To investigate the use and protective effect of helmets in children injured in bicycle crashes and changes in injury patterns during a period of increased helmet use.
Injuries in 4246 children below 16 years of age, who attended an A&E ward after a bicycle crash in the Gothenburg region during 1993-2006, were analyzed. The injury severity was classified according to the Abbreviated Injury Scale. The occurrence of skull/brain injuries and facial injuries was analyzed for 3711 children with respect to injury severity, helmet use and demographic and crash-related factors. Changes in injury patterns during the period were analyzed for 4246 children with no regard to helmet use. The ratio of the number of subjects with head injuries to the number of subjects with extremity injuries of any severity and of at least moderate severity was used to estimate the protective effect of helmet at a population level.
Helmets were used by 40% of the injured children at the beginning of the period and by 80% at the end; much less frequently by teenagers, especially girls. The adjusted odds of serious or more severe skull/brain injuries and moderate or more severe facial injuries with a helmet were about one fourth of those without a helmet. The proportion of children with skull/brain injuries did not change significantly during the period. Serious or more severe skull/brain injuries were noted more often during the latter half of the period, most often in children without a helmet. The proportion of children with facial injuries decreased, and the proportion with injuries to the upper extremities increased, also for moderate and severe injuries. The ratio between the number of children with head injuries and the number with extremity injuries decreased for injuries of any severity and for moderate or more severe injuries.
Bicycle helmets have an obvious protective effect against head injuries in children, regardless of the crash circumstances. Teenagers must be informed about the high risk of skull/brain injuries in bicycle crashes without a helmet. The increasing occurrence of injuries to the upper extremities needs attention.