Non-Accidental Injury

Epidemiology

  • Uncommon
  • Crosses socio-economic and cultural boundaries
  • Probably under diagnosed
  • Important to recognise (but difficult)
  • Small proportion of children presenting with fractures
  • Commonly have occult fractures

History

  • Important to recognise (but difficult)
  • Risk Factors
    • Twins,
    • unplanned pregnancies,
    • lower socio-economic status,
    • children with special needs,
    • pre-term babies
  • Age – Younger more likely with key ages of less than 2 and 1
  • Developmental age
  • Mechanism
    • Appropriate behaviour
  • History of previous injury
  • Medical problems
  • Rare causes predisposing to fractures
    • Bone and mineral disease, Osteogenesis imperfecta

Examination

  • General findings
    • altered level of consciousness,
    • difficulty in breathing,
    • seizures,
    • failure to thrive.
  • Specific orthopaedic features
    • Assessment of
      • pain,
      • swelling,
      • deformity,
      • range of movement
      • altered function/ability to weight-bear
  • Bruising
    • Common in mobile children and in NAI
    • Most common clinical finding
    • Look for
      • away from bony prominences,
      • larger bruises,
      • Specific shapes,
      • multiple or clustered configurations

Fractures

  • Fractures with high specificity
    • Metaphyseal fractures
    • Rib fractures
    • Scapular fractures
    • Outer-end clavicle fractures
    • Fractures of different ages
    • Vertebral fractures or subluxation
    • Digital injuries in non-mobile children
    • Bilateral fractures
    • Complex skull fractures
  • Frequent fractures but with low specificity
    • Mid-clavicular fractures
    • Simple linear skull fractures
    • Single long-bone fractures

Long bones and NAI

  • Femur fractures – under 1
  • Tibia and fibula under 18 months
  • Any Humeral fracture under 15 months
  • Humeral spiral fractures commonly associated with NAI
    • Diaphysis 4 X more common than metaphysis
    • Epiphysis rare
    • Metaphyseal fractures are uncommon in infants
    • Think NAI

Metaphyseal fractures

  • Uncommon under 2
  • Indirect forces
    • Acceleration – deceleration
  • Associated in neonatal period
    • Classic corner and bucket handle #’s
    • Occur through the weak zone

Investigations

  • XRays
    • to confirm fracture
    • To rule out NAI
  • Blood Tests
    • Consider biochemical tests, tests for osteogenesis imperfecta
  • Skeletal survey
    • Periodic review and monitoring of callus formation
    • Experienced radiologist
  • Bone scan
    • Metaphyseal fractures
      • Poor sensitivity – growth
    • Diaphyseal fractures
      • High sensitivity
  • Dual modalities
    • Including CT should be considered

Conclusions

  • Literature is poor evaluating orthopaedic features of NAI
  • Retrospective studies = BIAS to NAI
  • Almost no quality comparative prospective epidemiological studies
  • Highlighted with metaphyseal fractures
  • High risk groups not studied appropriately
  • Multidisciplinary group

Take home message

  • Think about NAI
  • Involve pediatricians if concerned (multidisciplinary approach)
  • Non ambulant and children under 1 year with fractures
  • Multiple fractures
  • Fracture sights and patterns