May 112016
 

It appears that Cricket Australia might release the findings of a safety review into the death of Phillip Hughes. This could be an interesting report to read when it comes out, in that it hints at what parts of the head are particularly vulnerable to hits from hard objects.

If you consider a cricket helmet for a moment, and contrast that to the coverage area of a bicycle helmet. Both are designed with the assumption of a collision with an object coming from in front, and so the back of the neck was not an area given much thought.

Motorcycle helmets do a lot better here in almost all cases except the “half helmets”: tick-a-box helmets if ever I saw one! More recent designs come down much lower on the head. Interestingly, professional cricket did originally start with motorcycle helmets, but found them too heavy.

Within the construction of even a motorcycle helmet however, it’s interesting to note where the foam exists: and it’s thickest around the top of the head. The sides where one’s ears would be, the foam gets thinner. Possibly a compromise for acoustic reasons, but is it significant?

Bicycle helmets however, with the exception of MTB type ones, don’t seem to cover this very well from what I’ve seen. Perhaps the back and sides needs a bit more attention. I guess I’ll have to have a gander at the report when it is released.

May 012016
 

Well, looks like this project is very much thrust into the spotlight having been covered in Hacklet 105 . Mine’s probably the least technical of the lot, it’s definitely worth having a look at what the others are doing, as there’s some really innovative ideas there. Many thanks to @Mike Szczys and @Adam Fabio for the shout-out. 🙂

One thing I haven’t done with this project yet, is to actually post the background of why I’ve started this. A big part of this was I wanted to get permission from the family of a work colleague of mine so that I could mention him by name, but at this stage, permission has not been given, so I have to keep things anonymous.

On the 12th of February, a colleague of mine was cycling to work over the Go Between Bridge here in Brisbane when he lost control on a bend as the bridge joins the Bicentennial Bikeway. This is an off-road, dedicated cycleway, so no cars, and supposedly no pedestrians, however many seem to not understand what a sign with a bicycle symbol and the letters O, N, L, Y mean. (I usually ride past and comment: “Funny bike you’re riding!”. Since this accident though, I intend to be a lot more assertive.)

(Above: the crash scene. That blood smear is still visible on the path today.)

I’m no crash investigator, but I did study physics, and I cycle as my sole means of transport myself, having no driver’s license. (And no interest in getting one either.) I’m familiar with what that bridge is like to cycle over, having done it many times shortly after it opened when I worked at West End.

Looking at the scene though, it was apparent to me that my colleague was going much faster than was sensible for that stretch of road, and something caused him to lose control just prior to the bend.

The resulting impact with the railing was devastating: in addition to a few broken bones elsewhere in the body, he suffered skull fractures, and what I understand now to be a Coup-Contrecoup injury to the brain.

I remember that morning arriving at work early (we both were early birds, and had he not crashed, he would have beaten me that morning), sitting down at my desk and preparing to do battle with U-Boot and an industrial PC, when at 6:34AM, the office phone rings. It was then I learned that my colleague was in a serious condition in hospital, and I then found myself frantically looking for contact details for his wife. (Which were nowhere to be found.)

We later learned he’d never regain consciousness, having lost all executive function in the brain. The only bits that worked, were the bits responsible for low-level muscle control. From bright mind, to persistent vegetative state. He passed away about a fortnight after his accident.

During his brief time in ICU, we were told by one of the people there that these sorts of injuries were common in bicycle and motorcycle accidents. That worried me.

That tells me that perhaps, something is wrong with these blocks of foam we insist on strapping to our heads, and that we’ve missed something. This is one of the first goals I’d like to pinpoint, but so far, has been the most difficult: trying to get hold of data that would statistically prove or disprove how “common” these injuries are.

There’s no point in protecting the skull itself if the brain is to get shaken around to the point that the person winds up with total mental incapacitation.

Research seems to suggest that helmets have had a big hand in reducing the incidents of these injuries, but the fact that it’s still “common”, seems to suggest there’s lots more work to be done.

The standards are focussed on linear acceleration, and single impacts at no more than about 20km/hr. Is that sufficient? I regularly find myself doing 40, and I’m no speed demon. (Hell, I’ve accidentally found myself doing 71km/hr once!) I think it’s time the standards were revised. The question is: how?

My colleague was a key member of our team, and one of the brighter minds I know. While he shouldn’t have taken that bend at such speed and expect to get away with it, he did not deserve to die. I can’t save him, but perhaps I can help save someone else. That’s what this project is about.

Apr 022016
 

Well, after my last couple of emails, I’ve been pointed to some rather interesting reports that peek into the area of interest.

Robin Guda at the Australian Institute of Health and Welfare was able to point me to ” Trends in serious injury due to road vehicle traffic crashes, Australia: 2001 to 2010 ” which sheds a light on serious injuries (requiring hospitalisation) from road accidents, where the patient survived. She was also able to provide a link to where I can request further information . There’s a fee involved in the latter case, but I do not mind paying a smallish amount of money for such information, alternatively, crowd-funding might be an option.

Both of these are a big help, and that article is raising some interesting questions.

One thing that stuck out was this passage (page 8):

Rates of life-threatening cases involving motorcycle riders and pedal cycle riders rose significantly over this period, with average annual increases of 5.2% and 7.5% respectively. Rates of cases involving passengers of motor vehicles and pedestrians fell, with average annual decreases of 1.2% and 1.0% respectively.

Injuries per registered motorcycle did not change much from 2001 to 2010, suggesting that the rise in population-based rates is largely due to growth in the number of motorcycles in use.

