Although CON status was associated with lower per capita utilization of TKA, the annual incidence of TKA appears to have increased over time more rapidly in states with CON laws compared with non-CON states (overall increase of 5.6% vs 2.3%, P < .01). When normalized to the Medicare population, the incidence of TKA increased 2.0% in CON states, whereas it actually decreased 7.2% in states without CON regulations (P = .011). Average reimbursement (and thus Medicare spend) was 5% to 10% lower in non-CON states at all time points (P < .0001). In non-CON states, relatively more TKAs appear to be performed in lower volume hospitals. Examination of adverse events rates did not reveal any strong associations between any adverse outcome and CON status.