Effects of laptop bag carrying styles on joint dynamics

Abstract

With increased mobility, people carry laptops as part of their daily routine. Based on personal preference, they are held as handbags, shoulder bags, or cross-body bags. However, regardless of the carry style, their unilateral nature can affect skeletal health and cause discomfort, potentially leading to long-term injuries and high societal costs. This study examines the effects of carrying styles on joint movements. Twenty-five participants aged 21 to 24 walked on a treadmill under four conditions: without a laptop; while holding a 5 kg laptop case as a handbag in the dominant hand; as a shoulder bag hanging on their dominant side; and as a cross-body bag worn on their dominant side. Joint motions were recorded. Range of motion (ROM) and average angles (RMS values) of the joints were measured in the sagittal, frontal, and transverse planes. Kinematic analysis revealed that spinal joint movements were restricted under load, and these restrictions were asymmetric between the right and left sides (p<0.05). The reduction in ROM was highest with the handbag carrying style, the shoulder bag style showed the highest asymmetry, and the cross-body style had the least impact on joint movements. By demonstrating the effects of load carrying on joints, this study may help clinicians design strategies to mitigate unilateral load-related risks and reduce injuries.

Keywords

• Joint kinematics
• gait analysis
• laptop carrying styles
• range of motion
• unilateral load

References

1. Abaraogu, U. O., Duru, D. O., Imaji, B., Ezenwankwo, E. F., & Fawole, H. (2020). Musculoskeletal problems and backpack carriage among students in Nigeria. Work, 65(1), 175-180.
2. Alamoudi, M., Travascio, F., Onar-Thomas, A., Eltoukhy, M., & Asfour, S. (2018). The effects of different carrying methods on locomotion stability, gait spatio-temporal parameters and spinal stresses. International Journal of Industrial Ergonomics, 67, 81-88.
3. Altman, D. G. (1990). Practical statistics for medical research. Chapman & Hall/CRC.
4. Anyachukwu, C. C., Chilaka, P. C., Amarah, C. C., Daniel, J. A., Ezeaguba, G. C., & Ajare, E. C. (2024). The Impact of Ergonomics on Lower Back Pain Among Students Engaged in Prolonged Sitting Activities in University of Nigeria Enugu Campus. Journal of Biomedical Investigation, 12(2), 226-235.
5. Buisseret, F., Draye, N., Di Santo, C., Pacewicz, J., Pannetier, J., Dierick, F., & Telliez, F. (2024). Occupational risk factors for musculoskeletal disorders among workers in dairy diversification. Healthcare, 12(2), Article 178.
6. Chen, Y. L., Nguyen, H. T., & Chen, Y. (2021). Influence of school bag loads and carrying methods on body strain among young male students. International Journal of Industrial Ergonomics, 82, 103095.
7. Delsys. (2024). Delsys Wireless Biofeedback System Delsys Incorporated. https://www.delsys.com.
8. Dijksma, C. I., Bekkers, M., Spek, B., Lucas, C., & Stuiver, M. (2020). Epidemiology and financial burden of musculoskeletal injuries as the leading health problem in the military. Military Medicine, 185(3-4), e480-e486.

