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

In other news...

[K. S. Kyosuke]

Green military uniforms have also been observed to be a cause of brain damage, proportional to the number of stars on the uniform.

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:In other news...

[Gilmoure]

I was underweight for my height (5'10" / 115 lbs). After spending 6 months trying to gain weight, was able to get a waver and go in to basic. 4 years later, had managed to gain 12 lbs. Out on the flight line, they called me Stickman. I was able to get in through small access holes (KC-135's) and fix stuff that would have taken an extra hour of work to remove larger pieces of skin. Got a decent amount of free booze for helping speed up repairs.

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...

[gnick]

Maybe our helmets need a warning label: War may be hazardous to your health and has been known to cause such side effects as brain damage, PTSD, maiming, and death in many people during and after exposure.

War may be dangerous

[Anonymous Coward]

You have been warned.

Great Headline.

[Caue]

Maybe it should have been "explosions cause brain damage and the helmet is not very efficient against those" or "don't wear a military helmet and use TNT"

I tought helmets were designed to protect from debri and flying objects caused by explosions, not the shockwave from 2 pounds of C-4 lying around.

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

[Firethorn]

Actually, there's some very good reasons for calling them IEDs. IED stands for Improvised Explosive Device, of course. What this means is that the explosive device in question is not standard. This matters when it comes to disarming/making them safe.

If a EOD guy comes across an unexploded MK82, he knows precisely how to disarm it - it's standardized. Same deal with most land mines*, claymore devices, unmodified artillery shells**, and the rest of the world's standard military munitions. We even have books on foreign country's stuff, including Russian and old USSR weapons.

Each IED, even if from the same maker, is far more unique, presenting unique challanges when it comes to disarming them.

Oh, and being designated as a land mine doesn't mean a 'large enough' payload, it means it's buried in the ground with an appropriate sensor/detonator to explode when something's over it. Most are pressure sensitive, some anti-vehicle types have magnetic detonators.

Bombs are generally assumed to be dropped out of planes, but then I'm Air Force.

*Though booby-trapping can be an issue with these.
**Many are converted into IEDs via non-conventional detonation systems in Iraq/Afghanistan.

Gloves make boxing *MUCH* more dangerous

[Joce640k]

They also make it possible to hit the head. Without gloves you'd break your hands if you stood there punching at somebody's head. In the old days of bare-knuckle boxing most of the blows were to the body. There were a lot of bruised ribs but hardly anybody died.

Opinion of a Soldier

[slpalmer]

I think a lot of this stems from the way the current helmet is fitted to the soldiers head. (Yes, I am a soldier, 18th Airborne Corp, Ft Bragg, NC)

  1 - The older Kevlar helmet was fitted to your head with a "sweat band" strapped to the inside of the helmet, which could be adjusted to fit your head exactly.

  2 - The newer ACH (Advanced Combat Helmet) is fitted with velcro backed pads which attach inside the helmet.

Let me say now that it is *very* common for CIF (where you get issued your equipment) to be out of your size and give you the next size up. With the older Kevlar (case 1 above) you could still fit the sweat band to fit your head, securing the helmet. With the ACH (case 2 above) if the helmet is too big, the pads will be loose on your head, and the helmet will rattle around on your head when concussions occur nearby.