Companies redesign football helmets to reduce concussions
Tuesday, November 10, 2009
Blake Lawrence tried not to think about injuries when he was on the football field. But Lawrence, a junior who until recently played linebacker at the University of Nebraska, could have been forgiven for worrying about his head. In one 12-month span, from spring 2008 to spring 2009, three on-field blows left Lawrence with a trio of mind-numbing concussions.
Two were the result of helmet-to-helmet collisions with teammates in practice. The other he suffered while taking down a Kansas State running back last fall.
In all three instances, the blows, all near his left temple, left Lawrence in a "state of total confusion," unable to comprehend plays or answer questions.
"My brain just got rattled," Lawrence said.
With his football career -- not to mention his health -- in jeopardy, Lawrence looked for sturdier head protection before taking the field this fall. In consultation with his family and Nebraska's medical staff, he selected Xenith's X1, a helmet with an innovative design of air-cushioned shock absorbers that hit the market last November. A range of trainers, coaches, head injury experts and equipment gurus think that the new design holds promise but agree that only longtime use in real games will show how well it works.
"It's helped me this year not only be safer, but feel safer," Lawrence said a few weeks ago. After a big hit during Nebraska's second game this fall, Lawrence said he "took inventory," checking to see "if I got all my screws together up there. I ended up being okay. . . . I think it has protected me pretty well."
Football helmet manufacturers face a unique design challenge. Whereas motorcycle helmets, for example, are meant to be discarded after one severe impact, football helmets must be soft enough to cushion routine blows, stiff enough to absorb the force of violent helmet-to-helmet collisions and durable enough to withstand week after week of intense punishment.
A far cry from the leather headgear of the early 1900s, most modern football helmets are stiff polycarbonate shells lined with dense foam padding. They're designed to protect players from such potentially deadly injuries as skull fractures and subdural hematomas and have been very effective at doing so. They are often unsuccessful, though, at preventing the concussions and other damage, often cumulative, that comes from less dramatic collisions.
Xenith seeks to provide protection against both routine and extreme blows by replacing the traditional foam with a "shock bonnet": an adjustable cap housing 18 plastic shock absorbers shaped like small hockey pucks, each of them hollow with a tiny hole on top.
When a player wearing an X1 takes a relatively mild hit, the pressure forces air out of the pinholes, dispelling force by deflating the absorber until it's as flat as a saucer. When the pressure is removed, the absorbers reinflate quickly -- much as the bulb of a turkey baster pops open when you stop squeezing -- and the helmet is ready for the next impact.
During a more violent collision -- say, a high-speed, helmet-to-helmet blow on a kickoff -- the higher level of force tries to displace the air more quickly than the pinhole can accommodate, thereby increasing the air pressure inside the absorber. That pressure stiffens the disk, offering skull protection much as traditional helmets do. (Think of a bicycle-tire pump: Pump forcefully and the handle becomes increasingly hard to push down. Apply pressure slowly and you meet less resistance.)
It's during the milder, routine impacts that Xenith's forgiving cushion may offer a significant advantage, experts say. Gerard Gioia, a neuropsychologist who leads the concussion program at Children's National Medical Center, said the gradual expulsion of air would spread the force of impact over a longer period of time, lessening the force that reaches the brain.
"We want to have a helmet that responds differently in every impact," said Dave Halstead, technical director at the National Operating Committee on Standards for Athletic Equipment, an independent group that certifies football helmets worn from the youth to professional levels.
Although he describes Xenith's approach as unique, he is not convinced that any manufacturer has solved the concussion problem. "Anyone who says to you that they have a helmet that eliminates concussions is lying to you," Halstead said, because the most likely cause of most concussions is not the blunt linear force of impact, but the resulting rattling of a player's brain inside the skull. Consider that a player can sustain a concussion without so much as a visible bump on his head, Halstead said. It's like shaking a raw egg, he said: You can scramble the yolk inside without cracking it.
"Can helmets reduce or mitigate those rotational forces? . . . We don't know yet," Gioia said. "We'll see how this goes with Xenith and with other companies that are trying to address this problem. It's not a simple process."
The Centers for Disease Control and Prevention estimates that each year, 1.6 million to 3.8 million sports- and recreation-related concussions are sustained in the United States, many of them on football fields. Memory loss, confusion and nausea are among the immediate symptoms.
Scientists are studying the longer-term, cumulative effects. At Boston University, researchers studying the brains of several deceased professional football players with a history of head trauma found a degenerative brain disease linked to paranoia, aggression and progressive dementia. And a recent study commissioned by the National Football League found that former players ages 30 to 49 were many times more likely than their peers to have received diagnoses of dementia and other memory-related diseases.
All football helmet manufacturers (Riddell, Schutt Sports, Adams and Xenith being the ones that supply to the NFL) have been tweaking helmet designs in attempts to combat football's head injury problem. Adams lines its helmets with foam of varying degrees of density to moderate the force of both routine and more extreme blows. Riddell has marketed a helmet that sends a wireless alert to a team's training staff if a player sustains a potentially dangerous impact.
Lowell, Mass.-based Xenith, founded by Vin Ferrara, a former Harvard quarterback, won certification from the standards committee in 2007 for the X1 helmet. The company gave away 2,000 helmets in 2008 and has sold about 15,000 in the past year, according to company spokesman Chris Clark. The majority are being used at more than 600 high schools across the country, including, in the Washington area, Walt Whitman, Landon, Broad Run and Oakton. It's also in use at Princeton University, North Carolina State University and the University of Illinois.
NFL players who are trying it include Ryan Fitzpatrick and Xavier Omon of the Buffalo Bills, the Indianapolis Colts' Dallas Clark and the Baltimore Ravens' Matt Birk. (Birk, a center, is one of three professional players who recently pledged to donate their brains after death to Boston University's Center for the Study of Traumatic Encephalopathy for the study of head injuries.)
"I think the shock-absorption system is the best out there," said Charlie Thompson, the head athletic trainer at Princeton, where 20 football players wear Xenith helmets. Thompson said Princeton players sustained 12 concussions last fall and six so far this fall, with just one involving a player wearing a Xenith. "I am very pleased with the protection it's provided."
At Nebraska, where Lawrence has been the only player wearing the X1, Mark Mayer, the head football trainer, sees potential but remains skeptical.
"It's something I'm going to keep my eye on," said Mayer, a former assistant trainer for the NFL's Oakland Raiders. "If there's anything out there that's going to protect our players . . . we're going to explore it. It's such a young product. Is it better than what's out there right now? We just don't know yet. But it does hold promise."
Like Halstead, some experts suspect helmets, however advanced, cannot prevent the cause of most concussive incidents. They suggest the best defense against concussions might just be simple education and prevention. Players should not put such trust in their helmets that they use their heads as battering rams, for example. And if they feel abnormal after a big hit, they should resist the urge to shake it off and keep playing.
Despite his hopes for the X1, Lawrence has come to a similar conclusion. While wearing the new helmet in a recent tackling drill, he was left confused and anxious after another blow near his left temple. "I knew my head wasn't working right," Lawrence said. "For the rest of practice, I spent a lot of time staring at the ground in front of me, trying not to focus on faces. I was just out of it."
It was his fourth concussion in less than two years. "I put no blame on the helmet at all," he said. "My head is just more prone to being rattled."
But after giving it some thought, Lawrence took a major step: He decided to quit football.
"My brain works pretty well," he said. "As long as I'm not taking continuous hits to the head, it will stay that way."