|  | 
| Riddell's Air Bladder Design | 
While I’m sure there’s been an understood relationship between football and head injuries for as long as the game has existed, it’s important to recognize that football’s “concussion crisis” is a relatively new phenomenon. Concussions were rarely talked about 10 years ago, let alone 45 years ago when the development of the air bladder system formulated the technology that is still used in helmets today. And therein lies the problem with contemporary helmets: they’re designed to prevent catastrophic head injuries (ie skull fractures), but don’t actually do much to prevent concussions. Because concussions are internal injuries, where a blow to the head causes the brain, suspended in cerebrospinal fluid, to slosh around and receive axonal damage by bumping into the interior walls of the skull, a hard protective layer around the head doesn’t do a lot to prevent these injuries. Think about an egg. Let’s say you created some sort of hard layer to put an egg in that would protect the shell. If you dropped the egg on the floor, you might prevent the shell from cracking, but you’re not going to be able to prevent the yolk inside of the egg from moving around.
Medical professionals and helmet manufacturers alike recognize this problem. Many months ago, I wrote a post on how every football helmet has a warning sticker on the back of it. Different manufacturers use slightly different language in their warnings, but they all concede that no helmet can prevent brain injuries. This problem is especially true in the case of hits to the head that cause rotational forces, because again, it’s the internal movement of the brain that causes concussions, not necessarily the amount of blunt force applied to an area. Dr. Frank Conidi, a professor of neurology at the Florida State University College of Medicine and director of the Florida Center for Headache and Sports Neurology, stated in 2014 that “biomechanics researchers have long understood that rotational forces, not linear forces, are responsible for serious brain damage including concussion, brain injury complications and brain bleeds.”
Therefore, for all the advancements made in helmet technology in the past few decades, there are really only a couple that I can think of that actually help disperse rotational forces, and they’re both arguably not that significant. The first is that modern helmets are actually rounder than they were in the 1970s and 1980s. As you can see in the picture of Mike Ditka below, helmets used to be more in the shape of an oval, similar to how the human head is shaped.
However, the more spherical two objects are, the less surface area will come in contact between them should they collide. So theoretically, rounder football helmets are safer because direct the surface area of helmet-to-helmet can be diminished a bit, especially if hits are coming at odd angles. The second thing is something I don’t know if I’d call an “innovation,” because it’s been around for decades, and it’s difficult to argue not only whether it’s deliberate or not, but also if it’s even true, especially because I’ve never seen a study confirm or even attempt to confirm this belief. But regardless, some people also believe that the glossy finishes on football helmets reduces friction between helmets that collide, and thus disperses rotational forces more than matte finished helmets would. Whether there’s any veracity in that claim, I’m not sure. But I can see the logic.
 But anyway, the question for the future of football helmet technology is what can done to absorb rotational forces. Like I said earlier, theoretically with the air bladder system, the fit of the helmet is so snug that the entire head of a player would move if his facemask would move. And clearly, that might not be the best system for reducing rotational forces. There are currently a couple helmet companies that already have produced helmet models constructed with rotational forced in mind. One is the company Xenith. Their helmets don't use air bladders, and instead fit the helmet with a web system that tightens or expands using the chinstrap, which is connected to the interior structure of the helmet. One of the their models, the Xenith X2, is pictured on the right. The shell of the helmet can rotate independently of the white web that surrounds the player's head, theoretically helping to disperse the rotational forces that impact the head. Xenith helmets certainly aren't the most popular in the NFL, but you'll definitely see them occasionally and their popularity has definitely grown in the past few years. Another company, VICIS, a startup based in Seattle, is also developing a helmet with the idea of dispersing rotational forces. Their helmet design, called ZERO1, also doesn't use an air bladder. The outer layer of their helmet consist of many columns which can both compress and also move laterally, therefore absorbing forces from any angle. More uniquely, the shell of the helmet isn't perfectly rigid like that of other helmets, and instead gives a big to further absorb impact and disperse force. Check out the video below to learn more about the ZERO1. These helmets are still being tested and developed, but it'd be pretty cool to see them at the NFL, NCAA, and high school levels in coming years. Overall, hopefully the new NOCSAE tests will incentivize even more helmet companies to develop technology aimed at absorbing and dispersing rotational forces.
But anyway, the question for the future of football helmet technology is what can done to absorb rotational forces. Like I said earlier, theoretically with the air bladder system, the fit of the helmet is so snug that the entire head of a player would move if his facemask would move. And clearly, that might not be the best system for reducing rotational forces. There are currently a couple helmet companies that already have produced helmet models constructed with rotational forced in mind. One is the company Xenith. Their helmets don't use air bladders, and instead fit the helmet with a web system that tightens or expands using the chinstrap, which is connected to the interior structure of the helmet. One of the their models, the Xenith X2, is pictured on the right. The shell of the helmet can rotate independently of the white web that surrounds the player's head, theoretically helping to disperse the rotational forces that impact the head. Xenith helmets certainly aren't the most popular in the NFL, but you'll definitely see them occasionally and their popularity has definitely grown in the past few years. Another company, VICIS, a startup based in Seattle, is also developing a helmet with the idea of dispersing rotational forces. Their helmet design, called ZERO1, also doesn't use an air bladder. The outer layer of their helmet consist of many columns which can both compress and also move laterally, therefore absorbing forces from any angle. More uniquely, the shell of the helmet isn't perfectly rigid like that of other helmets, and instead gives a big to further absorb impact and disperse force. Check out the video below to learn more about the ZERO1. These helmets are still being tested and developed, but it'd be pretty cool to see them at the NFL, NCAA, and high school levels in coming years. Overall, hopefully the new NOCSAE tests will incentivize even more helmet companies to develop technology aimed at absorbing and dispersing rotational forces.
 

