title: Cervical Disc Arthroplasty with Prestige LP Disc Versus Anterior Cervical Discectomy and Fusion: Seven-Year Outcomes.
abstract: BACKGROUND
  Cervical disc arthroplasty (CDA) has emerged as an alternative to anterior cervical discectomy and fusion (ACDF) for the treatment of cervical pathologies. Studies are on-going to assess the long term outcomes of CDA. This study assessed the safety and efficacy of the Prestige(®) LP Disc at 84-months follow up.
  
  
  METHODS
  Prospective data from 280 CDA patients with single-level cervical disc disease with radiculopathy or myelopathy were compared with 265 historical control ACDF patients. Clinical and radiographic follow up was completed pre-operatively, intraoperatively, and at intervals up to 84 months.
  
  
  RESULTS
  Follow-up rate was 75.9% for CDA and 70.0% for ACDF patients. Statistical improvements (p < 0.001) in Neck Disability Index (NDI), neck/arm pain, and SF-36 were achieved by 1.5 months in both groups and maintained through 84 months. At 84 months, 86.1% of CDA versus 80.1% of ACDF patients achieved NDI success, (≥15-point improvement over baseline). Mean NDI score improvements exceeded 30 points in both groups. SF-36 PCS/MCS mean improvements were 13.1±11.9/8.2±12.3 points for CDA and 10.7±11.8/8.3±13.6 points for ACDF. Neurological success was 92.8% for CDA and 79.7% for ACDF patients. The rate of Overall Success was 74.9% for CDA and 63.2% for ACDF. At 84 months, 17.5% of CDA and 16.6% of ACDF patients had a possibly implant- or implant-surgical procedure-related adverse event. Eighteen (6.4%) CDA and 29 (10.9%) ACDF patients had a second surgery at the index level. In CDA patients, mean angular motion at the target level was maintained at 24 (7.5°) and 84 (6.9°) months. Bridging bone was reported in 5.9%/9.5%/10.2%/13.0% of CDA patients at 24/36/60/84 months. Change in mean preoperative angulation of the adjacent segment above/below the index level was1.06±4.39/1.25±4.06 for CDA and (-0.23)±5.37/1.25±5.07 for ACDF patients. At 84 months, 90.9% of CDA and 85.6% of ACDF patients were satisfied with the results of their treatment.
  
  
  CONCLUSIONS
  Prestige LP maintained significantly improved clinical outcomes and segmental motion; statistical superiority of CDA was concluded for overall success. This investigational device exemption study was sponsored by Medtronic Spinal and Biologics, Memphis, TN. Study approved by the Hughston Sports Medicine Center Institutional Review Board on January 7, 2005. Clinical trial registered at clinicaltrials.gov: NCT00667459. All participants signed an informed consent.
authors.affiliation: The Orthopedic Center of St. Louis, St. Louis, Missouri.
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Gornet
authors.affiliation: Wilderness Spine Services, The Hughston Clinic, Columbus, Georgia.
authors.forename: J Kenneth
authors.initials: JK
authors.lastname: Burkus
authors.affiliation: Department of Neurosurgery, University of Virginia, Charlottesville, Virginia.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Shaffrey
authors.affiliation: Vanderbilt University School of Medicine, Department of Biostatistics, Nashville, Tennessee.
authors.forename: Hui
authors.initials: H
authors.lastname: Nian
authors.affiliation: Vanderbilt University School of Medicine, Department of Biostatistics, Nashville, Tennessee.
authors.forename: Frank E
authors.initials: FE
authors.lastname: Harrell
keywords: adjacent level disease; anterior cervical discectomy and fusion; artificial cervical disc; cervical disc arthroplasty; cervical myelopathy; cervical radiculopathy