RT Journal Article SR Electronic T1 Trampoline-related injuries in children: a preliminary biomechanical model of multiple users JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 594 OP 598 DO 10.1136/emj.2009.085803 VO 28 IS 7 A1 Simon Menelaws A1 Andrew R Bogacz A1 Tim Drew A1 Brodie C Paterson YR 2011 UL http://emj.bmj.com/content/28/7/594.abstract AB Background The recent popularity of domestic trampolines has seen a corresponding increase in injured children. Most injuries happen on the trampoline mat when there are multiple users present. This study sought to examine and simulate the forces and energy transferred to a child's limbs when trampolining with another person of greater mass.Methods The study used a computational biomechanical model.Results The simulation demonstrated that when two masses bounce out of phase on a trampoline, a transfer of kinetic energy from the larger mass to the smaller mass is likely to occur. It predicted that when an 80 kg adult is on a trampoline with a 25 kg child, the energy transfer is equivalent to the child falling 2.8 m onto a solid surface. Additionally, the rate of loading on the child's bones and ligaments is greater than that on the accompanying adult.Conclusions Current guidelines are clear that more than one user on a trampoline at a time is a risk factor for serious injury; however, the majority of injuries happen in this scenario. The model predicted that there are high energy transfers resulting in serious fracture and ligamentous injuries to children and that this could be equated to equivalent fall heights. This provides a clear take-home message, which can be conveyed to parents to reduce the incidence of trampoline-related injuries.