Acute stress and strain due to backpack loading among primary school pupils.

Abstract

Schoolbag carriage represents a considerable daily occupational load for children (Negrini et al., 1999). Whittfield et al., (2001) and Puckree et al., (2004) have reported that the carriage of heavy schoolbags is a suspected aetiological factor of the daily physical stress of school pupils. Methods: One hundred and eighty-seven pupils voluntarily participated in a controlled, descriptive, epidemiological retrospective study. Subjects’ biographical, epidemiological, exercise history and lifestyle information was gathered by a self-report questionnaire (adapted from Puckree et al., 2004). Subjects’ body mass, stature and mass of their schoolbags were measured using a Detecto stadiometer scale. Digital images, electromyographical muscular activity and a posture profile assessments were captured in the frontal and sagittal planes whilst the pupils were in the loaded (carrying a schoolbag) and the unloaded phases (not carrying schoolbags). These images were analyzed using biomechanical software, Dartfish. The study being retrospective in nature recorded the prevalence of schoolbag carriage musculoskeletal pain over the last 12 months. Descriptive statistical tests such as mean, mode, frequency, percentages and inferential chi-square statistical test (set at a probability of 0.05) were employed to analyze the data. Results: The result indicated that 78.99% of the cohort experience musculoskeletal pain due to schoolbag carriage (p<0.0001). The most prevalent anatomical sites of pain were the shoulders (37.04%), neck (20.37%), lumbar (11.73%) and thorax (10.49%) (p<0.0001). The mean mass of the schoolbag carried by the cohort was 5.45kg which was approximately 11.5% of their body mass. The predisposing factors of the musculoskeletal pain were the methods employed to carry the schoolbag (single strap (20.21%) versus double straps (76.6%), altered posture due to excessive schoolbag mass together with a reduced craniovertebral angle (p<0.05). Discussion & Conclusion: The excessive schoolbag mass carried by the pupils placed strain on the immature vertebral column of these pupils thus causing postural deviations which induced musculoskeletal pain and discomfort.