title: Effect of asymmetrical backpack load on spinal curvature in school children.
abstract: BACKGROUND
  Carrying a backpack is common among schoolchildren. The effect of backpack load on spine pain and posture defects in children is often raised in the literature. According to scientific research, the maximum backpack load that is safe for children must not exceed 10-15% of their body mass. There is a lack of scientific reports related to the effect of frequently wearing a backpack on one shoulder among children and young adults and its influence on the shape of the anterior-posterior curvatures of spine.
  
  
  OBJECTIVE
  The aim of this study is to evaluate body posture parameters in the sagittal plane for an asymmetrical backpack load equal to 10% of a child's body mass.
  
  
  METHODS
  The study was conducted using 162 primary schoolchildren aged 11-13 years. Each participant underwent three tests that examined postural parameters, including habitual posture, with the backpack on the participant's right and left shoulder. Posture was measured with the CQ Elektronik; which uses photogrammetry to make anthropometric calculations based on an image of the examined surface.
  
  
  RESULTS
  The asymmetrical backpack load resulted in a significant reduction of thoracic kyphosis (GKP: p=0.040). The angle of thoracic kyphosis increased between the measurements. The difference (GAMMA=0.054) revealed that the results were approaching significance.
  
  
  CONCLUSIONS
  Considering the gravity of the problem, children should be educated on ergonomics by teachers, physiotherapist or nurses, including instructions on carrying a backpack and the effects of disregarding the basic rules on body posture, as part of their school curriculum. The acceptable backpack load, which is now believed to be 10% of the child's body mass, should be carefully considered by scientists. Our own results show that even a load of 10% of the body mass may induce negative changes in spinal posture.
authors.affiliation: Institute of Physiotherapy, University of Rzeszów, Rzeszów, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Drzał-Grabiec
authors.affiliation: Faculty of Rehabilitation, Józef Piƚsudski University of Physical Education in Warsaw, Warsaw, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Truszczyńska
authors.affiliation: Institute of Physiotherapy, University of Rzeszów, Rzeszów, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Rykała
authors.affiliation: Institute of Physiotherapy, University of Rzeszów, Rzeszów, Poland.
authors.forename: Maciej
authors.initials: M
authors.lastname: Rachwał
authors.affiliation: Institute of Physiotherapy, University of Rzeszów, Rzeszów, Poland.
authors.forename: Sławomir
authors.initials: S
authors.lastname: Snela
authors.affiliation: Institute of Physiotherapy, University of Rzeszów, Rzeszów, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Podgórska
mesh_terms: D000293:Adolescent; D001696:Biomechanical Phenomena; D002648:Child; D005260:Female; D006801:Humans; D007738:Kyphosis / Q000517:prevention & control*; D008297:Male; D011187:Posture / Q000502:physiology*; D013131:Spine / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology*
keywords: Spinal load; asymmetric loading; back pain; children