THE PREVALENCE OF NON-ACCIDENTAL INJURY IN TODDLERS WITH FEMORAL FRACTURES - THE CALGARY EXPERIENCE

The purpose of this study was to determine the prevalence of non-accidental injury in toddlers (birth to two years old) presenting with a femur fracture to a single institution within a Western Canadian population. There are currently no Canadian studies that investigate this association in the medical literature. A retrospective case-control study was performed for children less than or equal to two years of age with a diagnosis of femur fracture who presented to a single institution from 1994 to 2005. Patients with associated pathological or metabolic bone disorders were excluded. The primary outcome measure was the prevalence of non-accidental injury associated with femur fracture. Secondary outcome measures included: patient demographics, injury characteristics, radiologic and other work-up, and suspicion of abuse. Statistical analysis was performed using tests of analysis of variance and multivariate analysis to identify independent and significant risk factors associated with non-accidental injury. One hundred twenty-seven children that met the inclusion criteria were identified. The overall prevalence of non-accidental injury was 11% (14/127 patients) and 17% (10/60 patients) in children under twelve months. Mean age was twelve months in the abused group and sixteen months in the accidental group. Forty-three percent of the abused group had delayed presentation compared to 8% of the accidental group. In the abused group, 43% had unknown, unwitnessed, inconsistent histories versus 4% in the accidental group. No specific fracture pattern or location suggestive for non-accidental injury was identified. Forty-three percent (6/14 patients) of the abused group and 12% (13/113 patients) of the accidental group had other injuries. Multivariate analysis determined that delayed presentation (p=0.001), mechanism of injury (p=0.02) and other associated injuries (p=0.003) were the only independently significant risk factors for abuse. Toddlers who present with femoral fracture are at risk for associated non-accidental injury though perhaps this risk is not as high as previously thought. Regardless, a high index of suspicion is mandatory when these children are encountered and careful screening with a thorough history, physical examination, and other investigations where indicated, are warranted to rule out associated child abuse.