Saturday, February 8, 2014

Do Helmets Help Prevent Concussions...

With the increasing attention being given to the potential dangers of concussions and repetitive head impacts, interest in helmet technology has increased also. While this attention has led to advances, it also has led to widespread misinformation about the ability of helmets to protect athletes from head injuries.

An understanding of the protective capabilities and deficiencies in helmets is the best way to ensure athletes have the correct information.

What Helmets Do Well

Helmets can be classified also as single-impact use or multiple impacts. For example, football helmets are designed for repetitive/repeat exposure, whereas most bicycle helmets are designed for only a single significant impact. In other words if you fall off your bicycle and hit your head that helmet should be discarded and replaced with a brand new one (never a good idea to buy a used helmet).  Team sport helmets are designed to protect against multiple head impacts typically occurring in the sport (e.g., ball, puck, or stick impacts; player contact; etc.), and, generally, can continue to be used after such impacts. (1) From my experience baseball helmets are often slammed to the ground out of game related frustration and take on a lot of general abuse being tossed around in the bench area. Paying close attention to this off the field wear and tear should be noted in addition to making yourself aware of manufacturer’s recommendations for replacement or reconditioning.

Laboratory data clearly show that helmets, including padded headgear, are generally good at distributing impact forces. This is a result of not only the impact absorption of the material but also the ability of the helmet to spread the force over a greater surface area. Helmets therefore have the potential to decrease injuries caused by such forces. These types of injuries include skull fractures, cerebral contusions, and intracranial bleeding. However because each head impact/injury is an almost infinitely unique combination of multi-directional forces, it can be difficult to extrapolate laboratory data to real-world safety. (2)

Football carries a significant risk of head injuries and accounts for the majority of sport-related catastrophic injuries in the United States. According to the National Center for Sports Injury Research, brain injury-related fatalities decreased from 128 (1961 to 1970) to 32 (2001 to 2010) (3). This number has been relatively stable, though slowly decreasing, since 1981 (3). This coincides with some improvement in helmet technology, but significant rule changes were also instituted in this time frame. The decrease in fatalities is likely related to both improved helmets and these changes, but it is unclear how much of the effect should be attributed to each. These injuries almost are seen exclusively in high school and college athletes. This most likely is due to the increased numbers of participants versus professionals.

Other helmeted sports, ice hockey, and to a lesser degree, rugby and soccer have generally overall lower risk of fatal or incomplete recovery. There are some data suggesting helmet effectiveness and no reported fatalities in Sweden since 1963 when mandatory helmets were introduced, but helmet introduction in hockey also coincided with an increase in facial injuries and concussion. It is unclear whether a more aggressive playing style (risk compensation) or increased attention may have led to this increase. There have been few direct head injury-related deaths reported since 1983 in high school or college ice hockey. There are little data on fatal or incomplete recovered head injury in soccer with the small number of soccer deaths almost all related to a goal falling over onto a participant.

What Helmets Do Not Do Well

There are two important anatomic issues that may limit a helmet’s ability to protect against concussive injury. First brain tissue has very little resistance and deforms easily to shear forces. An example of a shear force to the neck would be a football player that is hit form the side, his torso will travel in the direction of the hit while the head/neck tilt in the opposite direction of the force applied to the torso. Based on our current understanding of concussion, it is these shear forces that contribute most to concussive injury. Secondly the brain is a free-floating structure, making it susceptible to injury from these forces. (4) In other words the helmet offers little protection against shear forces and due to the weight of the helmet may even contribute to the shear stress.

Clinical data

Clinical data related to concussions can be difficult to interpret. Concussion rates have been increasing in recent years, and it is unclear whether this is a true increase in incidence or an increase in reporting. Given our increased awareness of concussive injuries and significant educational and legislative efforts, the increase is likely in large part a reporting difference. This does however make older studies on helmets and concussion difficult to compare, and these increased rates would suggest that modern helmets do not provide significant protection from concussive injury. This is consistent with the findings of several recent expert summaries on concussion (5,6).

