Backpacks, back pain, sagittal spinal curves and trunk alignment in adolescents: a logistic and multinomial logistic analysis.

STUDY
DESIGN: Cross-sectional study using logistic and multinomial logistic analysis.
OBJECTIVES: To investigate the influence of backpack carrying on spinal profile shoulder and trunk. SUMMARY OF BACKGROUND DATA: No similar investigations.
METHODS: A randomly selected sample of 1263 students aged 12-18 years were asked for dorsal (DP) and low back pain (LBP) during the school period and holidays. Debrunner's Kyphometer and Scoliometer were used to measure craniocervical angle (CCA), thoracic kyphosis, lumbar lordosis, and shoulder shift (BL). Upper trunk shift from plumbline were recorded.
RESULTS: Girls suffer from DP more often and of much more intensity pain than boys in school period and in holidays. Backpack carrying decreased CCA and changed shoulder and upper trunk shift. Asymmetrically backpack carrying increased DP and LBP. BL-shift increased DP. DP and LBP increased with coronal trunk shift. Sagittal trunk shift increased LBP. Asymmetrically carrying of backpacks increased back pain and shoulder shift in holidays. Coronal trunk shift while carrying backpacks asymmetrically increased back pain in holidays. Asymmetric backpack carrying is associated with high intensity pain. Frontal trunk shift is associated with high intensity pain.
CONCLUSION: Backpack carrying, particularly asymmetrically, results in shift of upper trunk and shoulder and cervical lordosis, which furthermore seem to increase back pain in school period and holidays. Symmetric backpack carrying is recommended.