Background: Carrying the school bag may lead to forward leaning of the head and trunk which may result in spinal deformities.
Objective: The purpose of this study was to evaluate the effect of carrying a backpack on neck angles and ground reaction forces (GRFs) in children.
Methods: 3-D motion analysis system, with a force plate, was used to examine the effect of carrying backpack on neck angles and GRFs of thirty children with mean age (10.06 ± 1.31 years), mean weight (34.56 ± 6.9 kg), and mean height (138.63 ± 9.82 cm). The unloaded posture was compared with posture when carrying a backpack. The static test was used to assess the three angles of the neck, and the dynamic test was used to assess the GRFs.
Results: There were no significant differences in the craniohorizontal angle and shoulder sagittal posture between carrying backpack and without backpack (p = 0.153 and 0.272) respectively. There was a significant decrease in the craniovertebral angle in carrying backpack than without backpack (p = 0.032). There was a significant increase in GRFs values in carrying backpack than without backpack (p < 0.032).
Conclusion: Carrying backpack with a load 7.5% of the child's body weight alters the head posture and GRFs values.
Keywords: Children; ground reaction forces; load carriage; neck angles.