Risk compensation

This theory suggests that the protective value of helmets, or any protective equipment, may be limited by the tendency of the wearer to increase risk-taking behavior while wearing the equipment. This theory is weakly supported by some data but it would be nearly impossible to prove it.

The value of any protective equipment is clearly limited by the circumstance under which it is used and whether the participants are willing to use it; however the effect of risk compensation on the protective effect of helmets seems logical and should shine a spotlight on the fact that coaches should always emphasize the importance of proper hitting/tackling technique and point out what a helmet was designed for (protection) and what it was not designed for (weapon/hitting aid). USA Football the developmental arm of the NFL has created the “Heads Up” program to help teach proper tackling technique and raise awareness for concussions at the youth level. It should also be noted that field/spatial awareness (“eyes on the back of their head”) and the ability of athletes to absorb impacts is just as vital for their protection. (7)

The Cool Factor

Major League Baseball has approved a padded cap designed to protect pitchers from potentially dangerous line drives. One issue however could be the size and feel of the cap.  The padding adds seven ounces to the weight of a cap, which currently weighs 3-4 ounces. The company does not believe the caps will interfere with a pitcher's motion or comfort adding that the best available stats indicate that 12 pitchers have been hit in the head by line drives during the past six seasons. Many pitchers feel differently or at the very least are skeptical:

Brandon McCarthy, who worked with the company as it developed prototypes and was also a pitcher that was struck in the head by a line drive and suffered a serious head injury, proved how tough a sell this could be for Major Leaguers when he told that the model he had tested was "too big" and "didn't pass the eye test" and was "too hot."

Blue Jays left-hander J.A. Happ, who suffered a fractured skull when struck by a line drive last May 7, was also non-committal.

"I'd have to see what the differences in feel would be -- does it feel close enough to a regular cap?" Happ told ESPN. "You don't want to be out there thinking about it and have it take away from your focus on what you're doing."

National League CY Young Award winner Clayton Kershaw told MLB Network that he also has some reservations, although he's optimistic that baseball is moving in the right direction.

"I've actually tried one of those on," said Kershaw. "I've thrown with it. You don't look very cool. I'll be honest. You don't look very cool out there.” (8)

In other words this cap has no chance at sticking in Major League Baseball unless it’s mandated.


Helmets have shown the ability, both in the laboratory and clinically, to decrease the risk of serious head injury in some circumstances. Because of study design limitations, the magnitude of this protection is difficult to quantify. Current data do not suggest that modern helmets are protective against concussive injury.

Phil Loomis
Youth Athletic Development/Nutrition Specialist

Related Topics

NFL Players would prefer head injury to knee injury

USA TODAY Sports surveyed 293 players on 20 NFL teams and asked what body part they were most concerned about injuring in a game:

-46% said knees or other parts of their legs
-24% said head and neck
-26% said none

The results seem surprising given all of the emphasis the NFL and the culture at large have given to the life-altering dangers of concussions in recent years.

“Anytime you can avoid hits to the head it’s great,” Chicago Bears running back Michael Bush said, “but if you get hit in your knees, that’s your career.”

You know what’s even crazier? The USA TODAY Sports survey also asked players whether NFL rule changes on hits to the head had made the game safer:

-39% said they had
-53% said safety was about the same
-8% said the game was less safe

“Heads Up,” is it nothing more than NFL propaganda?

Participation in youth football has been on the decline largely because many parents feel it is unsafe for their children. (9) Many critics think this program is the NFL’s attempt at image control and protecting the long-term interest of its brand. Learn more here:

Detecting concussions in young athletes, there’s an app for that!

GE and the NFL have teamed up to potentially make concussion detection more precise. Unlike traditional concussion screening methods, which require cumbersome equipment or medical training, take a long time to administer and are prone to manipulation by athletes, this patent-pending technology can be run on a mobile device and recognizes the changes in speech acoustics that occur with concussions. The result is a more objective, highly mobile concussion screening test that takes only two minutes to perform and can protect athletes from the danger of repeated concussions.

Study reveals this soccer population is the most vulnerable to concussion


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