title: Prospective, Randomized Comparison of One-level Mobi-C Cervical Total Disc Replacement vs. Anterior Cervical Discectomy and Fusion: Results at 5-year Follow-up.
abstract: BACKGROUND
  There is increasing interest in the role of cervical total disc replacement (TDR) as an alternative to anterior cervical discectomy and fusion (ACDF). Multiple prospective randomized studies with minimum 2 year follow-up have shown TDR to be at least as safe and effective as ACDF in treating symptomatic degenerative disc disease at a single level. The purpose of this study was to compare outcomes of cervical TDR using the Mobi-C(®) with ACDF at 5-year follow-up.
  
  
  METHODS
  This prospective, randomized, controlled trial was conducted as a Food and Drug Administration regulated Investigational Device Exemption trial across 23 centers with 245 patients randomized (2:1) to receive TDR with Mobi-C(®) Cervical Disc Prosthesis or ACDF with anterior plate and allograft. Outcome assessments included a composite overall success score, Neck Disability Index (NDI), visual analog scales (VAS) assessing neck and arm pain, Short Form-12 (SF-12) health survey, patient satisfaction, major complications, subsequent surgery, segmental range of motion, and adjacent segment degeneration.
  
  
  RESULTS
  The 60-month follow-up rate was 85.5% for the TDR group and 78.9% for the ACDF group. The composite overall success was 61.9% with TDR vs. 52.2% with ACDF, demonstrating statistical non-inferiority. Improvements in NDI, VAS neck and arm pain, and SF-12 scores were similar between groups and were maintained from earlier follow-up through 60 months. There was no significant difference between TDR and ACDF in adverse events or major complications. Range of motion was maintained with TDR through 60 months. Device-related subsequent surgeries (TDR: 3.0%, ACDF: 11.1%, p<0.02) and adjacent segment degeneration at the superior level (TDR: 37.1%, ACDF: 54.7%, p<0.03) were significantly lower for TDR patients.
  
  
  CONCLUSIONS
  Five-year results demonstrate the safety and efficacy of TDR with the Mobi-C as a viable alternative to ACDF with the potential advantage of lower rates of reoperation and adjacent segment degeneration, in the treatment of one-level symptomatic cervical degenerative disc disease.
  
  
  CONCLUSIONS
  This prospective, randomized study with 5-year follow-up adds to the existing literature indicating that cervical TDR is a viable alternative to ACDF in appropriately selected patients.
  
  
  METHODS
  This is a Level I study.
authors.affiliation: Texas Back Institute, Denton, Texas.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Hisey
authors.affiliation: Texas Back Institute, Plano, Texas.
authors.forename: Jack E
authors.initials: JE
authors.lastname: Zigler
authors.affiliation: Saddleback Memorial Medical Center, Laguna Hills, California.
authors.forename: Robert
authors.initials: R
authors.lastname: Jackson
authors.affiliation: Spine Institute of Louisiana, Shreveport, Louisiana.
authors.forename: Pierce D
authors.initials: PD
authors.lastname: Nunley
authors.affiliation: Cedars Sinai Spine Center, Los Angeles, California.
authors.forename: Hyun W
authors.initials: HW
authors.lastname: Bae
authors.affiliation: Department of Neurological Surgery, University of California, Davis, Sacramento, California.
authors.forename: Kee D
authors.initials: KD
authors.lastname: Kim
authors.affiliation: Texas Back Institute Research Foundation, Plano, Texas.
authors.forename: Donna D
authors.initials: DD
authors.lastname: Ohnmeiss
keywords: Cervical Spine; Mobi-C® Cervical Disc Prosthesis; anterior cervical fusion; artificial disc; cervical arthroplasty; clinical outcome; degenerative disc disease; randomized trial; total disc replacement