Few playthings for children offer as much delight as trampolines, but the dangers they present should leave parents hopping mad, doctors say.
"The original intention of the trampoline was as a training device for acrobats and gymnasts. But what's happened is, it's become a backyard toy. And that's where things have gone wrong," says Dr Gary Smith, director of the Centre for Injury Research and Policy at Children's Hospital in Ohio.
"It was never intended for that purpose, and because of that it's simply unsafe," Smith says.
"The greatest number of trampoline-related injuries occurs among children ages 14 and younger," says Dr Paul Esposito, an APA spokesman who is an assistant professor in the paediatrics department at the University of Nebraska Medical Centre.
The most common injuries occur when children fall through the openings near the rim of the trampoline, land incorrectly or are thrown off balance by an upwardly moving trampoline mat.
"Arm and leg sprains, strains and fractures are the most common injuries," Esposito says. "However, severe injuries do occur and can result in paralysis or death."
"A child who falls on or off a trampoline will instinctively stretch an arm out to break the fall," he says. "If they land on an arm, they will probably break their elbow or forearm."
Many injuries result from more than one child using the trampoline.
"If the children are not jumping in unison, one could break a leg when the trampoline mat moves forcibly upward," Esposito says. "The smaller and usually younger child typically is the one injured."
Esposito adds that parents who own trampolines should also be concerned about other people's kids. "I think one of the things parents don't realise is the liability they have in having these things in their backyards," he says.
"If you have a pool, you know you have to have a fence around the pool because you can be liable if kids come in and drown," Esposito says. "Likewise, if you have a trampoline in your backyard that acts like a magnet for neighbourhood kids, you have to make sure to have a fence or have it continuously supervised, which is hard."
Adds Smith: "As an emergency medicine physician, I can tell you that every time the parents come in with their injured kid, the same words are said over and over - 'I can't believe this happened, I was standing right there and it happened right in front of my eyes and there was nothing I could do to stop it.' They're just devastated."