While the number of Canadian hockey injuries requiring treatment in an emergency room is falling, serious injuries due to body checking are on the rise, particularly among children, according to new data.

The findings suggest that a decision by some minor hockey associations in Ontario to allow full body contact in players as young as 9 has resulted in hundreds of more serious injuries, and is bound to reignite debate about the age at which checking is safe.

"The issue of body checking in youth hockey requires a good hard look," said Alison Macpherson, a professor of kinesiology at York University in Toronto. "Playing hockey should be fun, it shouldn't be sending so many kids to hospital."

The data, compiled by the Canadian Institute for Health Information, show that 21,708 people were treated for hockey injuries in Ontario in the fiscal year 2003-2004, a 5-per-cent decrease from the previous year.

But the number of body-checking injuries rose to 6,748 in the same period, a 5-per-cent increase.

Dr. Macpherson, who is an expert in injury prevention, said more noteworthy than the overall numbers is the concentration of checking-related injuries among children. "You see this real peak in atom and peewee, ages 10 to 14. I find the numbers there quite high," she said.

A total of 2,329 children aged 10 to 14 were treated in Ontario hospitals last year for injuries related to body checking.

Hockey Canada policies now allow players to body check beginning at age 11, though the starting age is 9 in four of the largest hockey associations in the country, which are concentrated in Ontario. Hockey Canada had lowered the checking age to 9 in 2002 but reversed itself after a public outcry, and revelations that research used to justify the change was flawed.

However, most injury-prevention and medical groups believe the restrictions on bodily contact should be more severe.

Both the Canadian Academy for Sports Medicine and the American Academy of Pediatrics have policies stating that body checking should only be allowed after the age of 15.

Overall, the most common type of hockey injury is superficial -- cuts and bruises -- accounting for 43 per cent of the total. Next are orthopedic injuries, such as broken arms and wrists, at 31 per cent, and head injuries at 4 per cent. There were also some serious injuries recorded in the data, including 53 internal injuries, 10 spinal-cord injuries, nine cases of a major blood vessel being severed, and six cases of severed nerves.

Only about 4 per cent of those treated for hockey injuries needed to be hospitalized. But body-checking injuries accounted for one-third of hospitalizations.

According to the data, 35 per cent of injuries were due to hitting an object such as the boards, 31 per cent were due to body checking, 17 per cent were caused by being hit by a stick, and 17 per cent were due to being hit by a puck.

More than 93 per cent of all hockey injuries are suffered by boys and men, and less than 7 per cent by girls and women. More than four million Canadians play hockey, and at least 500,000 young people play in organized leagues.