Iorio R, et al. - Researchers studied at 3 levels of the inpatient-only (IPO) rule influence on total knee arthroplasty (TKA) for Medicare beneficiaries: a national comparison of FFS inpatient and outpatient classification for 2017 vs 2018; a survey of AAHKS surgeons completed in April 2019; and an in-depth analysis of a large academic medical center experience. Researchers examined an analysis of change in admission classification of individuals with TKA over time, a number of QIO audits, compliance solutions for the new rule, and cost implications of those compliance solutions. This survey displayed that 66 of 374 (17.65%) individuals had experienced a QIO audit as a result of issues with the IPO rule. In addition, there are many unintended outcomes to the IPO rule application to TKA.