Out on a limb: Risk factors for arm fracture in playground equipment falls

Abstract

Objectives: To investigate and quantify fall height, surface depth, and surface impact attenuation as risk factors for arm fracture in children who fall from playground equipment. Design: Unmatched case control study. Setting: Five case hospitals and 78 randomly selected control schools. Participants: Children aged less than 13 years in Victoria, Australia who fell from school playground equipment and landed on their arm. Cases sustained an upper limb fracture and controls had minor or no injury. A total of 402 cases and 283 controls were included. Interventions: Children were interviewed in the playground as soon as possible after their fall. Main outcome measures: Falls were recreated on site using two validated impact test devices: a headform (measuring peak G and HIC) and a novel anthropometric arm load dummy. Equipment and fall heights, as well as surface depth and substrate were measured. Results: Arm fracture risk was greatest for critical equipment heights above 1.5 m (OR 2.39, 95% CI 1.49 to 3.84, p<0.01), and critical fall heights above 1.0 m (OR 2.96, 95% CI 1.71 to 5.15, p<0.01). Peak headform deceleration below 100G was protective (OR 0.67, 95% CI 0.45 to 0.99, p = 0.04). Compliance with 20 cm surface depth recommendation was poor for both cases and controls. Conclusions: Arm fracture-specific criteria should be considered for future standards. These include surface and height conditions where critical headform deceleration is less than 100G. Consideration should also be given to reducing maximum equipment height to 1.5 m. Improved surface depth compliance and, in particular, guidelines for surface maintenance are required.