A Multicentre Observational Case-controlled Feasibility Study: In Children Who Ride Bikes or Scooters, is the Risk of Sustaining a Serious Injury Greater When Metal Handlebar Ends Are Exposed Than When They Are Covered by Intact Grips?

Injuries are the most common cause of death of children aged 1-14 years in the European Union[11]. In the United States cyclist injuries are the 3rd most common mechanism of injury in 7-13 year olds, after motor vehicle collisions (MVC) and falls[1]. Bicycle injuries have remained one of the most common causes of paediatric abdominal trauma for over 60 years[2,3]. The vast majority (95-98%) of child cyclists admitted due to abdominal trauma are over 5 years old[2,3]. As with most mechanisms of injury, boys are injured more frequently than girls. Around three quarters of injured child cyclists are boys[12].

In a recent UK study, handlebar end impact was the mechanism that most frequently resulted in major intra-abdominal trauma in children. Impact with a handlebar end was implicated in 29% of cases. This was ahead of falls (20%), pedestrians (8%) and MVC occupants (8%)[3]. A study conducted in Australia found 15% of child cyclist injuries involved impact with a handlebar, and 10% of all child cyclist injuries were abdominal handlebar injuries[4]. A study in Philadelphia found that 8% of all paediatric bicycle-related trauma admissions involved handlebars impacting the abdomen resulting in an injury with an Abbreviated Injury Scale (AIS) score of 2 or greater[13].

The majority of handlebar injury case series reported in the literature relate to children's abdominal injuries. The peak incidence occurs between 6 and 14 years of age[4]. However, adults can also sustain serious handlebar related injuries[14-16] and 36% of all handlebar injured patients sustain only extra-abdominal injuries[4]. It is not just pedal cyclists who are at risk of these injuries. Incidents also involve non-motorized kick scooters, moto-cross bikes, motorbikes and quad bikes[3,4].

Crash investigations have found that serious handlebar injuries often occur after apparently minor incidents; they are not unique to riders performing stunts or those riding BMX bikes[5,6]. There is a typical sequence of events common to many of these handlebar injuries[5]. The child loses control of the bike and begins to fall. The front wheel rotates through 90 degrees so that it is perpendicular to the child's body. The child continues to fall forwards, landing on the upturned handlebar end.

Children's bikes and scooters often have damaged rubber grips with exposed metal handlebar ends. This occurs through day-to-day use. Each time the child drops their bike or scooter on its side, the handlebar end contacts the ground. When it does so, the metal tube inside the rubber grip cuts into that rubber. With time, a circle is cut from the rubber end, exposing the metal pipe within.