Dating long bone fractures of infants under one year of age.

Infants under one year of age frequently suffer from inflicted fractures. Dating the trauma is vitally important to identify the perpetrator and ensure the protection of the child. While several studies have investigated the radiological dating of fractures in children, few have focused specifically on those occurring during the first year of life. Although maltreatment is particularly common in the first few months of life, dating these fractures remains challenging, as bone healing capacity is age-dependent and may differ from that observed in older children. In addition, the radiological nomenclature found in the literature is heterogeneous and often imprecise.The aim of this study was to apply clearly defined radiographic criteria to establish an analytical methodology that facilitates the dating of long bone fractures in infants under one year of age. A total of 99 infants under one year old with long bone fractures of known date were included, representing 290 radiograph sets. Four dating groups were defined based on literature data, with the aim of developing predictive models based on well-defined radiographic features, in order to construct a simplified dating decision tree.Our findings suggest that the absence of periosteal apposition and bone remodeling is consistent with a fracture less than one week old. On the other hand, the presence of periosteal apposition suggests a fracture that is probably one to eight weeks old, and more than one month old when accompanied by signs of remodeling. Finally, isolated signs of remodeling are suggestive of a fracture of more than two months.