Souped-up mopeds
Research reveals that motorcycles are the deadliest means of motorised two-wheel transport. Another striking fact: riders of motorised bikes suffer from serious head injuries far more often.
Bart Braun
Thursday 6 December 2012

BY Bart Braun If you didn't know what a motor bike was, you would invent one after just one look at a traffic jam. It's not surprising that the number of motor cyclists in the Netherlands has risen steeply in the last fifteen years, and that more people are riding mopeds and motorised bicycles too. However, what you gain in versatility, you lose in safety: motorised bicycles do not have cage constructions, air bags or seat belts. Despite that, the number of traffic deaths in the Netherlands has been falling for years: in the year of the most fatalities, 1972, the number was five times as high as the figure for 2011, while the number of fatal accidents involving two-wheelers is declining too.

That's good news, but isn't much help if you are actually involved in a traffic accident. A group of researchers, most of whom are from Leiden, examined the figures for motor bikes, mopeds and motorised bicycles with light engines in Nederlands Tijdschrift voor Geneeskunde [The Dutch Journal of Medicine]. Between 1993 and 2008, about 37,779 motor-bike accidents, 115,054 moped accidents and 20,429 accidents with motorised bicycles were registered in the Netherlands. 28 per cent of the motor cyclists needed hospital treatment, against approximately one sixth of the other categories, and motor bike accidents resulted in the most deaths: 1,342.

Men are strongly overrepresented in the figures – men account for more than eighty per cent of the victims. The chances of physical injury or death are relatively higher among younger road users, perhaps because they are less experienced and more reckless, and among people over fifty-five. "The elderly have less capacity for recovery from blood loss, for example, and are more likely to have additional disorders such as diabetes," remarks Inger Schipper, a trauma surgeon at Leiden University Medical Centre and the main author of the NTvG article. "This is a really Dutch study. Much of what you read about traffic accidents comes from America, and the traffic situation there is very different, with fewer mopeds and cyclists and so on."

Her job at A&E gives the stark figures a human face, and jargon like "serious morbidity" becomes a real victim with terrible injuries. "You can recognise the motor bike accidents quite easily. The article explains that motor cyclists often have injuries to the extremities, and that is absolutely true. Motor cyclists often break everything: upper arms, lower arms and wrists."

There is another striking fact: riders of motorised bikes suffer from serious head injuries far more often, and they have the greatest chance of dying in hospital. Nowadays, electric bikes are not stuffy Spartamets for people who have trouble walking any more: young people ride them too. Schipper adds: "They tend to soup up their engines. By law, they are not allowed to go faster than 25 kilometres per hour, but I've been overtaken by motorised bikes when I've been driving faster than that in my car." More than half of the motorised-bike riders who end up in hospital after an accident are under twenty-five. Why would a self-respecting sixteen-year old buy a motorised bike if he can buy a moped instead? Well, because he doesn't need to wear a helmet, that's why, which brings us to the topic of head injury.

The faster you go, the harder the smack when you come to a sudden halt. "If you were going faster than twenty kilometres per hours, we call it high-energy trauma. The injuries are more extensive, and often include things like a ruptured spleen or fractured pelvis." A motorised bike may go faster than that, even if you do not allow for the speed of oncoming traffic. And that is why the authors of the NTvG article are calling for helmet laws for motorised bikes, or, as Schipper says: "You could recommend wearing a helmet, given the morbidity and mortality."

The research did not include non-motorised bikes, but Schipper and Co. intend to incorporate them in a follow-up study. The SWOV Institute for Road Safety Research states on its website that the number of fatal bike accidents might be dropping but the number of cyclists who are hospitalised is rising slightly. Almost half of them have head injuries or brain damage. A helmet reduces the risks of that type of injury by half, but in countries where helmets are mandatory for cyclists, the popularity of bikes has dropped.

In addition, psychologists have indications that drivers tend to overtake cyclists less carefully if they notice that the cyclists are wearing helmets. At least, experiments seem to point to that. If that happened on a larger scale, you would expect the number of accidents involving both cars and bikes would increase a little in countries that have just introduced helmet laws, but that doesn't seem to be the case.

Even if you were to support helmet laws, it would not be feasible to introduce them to the Netherlands for time being, which is why the SWOV has suggested that air bags on car windscreens might protect cyclists in crashes. Schipper is not very enthusiastic: "You would be protecting the dangerous outside world against crashes instead of teaching people to protect themselves."