Long-Term Outcomes of Cervical Disc Replacement and Anterior Cervical Discectomy and Fusion: A Review of FDA IDE Trials With Real-World Comparison

Study designRetrospective comparative cohort study.ObjectiveTo validate FDA IDE-sponsored trial findings on cervical disc replacement (CDR) and anterior cervical discectomy and fusion (ACDF) by comparing reoperation outcomes with real-world data.MethodsPatients undergoing one- or two-level ACDF or CDR from 2010-2022 were identified in the PearlDiver (PD) database. FDA IDE trials were retrieved through review of databases. Subsequent surgeries and sample sizes were extracted at 2-, 4-, 5-, 7-, and 10-year intervals. Event rates were calculated as reoperations divided by patients at risk, and survival probabilities as S(t) = 1-event rate. Kaplan-Meier-style survival curves were reconstructed using the Guyot algorithm with a monotonicity constraint. Pooled FDA survival probabilities were weighted by number at risk. Hazard ratios (HRs) were derived from log-transformed survival probabilities, and statistical significance was tested using Pearson's chi-square or Fisher's exact test. Analyses were stratified by surgical level (1- vs 2-level) and procedure type (CDR vs ACDF).ResultsIn total, 277 146 ACDF and 25 957 CDR patients from PD and 46 FDA trials were analyzed. CDR reoperation risks were similar between FDA and PD cohorts, though differences were significant at 2-, 7-, and 10-year follow-up for 1-level procedures. ACDF reoperation risks were consistently and significantly lower in PD (eg, HR 0.4 at 7 years).ConclusionReoperation risks for CDR were broadly comparable, while ACDF outcomes were superior in practice compared with trials. These differences may reflect trial selection bias or stricter adjudication of ACDF outcomes. Validation against real-world data supports long-term safety assessment and personalized surgical decision-making.