Rising fear about concussions sustained while playing contact sports has sparked a national debate among doctors over the safety of youth sports.

The Centers for Disease Control and Prevention estimates that about 173,000 children are treated for concussions from sports-related activities nationwide each year.

It's unclear what the long-term effects of concussions are for young athletes, but there's fresh alarm swirling around the damage to professional athletes' brains. However, some experts question whether the extent of the damage seen in adults is comparable to what young athletes might experience.

Front and center in the debate: chronic traumatic encephalopathy, or CTE. The progressive degenerative brain disease can be confirmed only after a person dies.

Studies of brains donated by the families of NFL players who suffered multiple concussions throughout their careers found CTE in 87 of the 91 deceased NFL players.

The forensic pathologist who discovered the suspected link between head trauma and CTE in NFL players is the subject of a new movie, "Concussion."

But some doctors caution against getting overly alarmed about concussion risks that come with playing any contact sport.

"The vast majority of people who have a single concussion or even two or three will recover completely," said Dr. Uzma Samadani, a neurosurgeon at Hennepin County Medical Center and author of a new book, "The Football Decision: An Exploration Into Every Parent's Dilemma on Whether or Not to Let a Child Play Contact Sports." She added that there is no "causative evidence" that a single concussion can lead to CTE.

Included in the other side of the debate are two University of Minnesota doctors who are calling for an end to school-based football programs in order to prevent concussions.

Drs. Steven Miles and Shailendra Prasad argue that youth tackle football should be club-based. They say having football in schools puts pressure on students to engage in a sport that has a high rate of concussions — and can cause serious health problems.

"A brain injury is a special thing," Miles said. "In high school you're talking about 650 head hits per season. High school football needs a timeout."

Dr. Bennet Omalu — on whom the "Concussion" movie is based — recently called for a complete ban on children's football and other contact sports, citing concerns about concussions.

Samadani, who is a neurotrauma consultant for the NFL and founded a company that makes a tool for diagnosing concussions, is among those who oppose such a ban.

"The problem is that it's a much more complex question than what they're making it out to be," she said. "Football is somewhere in the middle of the risk spectrum of what kids do. The riskiest thing is horse riding. Then there's skiing, skateboarding, unsupervised playground activity.

"If you're going to ban football, you have to look at this in the terms of why are we banning something in the middle of the spectrum. We should ban the worst. We should start by increasing the driving age."

Are pro athletes the model?

The majority of people who have an isolated concussion will recover, Samadani said, which is why managing the injury is crucial to allow the brain to heal before getting back in the game.

Adding its voice to the debate, the American Academy of Pediatrics has called to preserve tackle football while increasing flag football and noncontact alternatives.

Robert Doss, another local concussion expert, opposes a ban on football or any other youth sport to prevent concussions.

"I'm not in favor of it. The benefits of [playing] far outweigh the risks," he said. "It's an individual decision that a family and an athlete has to make. But I think we have more problems with childhood obesity and with injuries from motor vehicle accidents and drugs and alcohol than we do with concussions from participation in youth athletics."

Many of the fears that parents and others have about youth sports and concussions are based on information coming out about the injuries sustained by elite athletes playing for many years, he pointed out.

"The problem that we have right now is that all of the information that we have on CTE is on very select samples," Doss said. "For example, the Boston University group, they get these brains donated to them, and they're usually professional athletes who have had long careers in contact sports."

But Miles argues that there's legitimate reason to be concerned for amateur football players.

"What we know when we look at the brains of NFL players, 80 to 90 percent are showing concussive damage. There is a substantial level of kids who just play at the college level who are showing up with significant concussive damage," he said. "If this is showing up in college players, to say that it's not showing up because of high school play is whistling in the dark."

Girls more at risk than boys

While much of the concussion talk focuses on boys, it's actually the girls who are more at risk, research indicates.

The reason for female athletes being more vulnerable to concussions is unclear, but many concussion experts are now looking to another body part for the answer: the neck.

"There is this idea out there that strengthening neck muscles can potentially lead to fewer concussions. Because essentially what you're doing is making the head more rigid to the body so you're going to get less sway and less twisting and turning," said Doss, a neuropsychologist and co-director of the Pediatric Concussion Program at Children's Hospitals and Clinics of Minnesota. "There hasn't been a lot of research establishing this as a fact. I'm not aware of any research that has looked at a program of neck strengthening and whether it's related to fewer concussions."

Strength-training programs for the neck are increasing in youth athletic programs as awareness grows.

"Where some of this is coming from is this whole, the data that suggests that women and girls are more susceptible to concussions," Doss said. "One of the reasons may be that their neck muscles are not as strong as boys and men."

Allie Shah • 612-673-4488