title: Minimum four-year subsequent surgery rates of cervical disc replacement versus fusion: A meta-analysis of prospective randomized clinical trials.
abstract: Anterior cervical discectomy and fusion (ACDF) is a well-accepted surgical management strategy for radiculopathy and/or myelopathy. However, complications sometimes required subsequent surgery at the operated and adjacent levels. Artificial cervical disc replacement (ACDR) has been accepted as the most extensive non-fusion procedure and is designed to preserve motion. However, some specific complications can result in subsequent surgery, thus, attracting the attention of investigators.
  
  
  
  Compared with ACDF, ACDR had a lower subsequent surgery rates at both operated and adjacent levels after a minimum of four-years of follow-up.
  
  
  
  A meta-analysis was performed with articles published prior to February 2016. Only randomized controlled trials that reported a minimum of 4 years of follow-up with regard to the rates of subsequent surgeries after ACDR compared with ACDF were included in this study. Two reviewers independently screened the articles and data following the PRISMA statement.
  
  
  
  Our data showed that the pooled overall rate of subsequent surgery at the operated level and adjacent levels was lower in the ACDR group (7.4%) than in the ACDF group (16.8%) (P=0.0006). For subsequent surgery at the operated level, patients who received ACDR had a lower rate of subsequent surgery than patients who received ACDF (P<0.0001). With respect to the adjacent level, ACDR also had fewer subsequent surgeries compared with ACDF (P<0.0001).
  
  
  
  ACDR had significantly fewer subsequent surgical interventions compared with ACDF, However, a review of the literature showed that there were an insufficient number of studies with respect to subsequent surgery with a minimum of 4 years of follow-up. Hence, longer-term, multicenter studies are needed for better evaluation of the rate of subsequent surgery after ACDR.
  
  
  
  Level I, meta-analysis of high-powered prospective randomized trials.
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guo Xue Rd, Sichuan 610041, China.
authors.forename: T K
authors.initials: TK
authors.lastname: Wu
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guo Xue Rd, Sichuan 610041, China. Electronic address: dr.liuhao6304@hotmail.com.
authors.forename: H
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guo Xue Rd, Sichuan 610041, China.
authors.forename: B Y
authors.initials: BY
authors.lastname: Wang
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guo Xue Rd, Sichuan 610041, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Meng
mesh_terms: D002574:Cervical Vertebrae / Q000601:surgery; D017586:Diskectomy / Q000009:adverse effects; D006801:Humans; D007403:Intervertebral Disc / Q000601:surgery; D016032:Randomized Controlled Trials as Topic; D012086:Reoperation / Q000706:statistics & numerical data*; D013123:Spinal Fusion / Q000009:adverse effects / Q000706:statistics & numerical data*; D059145:Total Disc Replacement / Q000009:adverse effects / Q000706:statistics & numerical data*; D016896:Treatment Outcome
keywords: Cervical disc replacement; Fusion; Subsequent surgery