Poster Q7 - Functional Assessment of an Ergonomic Backpack Compared to a Traditional Backpack During Walking

Introduction: Backpacks (BP) are the most common means for carrying items by individuals of all ages. However, modern day two strap backpack create problematic loading conditions at the shoulders and lower back that increase the risk of injury due to the excessive load being carried.1-7 A prototype Ergonomic Backpack (EBP) was designed to reduce these complications and improve load carriage performance (Fig. 1). The purpose of this study was to determine the effects of wearing the EBP during level walking compared to a traditional two strap BP.

Materials and

Methods: Fifteen participants walked on an instrumented treadmill wearing the EBP and traditional BP. Body segment kinematics and ground reaction force data were used to determine trunk angle and muscle powers at each major joint (Fig. 2). Electromyography signals were processed and used to determine the muscle activation. Indirect calorimetry measured oxygen consumption during ten-minute walking trials under two load carrying conditions (7 kg and 11 kg).

Results, Conclusions, and Discussions:

Results: The EPB maintained significantly more vertical trunk orientation (Fig. 3A), lower paraspinal muscle activity, and decreased hip muscle power with the EBP (Fig. 3B) compared to the traditional backpack (p < 0.05) for both load conditions. Additionally, comfort scores were significantly reduced while wearing the EBP compared to the traditional BP (Fig. 3C).

Conclusions: This functional assessment provided evidence of the efficacy of the EBP to improve ergonomic performance and potentially reduce the risk of shoulder and lower back musculoskeletal injuries.

References
1. Genitrini M, et al. (2022) Impact of Backpacks on Ergonomics: Biomechanical and Physiological Effects: A Narrative Review. Int J Environ Res Public Health. 19(11):6737. doi: 10.3390/ijerph19116737.
2. Barbosa, J. et al. (2021) Impact of Overloaded School Backpack: An Emerging Problem. The Open Sports Sciences Journal. 14:76-81. DOI: 10.2174/1875399X02114010076.
3. Toghroli, R., et al. (2021). Backpack improper use causes musculoskeletal injuries in adolescents: A systematic review. Journal of education and health promotion, 10, 237. https://doi.org/10.4103/jehp.jehp_306_20
4. Rodriguez-Soto, AE et al. (2013). Effect of Load Carriage on Lumbar Spine Mechanics. Spine, Vol. 38(13): pp. 83-91.
5. Vacheron, JJ et al. (1998) Changes on Contour of the Spine Caused by Load Carrying”, Surgical and Radiologic Anatomy, Vol. 21(2):pp. 109-113.
6. Harman et al. (2000) The Effects of Backpack Weight on the Biomechanics of Load Carriage. Military Performance Division.
7. Santos, P., et al. (2023). Modular Backpack Project for Children – An Ergodesign Approach. Advances in Design, Music and Arts II 25, 502-513. https://doi.org/10.1007/978-3-031-09659-4_37.

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