RSA-funded researcher admits helmets could increase risk of brain injury

— Increased risk not disclosed by RSA

— RSA-funded expert not in favour of mandatory helmets

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Research funded by the Road Safety Authority shows that “in some cases” bicycle helmets increase the risk of brain injury in collisions, but this was not disclosed by the authority.

The Road Safety Authority released a press release last week highlighting where the research found some benefits of wearing bicycle helmets, but the authority made no mention of how the research also found an increased risk caused by wearing helmets in one case study — a finding which is likely to be repeated in other cases.

The RSA press release also brushed over “the elephant in the room”, starting with the line: “A UCD Professor who conducted a study of cyclists with fatal head injuries has recommended that bicycle helmets are worn to protect against head injuries in the event of a collision, particularly at speeds of less than 50km/h”, but failing at this point to state what had to be going less than that speed — motorists driving. Only after the mid-point in the long press release is a mention of drivers needing to slow down. This was reflected in media coverage last week which did not link the 50km/h speed and motorists.

Professor Michael Gilchrist, head of the School of Mechanical and Materials Engineering at UCD, confirmed the increased risk finding, but he said that more collision data collection and research was needed. On Today FM’s The Last Word with Matt Cooper last week, professor Gilchrist said “in some cases you can get increased angular accelerations wearing a helmet”.

He was responding to a statement from Shane Foran of the Galway Cycling Campaign. Foran said: “I have not had a chance to review professor Gilchrist’s paper from today, but I do know that in a previous paper he found evidence of increased angular acceleration in one paper which he presented in Germany, which was a model of a fatality involving a 27-year-old male.” We understand that the findings presented at an RSA conference last week and in the paper presented in Germany is part of the same body of work.

He continued: “Angular acceleration where somebody is wearing a helmet is basically where the rotational forces on their head are increased. That may also be associated with a risk of increased brain injury.”

Professor Michael Gilchrist, said: “Shane, you’re right in some cases you can get increased angular accelerations wearing a helmet, but in other cases you don’t.”

He said that certification of bicycle helmets only currently focuses on liner accelerations, he said that the certification standards “ignore completely the affects of rotational or angular accelerations” and that should be changed.

Gilchrist added: “Why the angular accelerations can be greater depends on a particular event and that depends on Newton’s law of motions and that’s why we need more detail accident investigation so we can do a more systematic study. Rather than make a recommendation on one isolated case.”

The paper by Gilchrist presented in Germany stated: “There are many studies linking head angular acceleration with brain injuries, especially diffuse axonal injury, as this is caused primarily by head angular acceleration”

Gilchrist also said that his research showed benefits in wearing bicycle helmets where the motorists involved in the collision is traveling at less than 50km/h, but no measurable benefits well above that speed. Campaigners say this is worrying because the RSA’s latest free-speedRSA’s latest free-speed survey shows that 83.4% of car drivers were found speeding on urban arterial roads with speed limits of 50km/h at uncontested times.

Gilchrist said: “For speeds that were relatively moderate, typically up to about 50km/h, it was pretty clear that there were benefits to had by wearing a helmet. It other words, the forces that were transmitted to the head were reduced in the presence of a helmet then if the person had not been wearing a helmet and to me that’s quite conclusive to suggest that a person should be wearing a helmet.”

He added: “What was interesting at the high speeds, at very high speeds above 50km/h, it was ambiguous. It was not very clear whether there were any there was any significant benefits to wearing a helmet.”

His research is based on computer modeling of the details of 37 cases of cycling road deaths.

He is not in favour of making helmets mandatory. On the Last Word he said: “Personally I’d be of the view that it is not in the long-term interest to make it mandatory to wear helmets… There are consequences to people’s behaviour, if it becomes mandatory then people feel that cycling is a more dangerous activity.”

Gilchrist said that policing mandatory helmets would also be an issue. This promoted presenter Matt Cooper to suggest: “But we’re able to police people going through red lights and not having lights on their bikes and they are getting their €40 fine… Why not have a similar fine if you’re riding your bike without a helmet.”

Gilchrist replied: “One could do but look at the health benefits of people cycling — if you make helmets mandatory there’s a possible consequence that fewer people will want to cycle and that can’t be a good thing.”


Asked about on-the-spot fines, Foran said: “Overall, yes, it’s a good thing that there is a more convenient way for the Gardai to apply the regulations to cyclists but we should not lose sight of the fact that we are looking at a road system which was designed often exclusively around cars and in some situations it does not make sense for cyclists to stop at every red light. I’m not talking about reckless red light running, I’m talkin about situations where in other countries cyclists would be allowed to typically turn left at a red light if they were turning onto a cycle lane.”

Overall he said it was a very welcome development, including bicycle lights not being used.


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