Background <p>Epidemiological data on injuries and fractures in children under two years of age is limited, thus, we aimed to explore the incidence, patterns and mechanisms.</p> Methods <p>Retrospective, population-based cross-sectional study including children under two, seen at the A&amp;E department due to a trauma, or having a radiograph due to birth trauma. All radiographs were re-reviewed.</p> Results <p>Four hundred thirty children (49.8% female), mean age 14.7 months (SD 6.8), were included, of whom four had a high-energy trauma and 42 were birth-related. Of 388 children (50.3% female) (mean age 16.3 months, SD 5.1 months) with non-birth related injury, 163 (42.0%) had a fracture (annual incidence 4.3 per 1,000 children; 2.4 per 1,000 infants vs. 6.1 per 1,000 children aged 12 to 24 months of age. 47/163 (28.8%) fractures involved the forearm and 41 (25.2%) involved the leg. Fracture mechanisms 39.9% fall from more than own height/furniture; 17.2% fall from own height, 6.7% crush injury and 6.1% dropped by parent. In 12.9% of the traumas, no mechanism was provided.</p> <p>The number of fractures increased significantly by age group (<i>p</i>=0.027), and the distribution differed, with skull fractures predominating in 0-6-months-old (33.0%), clavicle fractures (33.0%) in 6-12-months-old and forearm fractures in the two older age groups (35.0% and 34.4%, respectively) (<i>p</i> &lt; 0.001). No classic metaphyseal lesions were found in the entire cohort. Four children, all of whom had radiological “red flags”, had inflicted injury. </p> <p>Forty-two children had birth-related injury, of whom 50.0% had a fracture (1.1 per 1,000 live births). </p> Conclusions <p>Fractures in infants are rare, in particular classic metaphyseal fractures. The occurrence of radiological “red flags” should raise suspicion of non-accidental injury and instigate further assessment. </p>