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.