As the minor hockey season shifts into playoff mode across British Columbia, there is yet more alarming medical evidence of the extent of the brain injuries that Canada’s game inflicts on kids.

According to a new research paper, young, otherwise-healthy male hockey players who had suffered a previous game-related concussion were given brain scans, which revealed consistent, detailed evidence of structural damage.

“We believe that injury to a developing brain may be more severe than injury to an adult brain,” the paper’s co-author, James Hudziak, a pediatric neuro-psychiatrist at the University of Vermont’s College of Medicine told the journal Diagnostic Imaging.

Symptoms among otherwise healthy athletes and evidence of concurrent brain changes are linked “to participation in a full-contact sport that involves frequent blows to the head” — in this case, hockey — said the researchers.

Other studies in Minnesota tracked injuries to minor hockey players over a 16-year span. Unsurprisingly, injuries to limbs proved most common. Traumatic brain injury ranked second. Almost one in four injuries required major medical interventions. Eight of every 100 injured players required intensive care.

“Most injuries resulted from intentional contact,” said the research team, which included medical scientists from the world-famous Mayo Clinic.

These studies amplify work by University of B.C. neuroscientist Naznin Virji-Babul.

Virji-Babul used brain scans to study previously concussed athletes. Most of her sample involved hockey injuries. She found that injury-related changes in the brains of adolescents suffering concussions persist far longer than previously assumed. This suggests much lengthier recovery periods from youth hockey concussions may be needed, and implies risk of serious long-term consequences for developing brains.

We already know that serial concussions in professional athletes precede cognitive disabilities, personality changes, attention deficit and anger management disorders, depression, and dementia. If this process begins with brains injured in minor hockey, it is imperative that authorities responsible for the safety and wellbeing of children and youth address it directly.

The American Association of Pediatricians is blunt.

“Boys who play ice hockey in leagues that allow body checking are two to three times more likely to suffer injuries and concussions compared to boys in non-checking programs,” the professional medical organization said. “This statistic points out a preventable harm in a sport that has the potential to be a lifelong activity for children.”

The research is conclusive, the pediatricians said. To protect children playing hockey from largely preventable brain injuries that might negatively affect their entire subsequent lives, often without the injured person being aware of the damage and its effects, bodychecking should be banned from all hockey to a minimum age of 15.

Fifteen was chosen because of frequent discrepancies in size and athletic skills for players below that age. At 13, some boys have not yet begun puberty, the researchers said, while some 14 year olds began puberty at 11 and are bigger, faster, heavier, more aggressive and more capable of inflicting injury with bodychecks.

But the researchers say hockey officials should seriously consider extending non-checking programs to ages above 15, and that where bodychecking isn’t eliminated far stricter rule enforcement at all hockey levels is needed to prevent contact from behind, into and near the boards.