AOD

FACTS

Internal decapitation 2/2 ligamentous injuries. Patients can present intact (20%), paralyzed, or dead.
  • more common in peds (higher head to body ratio, less cupped condyles, increased ligamentous laxity)
  • tectorial membranes and alar ligaments primarily responsible for resisting distraction between O and C1

Traynelis classification

1 - forward
2 - up
3 - backward
notion image

HPI

Clinical manifestations can range from intact to paralyzed to dead
  • minimal deficits
  • cruciate paralysis / bulbar cervical dissociation (immediate pulmonary/cardiac arrest)
  • can be fatal (respiratory arrest)
PHYSICAL EXAM
spine exam + lower cranial nerves

IMAGING

obtain CT C-spine, XR Cervical
All patients: BAI/BDI, ADI, Condylar gap (CCI=AOI), Powers ratio
Peds: C2 prevertebral soft tissue, lateral mass interval
BAI / BDI (normal (BDI) is 10mm adults, 12mm peds)
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Condylar gap (CCI) = AOI
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Powers ratio (BC/AO)
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A/P