Anterior cervical decompression and fusion at one and two levels: trends and factors associated with structural allograft versus synthetic cages

Abstract

BackgroundFollowing decompression in anterior cervical discectomy and fusion (ACDF), reconstruction is typically done with structural allograft or a synthetic cage. Relative trends and factors associated with utilizing these implants have not been well characterized. MethodsThe PearlDiver 2011 to 2021 M157 database was used to identify adult patients undergoing 1- or 2-level ACDF. The incidence of structural allograft versus synthetic cage utilized was compared by year. Patient factors predictive of synthetic cage use as the structural interbody for ACDF were assessed with multivariable analysis. Further, the use of anterior plates was trended to provide a measure of usage of stand-alone devices (this comparison was made beginning with 2016 based on coding limitations). ResultsOf 173,833 isolated 1- or 2-level ACDF cases identified, structural allograft was used for 63,029 (36.3%) and synthetic cages were used for 110,804 (63.8%). The use of synthetic cages increased from 51.1% of cases in 2011 to 75.8% of cases in 2021 (p < 0.0001). Independent clinical predictors of synthetic cage use were: older age (odds ratio [OR] 1.02 per decade), female sex (OR 1.04), and greater ECI (OR 1.09 per 2-point increase).Independent non-clinical predictors of synthetic cage use were: geographic region (Northeast OR 1.11, South OR 1.85, and West 2.08, each relative to Midwest), and provider specialty (orthopedic OR 1.06 relative to neurosurgeons). There was an increase in the percent of synthetic cases without separately coded plate (“stand-alone” interbody cages: 21.7% in 2016 to 35.3% in 2021, p < 0.001). ConclusionsThe usage of synthetic cages in 1- and 2- level ACDF has increased relative to structural allograft between 2011 and 2021 in the United States and more recently the use of “stand-alone” synthetic cages has been on the rise. Non-clinical as well as clinical factors were associated with implant choice, suggesting room for more consistent care algorithms.