Unique Helmet Design Could Reduce Concussions

May 18, 2009

7 Min Read
Unique Helmet Design Could Reduce Concussions

Anew helmet designed by Massachusetts-based Xenith™ LLC is targeting safety through innovation and education, and may, the company says, decrease the number of concussions sustained by even the hardest-hit football players.

Vin Ferrara, MD, MBA, founder, president and CEO of Xenith™ LLC, says players experiencing injuries commonly described as “bell-ringers” or “dings” are players who have actually suffered concussions. Therefore, the number of these injuries is much higher than previously believed.

A major cause of concern is that players who have experienced concussions do not always report them. Coaches, parents, officials and medical staff may be unaware of the injury. Repeated injuries can occur more easily and with worsened long-term consequences.

A concussion is a type of traumatic brain injury resulting from the sudden violent movement of the head during impact. Sudden movement of the head causes the brain to move inside the skull, which may result in disrupted brain function, leading to the signs and symptoms of concussion.

A New Approach to Helmet Function

Football has come a long way since the first so-called football game was played between Rutgers and Princeton in 1869. The format has evolved, as well, as that game was played under Rugby-style rules. The Harvard-McGill game in 1874 and the Tufts-Harvard game of 1875 marked an evolutionary point between a rugby-soccer format and the game we know as American football today. As the game evolved, so did helmet design.

Xenith™'s stated mission is to advance safety and activity through innovation and education. To do this, it started by creating its own unique approach to helmet design.

Helmets widely in use today employ foam or other padding as a means of dissipating impact energy. These helmets and other head protection systems are tested by impacting a crash test dummy head, which measures the sudden movement in units of G or SI — a severity index, Ferrara says. The dummy head registers an acceleration curve, representing the force the head experiences. The lower the peak, the lower the G or SI. A lower, flatter curve indicates a more gradual movement and less likelihood of an injury. However, performance on standards does not necessarily correlate with the risk of concussion.

The challenge with helmets is trying to minimize the peak G and SI during any impact, which is usually unpredictable with regard to magnitude and direction. According to Xenith™, a helmet's effectiveness is dependent upon the energy management system it uses and how well the system relates to the impact. If the system is too soft, it collapses too quickly and could result in a skull fracture or brain injury. If the system is too hard, it won't collapse enough, resulting in a sudden, jolting impact that can cause a concussion.

Thinking inside the helmet, the Xenith™ team applied principles employed in automotive shock absorbers to a new head protection system called Xenith™ Adaptive Head Protection™, which is the basis for the company's new X1 Football Helmet. Shock absorbers work by adapting to the impact to minimize the force to the car resulting from the variable bumps in the road, and Xenith™ applied this principle to what the company calls the Aware-Flow™ Shock Absorber.

The Aware-Flow™ Shock Absorber replaces traditional foam or padding in the helmet. Multiple shock absorbers are embedded in a flexible bonnet with a series of holes where the anti-bacterial thermoplastic polyurethane disc-shaped shock absorbers are placed (see Figure 1, page M14). The absorbers' energy attenuation air chambers are fitted with a small hole allowing air to escape when impact occurs.

The engineering principle involved is somewhat like that of a bicycle tire pump. Pushing the handle slowly allows air to enter the tire relatively easily, but when the handle is pushed rapidly, resistance is encountered. This is because of air turbulence. Similarly, in a low-impact situation, air flows out smoothly from helmet shock absorbers, which behave like something soft. In a high-impact situation, the air becomes turbulent and the shock absorbers behave like something stiff.

This principle allows the shock absorber to adapt to impact energy, and the bonnet suspension allows the system to adapt to impact direction. The system deflects in relation to the magnitude and direction of impact, dissipating impact energy and reducing the sudden movement of the head, thus reducing the likelihood of brain injury. The absorbers refill instantly after impact by simply springing back to shape and inhaling the air around them, ready for the next hit (see Figures 2, 3 and 4, left).

The improvement in performance is shown by a wider, flatter acceleration curve. Further, the shock absorbers show essentially no decline in function over repeated impact.

A New Approach to Helmet Fit and Comfort

Football helmets may look sharp on team members' heads and may reduce impact energy, but they also need to be comfortable and well-fitting. Xenith™ addressed the comfort and fit factor through its Fit Seeker™ design, utilizing the flexible bonnet and a cable system that integrates with the chinstrap and chincup.

The cable travels from the back of the helmet through the bonnet and down toward the chincup, which acts as a redirection pulley. When the player pulls the chinstraps, the chincup is pulled up toward the chin and the bonnet is pulled snugly down around the head. The straps are then snapped onto the helmet shell. The result is a custom fit, which makes helmets less susceptible to being knocked off during impact. Ferrara also points out that other helmet fit systems require pumps to inflate bladders, which is often a bane to coaches and equipment managers. Fit Seeker™ eliminates the need for pumps (see Figures 5.1, 5.2 and 5.3, below left).

Furthering the comfort factor, air is permitted to circulate freely through the helmet, including moving upward from the player's neck, and is vented from slots on each side.

Education and Prevention — the Best Solution

Although its new design goes a long way to reducing the risk and severity of concussion, Xenith™ makes no claim its helmet will eliminate the concussion epidemic. Players, parents, coaches, officials and anyone else involved in the sport must be aware of the signs and symptoms of concussion, the company cautions. Signs such as loss of consciousness or balance, obvious confusion or vomiting are observable by others. Symptoms, which are far more common than signs, are experienced only by the player. They include nausea, blurry vision, unusual sweating, headaches and disorientation, indicating a possible concussion.

Unfortunately, in many instances players ignore symptoms to stay in the game. Ignoring the symptoms can have long-term consequences with effects lasting for days, months or becoming permanent. The dangers are increased with repeated impacts.

Xenith™ says the new helmets are sparking interest among the hundreds of teams that wore them during the past football season, including nearly 100 colleges and more than 400 high schools. “Players are saying a lot of great things, including a reduction of headaches and stating that they feel the impacts less,” Ferrara says. He also cautions that the real key to reducing the burden of traumatic brain injury is an improvement in technique and rule enforcement.

“While rules are in place to discourage head-to-head contact, which is the main cause of concussions and neck injuries, they are rarely enforced,” he says. To emphasize this point, Ferrara found a picture of himself as a high school player, leading with his head while being tackled by another player doing the same. Ferrara included this image in the Xenith™ product catalog and other promotional materials, as a way of showing what not to do.

“There is an official in the picture looking right at us and not making a spearing call,” he says. “We need officials and coaches to take a role in eliminating this injury, and I've found that many people are ready to do this. If we can actually make the game safer, it will increase participation and the quality of play. Then the benefits of an innovation and education approach can be applied to other sports, as well.”

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