Hospital staff in Sheffield dealt with dozens of children being injured from trampolines.
In a six-month period, Sheffield Children's Hospital dealt with 198 patients with trampoline injuries - 130 using private equipment and 68 from indoor parks.
It found 44 per cent of those treated for injuries sustained at parks had suffered fractures, compared to 36 per cent for home trampolines.
The most common category for all trampoline injuries was 'bad landings' at 63 per cent.
Dr Catherine Rimmer, paediatric emergency medicine consultant at the hospital, told to the BBC: "There are a lot of trampoline parks that seem to be popping up all over the place that are neither regulated nor abide by basic safety precautions.
"I think the bigger parks are far better, but I know anyone can open a trampoline park in any kind of big open space and they're the ones parents need to be particularly careful of."
A higher rate of serious injuries at the country's booming trampoline parks than in private gardens has led to calls for the attractions to be regulated.
Ambulances were called to nearly 1,200 incidents at trampoline parks in England in 2017, while an audit at a major children's hospital found patients were more likely to have suffered a broken bone if injured at a park than at home.
A voluntary safety standard was launched in 2017 by members of the International Association of Trampoline Parks UK (IATP UK), British Standards and the Royal Society for the Prevention of Accidents (RoSPA).
Peter Brown, chairman of the IATP UK, told the BBC that the body would not be 'adverse' to regulation.
"The only way (regulation) would work would be the government setting legislation," he said.
"I can't see them doing that but if they did we would not be averse to that happening."