Now, due to the fact we do not have bicycle registration here in Australia, we cannot come up with a hard equivalent statistic for bicycles. Two groups I might be able to approach to get some sort of approximate figure though:

  • Peak bicycle bodies, e.g. Bicycle Queensland — who may be able to give me rough figures on the trends in membership over that period.
  • Australian Bureau of Statistics, who do the national census. One of the questions they ask is “how did you get to work that day”, so there’d be a figure there for the number of people cycling to work.

Another prospect might be to see if I can get similar stats out of China. They have a big population, many of whom ride bicycles/motorcycles, and even their bicycles are registered.

Meanwhile, Angela Watson was in touch from CARRS-Q, and was able to shed some light also. One article she posted through was ” Fatal Road Traffic Accidents, Study of Distribution, Nature and Type of Injury “.

This, in contrast to the above AIHW report, looks at accidents where the victim died within 21 days of the accident, for accidents that took place in India between December 2003 and November 2004. India have somewhat different road and safety standards to Australia, and a much bigger population. Table 6 on page 3 gives the stats for avulsion injury (that is, things getting torn off) to contre-coup injuries, cyclists and motorcyclists made up about 7% of cases there in total, with pedestrians ruling the roost.

They note there in the introduction that a big factor here is poor pedestrian infrastructure in India. If we take pedestrians out, the number rises to 7 out of 24 cases, or 29%. Probably a big portion of those were not wearing helmets, but that is pure speculation on my part.

Two other articles Angela sent through, which I’m yet to study in depth are ” Mechanisms of Head and Neck Injuries Sustainedby Helmeted Motorcyclists in Fatal Real-World Crashes:Analysis of 47 In-Depth Cases ” and ” Bicycle helmets are highly effective at preventing head injury during head impact: Head-form accelerations and injury criteria for helmeted and unhelmeted impacts “.

I will certainly have a look at these.

A very valid point was raised though regarding the availability of raw data. Much of the medical type data is heavily guarded for privacy and ethical reasons, and so getting near it may prove to be difficult. In addition, there appears to be no linkage between the stats on road accidents, and the stats on injuries.

Traffic bodies like the Queensland Department of Main Roads are mostly not concerned with details like injuries sustained, and groups like Queensland Health are mostly not concerned about whether the person was wearing a particular model helmet or whether they hit a car bonnet or a bridge railing.

A sub-area of research for me will be to get to understand the classifications for these injury types, which are covered by the ICD-10-AM standard. This is no freebie however, unlike the Australian Standards, which SAI Global sell for about $50 a piece (and I got for free when I was studying at QUT), I haven’t been able to get pricing on the ICD-10-AM standard. I guess we’ll create an account there, and ask the silly question.

The ideal situation for me would be to borrow a copy for a short period and make a note of the relevant codes. I don’t need a permanent copy. Russel suggested a couple of them in a comment a few days ago, so that’s a starting point.

In short, the road ahead is becoming a little clearer, and it’s going to be a long one. Good thing I’m not gunning for the 2016 Hackaday prize, as I’ll almost certainly not have it done by the due date.

Mar 122016
 

Well, today I received an email from the Queensland Department of Main Roads with some statistical data relating to bicycle, motorcycle and moped accidents. I thank them for their contribution.

The information is basic, but it covers the period from 2006 through to 2015, whether or not a helmet was worn, and whether the person died, was hospitalised, just received medical treatment or just had a minor injury.

Sadly, not information on whether there was TBI involved, but maybe Queensland Health could help me there. Similarly for emergency departments elsewhere in the world, I doubt the problem is just in Queensland.

I also have a fear that the information may not be tracked. I hope I’m wrong in that fear.

It’d be useful to know about upper-spinal injuries (neck vertebrae) since the weight of the helmet would be a contributor there. Basically injuries from the neck up.

I haven’t analysed the data as yet, but it’s right here if anyone wanted to look themselves.

Mar 042016
 

Well, having learned about the technical names for some of these injuries, I stumbled upon this article which describes, in lay terms, the various injury types.

Interestingly, they make reference to the cranial vault-brain dimensions that I was trying to figure out earlier:

In the subdural space is the cerebro spinal fluid. This fluid performs a number of functions, the main one being to protect the brain from impact concussion. The brain “floats” in the cerebro spinal fluid, lessening the weight on the base, and is supported at the base by the spinal cord. The brain, buoyant in the cerebro spinal fluid, can move within the cranium to a very limited degree. The space between the temporal bone and the brain is only one millimeter.

My earlier back-of-the-envelope calculation which yielded a gap of 700µm wasn’t far from the truth!

Mar 032016
 

Well, thanks to bronco71 on the BikeForums.net website , I now know what this sort of injury is called.

https://en.wikipedia.org/wiki/Coup_contrecoup_injury

There’s a lot of healthy discussion going on on the Bikeforums.net website, and a few good ideas being discussed there. Have a look .

Feb 252016
 

A work colleague, Jessie Li came up with an interesting idea this morning.

She suggested that perhaps helmets could be built to a speed rating, and give a warning to the rider when that speed is exceeded. The idea is that the helmet is matched to the likely user risk scenario.

This would be interesting to try and work in with a project like the #DIY Smart Crash Helmet project.

Feb 252016
 

One of the stated goals is to try and determine how statistically significant TBI is in motorcycle and bicycle accidents.

Null hypothesis here will be that motorcycle accidents will have a much higher prevalence of TBI than in bicycle accidents, down to the typical routes and speeds alone.

Nick Rushworth, executive officer of Brain Injury Australia has been most helpful in pointing me to some statistics on New South Wales road crashes as well as some more general statistics from 2004-05 on TBI cases in general . His assistance in this has been a big help.

The Queensland Department of Main Roads also produces a number of reports, as well as a request form. Transport for NSW also provide statistics. I think the data is there, we’ve just got to figure out a means to drill into it.