Study design: Prospective randomized clinical trial.
Objective: Determine the reasons for, and rates of, secondary surgical intervention up to 5 years at both the index and adjacent levels in patients treated with cervical total disc replacement (TDR) or anterior cervical discectomy and fusion (ACDF). Patients undergoing TDR received ProDisc-C.
Summary of background data: Several outcome-based prospective, randomized clinical trials have shown cervical TDR to be equivalent, if not superior, to fusion. The ability of TDR to allow decompression while maintaining motion has led many to suggest that adjacent-level degeneration and reoperation rates may be decreased when compared with fusion.
Methods: A total of 209 patients were treated and randomized (TDR, n = 103; ACDF, n = 106) at 13 sites. A secondary surgical intervention at any level was considered a reoperation.
Results: At 5 years, patients who received ProDisc-C had statistically significant higher probability of no secondary surgery at the index and adjacent levels than patients who underwent ACDF (97.1% vs. 85.5%, P = 0.0079). No reoperations in patients who received ProDisc-C were performed for implant breakages or device failures. For patients who underwent ACDF, the most common reason for reoperation at the index level was pseudarthrosis, and for patients who underwent both ACDF and TDR, the most common reason for adjacent-level surgery was recurrent neck and/or arm pain.
Conclusion: Five-year follow-up of a prospective randomized clinical trial revealed 5-fold difference in reoperation rates when comparing patients who underwent ACDF (14.5%) with patients who underwent TDR (2.9%). These findings suggest the durability of TDR and its potential to slow the rate of adjacent-level disease.