9. Fatoye, F., Gebrye, T., Ryan, C. G., Useh, U., & Mbada, C. (2023a). Global and regional estimates of clinical and economic burden of low back pain in high-income countries: A systematic review and meta-analysis. Frontiers in Public Health, 11, 1098100.
10. Fatoye, F., Gebrye, T., Mbada, C. E., & Useh, U. (2023b). Clinical and economic burden of low back pain in low- and middle-income countries: A systematic review. BMJ Open, 13(4), e064119.
11. Fox, B. D., Judge, L. W., Dickin, D. C., & Wang, H. (2020). Biomechanics of military load carriage and resulting musculoskeletal injury: A review. Journal of Orthopedics and Orthopedic Surgery, 1(1).
12. Greggi, C., Visconti, V. V., Albanese, M., Gasperini, B., Chiavoghilefu, A., Prezioso, C., … Tarantino, U. (2024). Work-related musculoskeletal disorders: A systematic review and meta-analysis. Journal of Clinical Medicine, 13(13), 3964.
13. Hollander, M., Wolfe, D. A., & Chicken, E. (2013). Nonparametric statistical methods (3rd ed.). John Wiley & Sons.
14. Kalichman, L., & Hunter, D. J. (2007). Lumbar facet joint osteoarthritis: A review. Seminars in Arthritis and Rheumatism, 37(2), 69-80.
15. Knapik, J. J., Reynolds, K. L., & Harman, E. (2004). Soldier load carriage: Historical, physiological, biomechanical, and medical aspects. Military Medicine, 169(1), 45-56.
16. Mandrekar, S., Chavhan, D., Shyam, A. K., & Sancheti, P. K. (2022). Effects of carrying school bags on cervical and shoulder posture in static and dynamic conditions in adolescent students. International Journal of Adolescent Medicine and Health, 34(1), 20190073.
17. MathWorks. (2024). MATLAB (Version 24.2.0.2740171, R2024b Update 1) [Computer software]. https://www.mathworks.com.
18. Matur, F., Alnamroush, F., & Büyüksaraç, B. (2025). Impact of backpack load during walking: An EMG and biomechanical analysis. Medical & Biological Engineering & Computing, 1-7.
19. Rodrigues, B. K. M. M., Maciel, M. A. M., Parente, B. L., de Paula Lima, P. O., & Abdon, A. P. V. (2020). Use and weight of shoulder bag in female gait. Motricidade, 16(2), 144-155.
20. Silva, J. J., Batistela, R. A., Goncalves, C. T., Rinaldi, N. M., & Moraes, R. (2020). Stability control in older adults with asymmetrical load carrying when stepping down a curb. Journal of Biomechanics, 106, 109840.
21. Sotiropoulos, S., Papandreou, M., Mavrogenis, A., Tsaroucha, A., & Georgoudis, G. (2025). The effects of Qigong and Tai Chi exercises on chronic low back pain in adults: A systematic review and meta-analysis of randomized controlled trials. Cureus, 17(5).
22. Tankha, H., Gaskins, D., Shallcross, A., Rothberg, M., Hu, B., Guo, N., ... & Saper, R. (2024). Effectiveness of virtual yoga for chronic low back Pain: a Randomized Clinical Trial. JAMA Network Open, 7(11), e2442339-e2442339.Xsens mvn user manual. Xsens Motion Technologies BV: Enschede, The Netherlands (2015). https://do.org/10.1001/jamanetworkopen.2024.42339
23. Wang, J., & Gillette, J. (2017). Carrying asymmetric loads during stair negotiation. Gait & Posture, 53, 67-72.
24. Wang, J., Stephenson, M. L., Hass, C. J., Janelle, C. M., & Tillman, M. D. (2021). Carrying asymmetric loads while walking on a treadmill interferes with lower limb coordination. International Journal of Environmental Research and Public Health, 18(9), 4549.
25. Wareham, D. M., Fuller, J. T., Douglas, T. J., Han, C. S., & Hancock, M. J. (2024). Swimming for low back pain: A scoping review. Musculoskeletal Science and Practice, 71, 102926.
26. Yadav, V., Gudavalli, M. R., Raju, P. K., & Marghitu, D. (2014, November). Biomechanics of trunk during walking carrying load on one hand using nonlinear methods. In ASME International Mechanical Engineering Congress and Exposition (Vol. 46469, p. V003T03A022). American Society of Mechanical Engineers.
27. Zagrodny, B., Ludwicki, M., & Wojnicz, W. (2021). The influence of external additional loading on the muscle activity and ground reaction forces during gait. Applied Bionics and Biomechanics, 2021(1), 5532012.
28. Zhang, X. A., Ye, M., & Wang, C. T. (2010). Effect of unilateral load carriage on postures and gait symmetry in ground reaction force during walking. Computer Methods in Biomechanics and Biomedical Engineering, 13(3), 339-344.
29. Zhao, G., Wang, H., Wang, L., Ibrahim, Y., Wan, Y., Sun, J., … Liu, X. (2023). The biomechanical effects of different bag-carrying styles on lumbar spine and paraspinal muscles: A combined musculoskeletal and finite element study. Orthopaedic Surgery, 15(1), 315-327.