Background: The burden of childhood injury is often described using vital statistics for mortality and hospital admissions as a measure of morbidity. Hospital admissions, however, reflect the process of care and do not directly measure children's functional disability. The purpose of this study was to determine the influence of mechanism of injury on the functional outcome 6 months after injury in children in an inpatient trauma unit of a pediatric referral hospital.
Methods: A retrospective cohort of 357 children aged 2 to 15 with an Injury Severity Score (ISS) > 12 was studied to determine the relationship between mechanism of injury (based on International Classification of Diseases, Ninth Revision e-code) and functional outcome 6 months after hospital discharge. Wee Functional Independence Measure (WeeFIM) was used to assess functional outcome. Any child with a WeeFIM score less than the maximum (of 126) attainable was classed as requiring assistance, and the relative risk of requiring assistance at 6 months was calculated for each injury mechanism. Poisson regression analysis was used to assess the importance of mechanism of injury, after adjusting for age, gender, ISS, and a primary diagnosis of central nervous system (CNS) injury.
Results: Mechanism of injury had a significant effect on the functional outcome at 6 months: 72% of pedestrians, 64% of cyclists struck by cars, and 59% of injured motor vehicle occupants required assistance during daily activities. By contrast, only 27% of those injured playing sports and 22% of cyclists injured without motor vehicle involvement required assistance. The relative risk of children requiring assistance was similar with or without adjustment for age, gender, ISS, and CNS injury.
Conclusion: Mechanism of injury is significantly associated with requiring assistance 6 months postdischarge, even after controlling for age, injury severity, and the presence of a CNS injury. These data are important both when discussing the prognosis for an individual patient and also when considering the population impact of childhood injuries.