It may not seem like a big deal, but a new study says otherwise.
The report is in the Archives of Pediatrics and Adolescent Medicine and looked at young athletes with mild brain injuries.
It found that even if a child does not lose consciousness, he or she can sustain lasting symptoms and learning problems.
It's not hard to find the basketball player in this family.
15-year-old Gunther Starost has been shooting hoops since fifth grade.
But in January, he was whacked in the nose and then hit his head in a fall on the court.
That night, he drove home with his dad.
"I was in the car and my neighbor's house started to move and houses are not supposed to move, and that's when I knew something was up," Starost said.
Gunther had had a mild traumatic brain injury, a concussion where the brain is injured. It can happen even without loss of consciousness.
The new study showed these kids were more likely to have headaches and learning problems for months afterward compared to those with serious bodily injuries.
Gunther's still having headaches.
"Sometimes I won't be able to understand and recall things. I took a test the other day and I studied for 10 hours before and I couldn't remember a thing," Starost said.
"This can be without loss of consciousness and even with a normal MRI or CAT scan you can still have these symptoms," Dr. Stephen Thompson, of Hackensack University Medical Center said.
Symptoms can come with what appear to be minor head injuries, from hockey, soccer, especially for girls, football, even skateboarding and cycling.
Sports can teach kids a lot about life, but if there's a brain injury, when should parents step in?
It's often a tough judgment call.
"A second injury increases the risk, certainly multiple injuries, one has to consider whether it's worth continuing to participate in that sporting event," Dr. Thompson said.
Helmets can prevent trouble.
Amy Starost adds, speak to your kids.
"'How was your practice, how was your game?' communicate more. That was one of the big issues, kids don't want to tell you, 'I fell, what's the big deal?' but it really is a big deal," said Amy Starost, mother.
These seemingly minor injuries can cause issues that persist through life.
Dr. Thompson says it's opening a can of worms to talk about head protection for kids on the basketball court or soccer pitch, but prevention is certainly the best way to prevent the problem.
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