The Effect of Pre-Affordable Care Act (ACA) Medicaid Eligibility Expansion in New York State on Access to Specialty Surgical Care

Background: Critics argue that expanding health insurance coverage through Medicaid may not result in improved access to care. The Affordable Care Act provides reimbursement incentives aimed at improving access to primary care services for new Medicaid beneficiaries; however, there are no such incentives for specialty services. Using the natural experiment of Medicaid expansion in New York (NY) State in October 2001, we examined whether Medicaid expansion increased access to common musculoskeletal procedures for Medicaid beneficiaries. Methods: From the State Inpatient Database for NY State, we identified 19- to 64-year-old patients who underwent lower extremity large joint replacement, spine procedures, and upper/lower extremity fracture/dislocation repair from January 1998 to December 2006. We used interrupted time series analysis to evaluate the association between Medicaid expansion and trends in the relative and absolute number of Medicaid beneficiaries who underwent these musculoskeletal procedures. Results: Before Medicaid expansion, we observed a slight but steady temporal decline in the proportion of musculoskeletal surgical patients who were Medicaid beneficiaries. After expansion, this trend reversed, and by 5 years after Medicaid expansion, the proportion of musculoskeletal surgical patients who were Medicaid beneficiaries was 4.7 percentage points [95% confidence interval, 3.9-5.5] higher than expected, based on the preexpansion time trend. Conclusion: Medicaid expansion in NY State significantly improved access to common musculoskeletal procedures for Medicaid beneficiaries.