title: Comparative effectiveness of surgical versus nonoperative management of unilateral, nondisplaced, subaxial cervical spine facet fractures without evidence of spinal cord injury: clinical article.
abstract: OBJECTIVE
  Facet joints are major stabilizers of cervical motion allowing for effortless and pain-free multidimensional cervical spine movements without significant linear or rotational translation, thus minimizing any chance for spinal cord or nerve root impingement. Unilateral, nondisplaced subaxial facet fractures do not meet the conventional criteria for spinal instability under physiological loads. Limited evidence indicates that even with no or minimal displacement, 20%-80% of these fractures fail nonoperative management. The risk factors for instability in isolated nondisplaced subaxial facet fractures remain uncertain. In this retrospective study of prospectively collected data, the authors attempted to identify the predictors of failure in the management of isolated, nondisplaced subaxial facet fractures admitted to their Level I trauma center over a 10-year period.
  
  
  METHODS
  Demographic, clinical, imaging, and follow-up data for 25 patients with unilateral nondisplaced subaxial facet fractures who were managed surgically (n = 10) or nonoperatively (n = 15) were statistically analyzed.
  
  
  RESULTS
  The mean age of the patients was 38 years, 19 were male, and 21 of the fractures were the result of either motor vehicle accidents or falls. The mean motor score on the American Spinal Injury Association scale was 99.2, and the mean Subaxial Injury Classification (SLIC) severity score was 3 (operated 3.5, nonoperated 2.3). Allen mechanistic classification included 22 compressive-extension Stage 1 and 2 distractive-extension Stage 1 fractures. Subaxial facet fractures involved C-7 in 17 patients (68%), C-6 in 7 (28%), and C-3 in 1 (4%). The anatomical plane of fracture through the lateral mass was sagittal in 12 patients, axial in 8, and coronal in 3 patients. Nondisplaced floating lateral mass injuries were noted in 2 patients. The mean instability score, considering 7 components of the discoligamentous complex on MRI, was 3.2 (operated 3.6, nonoperated 3.0). Ten (40%) of 25 patients in this investigation did not have successful management, 9 in the nonoperated and 1 in the operated group (p = 0.018). Unsuccessful management was significantly greater in younger patients (p = 0.0008), possibly indicating selection bias (p = 0.07, Wilcoxon ranksum test). Fracture plane, instability, and SLIC scores did not play a significant role in treatment failure in this study.
  
  
  CONCLUSIONS
  In this study, surgery was superior to nonoperative management of isolated, nondisplaced, or minimally displaced subaxial cervical spine facet fractures.
authors.affiliation: Departments of Neurosurgery and.
authors.forename: Bizhan
authors.initials: B
authors.lastname: Aarabi
authors.forename: Stuart
authors.initials: S
authors.lastname: Mirvis
authors.forename: Kathirkamanthan
authors.initials: K
authors.lastname: Shanmuganathan
authors.forename: Alexander R
authors.initials: AR
authors.lastname: Vaccaro
authors.forename: Cassandra J
authors.initials: CJ
authors.lastname: Holmes
authors.forename: Noori
authors.initials: N
authors.lastname: Akhtar-Danesh
authors.forename: Michael G
authors.initials: MG
authors.lastname: Fehlings
authors.forename: Marcel F
authors.initials: MF
authors.lastname: Dvorak
mesh_terms: D000293:Adolescent; D000328:Adult; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries / Q000601:surgery*; D057186:Comparative Effectiveness Research; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009989:Orthotic Devices; D012189:Retrospective Studies; D013119:Spinal Cord Injuries; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000601:surgery / Q000628:therapy*; D013123:Spinal Fusion / Q000379:methods*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult; D021801:Zygapophyseal Joint / Q000000981:diagnostic imaging / Q000293:injuries / Q000601:surgery*