What's the Diagnosis? By Dr. Michael Tom

A 29 yo male presents from a high speed MCV.  He was the unhelmeted driver of a motorcycle.  He was  unresponsive and intubated prior to arrival.  CT of the cervical spine is shown below.  What's the diagnosis?  Scroll down for answer



Answer:  Atlanto-occiptal dislocation (internal decapitation)



  • Most commonly from high energy mechanisms as in this case
  • Mechanism is hyperextension/distraction
  • Only about 1/3 of cases do not result in immediate death, and overall surival is rare
  • Children have a higher predisposition but also have a higher incidence of survival
  • Roughly half of the survivors will have residual neurological deficits
  • Lateral cervical spine xrays may be unremarkable aside froom pre-vertebal swelling
  • While presentation, as in this case, is usual not subtle, some patients may present awake and alert with complaint neck pain
  • CT plus MRI are used to evaluate ligamentous injury
  • CT angiogram is appropriate as concurrent vascular injuries are common
  • Early neurosurgical occipitocervical fusion is recommended, while traction/halo is not 




Nelson, A.  Traumatic Atlanto-Occipital Dislocation in Children.  Journal of the American Academy of Orthopaedic Surgeons. 2014; 22(5):275-282.

Tintinalli J, et al.  Tintinalli's Emergency Medicine: A Comprehensive Study Guide 8th Ed. New York: McGraw Hill Education, 2016.