Description: Atlanto-occipital dislocation: case report and discussion
David A. McKenna, MB, MRCOG, MRCPI, FFRRCSI;* Clare J. Roche, MB.BCh, BAO, MRCPI, DMRD, FRCR;* W. Kit Lee, MB.BS, FRANZCR;† William C. Torreggiani, MB.BCh, BAO, LRCP&SI, MRCPI, FRCR, FFRRCSI;† Vinay A. Duddalwar, MB.BS, MD, FRCR, DNB, MRad†
*Department of Radiology, University College Hospital Galway, Newcastle, Galway City, County Galway, Ireland†Department of Radiology, Vancouver General Hospital, Vancouver, BC
Received: June 7, 2005; final submission: Oct. 20, 2005; accepted: Nov. 9, 2005
This article has been peer reviewed.
Can J Emerg Med 2006;8(1):50-3
ABSTRACT
Atlanto-occipital dislocation (AOD) is a devastating condition that frequently results in prehospital cardiorespiratory arrest and accounts for 15% of fatal spinal trauma. Atlanto-occipital dislocation occurs 5 times more commonly in children than adults, and is believed to be caused by hyperextension. Because of improvements in prehospital resuscitation, more victims with AOD now survive to reach the emergency department. Neurologic injury is usually severe secondary to ligamentous disruption that allows the cranium to move with respect to the cervical spine, and associated facial and head injuries are common. There are, however, reports of survivors without neurologic deficits. We present the case of a 46-year-old woman who suffered an AOD after a motor vehicle crash and we discuss the diagnosis of this condition. The signs of AOD are often subtle, and the possibility of this diagnosis must be kept in mind in all patients with a neck injury, even in the absence of neurologic signs. A systematic approach to assessing the cranio-cervical relationship on the lateral cervical x-ray and the appropriate use of CT scanning is essential to identifying AOD. Through this case report we hope to familiarize clinicians with mechanisms of injury and appropriate imaging interpretation that will assist in the diagnosis of AOD.
