The femur

The femur is the most common traumatic site of orthopedic injury requiring hospitalization and it is also the most common site of extremity injury in abused children (1–5). It has received more attention in the child abuse literature than any other long bone. Differentiation between an inflicted and an accidental femoral fracture commonly poses a daunting clinical and imaging challenge, and a thorough familiarity with the various aspects of this subject is necessary to view the role of diagnostic imaging in the appropriate clinical context.

Between 1946 and 1952, Caffey and others described the association of femoral fractures with subdural hematomas (SDHs) in infants (6–8). Femoral fractures in infants were described in several other reports in the 1950s, and many of those accounts pointed to abuse as a possible cause of injury (9–15). The first chapter on these injuries came to a close with Kempe and colleagues’ grouping of these and other radiologic and clinical manifestations of child maltreatment under the concept of the “Battered Child Syndrome.”(16).

An early review of fractures cited in five large series of abused children revealed an overall prevalence of femoral fractures of 20% (17–22). Femoral fractures in infants have a strong association with abuse, whereas similar fractures in older children are usually determined to be accident (23–31). Beals and Tufts analyzed 80 femoral fractures in children under 4 years of age and found that 8.5% of the fractures were caused by violent (accidental) trauma, 12.5% were pathologic in nature, and 30% were caused by child abuse (24). The remaining fractures were the result of lesser accidental trauma to otherwise normal children. Femoral fractures secondary to abuse were found to be more common in children less than one year of age who were firstborns and had preexisting brain damage. The fractures, which were often bilateral, occurred with two peak age incidences: six months and three years.