PAPER 188: RANDOMIZED TRIAL COMPARING ARM FRACTURE RATES ON SCHOOL PLAYGROUNDS WITH EITHER SAND OR ENGINEERED WOOD FIBER SURFACES.

Abstract

Purpose: Sports and leisure is the second leading cause of severe childhood injury after road traffic. Severe fractures from school playgrounds are common and preventable. Falling height and impact absorbing surface determine risk. We compared two loose fill surfaces (sand versus engineered wood fibre) to determine arm fracture risk.

Method: Twenty eight elementary schools in the same urban public school board were scheduled for playground replacement and consented to random assignment of either sand (14) or wood fibre (14) beneath the new playground. Two and a half school years of injury data were collected. Arm fractures were defined a priori as the primary outcome of interest.

Results: 267,864 student-months of followup data were collected; 84824 with sand and 183040 with wood fibre. Schools complied (surface installed as randomized) for 73% of the total followup time. Fracture rates were 4.1 per 100,000 student months on sand playgrounds and 13.0 per 100,000 student months on wood fibre playgrounds (p=0.112, analysis adjusted for clustering). Time for play, counts of children playing, weather, and completeness of injury reporting did not differ between groups.

Conclusion: Children at schools with sand surfaces had a lower arm fracture rate related to playground equipment falls. Using sand surfaces instead of engineered wood fibre surfaces is a simple and effective way of reducing arm fractures from playgrounds. This is the only randomized trial we are aware of regarding playground surfacing, and the finding is novel.