Comparison of Clinical Outcomes of 1- and 2-Level Total Disc Replacement: Four-Year Results From a Prospective, Randomized, Controlled, Multicenter IDE Clinical Trial

Spine (Phila Pa 1976). 2015 Jun 1;40(11):759-66. doi: 10.1097/BRS.0000000000000887.

Abstract

Study design: A prospective, randomized, multicenter Food and Drug Administration Investigation Device Exemption study using total disc replacement as surgical treatment of degenerative disc disease at 1 or 2 contiguous levels of the cervical spine.

Objective: To evaluate the safety and effectiveness of total disc replacement at single or 2 contiguous levels through 48 months of follow-up.

Summary of background data: Cervical total disc replacement has been shown to be a safe and effective alternative to anterior cervical discectomy and fusion at 24 months. Its motion-preserving capabilities may avoid accelerating adjacent segment pathology and thereby lower the rate of associated complications.

Methods: Patients were randomized in a 2:1 ratio (total disc replacement [TDR]: anterior cervical discectomy and fusion [ACDF]) at 24 sites. Ultimately, 164 patients received TDR at 1 level and 225 patients received TDR at 2 contiguous levels. An additional 24 patients (15 one-level, 9 two-level) were treated with TDR as training cases.Outcome measures included neck disability index, visual analogue scale neck and arm pain, Short Form 12-item Health Survey (SF-12) Mental Composite Score (MCS) and Physical Composite Score (PCS), range of motion, major complication rates, and secondary surgery rates. Patients received follow-up examinations at regular intervals through 4 years after surgery.

Results: Preoperative characteristics were statistically similar for the 1- and 2-level patient groups. Four-year follow-up rates were 83.1% (1-level) and 89.0% (2-level). There was no statistically significant difference between 1- and 2-level TDR groups for all clinical outcome measures. Both TDR groups experienced significant improvement at each follow-up when compared with preoperative scores. One case of migration was reported in the 2-level TDR group.

Conclusion: A 4-year post hoc comparison of 1- and 2-level TDR patients concurrently enrolled in a 24-center, Food and Drug Administration Investigation Device Exemption clinical trial indicated no statistical differences between groups in clinical outcomes, overall complication rates, and subsequent surgery rates.

Level of evidence: 1.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Cervical Vertebrae* / diagnostic imaging
  • Disability Evaluation
  • Follow-Up Studies
  • Humans
  • Intervertebral Disc Degeneration / complications
  • Intervertebral Disc Degeneration / physiopathology
  • Intervertebral Disc Degeneration / surgery*
  • Neck Pain / etiology
  • Pain Measurement
  • Patient Satisfaction
  • Prospective Studies
  • Radiculopathy / complications
  • Radiography
  • Range of Motion, Articular
  • Reoperation
  • Single-Blind Method
  • Total Disc Replacement* / adverse effects
  • Total Disc Replacement* / instrumentation