Sports concussions make up a big part of that. But now a new law in New York State may change that.
The new concussion law is mandatory for public and charter schools in New York State.
It was created in 2011, but now for the first time it's in effect as of this school year.
School officials have said many parents don't know about it.
Michael Trinkoff finished out a soccer game 2 years ago despite having a concussion.
Under the new law concussion precautions are now mandatory.
The Concussion Management and Awareness act requires athletic staff members to complete a concussion training course every two years.
And students with a suspected concussion must be immediately removed from athletic activities. And for the first time, they can only return to play with written consent from a physician.
"The athlete automatically comes out-- whether it's suspected or actual they automatically come out,' said Tappan Zee High School AD Liam Frawley.
Frawley tells athletes they'll be out for at least a week.
But diagnosing a concussion is not black and white. So the new challenge is making that initial call, because once you make it you cannot go back.
And that has some students concerned
"I mean it's better to be safe and get checked out, but I mean if it's just something light, then they shouldn't," said Kerri Dillon.
At Tappan Zee High School, Gabrielle Kachur is the one making the tough calls on the field.
"It's hard to see every hit and signs of symptoms of a concussion overlap with multiple things," she said.
But she says with the new law to back her up, she has more freedom to err on the side of caution, even if parents and coaches are pushing to get the player back.
Once athletes get the ok from their doctor to get back in the game, they have to follow something called the Zurich Protocol.
It starts with light activity and gradually increases. But you can only move to the next level if you have no symptoms for 24 hours between each one.
LINK: THE CONCUSSION MANAGEMENT AND AWARENESS ACT
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