There is variation regarding recommendations for children and adolescents carrying schoolbags. Guidelines for safe loads are mostly within 10%–15% of body weight (BW) range but include values as low as 5% and as high as 20%. Some biomechanical studies suggest that the schoolbag weight of 10% of BW may be enough to cause changes in kinematics, body posture and muscular strain.
Methods of Do Schoolbags Cause Low Back Pain?
This study performed a systematic search and retrieved 6597 studies. After removing duplicates and screening titles and abstracts, the researchers included 160 studies for full-text assessments; the researchers could not access the full-text for six of these studies and attempts to contact the authors were not successful. A total of 69 studies met our inclusion criteria and were included in this review (total n=72 627 participants). The researchers included four longitudinal cohort studies (n=1743), one RCT (n=108), 63 cross-sectional studies (n=70 720) and one case–control with retrospective data (n=56).
Two prospective studies (one longitudinal cohort and one RCT) evaluated associations between schoolbag weight (% BW) and risk of developing LBP; neither reported an association.
Two longitudinal studies evaluated ‘perception of schoolbag weight’ and risk of LBP. One study found that children with back pain who reported difficulty carrying their schoolbag had increased in risk of developing persistent LBP (RR 2.1, 95% CI 1.1 to 4.0). Another study also reported an association between the perception of schoolbag weight as heavy and LBP (OR 2.2, 95% CI 1.0 to 4.8). Based on the QUIPS rating for these two studies, we consider this low quality evidence for a relationship between perception of backpack weight and back pain.
Another longitudinal study did not investigate schoolbag weight or perception of weight; however, for the question on ‘pain provoking situations’, none of the participants mentioned that carrying the schoolbag provoked pain. None of the prospective longitudinal studies reported data on duration of using a schoolbag, episodes of care seeking for back pain or episodes of school absence due to back pain.
Twenty-eight studies investigated weight of schoolbag (% BW), ranging from 5% to 19% BW, and 29 studies investigated load carried, which ranged from 2 kg to 10 kg. Fourteen studies investigated duration of use of the schoolbag (ie, time carrying), ranging from 20 to 85 min per day. Regarding schoolbag design and method of carrying the bag, 22 studies reported that most students used backpacks or rucksacks (around 90%) and carried the schoolbag on both shoulders (around 75%), and a minority of students used satchels or shoulder bags carried on one shoulder or by hand.
Twenty-nine cross-sectional studies did not find an association between schoolbag characteristics and LBP. Four studies reported a positive association between the child’s perception of backpack weight and back pain. Three studies reported associations between the duration of carrying a back pack (prolonged periods) and back pain. Four studies reported associations between schoolbag weight (heavier) and back pain, and other three studies found an association between the method of carrying the schoolbags (one shoulder or asymmetrically) with back pain. For the retrospective case–control study, there were no data regarding the schoolbag weight or features, but 75% of the subjects with chronic non-specific LBP reported that carrying a schoolbag aggravated their pain.
Discussion of Do Schoolbags Cause Low Back Pain?
This systematic review provides evidence from prospective studies with moderate to high risk of bias that schoolbag characteristics such as weight, design and carriage method do not increase the risk of developing back pain in children and adolescents. Two prospective studies reported that the perception of heaviness or difficulty in carrying the schoolbag were associated with back pain and persistent symptoms. Evidence from cross-sectional studies supported the findings from prospective studies. Taken together, these results are not suggestive of a meaningful relationship between backpack use or weight and back pain in children and adolescents.
This study has limitations. We only found five prospective studies to include in this review. Since these studies investigated different variables and present results inconsistently, we were unable to pool results. Despite these limitations, the volume of research and the fact that associations show no consistent pattern suggest that any relationship between backpack use and back pain is minimal at best, and research resources aimed at understanding adolescent back pain are better directed elsewhere.
Schoolbag use does not appear to be an important risk factor for back pain in children and adolescents. However, due to the small number of prospective studies and low methodological quality of the studies included in this review, our findings should be interpreted with caution. There are few longitudinal cohort studies in children and adolescents in the literature, and in most of these cases identifying risk factors for back pain was not the primary aim. Consequently, the choice of exposure variables, measurement instruments and timing of data collection are not optimal to reveal causal relationships. These problems may explain why systematic reviews in this field do not have strong conclusions.
These findings call into question the various guidelines and statements that endorse specific weight limits for school bags in children and adolescents. It seems that these recommendations are not based on the most reliable evidence on the subject. The findings also have implications for the various professional bodies and clinicians that endorse or recommend specific backpacks. It is important that such endorsement is made on the basis of firm evidence and free of financial conflict.
Conclusion of Do Schoolbags Cause Low Back Pain?
Based on evidence from five longitudinal studies (n=1851 children and adolescents) and more than 60 cross-sectional studies, there is no convincing evidence that aspects of schoolbag use increase the risk of back pain. There is some evidence that the perception of heaviness is associated with back pain.
Many swim parents and coaches are concerned with the possible risk of heavy schoolbags and shoulder and/or low back stress. This systematic review suggests schoolbags do not increase the risk of back pain. However, more research is needed, as only 5 studies were deemed adequate for this review.
- Yamato TP, Maher CG, Traeger AC, Wiliams CM, Kamper SJ. Do schoolbags cause back pain in children and adolescents? A systematic review. Br J Sports Med. 2018 Oct;52(19):1241-1245. doi: 10.1136/bjsports-2017-098927. Epub 2018 May 2. Review.
Dr. John Mullen
DOCTOR OF PHYSICAL THERAPY
PERSONAL TRAINING WITH NATIONAL STRENGTH AND CONDITIONING ASSOCIATION
Dr. John Mullen, DPT, CSCS is a World renowned expert and speaker in sports training and rehabilitation. He received his Doctorate in Physical Therapy at USC, as well as the Josette Antonelli Division Service Scholarship, Order of the Golden Cane, and the Order of Areté. At USC, he also performed research on strength training and rehabilitation. Dr. John has worked with multiple professional and Olympic athletes, helping them earn Olympic medals.
His dedication to research and individualization spurred him to open COR in 2011. Since 2011, Dr. John has been featured in Gizmodo, Motherboard, Stack Magazine, and much more.
He has worked with the numerous colleges and teams regarding rehab and performance. Before his Doctoral program, Dr. John swam on an athletic scholarship at Purdue University.
At Purdue, Dr. John was an Academic Honorable Mention All-American and was awarded the Red Mackey Award and R. O. Papenguh Award. He also won the Purdue Undergraduate business plan and elevator pitch competition, as well as 1st prize with the Indiana Soy Bean Alliance.
Dr. John was born in Centerville, Ohio and was a 24-time high school All-American Swimmer. Dr. John is still a swimmer and holds a Masters Swimming World and Pacific Swimming Record.