New guidelines from the American Academy of Neurology say no athlete who has had a concussion should be allowed to resume play until all symptoms have passed, revising earlier guidelines that allowed some athletes back on the field after just a week on the sidelines.
The guidelines, published in the journal Neurology, set the standard of care for doctors and follow studies that suggest even small blows to the head can have a big impact on brain health.
"We now understand that there are some really profoundly bad possible outcomes either from two hits in a row or a lot of hits over a lifetime," said Dr Jeffrey Kutcher, who chairs the sports neurology section of the American Academy of Neurology.
"There is evidence these injuries are more significant than we thought previously," Kutcher, a physician for the University of Michigan football team, said.
The issue of concussions in sports has been a hot topic recently in the United States in part due to violent hits by players in National Football League games. The NFL has taken new steps to protect its players from concussions, while sports teams at the college and high school level also have devoted more attention to the issue.
Kutcher is heading a push to revise guidelines for treating athletes with concussions issued in 1997, but he said the group is releasing preliminary recommendations now to help protect athletes.
Concussions an increasing concern
Earlier guidelines graded concussions based on whether they caused nausea, headaches or loss of consciousness or short-term memory. Athletes with mild concussions were let back on the practice field in a week.
"Those things really don't allow us to predict how long the injury is going to last," Kutcher said.
Concussions have become an increasing concern among professional athletes. The NFL said it would fine three players for dangerous hits - including helmet-to-helmet crashes - that violated player safety rules.
That has followed mounting evidence that repeated head injuries can damage the brain and even lead to early memory loss and dementia.
Under the new recommendations, Kutcher said athletes who have had a concussion will need to have a series of phased tests to make sure the brain is fully recovered.
Kutcher said estimates of the number of athletes who have had a concussion have been climbing in recent years, partly because more people are playing contact sports, young athletes are training more aggressively at an earlier age and doctors are more aggressive about diagnosing concussions, which 90% of the time do not involve loss of consciousness.
Often, concussions are not reported or caught.
In a study by researchers at Purdue University in Indiana, a team fitted 21 players at a local high school with special helmets equipped with sensors that monitored impact. They compared data from each player with brain scans and tests done before, during and after each season. And they shot video of each play to see how they were hit.
They identified 11 athletes who had been hit especially hard or repeatedly in the head. Of these, four were diagnosed with concussions. But an additional four had significant brain deficits that had not been diagnosed, they reported online in the Journal of Neurotrauma. (Reuters Health/ November 2010)
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