title: Atlas fractures.
abstract: OBJECTIVE
  To provide a comprehensive review of the biomechanics, pathophysiology, and clinical management of atlas fractures.
  
  
  METHODS
  Selected literature review.
  
  
  RESULTS
  Atlas fractures account for 25% of craniocervical injuries, 3% to 13% of cervical spine injuries, and 1% to 3% of all spinal injuries. Motor vehicle accidents account for 80% to 85% of atlas fractures, and the mechanism of injury is axial loading. Isolated atlas fractures are more common; however, 40% to 44% of atlas fractures have concomitant axis fractures. Fractures of isolated anterior or posterior arches are more common and typically seen with concomitant spine fractures. Isolated burst fractures are the second most common type and rarely cause neurological injury. Treatment of atlas fractures is based on whether they occur in isolation or in combination with other cervical spine injuries and on the integrity of the transverse ligament, which is best assessed with high-resolution magnetic resonance imaging. Isolated atlas fractures without injury of the transverse ligament or associated with bony avulsion of the transverse ligament can be treated with halo-brace immobilization and should be followed for instability with flexion-extension radiography. Surgical fixation is recommended for nonbony avulsion of the transverse ligament or if instability is present. The type of surgical fixation is determined by the concomitant craniocervical injuries if present.
  
  
  CONCLUSIONS
  Atlas fractures can be treated with halo-brace immobilization with acceptable outcomes. The role of surgical fixation, especially for atlas burst fractures, requires further study for clarification.
authors.affiliation: Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona 85013, USA.
authors.forename: Udaya K
authors.initials: UK
authors.lastname: Kakarla
authors.forename: Steve W
authors.initials: SW
authors.lastname: Chang
authors.forename: Nicholas
authors.initials: N
authors.lastname: Theodore
authors.forename: Volker K H
authors.initials: VK
authors.lastname: Sonntag
mesh_terms: D000063:Accidents, Traffic / Q000706:statistics & numerical data; D001268:Atlanto-Axial Joint / Q000293:injuries* / Q000473:pathology* / Q000503:physiopathology; D001269:Atlanto-Occipital Joint / Q000293:injuries / Q000473:pathology / Q000503:physiopathology; D001915:Braces / Q000592:standards; D001270:Cervical Atlas / Q000293:injuries* / Q000473:pathology* / Q000503:physiopathology; D002985:Clinical Protocols; D016267:External Fixators / Q000592:standards; D006801:Humans; D008022:Ligaments / Q000293:injuries / Q000473:pathology; D016103:Spinal Fractures / Q000473:pathology* / Q000503:physiopathology / Q000628:therapy; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods