Reality and risk of contact-type head injuries related to bicycle-mounted child seats.
OBJECTIVE
The authors have treated numerous children who have been injured by falling from bicycle-mounted child seats. Despite the greatly increased use of such seats, the understanding of their risk and the importance of helmet use remains alarmingly poor. The objective of this study was to confirm the risk of bicycle-mounted child seats and to evaluate the efficacy of helmets, seat belts, and back seat height in terms of preventing or mitigating contact-type head impacts that occur in falls from bicycle-mounted child seats.


METHODS
Biometrical dummy tests were performed to examine contact-type head injuries in falls from stationary bicycles. A bicycle with an anthropometric test dummy placed in a bicycle-mounted child seat was tipped over. Each test was repeated three times and three-dimensional acceleration was measured using accelerometer. Head Injury Criteria (HIC) were calculated and the respective influences of a helmet, a seat belt, and increased height of the back of the seat on such impacts were evaluated.


RESULTS
Only helmets unequivocally lowered maximal acceleration and/or HIC values with statistical significance. The seat belt lowered HIC values as long as it was used with the high-back seat. Only when the dummy wore a helmet sitting in a high-back seat did the HIC show less than the threshold of 570 for three-year-old children. The HIC showed the lowest score of 161.5 when the dummy wore both a helmet and a seat belt sitting in a high-back seat.


CONCLUSIONS
Riders in bicycle-mounted child seats definitely have higher risks of contact-type head injuries. In transporting a child on a bicycle-mounted child seat, parents must use both a child-bicycle helmet and a high-back child seat at least; a seat belt is highly recommended as long as it is used with the other safety devices.


CONCLUSIONS
The bicycle-mounted child seat should have a high enough back and an appropriate seat belt to protect the head of the child from a contact-type injury.
Department of Neurosurgery, Graduate School of Medicine, The University of Tokyo, Japan. shinya-miyamoto@ouhsc.edu
Shinya
S
Miyamoto
Shigenori
S
Inoue
D001642:Bicycling / Q000293:injuries*; D057207:Child Restraint Systems; D002675:Child, Preschool; D004867:Equipment Design; D004869:Equipment Safety; D016489:Head Injuries, Closed / Q000145:classification / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D018570:Risk Assessment