Trampoline park injuries have soared as the indoor jumping trend has spread.

That's according to a study that shows annual U.S. emergency room visits jumped 12-fold for park-related injuries from over five years. Injuries included broken legs, neck sprains and concussions but 90 percent of the injured children and adults were treated and released.

The study by researchers at Connecticut Children's Medical Center in Hartford was published Monday in Pediatrics . They analyzed a national injury database.

The American Academy of Pediatrics recommends against children using trampolines at home or parks and says injury rates at trampoline parks should be monitored.

THE NUMBERS

In 2010, there were 581 ER visits for injuries from trampoline parks versus 6,932 in 2014. During those years, the number of parks multiplied from 25 to 350 nationwide. Last year, there were 460 in North America, mostly in the U.S., and another 220 around the globe, the industry says.

Most trampoline injuries occur at home, not in indoor parks, and the researchers cite data showing that ER visits for home injuries were mostly stable during the study years, totaling about 60,000 each year.

WHO'S INJURED?

Two-thirds of the trampoline park injuries were in kids aged 6 to 17, while about 1 in 5 were in ages 18 and up. Only 14 percent were younger than age 6, while that age group accounted for 30 percent of those injured on home trampolines.

Injuries were most common in boys and whites.

INDUSTRY RESPONSE

The International Association of Trampoline Parks says the rate of injury is very low — less than one per 10,000 jumpers at a typical park. In a statement, the group said safety "is always a priority" and that it advocates supervision and protective padding. Many parks have padded walls.