Bone Abstracts

Objectives: Fractures in older children are common, often related to physical activity. In contrast, fractures in infants are rare and especially those involving the femur (upper leg) are infrequent. Femoral fractures in young children are highly suspicious for non-accidental trauma, and screening for possible child abuse should be urgently carried out. However, some metabolic bone diseases, like osteogenesis imperfecta (OI), may predispose to fractures already in infancy and should be differentiated from child abuse. The aim of this study was to characterize and compare the femoral fracture pattern in the overall infant population and in infants with known OI.

Methods: We carried out two retrospective studies on children with femur fractures before the age of one year. The population-based cohort (I) comprised all fractured infants from the city of Helsinki, Finland, during the years 1998–2012. The other cohort (II) involved all children with severe or moderate OI from Finland who sustained a femoral fracture during infancy in 1990–2012. Details regarding patient demographics, fracture type, and trauma mechanism were collected. All fractures were confirmed radiographically.

Results: In total there were 55 femoral fractures in 51 infants, of whom 14 were infants with OI. Four children had two separate fractures before the age of one year, all with OI. The girls to boys ratio was 1:0.9. The annual incidence for Helsinki was 4 per 10 000. Median age for fracture was 7 months for cohort I and 5 months for cohort II. The most common cause for the femoral fracture was a fall from height for cohort I whereas for OI infants in most cases no clear trauma could be identified. Location of the fracture was more proximal for OI and distal for non-OI patients. In six cases the OI diagnosis was set only after the femoral fracture.

Conclusion: We observed overlap but also some differences in femoral fracture pattern for infants with and without OI. The role of non-accidental trauma as fracture mechanism, more detailed trends, and other contributing factors remain to be elucidated in further analysis of the data.

Grants: Päivikki and Sakari Sohlberg Foundation, Foundation for pediatric Research, Sigrid Juselius Foundation, all Helsinki, Finland

Disclosure: The authors declared no competing interests.