Is a buckle fracture to the distal left femur in a 3-year-6-month-old child concerning for child abuse?

Buckle Fracture of Distal Left Femur in a 3-Year-6-Month-Old: Evaluation for Child Abuse

A buckle fracture to the distal left femur in a 3-year-6-month-old child is not highly concerning for child abuse, but requires careful evaluation of the history, mechanism of injury, and other clinical findings to rule out abuse.

Risk Assessment for Abuse in Femoral Fractures

Age and Development Considerations

• Child's age (3.5 years) is important - approximately 80% of fractures caused by abuse occur in children younger than 18 months 1
• The child is ambulatory (typical for 3.5-year-old), which decreases suspicion for abuse compared to non-ambulatory children 1
• Femoral fractures are more concerning for abuse in non-walking children than in ambulatory children 1

Fracture Type Considerations

• Buckle fractures have low specificity for abuse compared to:
  • Classic metaphyseal lesions (CMLs)
  • Rib fractures (especially posteromedial)
  • Scapular fractures
  • Spinous process fractures
  • Sternal fractures 1

Key Elements in Evaluation

History Assessment

• Obtain detailed history of how the injury occurred 1
• Red flags in history that would increase concern for abuse include:
  • No history of injury
  • Implausible mechanism for the fracture type
  • Inconsistent or changing histories
  • Delay in seeking care 1
• Compare with typical non-abusive femur fracture histories, which often involve:
  • High-energy explanations (29% of cases)
  • Falls including stair falls
  • Siblings landing on the femur during play 1

Physical Examination

• Look for other injuries suspicious for abuse:
  • Bruising in unusual locations
  • Multiple fractures
  • Fractures of different ages
  • Other unexplained injuries 1

Imaging Considerations

• Initial radiographs of the distal femur are standard
• If abuse is suspected based on history or exam findings:
  • Skeletal survey should be performed in children under 2 years (not indicated in this 3.5-year-old unless other concerning factors) 1
  • Consider neuroimaging if there are concerns for head injury 1
  • Consider abdominal imaging if there are signs of abdominal injury or unexplained elevated liver enzymes 1

Decision-Making Algorithm

1. Assess mechanism of injury:

   • Is the reported mechanism plausible for a buckle fracture?
   • Common non-abusive mechanisms for buckle fractures include falls from standing/running, falls from bikes, or trampoline accidents 2

2. Evaluate consistency of history:

   • Is the history consistent among caregivers?
   • Does the history match the child's developmental capabilities?

3. Examine for other injuries:

   • Are there unexplained bruises or other injuries?
   • Are there multiple fractures or fractures of different ages?

4. Consider need for additional imaging:

   • If history is inconsistent or other concerning findings are present, consider additional imaging

Clinical Pearls and Pitfalls

• Pearl: Buckle fractures are extremely common in children and most are accidental 2, 3
• Pitfall: Focusing only on the fracture type without considering the entire clinical picture
• Pearl: The child's developmental status (ambulatory vs. non-ambulatory) is a key discriminator for abuse in femoral fractures 1
• Pitfall: Missing subtle signs of abuse by not obtaining a thorough history or performing a complete physical examination
• Pearl: Buckle fractures can be safely and effectively treated with soft casting with minimal follow-up 2, 4

In conclusion, while any fracture can potentially be caused by abuse, a buckle fracture of the distal femur in a 3.5-year-old ambulatory child is not highly concerning for abuse in isolation. However, the clinician must carefully evaluate the history, mechanism of injury, and look for other signs of abuse before making a final determination.