Geospatial Evaluation of Disparities in Access to Cervical Spine Fusion in Metropolitan Areas Across the United States

Abstract

Study Design: Retrospective study with epidemiologic analysis of public Medicare data. Objective: The purpose of this study is to use geospatial analysis to identify disparities in access to cervical spine fusions in metropolitan Medicare populations. Summary of Background Data: Cervical spine fusion is among the most common elective procedures performed by spine surgeons and is the most common surgical intervention for degenerative cervical spine disease. Although some studies have examined demographic and socioeconomic trends in cervical spine fusion, few have attempted to identify where disparities exist and quantify them at a community level. Methods: Center for Medicare and Medicaid Services physician billing and Medicare demographic data sets from 2013 to 2020 were filtered to contain only cervical spine fusion procedures and then combined with US Census socioeconomic data. The Moran Index geospatial clustering algorithm was used to identify statistically significant hotspot and coldspots of cervical spine fusions per 100,000 Medicare members at a county level. Univariate and multivariate analysis was subsequently conducted to identify demographic and socioeconomic factors that are associated with access to care. Results: A total of 285,405 cervical spine fusions were analyzed. Hotspots of cervical spine fusion were located in the South, while coldspots were throughout the Northern Midwest, the Northeast, South Florida, and West Coast. The percent of Medicare patients that were Black was the largest negative predictor of cervical spine fusions per 100,000 Medicare members (β=−0.13, 95% CI: −0.16, −0.10). Conclusions: Barriers to access can have significant impacts on health outcomes, and these impacts can be disproportionately felt by marginalized groups. Accounting for socioeconomic disadvantage and geography, this analysis found the Black race to be a significant negative predictor of access to cervical spine fusions. Future studies are needed to further explore potential socioeconomic barriers that exist in access to specialized surgical care. Level of Evidence: Level III—retrospective.