title: Superiority of multilevel cervical arthroplasty outcomes versus single-level outcomes: 229 consecutive PCM prostheses.
abstract: METHODS
  Class 2 level of evidence: This is a prospective, consecutive series of 229 prosthetic implantations that were concurrently enrolled between single-level versus multilevel cervical arthroplasty comprising an FDA Pilot Study.
  
  
  OBJECTIVE
  This study investigated multilevel cervical disc replacement in relation to single-level cervical arthroplasty to find if the same reduction in clinical success would occur with this alternative treatment.
  
  
  BACKGROUND
  Usually, the clinical outcomes of instrumented cervical fusions deteriorate as the number of vertebral levels of involvement increases.
  
  
  METHODS
  A total of 229 patients presented with cervical herniated nucleus pulposus, cervical spondylosis, and/or adjacent segment disease with cervical radiculopathy or myelopathy. Following anterior cervical neurologic decompression seventy-one patients required porous coated motion (PCM) cervical arthroplasties from C3-C4 to C7-T1 (Group S, single level). Sixty-nine patients underwent 158 multilevel PCM cervical arthroplasties (Group M, multilevel) during the same time interval, for the same indications, performed by the same surgeons under the same clinical protocol: double level, 53 cases; three levels, 12 cases: and 4 levels, 4 cases.
  
  
  RESULTS
  The self-assessment outcomes instruments showed significantly more improvement for the multilevel cases. The mean improvement in the NDI for the single cases was 37.6% versus the multilevel cases mean improvement in NDI was 52.6% (P = 0.021). The difference between the two was statistically significant. The mean improvement in the VAS showed the same association: single-level mean improvement 58.4% versus the multilevel cases mean VAS improvement was 65.9%. The Odom's were also more improved for the multilevel versus the single-level group: 93.9% versus 90.5% in the excellent, good, and fair categories. The reoperation rates and serious adverse events were similar between the single-level (S = 3) to the multilevel arthroplasty (M = 2) groups. Kaplan-Meier implant survivorship analysis at 3 years for the cohort of 229 prostheses was 94.5% (confidence interval, 1.00-0.820).
  
  
  CONCLUSIONS
  This prospective study of cervical arthroplasty is the first report to date showing significantly improved clinical outcomes for multilevel cervical arthroplasty compared with single-level cervical disc replacement using an FDA validated outcome instrument.
authors.affiliation: St. Joseph Hospital Scoliosis and Spine Center, Baltimore, MD, USA. MACK8132@gmail.com
authors.forename: Luiz
authors.initials: L
authors.lastname: Pimenta
authors.forename: Paul C
authors.initials: PC
authors.lastname: McAfee
authors.forename: Andy
authors.initials: A
authors.lastname: Cappuccino
authors.forename: Bryan W
authors.initials: BW
authors.lastname: Cunningham
authors.forename: Roberto
authors.initials: R
authors.lastname: Diaz
authors.forename: Etevaldo
authors.initials: E
authors.lastname: Coutinho
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D018572:Disease-Free Survival; D017586:Diskectomy / Q000379:methods*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011446:Prospective Studies; D019736:Prostheses and Implants; D011843:Radiculopathy / Q000000981:diagnostic imaging / Q000601:surgery; D011859:Radiography; D013118:Spinal Cord Diseases / Q000000981:diagnostic imaging / Q000601:surgery; D013123:Spinal Fusion / Q000379:methods*; D013128:Spinal Osteophytosis / Q000000981:diagnostic imaging / Q000601:surgery; D016896:Treatment Outcome