They are known as the invisible injuries. They may not result in bruises, breaks, or even loss of limb but the results of concussions can be disastrous, leading to severe brain trauma as well as psychological and neurological disorders.
They are injuries that the NFL knows too well. Six out of 10 NFL athletes have suffered concussions and nearly one-third reported having three or more, according to a 2000 study conducted by the American Academy of Neurology. In a more recent study, conducted in 2007 by the University of North Carolina's Center for the Study of Retired Athletes, 20 percent of the retired athletes who recalled having three or more concussions suffered from depression.
But while the consequences are pervasive, the problem is not unique to athletes.
For General Raymond T. Odierno, chief of staff for the U.S. Army, concussions are often looked at as lesser injuries and are rarely discussed among his soldiers.
"We have to make them [the soldiers] understand that you have to come forward because it has to be treated," Odierno said.
For this reason, he and the United Service Organizations Inc. (USO) have partnered with the NFL to try and eradicate the stigma associated with head injuries. He met with NFL Commissioner Roger Goddell last month to discuss how a future campaign will play out.
As a former football player himself at West Point, Odierno says there are more similarities than differences between a soldier and an athlete and believes that the partnership will assist in changing attitudes about head injuries.
"There's a lot of things similar to sports and the army: the teamwork, not letting your buddies down, not letting your teammates down, not letting your infantry squad mates down. ... I think part of it is the stigma of not letting your fellow player down or not letting your fellow squad member down," he said.
There have been nearly 230,000 reports of traumatic brain injuries among the soldiers deployed to Iraq and Afghanistan, according to military figures. Head injuries have been linked to post-traumatic stress disorder in soldiers and a study done earlier this year found links between head injuries and a degenerative brain disorder known as chronic traumatic encephalopathy.
While the military puts its troops through rigorous tests before, during and after deployment, it is hoping to pool resources with the NFL to better its technology, improve its marketing, and expand its medical information.
Since Odierno and Goddell's meeting, a group of players, coaches, analysts, and doctors have met at the Pentagon. The first session included Pittsburgh safety Ryan Clark, Arizona receiver Larry Fitzgerald, and ESPN analyst Merrill Hoge while a meeting Friday sat players down with members of the Army and Marines.
Odierno expects for the formal campaign to be launched later this summer.
And while details of practical effectiveness have yet to be seen, Odierno hopes that the shared experiences of the servicemen and women and the athletes can spur collective change.
"I think that if they see somebody they know," he said, whether personally or know him from playing football willing to come forward, willing to say, 'I have a problem,' maybe it will make it easier for him to say he has a problem," he said.