Preventing injuries on horizontal ladders and track rides.

Objectives: This study examined the type of injury, fall heights and measures of impact attenuation of surfaces on which children fell from horizontal ladders and track rides.

Method: All injured children who presented to two children's hospitals and received medical attention following a fall from a horizontal ladder or track ride in a public school or park during 1996--1997 were interviewed and the playground visited.

Results: The number of children who fell from horizontal ladders and track rides and presented to hospitals with injury was 118. Of those children, 105 were injured when they hit the ground and data were available on 102 of those playground undersurfaces. Fractures to the arm or wrist were the most common injury. The median height fallen by children was 1930 mm, 73% of injuries were from falls greater than 1800mm. In 41% of sites, the surface was deficient in impact absorbing properties for the height of the equipment. Fractures were no more likely on loose surfaces than other surfaces, such as rubber matting (p = 0.556) but more prevalent on compliant than non-compliant surfaces. Relative to falls occurring on noncompliant surfaces, the odds of a fracture occurring on a compliant surface was 2.67 (95% CI 0.88-8.14).

Conclusions: Modification of the height of horizontal ladders and track rides to 1800mm is preferable to removal of such equipment. The prevalence of fractures on compliant surfaces suggests that the threshold of 200g or 1000 head injury criteria (HIC) needs to be revisited, or additional test criteria added to take account of change in momentum that is not presently accounted for with either g-max on HIC calculations.