Do you perform an x-ray (X-ray) on every child with a head bump after a fall?

X-Ray Evaluation for Children with Head Bumps After Falls

Not every child with a head bump after a fall requires an X-ray, but clinical decision-making should follow validated algorithms based on age and risk factors.

Age-Based Approach to Head Trauma Imaging

Children Under 2 Years

• For infants <3 months: More cautious approach needed as they have 0.4% risk of traumatic brain injury on CT and 0.9% risk of isolated skull fractures 1
• For children 0-11 months: Higher risk group with 29% incidence of skull fracture/intracranial injury vs. 4% for children 13-24 months 2
• For children <2 years: Use PECARN criteria to identify very low-risk patients:
  • GCS of 15
  • Normal mental status
  • No palpable skull fracture
  • No scalp hematoma (except frontal)
  • No loss of consciousness (or <5 seconds)
  • Non-severe injury mechanism
  • Acting normally per parents 3, 4

Children 2 Years and Older

• Use age-appropriate PECARN criteria to identify very low-risk patients:
  • Normal mental status
  • No loss of consciousness
  • No vomiting
  • Non-severe injury mechanism
  • No signs of basilar skull fracture
  • No severe headache 3, 4

Decision Algorithm

1. Very Low Risk (per PECARN): No imaging needed

   • 100% sensitivity and 100% NPV for clinically important TBI in children <2 years
   • 96.8% sensitivity and 99.95% NPV for clinically important TBI in children ≥2 years 4

2. Intermediate Risk: Consider observation vs. CT based on:

   • Multiple vs. isolated findings
   • Physician experience
   • Parental preference
   • Worsening symptoms during observation 3

3. High Risk: CT recommended

   • Signs/symptoms of intracranial injury
   • Skull fractures
   • Altered mental status 5

Important Considerations

• Skull radiographs are insufficient for evaluation as up to 50% of intracranial injuries occur without fracture 5
• Child abuse concerns: Lower threshold for imaging when mechanism is inconsistent with injury or suspicious 5
• Fall height matters: Even falls ≤3 feet can cause significant injury in 7% of cases 2
• Clinical signs are insensitive: 92% of children with isolated skull fractures and 75% with intracranial injury had normal consciousness and non-focal neurologic exams at diagnosis 2

Special Scenarios

• Suspected abuse: Clinicians should have a low threshold for performing head CT or MRI, especially in children under 1 year of age 5
• Infants <12 months: May have significant intracranial injury without signs/symptoms of head injury or retinal hemorrhage 5

Common Pitfalls to Avoid

1. Relying solely on skull radiographs for evaluation
2. Assuming minor falls cannot cause significant injury
3. Depending only on clinical signs/symptoms to rule out injury
4. Failing to consider age as a significant risk factor
5. Not recognizing that normal neurological examination does not exclude significant injury

Remember that while radiation exposure is a concern, the PECARN decision rules have been validated to safely identify children at very low risk of clinically important traumatic brain injury, allowing physicians to avoid unnecessary CT scans while ensuring appropriate evaluation of higher-risk patients.