title: Occipital condyle fractures.
abstract: OBJECTIVE
  Occipital condyle fractures (OCFs) are infrequently recognized. Three recent cases of OCF in our center prompted a review of the incidence, clinical presentation, diagnosis, and treatment of this entity.
  
  
  METHODS
  A retrospective review of medical records and radiographic results was performed for 93 of 316 consecutive patients who were victims of trauma, who presented at the Toronto Hospital during a 13-month period, and who had undergone computed tomography of the occiput.
  
  
  RESULTS
  A review of the literature regarding OCF revealed that cranial nerve deficits occurred in 31% of the patients with OCFs; of those, the deficits were delayed in 38%. Three new cases of OCF, with neck pain but without cranial nerve deficits, have been reported. The cervical spine x-rays revealed nothing abnormal in 96% of the reported cases. In our retrospective review, asymptomatic OCF was revealed by computed tomography for 1 of the 93 patients.
  
  
  CONCLUSIONS
  OCF is a diagnostic challenge. We suggest that computed tomographic scans of O-C2 be obtained in the following circumstances: presence of lower cranial nerve deficits, associated head injury or basal cranial fracture, or persistent severe neck pain despite normal radiographic results. We propose a new classification system for the management and treatment of OCF based on the stability of the O-C1-C2 joint complex reflected by the presence of displacement of the condyle, computed tomographic or radiographic evidence of O-C1-C2 instability, and magnetic resonance evidence of ligamentous injury. OCFs are divided into the following types: Type 1 (stable), undisplaced fracture; Type 2A (stable), displaced fracture with no ligamentous instability; and Type 2B (unstable), displaced fracture with ligamentous instability.
authors.affiliation: Division of Neurosurgery and Spinal Program, University of Toronto, Ontario, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Tuli
authors.forename: C H
authors.initials: CH
authors.lastname: Tator
authors.forename: M G
authors.initials: MG
authors.lastname: Fehlings
authors.forename: M
authors.initials: M
authors.lastname: Mackay
mesh_terms: D000368:Aged; D000716:Anatomy, Artistic; D005260:Female; D006801:Humans; D015994:Incidence; D008488:Medical Illustration; D008875:Middle Aged; D009777:Occipital Bone / Q000293:injuries*; D012189:Retrospective Studies; D012887:Skull Fractures / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*; D014057:Tomography, X-Ray Computed