugwuele Bianca O, Uzoh Pascal C, Ani Ifunanya, Amarachineke Kinsley, Atuma Collins, Ewelunta Obed
Work. 2017;57(1):87-93. doi: 10.3233/WOR-172531.
Heavy backpacks have been associated with various postural changes and consequently musculoskeletal disorders.
We evaluated the immediate responses of varying backpack loads on cranio-vertebral angle (CVA), sagittal shoulder angle (SSA) and trunk forward lean (TFL) of young adults between the ages of 18-25 years.
This was a 3×3 cross over randomized controlled study with repeated measures among a convenience sample of young adults (n = 30; 50% male, 50% female). Each participant in a standing posture was assessed at four different loads: no backpack, carrying backpack of 5%, 10%, and 15% of body weight (BW). A sagittal photograph was taken of the area of the body corresponding to spinal angle during each of these test conditions to allow for later analysis of postural deviations. Comparisons of the mean deviations of the different postural angles from baseline and between test conditions were made using ANOVA at p≤0.05.
Generally, there was a trend toward a decrease in the CVA and TFL with increasing backpack loads. Specifically, a significant decrease was seen for TFL at10% and 15% BW loads when compared with no load condition. In contrast, the decrease in CVA was only significant between no load condition and 15% body weight load. The SSA remained unchanged with backpack weight within 15% BW.
Whereas the SSA of young adults may not be upset by an acute loading with a backpack within 15% of body weight, a 15% BW backpack led to more forward posture of the head on the neck. In addition, backpack load as low as 10% BW is enough to cause an immediate forward lean of the trunk.
沉重的背包与各种姿势变化相关，进而导致肌肉骨骼疾病。
我们评估了不同背包负荷对18至25岁年轻人的颅椎角（CVA）、矢状肩角（SSA）和躯干前倾（TFL）的即时反应。
这是一项3×3交叉随机对照研究，对一组方便样本的年轻人（n = 30；50%为男性，50%为女性）进行重复测量。让每个参与者以站立姿势在四种不同负荷下接受评估：不背背包、背负体重5%、10%和15%的背包。在每种测试条件下，拍摄身体对应脊柱角度区域的矢状面照片，以便稍后分析姿势偏差。使用方差分析（ANOVA）对不同姿势角度相对于基线以及不同测试条件之间的平均偏差进行比较，p≤0.05。
一般来说，随着背包负荷增加，CVA和TFL有下降趋势。具体而言，与无负荷状态相比，在10%和15%体重负荷下TFL有显著下降。相比之下，CVA的下降仅在无负荷状态和15%体重负荷之间显著。在体重的15%以内，SSA随背包重量保持不变。
虽然体重15%以内的背包急性负荷可能不会扰乱年轻人的SSA，但15%体重的背包会导致头部在颈部的姿势更加前倾。此外，低至10%体重的背包负荷就足以导致躯干立即前倾。
