Reoperation Risk Between Plated and Stand-Alone Anterior Cervical Discectomy and Fusion: A National Spine Registry-Based Cohort Study.

Abstract

Retrospective cohort study. Anterior cervical discectomy and fusions (ACDF) have become a common and effective means of decompression and stabilization of the cervical spine. Anterior instrumentation with plates and screws (ACDF-P) are increasingly utilized to increase rates of union. However, concerns with plate-related risks have led to the evolution of stand-alone ACDF (ACDF-S) constructs in hopes of reducing adjacent segment degeneration from plate prominence though critics have pointed out potential for subsidence, instability, and nonunions. We sought to evaluate reoperation risk following ACDF-S compared to ACDF-P in a multi-center US-based cohort. Adult patients who underwent primary 1-2-level ACDF between C3-C7 for degenerative disc disease were identified using a healthcare system's spine registry (2009-2022). 3,958 ACDF comprised the final study sample, 278 (7.0%) were ACDF-S. Procedures were performed by 59 surgeons at 16 hospitals. Multivariable Cox proportional-hazards regression was used to evaluate ACDF-S versus ACDF-P and risk of reoperation for any cause with confounder adjustment. Reoperation for adjacent segment disease (ASD) or nonunion were also evaluated. Secondary analysis stratified by 1 and 2-level ACDF procedures. In adjusted analyses, no differences in all-cause reoperation risk (hazard ratio [HR]=0.97, 95% confidence interval [CI]=0.58-1.64) or reoperation for ASD (HR=1.11, 95% CI=0.61-1.99) was observed when comparing ACDF-S to ACDF-P. No differences in reoperation risks were also found when restricted to 1-level procedures (all-cause: HR=0.92, 95% CI=0.50-1.68; ASD: HR=0.88, 95% CI=0.44-1.78). For 2-level procedures, there were 49 ACDF-S and 1,886 ACDF-P. There were too few events observed for regression analysis. In this large, comparative study including a cohort of nearly 4,000 patients, differences in reoperation rates for ACDF-S compared to ACDF-P constructs were not observed. This information could be used to better inform surgeons, patients, administrators, and policy makers between the two ACDF options.