Binkin, N, G Fontana, C Lamberti, et al. :A national survey of the prevalence of childhood overweight and obesity in Italy. .Obes Rev 11::2. ,2009. .
Wearing, SC, EM Hennig, NM Byrne, et al. :The impact of childhood obesity on musculoskeletal form. .Obes Rev 7::209. ,2006. .
McGraw, B, BA McClenaghan, HG Williams, et al. :Gait and postural stability in obese and nonobese prepubertal boys. .Arch Phys Med Rehabil 81::484. ,2000. .
Riddiford-Harland, DL, JR Steele, and LH Storlien. :Does obesity influence foot structure in prepubescent children? Int J Obes 24::541. ,2000. .
Dowling, AM, JR Steele, and LA Baur. :Does obesity influence foot structure and plantar pressure patterns in prepubescent children? Int J Obes 25::845. ,2001. .
Mickle, KJ, JR Steele, and BJ Munro. :Does excess mass affect plantar pressure in young children? Int J Pediatr Obes 1::183. ,2006. .
Villaroya, MA, JM Esquivel, C Tomas, et al. :Foot structure in overweight and obese children. .Int J Pediatr Obes 3::39. ,2004. .
Morrison, SC, BR Durward, GF Watt, et al. :Anthropometric foot structure of peripubescent children with excessive versus normal body mass. .JAPMA 97::366. ,2007. .
Mauch, M, S Grau, I Krauss, et al. :Foot morphology of normal, underweight and overweight children. .Int J Obes 32::1068. ,2008. .
Riddiford-Harland, DL, JR Steele, and LA Baur. :Are the feet of obese children fat or flat? revisiting the debate. .Int J Obes 35::115. ,2011. .
Dowling, AM, JR Steele, and LA Baur. :What are the effects of obesity in children on plantar pressure distributions? Int J Obes 28::1514. ,2004. .
Filippin, NT, T de Almeida Bacarin, and PH Lobo da Costa. :Comparison of static footprints and pedobarography in obese and non-obese children. .Foot Ankle Int 29::1141. ,2008. .
Filippin, NT, VLP Barbosa, ICN Sacco, et al. :Effects of obesity on plantar pressure distribution in children. .Rev Bras Fisioter 11::495. ,2007. .
Brackley, HM and JM Stevenson. :Are children’s backpack weight limits enough? a critical review of the relevant literature. .Spine 19::2184. ,2004. .
Skaggs, DL, SD Early, P D’Ambra, et al. :Back pain and backpacks in school children. .J Pediatr Orthop 26::358. ,2006. .
Pau, M and M Pau. :Postural sway modifications induced by backpack carriage in primary school children: a case study in Italy. .Ergonomics 53::872. ,2010. .
Pascoe, DD, DE Pascoe, YT Wang, et al. :Influence of carrying book bags in gait cycle and posture of youths. .Ergonomics 40::631. ,1997. .
Hong, Y and GP Brueggemann. :Changes in gait patterns in 10-year-old boys with increasing loads when walking on a treadmill. .Gait Posture 11::254. ,2000. .
Wearing, SC, EM Hennig, NM Byrne, et al. :Musculoskeletal disorders associated with obesity: a biomechanical perspective. .Obes Rev 7::239. ,2006. .
Cole, T, MC Bellizzi, KM Flegal, et al. :Establishing a standard definition for child overweight and obesity worldwide: international survey. .BMJ 320::1. ,2000. .
Cavanagh, PR and MM Rodgers. :The arch index: a useful measure from footprints. .J Biomech 20::547. ,1987. .
Hills, AP, EM Hennig, M McDonald, et al. :Plantar pressure differences between obese and non-obese adults: a biomechanical analysis. .Int J Obes 25::1674. ,2001. .
Cavanagh, PR, MM Rodgers, and A Iiboshi. :Pressure distribution under symptom free feet during barefoot standings. .Foot Ankle Int 7::262. ,1987. .
Sako, H, M Kawahara, and H Tanaka. :The effects of the load mass and load position on body sway in supporting a load on the back. .J Hum Ergol 33::55. ,2004. .
Demura, S, M Uchiyama, T Yamada, et al. :Effect of bag holding on the center of foot pressure and the lower leg muscle activities. .Eur J Sports Sci 5::89. ,2005. .
Goh, JH, K Thambyah, and K Bose. :Effects of varying backpack loads on peak forces in the lumbosacral spine during walking. .Clin Biomech (Bristol, Avon) 13( suppl 1:):S26.,1998. .
Singh, T and M Koh. :Effects of backpack load and position on spatiotemporal parameters and trunk forward lean. .Gait Posture 29::49. ,2009. .
Frey, C and J Zamora. :The effects of obesity on orthopedic foot and ankle pathology. .Foot Ankle Int 28::996. ,2007. .
Anandacoomarasamy, A, M Fransen, and L March. :Obesity and the musculoskeletal system. .Curr Opin Rheumatol 21::71. ,2009. .
Hue, O, M Simoneau, J Marcotte, et al. :Body weight is a strong predictor of postural stability. .Gait Posture 26::32. ,2007. .
Teasdale, N, O Hue, J Marcotte, et al. :Reducing weight increases postural stability in obese and morbid obese men. .Int J Obes 31::153. ,2007. .
Kellis, E . :Plantar pressure distribution during barefoot standing, walking and landing in preschool boys. .Gait Posture 14::92. ,2001. .
Among other adverse consequences, childhood obesity is known to influence foot structure and functionality. Yet little information is available regarding how the physiologic foot-ground interaction is altered when a localized load is carried, as occurs in the case of schoolbags. We investigated plantar contact area and pressure modifications induced by backpack carriage under actual conditions. We hypothesized that a localized load acting on the body would further increase the already excessive plantar pressure that exists with overweight and obese status.
Seventy overweight and obese schoolchildren aged 6 to 11 years underwent two 30-sec trials on a pressure platform during a regular school day, with and without a backpack. Total and subregion contact areas along with peak plantar pressures were obtained, and results were compared with those of an equal-numbered group of normal-weight schoolchildren.
Overweight and obese children generally had larger contact areas and higher peak plantar pressures compared with their normal-weight peers. In overweight and normal-weight participants, the backpack induced a similar generalized increase in contact area and pressures. However, the largest changes were observed in the forefoot, suggesting that load action tends to modify the physiologic pressure patterns.
Backpack carriage raises the already elevated peak plantar pressures in overweight children during upright stance and modifies the physiologic pressure patterns. Further investigations are needed to clarify the features of such phenomenon when dynamic activities are performed and to verify the existence of fatigue and overexertion on the foot as well as other possible negative long-term effects. (J Am Podiatr Med Assoc 103(4): 306–313, 2013)