Canadian researchers reviewing past research on the subject conclude that rules designed to curb aggression among hockey players - especially the tactic of slamming into another player, known as body checking - are linked with fewer injuries.

"It's pretty clear from what we know right now that if we institute rule changes that automatically tell people within that sport what's acceptable and what's not...that we can reduce injuries three- to 12-fold by doing that," said Dr. Michael Cusimano, lead author of the study and a professor and neurosurgeon at the University of Toronto.

Hockey is notorious for its fighting and physical contact.

And rates of reported concussions and spinal injuries have been rising among hockey players over more than a decade, Cusimano and his colleagues point out in the Canadian Medical Association Journal.

In many leagues, body checking is legal, but often has some limits, such as prohibitions against hitting a player from behind or in the head.

Some, but not all, studies have shown that body checking is linked with a higher chance of getting hurt (see Reuters Health report of June 8, 2010 here: reut.rs/WJJvDV).

To get a sense of what the research has found to be the most effective ways of curbing aggression in youth hockey, Cusimano and his colleagues collected the results of 18 studies.

Among them, 13 studied the effect of league rules to limit aggression, while three studies focused on education and two looked at the effect of behavioral therapy on managing aggression.

The educational and therapy studies found that interventions resulted in fewer penalties, but couldn't say whether this had any impact on the rate of injuries.

In seven of the nine studies that compared injury rates between leagues that allowed body checking and those that didn't, players were less likely to get hurt if body checking was outlawed.

One study, for instance, found a 12-fold difference in injuries between Pee Wee players in leagues that allowed body checking and those that didn't.

Cusimano said there need to be rules against aggression to keep young players safe, and they need to be enforced.

Alison Macpherson, an injury prevention researcher at York University in Toronto, who was not involved in the study, said others would argue that body checking is part of the game.

"There's a school of thought that if you reduce the age at which players start body checking, they will have learned how to do it before they're strong enough to cause damage," she said.

Studies have not backed that up, however, she added.

Some leagues have begun to tighten their rules against body checking.

Last year, for instance, USA Hockey, which governs amateur ice hockey in the U.S., moved up the age at which players can begin to use body checking from 11 to 13.

Macpherson said that in general hockey is a safe game that has made improvements in player safety.

"But they do play on a hard ice surface, so the potential for injury is always there. So I think we need to maintain the fun, maintain the sport, but keep it as safe as possible," she told Reuters Health.

SOURCE: tinyurl.com/bugvd3l Canadian Medical Association Journal, online December 3, 2012.

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