The latest research says concussion symptoms disappear but the damage can't be seen.
Boys in Pop Warner football are growing faster, getting stronger and hitting harder at earlier ages. But their brains aren't becoming any tougher.
Vernon Williams, a neurologist and expert on sports-related concussions, says head injuries in youth football can't be treated like any other injury.
Williams said adolescents are at greater risk of some of the consequences of concussions than adult athletes. A youth's brain is still in the process of development, so it can't sustain the same kind of traumas and it doesn't recover as quickly as an adult brain does, Williams said.
"The sheer ability to sustain some of these impacts is much different in an adolescent and we've seen that recovery takes longer in youth athletes than it does in an adult athlete," Williams said.
Williams practices neurologic consultations and sports neurology at Kerlan-Jobe Orthopaedic Clinic in Los Angeles, a nationally recognized sports medicine clinic. Kerlan-Jobe has team physicians for the Los Angeles Lakers and Los Angeles Dodgers, the Kings and Ducks as well as USC.
Williams is also the medical director at the Sports Concussion Institute, a collective of neurologists, neuro-psychologists and consultant neuro-surgeons dedicated to the issue of concussions.
Williams and his colleagues have conducted thousands of baseline cognitive tests of athletes at every level and in every sport. They've also participated in the early concussion conferences that the NFL required three years ago.
Institute members have also spoken at national summits on concussions for each of the last four years on the latest issues. The goal of the institute is to bring the latest research information about concussions to all levels of sports, especially youth sports.
Although a certified athletic trainer attends the Pop Warner games Redondo Beach participates in, most youth football games do not have such medical supervision on the sidelines, Williams said.
Williams said the new Pop Warner rule prohibiting kids who suffer a concussion from returning to play without clearance by a doctor is needed because athletes, even young athletes, tend to under-report their injuries.
"They know what it's like to be tough, hang in there, shake it off, walk it off," Williams said. "You can't walk off a concussion. There are changes that occur in the brain when the brain is injured and you can't undo those changes more quickly because you're tough."
Sometimes athletes actually do think they are fine. They actually don't have any more headaches, their dizziness has disappeared, and they don't have any more nausea. But that doesn't mean the brain has healed or that the brain is ready for return to play, Williams said.
Doctors used to assign grades to concussions, with grade one being a concussion in which everyone—the trainer, athlete, coach—agreed that the symptoms were gone within 15 minutes.
"It was the classic where you got your bell rung," Williams said. "After fifteen minutes everything went away, you were fine."
As long as the symptoms cleared within 15 minutes, athletes have traditionally returned to action after getting their bells rung. However, neurologists began looking in more detail at brain function in athletes where everyone would agree was a grade-one concussion. They found that verbal memory, reaction time, speed of mental processing and visual memory didn't recover for five to seven days.
"So what we thought was an athlete who had a transient change in brain function, we realized wasn't true," Williams said. "The brain hadn't recovered, and it was still not functioning normally. If we looked close enough we found the brain wasn't healed and it wasn't returned to normal. So how could we say it was fine to go back (into a game)," Williams said.
Following a concussion, there's a period of what's call injury induced vulnerability. The brain changes when the injury occurs. The blood flow decreases immediately after a concussion whereas the fuel requirement increases.
"So there's this mismatch," Williams said. "The brain can't keep up. It either happens or it doesn't happen. Once it happens, there is a period of days for that mismatch to resolve. We know that from animal data but we can now see it in clinical data in humans. "
During the period of vulnerability, the athlete must be protected from another concussion because a second concussion could have catastrophic effects, including death from brain swelling.
"It's a rare consequence, but it happens and it happens much more frequently in adolescent and youth athletes than in adults athletes," Williams said.
The long-term consequences of concussions are less clear and still being studied, Williams said, including dementia and cognitive problems and depression.
Researchers do agree about the risk of multiple impact head injuries for players that return to action too quickly. Returning to action too soon exposes a boy to something called second-impact concussion, which can cause prolonged symptoms.
In adolescents, those include difficulty with memory, mental processing, personality disorder, headaches and pain.
"Even the NFL, where there are no documented episodes of second-impact syndrome or deaths on the field because of head injuries, even there if you have a concussion, you can't go back and play in the game because this is serious," Williams said, adding he saw a study a couple months ago that showed that 16 percent of high school athletes who had lost consciousness during a game retuned to play in the same game.
"That's just unacceptable," Williams said.
The risks of injuries from repeated concussions is something professional trainers understand. It hasn't been fully accepted at the lower levels, Williams said, and that is at least in part because there hasn't been the same kind of exposure to the information.