title: Complete cervical intervertebral disc extrusion with spinal cord injury in the absence of facet dislocation: a case report.
abstract: METHODS
  Complete cervical disc complex extrusion, defined as the extrusion of both cartilaginous end-plates, the entire nucleus pulposus, and portions of the anulus fibrosus, is rare. A case of complete cervical disc complex extrusion with spinal cord injury in the absence of facet dislocation or subluxation in an obtunded patient is reported.
  
  
  OBJECTIVE
  To report an unusual presentation of spinal cord injury and the occurrence of complete traumatic cervical disc complex extrusion in the absence of facet dislocation and normal plain radiographic findings.
  
  
  BACKGROUND
  Traumatic cervical disc herniation occurs in 54% to 80% of patients with facet dislocation. A report of complete extrusion of a cervical intervertebral disc complex (cartilaginous endplate, anulus, and nucleus pulposus) with spinal cord injury in the absence of dislocation has not been described, to the best of the authors' knowledge.
  
  
  METHODS
  A clinical and radiographic review of such a case of complete traumatic cervical disc complex herniation in the absence of dislocation was performed.
  
  
  RESULTS
  Plain radiographic imaging did not show any injury. A nondisplaced fracture of the left inferior facet joint was evident on computed tomography. The diagnosis of C4-C5 intervertebral disc extrusion was made only after magnetic resonance imaging. The vacuum effect of complete disc extrusion created a "white-out" appearance to the disc space on the sagittal T2 magnetic resonance image. The patient underwent anterior cervical discectomy and fusion with additional posterior cervical fusion. He subsequently regained functional strength against gravity in two of four limbs. He remains completely paraparetic in the left upper extremity and partially paraparetic in the left lower extremity.
  
  
  CONCLUSIONS
  The case report highlights the occurrence of complete traumatic cervical disc extrusion in the absence of facet dislocation with normal plain radiographic findings and consequent spinal cord injury, which can accompany such an injury.
authors.affiliation: Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, New Haven, Connecticut, USA. james.yue@yale.edu
authors.forename: James J
authors.initials: JJ
authors.lastname: Yue
authors.forename: Brandon D
authors.initials: BD
authors.lastname: Lawrence
authors.forename: Karen M
authors.initials: KM
authors.lastname: Sutton
authors.forename: John J
authors.initials: JJ
authors.lastname: Strugar
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Haims
mesh_terms: D000063:Accidents, Traffic; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries* / Q000601:surgery; D017586:Diskectomy; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019838:Neck Injuries / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D020127:Recovery of Function; D013119:Spinal Cord Injuries / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D016103:Spinal Fractures / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D013123:Spinal Fusion; D014057:Tomography, X-Ray Computed