Military Helmet Design Contributes To Brain Damage

BuzzSkyline writes "Improvements in helmets have helped modern soldiers survive bullets and blasts that would have killed them in past wars. But increasing numbers of soldiers are suffering long lasting brain damage from explosions, partly as a result of what appears to be a flaw in helmet designs. Although the blast itself may not accelerate the brain inside a soldier's head enough to cause injury, shockwaves that make it through the space between a helmet and a soldier's head can cause the skull to flex, leading to ripples in the skull that can create damaging pressures in the brain. Simulations that relied on 'code originally designed to simulate how a detonated weapon rattles a building or tank' could lead to new helmets that reduce the traumatic brain injuries that many soldiers suffer as a result of improvised explosive devices and other moderate-sized blasts. The research is due to be published in Physical Review Letters, but a pre-print of the entire article is currently available on the Physics ArXiv."

Comments

That's a bit harsh...

[clone53421]

Helmets which "have helped modern soldiers survive bullets and blasts that would have killed them in past wars" are being accused of causing brain damage.

I guess boxing gloves cause brain damage, too? Or maybe it's boxing that causes brain damage, and the gloves reduce the risk...

Now, if they can make better helmets that reduce the risk of brain damage even further, props to them. That doesn't mean the current generation of helmets are "causing" brain damage.

Re:That's a bit harsh...

[szo]

It's 'causing' the brain damage in a way that it prevents the solder from dying and thus hiding the symptoms of the brain damage :)

Re:That's a bit harsh...

[PyroMosh]

Unlikely. I have no idea if it's a real disease or not, or a popular misdiagnosis for a lot of other unrelated things. However, a great number of Gulf War Syndrome cases are with personnel who were not exposed to combat. Airmen on airbases, logistics folks, troops who never saw any real resistance in action, etc., etc.

In other words, not a lot of soldiers were exposed to explosions at close range, and a great many more folks than that tiny cross section reported GWS.

If it's real, it would have to be caused by something either pathogenic (unlikely, given that it seems the disease was not brought back home and spread to others) or environmental.

Environmental causes seem more likely because of the sheer number of possible candidates.

1. Burning oil wells, and the chemical muck that produced
2. The first wide scale use of depleted uranium munitions
3. Exposure to chemical weapons. Although chemical erapons were not deployed by Iraq during the war, some troops were exposed incidentally when storage facilities were destroyed.
4. Chemical agents and vaccines used to protect against chemical and biological weapons

All of these are suspect. There are studies saying yes, and no to most, if not all of these possible sources. Compound that with the real probability, that even if it's real, a great number of cases are probably folks who are scared and have some other disorder, who have convinced themselves otherwise, on top of the unscrupulous folks who are trying to turn this into a personal payday... we may never know if it's real, let alone what causes it if it is.

Re:Scary

[ArbitraryDescriptor]

Certainly it's possible, they just need better shock absorption. The current design transmits too much of the shock to the skull.

This problem is actually caused by the helmet's method of not transmitting shock to the skull. FTA:

To protect soldiers from bullets and shrapnel, modern helmet design maintains a 1.3-cm gap between helmet and head; in the simulation, the blast wave washed into the helmet through this gap. "The helmet acts as a windscoop, so the pressure between the skull and helmet is larger than the blast wave by itself," King said. While the ACH's pads mostly prevented this underwash, they also passed on forces to the skull.

So the trick is keeping the overpressure out of the helmet, while keeping it separated from the skull. Perhaps a dual helmet design; Rigid outer shell to absorb and deflect impact, and a second separate inner covering to resist overpressure. Either that, or in place of ACH pads, some type of system relying on fluid dynamics to redirects force forward, out the face of the helmet, rather than inward toward the skull.

Re:Stop calling it IED

[Tx]

Actually, while there is plenty of military doublespeak that could be dispensed with, "IED" I am perfectly happy with. "Improvised" is a worthwhile adjective to use in this context, because the improvised devices do typically have different characteristics from the closest equivalent professionally made devices, so you want to use that or some other adjective (you could use "home made" if you like, but that sounds like you're talking about pie, not weaponry). And since the term covers a range of blast, shrapnel, and incendiary devices, "explosive device" pretty much covers it. For once, it's actually a concise and descriptive acronym.

Re:In other news...

[evanbd]

You know, observational studies are still scientific. There are plenty of hypotheses that can be tested without randomized controlled trials.

You're not going to claim that if astronomers really wanted to be scientific, they would start their research by gathering up a bunch of hydrogen and piling it together in empty space and then watching what happens, are you?

It's also entirely possible your test methodology would fail. The helmet could well be preventing acute injury resulting in death (shrapnel through the skull), but increasing the diffuse brain damage to other parts of the brain. However, the death due to acute injury would make the diffuse injury rate difficult to determine. Preventing death but causing brain damage is clearly an improvement, but it doesn't mean the helmet merely "failed to completely prevent" the brain damage, if the brain damage wouldn't have occurred without it.

Sometimes science is hard. It's still science, though, even if your "ideal" test methodology is impractical.

Re:Stop calling it IED

[russotto]

So what is it when it's made from artillery shells?

I'll bet there's an army manual somewhere which says so. Probably if the artillery shells are used as artillery shells, they're not considered IEDs, but if they're rigged as a claymore, they are. Sort of like if you somehow hooked a billiard ball to your mouse to make a trackball, you'd have an IPD -- improvised pointing device.

That is "dead" on

[CFD339]

My read was exactly the same. The helmets are now so much better at protecting heads than anything ever has been in the past, that we're having to model air pressure caused skull flex in order to find something to make better. That's fantastic! Not too long ago the trauma was more likely to be a piece of a bomb going through the brain that caused the damage.

And yeah -- anything they can do to make them better is a good thing, but lets applaud how far they've come.

The only thing I'd add, is that if we could find a way to have less soldiers in the way of bombs and bullets, we could be less aggressive on helmet designs too. Ah well.