A Regional Analysis of Hospital Readmissions Following Total Hip and Knee Arthroplasty and the Impact of Medicaid Expansion

The Hospital Readmissions Reduction Program (HRRP) works to temper nationally rising readmission rates. Total knee arthroplasty (TKA) and total hip arthroplasty (THA) have a 30-day readmission cost burden of $889,300 and $689,400, respectively. No research has compared TKA and THA readmission rates by region and Medicaid expansion status. This study compares THA and TKA readmission rates in the United States by region, Medicaid status, and performance. One-way ANOVAs were conducted to determine the regions with the highest and lowest mean excess readmission ratios (ERRs). An independent t-test compared Medicaid versus non-Medicaid expansion states. Southern hospitals have the highest mean ERR, followed by northeastern, midwestern, and then western hospitals. Although Medicaid expansion states have significantly lower ERRs compared to non-expansion states, Medicaid status alone does not account for regional differences in ERRs after THA and TKA. Regional factors likely confound Medicaid status’s effect on readmission rates. (Journal of Surgical Orthopaedic Advances 32(1):005–008, 2023)

Key Words: readmission, total hip arthroplasty, total knee arthroplasty, Medicaid