A neurosurgeon for the Pittsburgh Steelers and medical consultant for the NFL believes chronic traumatic encephalopathy (CTE) is a "rare phenomena."

Appearing on NFL Network, Dr. Joseph Maroon -- who advises the NFL on head, neck and spine injury -- said the game "has never been safer" and downplayed the risk of CTE based on current data.

"I think the problem of CTE, although real, is it's being overexaggerated and being extrapolated to youth football and to high school football," Maroon said.

Maroon said he reviewed all known cases of CTE, a progressive degenerative brain disease related to head trauma and found in dozens of retired athletes in football and other sports, from 1954 to August 2013.

"We came up with 63 total cases of CTE [and] in the last two years a few more," he said. "But there have been 30-40 million kids who have played football during that period of time. It's a rare phenomena. We have no idea the incidence. There are ... more injuries to kids falling off bikes, scooters, falling in playgrounds than there are in youth football. I think again, it's never been safer. Can we improve? Yes. We have to do better all the time to make it safer."