There are newer helmet technologies that are supposed to absorb more of the impact, and in particular allow some slippage of the shell to reduce rotation, which can be one of the most harmful types of movement:
https://www.popularmechanics.com/adventure/sports/news/a2797...
Whether these will be effective at preventing CTE, or only preventing concussions, is hard to say without a lot more data.
The brain suffers damage from slamming against the inside of the skull due to inertia changes during collisions that are inherent to the sport.
There is literally no way to protect the brain as the sport is played today.
Yes, that's the inertia change I referenced.
A crumple zone is unlikely to mitigate the problem in any meaningful way. The problem is that in a hard collision, the head still stops in an instant, but the brain continues to travel at the same rate of speed until it slams into the skull. Effectively slowing the distance over which the head comes to a stop by a few millimeters or so won't meaningfully offset that impact. The brain is still traveling too fast.
The kind of design you're referencing works in vehicles because its purpose is to dissipate the energy of the collision around the zones instead of through the vehicle. But, the goal here is to avoid damaging the vehicle so extensively that the damage intrudes upon the cabin (and its occupant).
However, the vehicle's deceleration itself is not altered in any meaningful way by crumple zones. So, this system really only works if the driver is restrained (e.g. by a seat-belt). Otherwise, the driver would still bear the force of the sudden deceleration when she collided with whatever was on the other side of the empty space in front of her.
Similarly, if the brain could be restrained in its skull, then helmets might have at least some value in protecting it.
The NFL has a long history of pointing to new technology that promises to make the game safer, but I have yet to see that manifest in reduced concussions. I'm also skeptical that increased cushioning wouldn't just let players hit each other at higher speeds.
But CTE is about repeated impact, so most CTE cases now are from previous poor helmet designs, not from modern helmets.
Also because of the repeated nature, single impact helmets aren't the important ones. Linemen have the biggest problems and they aren't the ones getting laid out from thunderous impacts like a receiver.
To protect against those, modern helmets have stronger face masks and wider field of vision so a ball carrier can see it coming better. It is those blind hits that hurt.
I hope to see modern CTE rates come down from improved helmets but it will take a decade plus to see the results in the pros.
http://www.foxnews.com/tech/2017/08/08/revolutionary-new-zer...
The helmets would need frequent changing, or else they might look like demolition derby cars by halftime.
The very existence of hard plastic helmets is what has caused the issue in the first place. It creates enough protection that people are able to hit much, much harder than normal, which causes concussion/CTE. You can fix the game by getting rid of the pads.
Think of the crash like a train... if the locomotive can't get traction to go fast, the passenger cars can't fly thru the air at 100 MPH in a derailment, can they? So eliminate shoe cleats. Maybe eliminate shoes and play barefoot on grass. If your feet literally can't accelerate you to 15 mph in one meters length, then you can't hit someone's head at 15 mph when you eventually get there.
There are other interesting rule peculiarities that have nothing to do with equipment. There seems no reason other than sheer display of aerobic conditioning to require wide receivers to line up on one side of a line an dash 50 yards downfield to get smashed into and killed by another guy dashing 50 yards as fast as he can trying to stop him. So change the rules so they don't run as fast as they can? Just let pass receivers stand around downfield, or let defensive backs line up there if they want. If you have to run 25 yards in three seconds to hit a guy catching a ball, someone is going to get killed. If you're lined up a foot away from the catcher, you don't need to kill him to get there in time. Sometimes the best improvement to equipment is to make it not used, in this manner.
Another strange rule change is you have to try to kill the wide receiver because running yards made after a catch count, although trying to kill the receiver before the pass is pass interference with a free down, so an interesting compromise is no running yards after a pass along with any tackling of a receiver an automatic pass interference 1st down or half the distance to the goal. Where the receiver's feet are located when the pass is complete is where the play ends, not where the receiver was tackled after an attempt at a run. This would tend to make the game immensely more exciting because there will be even more aerobic running downfield and more exciting interceptions, vs a tendency to tempt the defensive line into an illegal tackle via short passes.
Another strange rule is offensive and defensive lines symbolically fighting and pushing each other is acceptable, leading to a lot of physical damage. A rule as simple as you touch an opposing player you're both out of the play would be interesting to see. You don't have to hit a guy hard enough to kill him to get him out of the play, just merely touch him. Its easy to kill someone by trying to charge into them so hard you literally flip them over, but hard to kill someone by high-five-ing them as you pass by. I imagine you'd see some amazing dodgeball like madness as players try to remain untouched as late as possible in the play.
Since we just made the whole game about passing without contact, 4 downs seems a bit too generous. Change possession whenever the offense fails to advance for whatever reason.
And 22 players on the field at once is just a bit much. So many variables. So cut that down to 7 players on each team.
And maybe to promote skillful passing, ditch that weird oblong ball and replace it with a flat plastic disk.
This is probably the origins of the grand bascinet, where a knight's outer helmet were strapped to his chest: so the force could be dissipated. But they severely restricted movement and athleticism: you wouldn't be able to turn your head in a different direction than you are running to look for the ball, for example.
I think it may be better to actually provide less protection and/or reduce designs that mitigate or otherwise disguise the immediate physical consequences of doing things like spearing another player head first.