New Forest cyclist unscathed after crashing into tractor bucket on descent

AndyRed3d]</p>

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[quote=AndyRed3d

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So as I said, smacking you head on the ground at 12.3mph, with a helmet your head will experience a peak of around 150g (which makes a sort of 'douf' noise and is clearly very unpleasant), whilst without a helmet it will experience a peak of around 1200g (which makes nasty sharp bang noise and is pretty deadly).

How much is "pretty deadly", how many people die per head strike that reaches or exceeds this number.

Given the number of actual admittances to hospitals of people with head injuries from far more than trips (which as we know an adult head will exceed 12.3mph in that simple trip from walking speed)  so it would seem that your figure is either incorrect or that 'pretty deadly' should really just be sometimes deadly, in fact 200g can sometimes be deadly also.

You infer that the 1200g peak figure is where death occurs often, I'd like to see some numbers on that please.

BehindTheBikesheds wrote:

AndyRed3d wrote:

So as I said, smacking you head on the ground at 12.3mph, with a helmet your head will experience a peak of around 150g (which makes a sort of 'douf' noise and is clearly very unpleasant), whilst without a helmet it will experience a peak of around 1200g (which makes nasty sharp bang noise and is pretty deadly).

How much is "pretty deadly", how many people die per head strike that reaches or exceeds this number.

Given the number of actual admittances to hospitals of people with head injuries from far more than trips (which as we know an adult head will exceed 12.3mph in that simple trip from walking speed)  so it would seem that your figure is either incorrect or that 'pretty deadly' should really just be sometimes deadly, in fact 200g can sometimes be deadly also.

You infer that the 1200g peak figure is where death occurs often, I'd like to see some numbers on that please.

OK, 'g' is already quite confusing for people, so I was trying not to overload this with any more detail... just to be clear I wasn't talking about 'types of accident', i.e. how the head could get there -  I was just talking about the measurable result when a head hits something hard at a specific speed. This is nothing to do with hospital admission statistics, 'survivability of g forces' has been determined in a completely different way.

< 250g is widely accepted as a 'survivability level'. I am not actually sure where this came from. through there are rumours that it originated from work carried out by the Nazi's (mind boggles) but I've never been able to find evidence of that. That level seems to have been tested over time and continues to be accepted as a reasonable basis.

Of course we also all fuly understand that this is complicated by many factors: not least by the brain, fluid, skull structure being a complex shape and system; in terms of the person themselves - age, hydration levels, genetics, previous exposure to impacts and damage; and then the nature of the impact - the input speed, direction and location of impact, rotation (dangerous due to damage all the way round the outside of the brain on the nobbly bones inside your head), multiple impacts or skull damage...

So 250g is a somewhat averaged out 'dumb' guideline.

If you are genuinely interested, then here's study where they included computer finite element analysis of a 3D skull/brain model, and the accelerations / strains on the brain material, which they then compared with previous impact studies on human cadaver heads, to validate correlations between the speed of impact and injury level:
https://www.internationalbrain.org/examination-of-bi-thresholds-in-terms...

Also if you want to learn more about the causes and process of tramatic head injury, there's an in-depth general decriptive paper here:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4694720/

Enjoy the read!

AndyRed3d wrote:

BehindTheBikesheds wrote:

AndyRed3d wrote:

So as I said, smacking you head on the ground at 12.3mph, with a helmet your head will experience a peak of around 150g (which makes a sort of 'douf' noise and is clearly very unpleasant), whilst without a helmet it will experience a peak of around 1200g (which makes nasty sharp bang noise and is pretty deadly).

How much is "pretty deadly", how many people die per head strike that reaches or exceeds this number.

Given the number of actual admittances to hospitals of people with head injuries from far more than trips (which as we know an adult head will exceed 12.3mph in that simple trip from walking speed)  so it would seem that your figure is either incorrect or that 'pretty deadly' should really just be sometimes deadly, in fact 200g can sometimes be deadly also.

You infer that the 1200g peak figure is where death occurs often, I'd like to see some numbers on that please.

OK, 'g' is already quite confusing for people, so I was trying not to overload this with any more detail... just to be clear I wasn't talking about 'types of accident', i.e. how the head could get there -  I was just talking about the measurable result when a head hits something hard at a specific speed. This is nothing to do with hospital admission statistics, 'survivability of g forces' has been determined in a completely different way.

< 250g is widely accepted as a 'survivability level'. I am not actually sure where this came from. through there are rumours that it originated from work carried out by the Nazi's (mind boggles) but I've never been able to find evidence of that. That level seems to have been tested over time and continues to be accepted as a reasonable basis.

Of course we also all fuly understand that this is complicated by many factors: not least by the brain, fluid, skull structure being a complex shape and system; in terms of the person themselves - age, hydration levels, genetics, previous exposure to impacts and damage; and then the nature of the impact - the input speed, direction and location of impact, rotation (dangerous due to damage all the way round the outside of the brain on the nobbly bones inside your head), multiple impacts or skull damage...

So 250g is a somewhat averaged out 'dumb' guideline.

If you are genuinely interested, then here's study where they included computer finite element analysis of a 3D skull/brain model, and the accelerations / strains on the brain material, which they then compared with previous impact studies on human cadaver heads, to validate correlations between the speed of impact and injury level:
https://www.internationalbrain.org/examination-of-bi-thresholds-in-terms...

Also if you want to learn more about the causes and process of tramatic head injury, there's an in-depth general decriptive paper here:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4694720/

Enjoy the read!

I read plenty of studies/data from the US in the 70s that were from real life scenarios no 3d printed models, those datasets including babies falling from height. It's fairly interestuing that the the forces in NFL is around 150 near the top end and 100g is common place, yet the concussive forces even with helmets has not prevented the massive CTE problems experienced by players.

The approach now is to reduce the actions of those presenting the harm as a method to reduce long term brain (not head as I first stated) injuries, this is the most effective since the helmets clearly don't work to prevent brain injuries in any meaningful way. Notice the huge difference between rugby (league and union) were helmets are not used and whilst players do suffer concussions and they can be quite bad, the actions of the players has a far greater influence on the outcome, when gridiron added helmets to their players they simply signed a death warrant to many players and many hundreds of thousands of brain injured players that suffered the rest of their lives.

Even the head gear in boxing had the negative effect with respect to concussions and hence why the ABA decided to remove them for amateur boxing after they looked at the stats which showed a riduclously large increase, not surprising to myself nor my brother who was a decent amateur in the 80s when they weren't worn.

You can take any sport you like, baseball, Ice hockey, cricket, not a single sport has had any improvement in head injuries since they mandated helmets, in fact for cricket at least they have got worse, in exactly the same situation as for NFL, for cycling and elsewhere, greater risk taking which then produces more incidents and produce more exceeding of any protective ability of the safety aid worn.

It's pretty logical as to why helmets fail to protect at population and individual level basis.

maldin wrote:

The only “lucky” thing about it was that I took responsibility for my own safety to the extent that I could and protected the most fragile part of my body to what small degree I could. Each to his own, I just happen to prefer my life with a slightly lower risk of brain damage.

Makes me wonder where you think your brain is if you are protecting it by protecting the most fragile part of your body