title: Is external cervical orthotic bracing necessary after posterior atlantoaxial fusion with modern instrumentation: meta-analysis and review of literature.
abstract: BACKGROUND
  No guidelines exist regarding external cervical orthoses (ECO) after atlantoaxial fusion. We reviewed published series describing C1-2 posterior instrumented fusions with screw-rod constructs (SRC) or transarticular screws (TAS) and compared rates of fusion with and without postoperative ECO.
  
  
  METHODS
  Online databases were searched for English-language articles between 1986 and April 2011 describing ECO use after posterior atlantoaxial instrumentation with SRC or TAS. Eighteen studies describing 947 patients who had SRC (± ECO: 254 of 693 patients), and 33 studies describing 1424 patients with TAS (± ECO: 525 of 899 patients) met inclusion criteria. Meta-analysis techniques were applied to estimate rates of fusion with and without ECO use.
  
  
  RESULTS
  All studies provided class III evidence, and no studies directly compared outcomes with or without ECO use. There was no significant difference in the proportion of patients who achieved successful fusion between patients treated with ECO and without ECO for SRC or TAS patients. Point estimates and 95% confidence intervals (CI) for rates of fusion ± ECO were 97.4% (CI: 95.2% to 98.6%) versus 97.9% (CI: 93.6% to 99.3%) for SRC and 93.6% (CI: 90.7% to 95.6%) versus 95.3% (CI: 90.8% to 97.7%) for TAS. There was no correlation between duration of ECO treatment and fusion (dose effect).
  
  
  CONCLUSIONS
  After C1-2 fusion with modern instrumentation, ECO may be unnecessary (class III). Some centers recommend ECO use with patients with softer bone quality (class IV). Prospective, randomized studies with validated radiographic and clinical outcome metrics are necessary to determine the utility of ECO after C1-2 fusion and its impact on patient comfort and cost.
authors.affiliation: Neurosurgical Care, LLC, Royersford, Pennsylvania, USA. robertelliottmd@gmail.com
authors.forename: Robert E
authors.initials: RE
authors.lastname: Elliott
authors.forename: Omar
authors.initials: O
authors.lastname: Tanweer
authors.forename: Akwasi
authors.initials: A
authors.lastname: Boah
authors.forename: Amr
authors.initials: A
authors.lastname: Morsi
authors.forename: Tracy
authors.initials: T
authors.lastname: Ma
authors.forename: Anthony
authors.initials: A
authors.lastname: Frempong-Boadu
authors.forename: Michael L
authors.initials: ML
authors.lastname: Smith
mesh_terms: D001268:Atlanto-Axial Joint / Q000601:surgery*; D001915:Braces; D006801:Humans; D013123:Spinal Fusion / Q000295:instrumentation* / Q000534:rehabilitation