title: Pseudoarthrosis rates in anterior cervical discectomy and fusion: a meta-analysis.
abstract: BACKGROUND
  Anterior cervical discectomy and fusion (ACDF) is a commonly performed procedure for patients presenting with cervical radiculopathy, myelopathy, or deformity. A systematic literature review and meta-analysis of pseudoarthrosis rates associated with ACDF with plate fixation have not been previously performed.
  
  
  OBJECTIVE
  The purpose of this study was to identify all prospective studies reporting pseudoarthrosis rates for ACDF with plate fixation.
  
  
  METHODS
  This study is based on a systematic review and meta-analysis.
  
  
  METHODS
  Studies reporting pseudoarthrosis rates in patients who received one-, two-, or three-level ACDF surgeries were included.
  
  
  METHODS
  Outcomes of interest included reported pseudoarthrosis events after ACDF with plate fixation.
  
  
  METHODS
  We conducted a MEDLINE, SCOPUS, Web of Science, and EMBASE search for studies reporting complications for ACDF with plate fixation. We recorded pseudoarthrosis events from all included studies. A meta-analysis was performed to calculate effect summary mean values, 95% confidence intervals (CIs), Q statistics, and I(2) values. Forest plots were constructed for each analysis group.
  
  
  RESULTS
  Of the 7,130 retrieved articles, 17 met the inclusion criteria. The overall pseudoarthrosis rate was 2.6% (95% CI: 1.3-3.9). Use of autograft fusion (0.9%, 95% CI: -0.4 to 2.1) resulted in a reduced pseudoarthrosis rate compared with allograft fusion procedures (4.8%, 95% CI: 1.7-7.9). Studies were separated based on the length of follow-up: 12 to 24 and greater than 24 months. These groups reported rates of 3.1% (95% CI: 1.2-5.0) and 2.3% (95% CI: 0.1-4.4), respectively. Studies performing single-level ACDF yielded a rate of 3.7% (95% CI: 1.6-5.7). Additionally, there was a large difference in the rate of pseudoarthrosis in randomized controlled trials (4.8%, 95% CI: 2.6-7.0) versus prospective cohort studies (0.2%, 95% CI: -0.1 to 0.5), indicating that the extent of follow-up criteria affects the rate of pseudoarthrosis.
  
  
  CONCLUSIONS
  This review represents a comprehensive estimation of the actual incidence of pseudoarthrosis across a heterogeneous group of surgeons, patients, and ACDF techniques. The definition of pseudoarthrosis varied significantly within the literature. To ensure its diagnosis and prevent sequelae, standardized criteria need to be established. This investigation sets the framework for surgeons to understand the impact of surgical techniques on the rate of pseudoarthrosis.
authors.affiliation: Case Western Reserve University School of Medicine, 2109 Adelbert Rd, Cleveland, OH 44106, USA. Electronic address: mfs82@case.edu.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Shriver
authors.affiliation: Baylor College of Medicine, 1 Baylor Plaza, Houston, TX 77030, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Lewis
authors.affiliation: Department of Neurosurgery, Neurological Institute, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA; Center for Spine Health, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA.
authors.forename: Varun R
authors.initials: VR
authors.lastname: Kshettry
authors.affiliation: Department of Neurosurgery, Neurological Institute, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA; Center for Spine Health, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA.
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Rosenbaum
authors.affiliation: Department of Neurosurgery, Neurological Institute, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA; Center for Spine Health, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA.
authors.forename: Edward C
authors.initials: EC
authors.lastname: Benzel
authors.affiliation: Center for Spine Health, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA; Department of Orthopaedic Surgery, Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195, USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Mroz
mesh_terms: D001860:Bone Plates / Q000009:adverse effects; D017586:Diskectomy / Q000009:adverse effects*; D006801:Humans; D011542:Pseudarthrosis / Q000209:etiology*; D011843:Radiculopathy / Q000601:surgery*; D013118:Spinal Cord Diseases / Q000601:surgery*; D013123:Spinal Fusion / Q000009:adverse effects*
keywords: ACDF; Anterior cervical discectomy and fusion; Complication; Meta-analysis; Nonunion; Pseudoarthrosis