More than 25,000 Canadian children are treated each year in emergency rooms for injuries suffered in playgrounds, according to new data reported in the Toronto Star.

Only cycling leaves more children seriously injured than their adventures on slides, monkey bars and jungle gyms.

The majority of the injuries are broken wrists, arms and elbows, but research also revealed a large number of serious head injuries, and even cases of strangulation.

"These aren't knee scratches; they're serious injuries that require emergency medical treatment — and in many cases hospitalization," said Alison Macpherson, an assistant professor in the department of kinesiology and health science at York University in Toronto.

Most children injured are in the 5-to-9 age group, and most injuries are due to falls — often from a considerable height and on a hard surface.