A survey done by the American Academy of Orthopedic Surgeons found 58% of its members had treated children with back and should pain caused by backpacks that are too heavy. During one study, a ten-year-old female was found with a backpack weighing 47 pounds. Some researchers say that heavy backpacks and improper use of backpacks cause pain not only in the back but also in the neck and shoulders for 75% of school aged children. A study by the medical journal Lancet found that about 35% of students carry of 30% of the body weight in the backpacks at least once a week. 67.2% of the children used as subjects in this study experienced muscle soreness. 50.8% suffered back pain. 14.7% felt shoulder pain. 24.5% suffered numbness. According to the American Academy of Orthopedic Surgeons, 21,208 children received treatment for back pain related to backpacks last year. According to estimates made by the U.S. Consumer Product Safety Commission, 12,206 injuries have occurred because of this backpack issue; 7,277 of these treated in emergency rooms. A study we performed in our own school found children with backpacks weighing up to 30 pounds. A teacher in our school had students list the contents of their backpacks to make sure they weren’t carrying any unnecessary items. 4th grade students were found carrying everything from rocks to a bathing suit!