Revision Rates After Single-Level Cervical Disc Arthroplasty Versus Anterior Cervical Discectomy and Fusion

Study Design. Retrospective Case-Control study. Objectives. This study aimed to compare rates and risk factors for all-cause 5-year revisions for patients undergoing primary single-level cervical disc arthroplasty (CDA) versus Anterior Cervical Discectomy and Fusion (ACDF). Summary of Background Data. Prospective studies have compared patient reported outcomes, adjacent segment degeneration, and long-term revisions between CDA and ACDF. Despite these high-level evidence studies, well-powered, large investigations have not been adequately reported. Patients and Methods. A nationwide database was queried for patients undergoing primary single level CDA or ACDF for degenerative cervical spine pathology. Further inclusion criteria consisted of patients having a minimum of 5-year follow-up. Patients undergoing CDA were 1:5 ratio matched to patients undergoing ACDF by age, sex, comorbidities, and overall Elixhauser comorbidity index (ECI). Objectives were to compare the rates and risk factors of all-cause 5-year revisions for those undergoing single level CDA versus ACDF. Multivariate logistic regression models computed odds ratios (OR) of revisions within 5 years. P values less than 0.001 were significant. Results. A total of 32,953 patients underwent single level CDA (N=5,640) or ACDF (N=27,313) with 5-Year minimum follow-up. The incidence of all cause revisions within 5 years were 1.24% for CDA and 9.23% for ACDF ( P <0.001). After adjustment, patients undergoing single level ACDF had significantly higher odds of all-cause revisions within 5 years (OR: 8.09; P <0.0001). Additional patient specific factors associated with revisions were a history of reported drug abuse (OR: 1.51; P <0.0001), depression (OR: 1.23; P <0.0001), cardiac arrythmias (OR: 1.21; P =0.0008), hypertension (OR: 1.20; P =0.0006), and tobacco use (OR: 1.18; P =0.0003). Conclusions. In this study of nearly 33,000 single level cervical spine surgeries with minimum 5-year follow-up, all-cause revision rates were significantly lower for patients undergoing CDA. Surgeons may use this data to counsel patients regarding 5-year revisions following single level CDA or ACDF. Level of Evidence. III.