To Determine the Efficacy of Addition of Horizontal Waist Strap to the Traditional Double Shoulder Strap School Backpack Loading on Cervical and Shoulder Posture in Indian School going Children

Abstract

Study Design: Experimental same subject design. Objective: To determine the efficacy of addition of horizontal waist strap to the traditional double shoulder strap school bag on cervical and shoulder posture in Indian school going children. Methods: A total of 60 school children aged 10-16 years were randomly selected from CBSE affiliated schools in Delhi, which participated in this study. Each child’s body weight, height, and school bag weight were measured. Posture was measured in the form of three angles: (1) CVA, (2) CHA, (3) SSP, from the sagittal plane and recorded photographically under two different types of backpacks: (1) Double Shoulder Strap Backpack and, (2) Additional Waist Strap Backpack, each backpack had three conditions: (1) unloaded 0% body weight, (2) Static with 10% body weight, (3) post dynamic with 10% body weight. Data analysis: Comparison of postural angles was done between the two types of backpacks and between the three types of loading conditions. The significance of changes in data for the loading conditions was estimated using repeated measure analysis of variance on each angle with which planned contrast were made of the unloaded condition with each of two other loaded condition. The significance of changes in data for the two types of backpacks was estimated using paired t-test on each angle with which planned contrast were made of similar loading conditions between the backpacks. Statistical test were considered significant if p=0.05. Results: The changes in the postural angles with backpack loading were found to be less significant in backpack with additional waist strap as compared to double shoulder strap backpack. A significant change in postural angle was found in 2 loading conditions, static loading (10% BW) and dynamic loading (10% BW) when comparing with unloaded condition. Results revealed that using a backpack with additional waist strap to a traditional double shoulder strap backpack can bring significantly less changes in cervical and shoulder posture. Conclusion: The results of the study suggests that addition of horizontal waist strap to the traditional double shoulder strap backpack loading with 10% body weight reduces the changes in cervical and shoulder postures as compared with the traditional double shoulder strap backpack loading with 10% body weight.