Utility of helical computed tomography in differentiating unilateral and bilateral facet dislocations.

Journal Article (Journal Article)

OBJECTIVE: Diagnosis of cervical facet dislocation is difficult when relying on plain radiographs alone. This study evaluates the interobserver reliability of helical computed tomography (CT) in the assessment of cervical translational injuries, correlates the radiographic diagnosis with intraoperative observation, and examines the role of neurologic injury in the evaluation and diagnosis of these injuries. METHODS: Clinical histories and radiographic studies of 10 patients with cervical facet dislocations were presented to 25 surgeons. Participants classified cases as unilateral or bilateral facet dislocations after reviewing selected axial CT slices and sagittal reconstructions. Surgeons' interpretations were compared with intraoperative diagnosis. Participants interpreted the same radiographic studies with 3 different clinical scenarios: neurologically intact, incomplete, and complete spinal cord injury. Vertebral body translation from midsagittal CT was evaluated to confirm whether all unilateral facet dislocations had <25% translation. RESULTS: Interrater kappa coefficient showed moderate agreement between observers in classifying injuries as unilateral or bilateral (kappa: 0.54-0.58), regardless of neurologic status. Percent agreement among observers varied from 50% to 100% for each individual case. Agreement was statistically higher for bilateral facet dislocation (85%) than for unilateral dislocations (78%), with 1 unilateral fracture showing nearly 50% translation on a midsagittal image. CONCLUSIONS: The addition of helical CT to reconstruction enables spine surgeons to more reliably distinguish bilateral from unilateral cervical facet dislocations. Despite frequent occurrence of these injuries and presumed agreement on injury description, agreement may be improved by a more precise definition of facet dislocations and subluxations and thorough review of all imaging studies.

Full Text

Duke Authors

Cited Authors

  • Dailey, AT; Shaffrey, CI; Rampersaud, R; Lee, J; Brodke, DS; Arnold, P; Nassr, A; Harrop, JS; Grauer, J; Bono, CM; Dvorak, M; Vaccaro, A

Published Date

  • 2009

Published In

Volume / Issue

  • 32 / 1

Start / End Page

  • 43 - 48

PubMed ID

  • 19264048

Pubmed Central ID

  • PMC2647499

International Standard Serial Number (ISSN)

  • 1079-0268

Digital Object Identifier (DOI)

  • 10.1080/10790268.2009.11760751


  • eng

Conference Location

  • England