AN ANALYSIS OF BUNDLED CARE FUNDING FOR TOTAL HIP AND KNEE ARTHROPLASTY IN ONTARIO: A POPULATION-BASED RETROSPECTIVE COHORT STUDY

Rising healthcare expenditures and dissatisfaction with traditional models of reimbursement have driven an interest in alternative payment model (APM) initiatives. Bundled funding, a variation of an APM, was implemented for elective total hip and knee arthroplasty (THA/TKA) in Ontario in 2019. This study aims to explore whether cost, procedure volume and quality of care were impacted by the program's introduction. Pre and post implementation patient cohorts were developed with aggregate data collected from the Canadian Institute for Healthcare Information and Canadian Joint Replacement Registry. Inclusion criteria consisted of an inpatient THA or TKA performed for a diagnosis of osteoarthritis in Ontario between April 2017 and February 2020. Quality was assessed via patient length of stay, revisions, readmissions and emergency department presentations. Cost was calculated by multiplying the average Resource Intensity Weight (RIW) for THA and TKA procedures by the provincial Cost of a Standard Hospital Stay (CSHS). Statistical analysis was performed comparing patient cohorts via χ² and t-tests. There were 32,683 THA/TKAs and 39,279 THA/TKAs performed in the pre-intervention and post-intervention cohorts respectively. Surgical case volume increased significantly following the introduction of the bundle. There was no significant difference between the groups in respect to patient age, gender and Charlson Comorbidity Score. The post-bundled care cohort had a significantly shorter length of stay and more discharges directly home. THA patients were less likely to be readmitted or return to the emergency department within 30 days of procedure in the post-bundled care cohort. There was a significant difference in the average inpatient cost between groups with the post-intervention group costing close to 106$ more per case. The introduction of bundled funding maintained the quality of care in Ontario for patients receiving THA/TKA despite shorter lengths of stay in hospital and efforts to contain costs. A greater volume of procedures was performed for a set target price, allowing for optimal provincial funding planning. While the average cost of care increased in the post-bundle cohort, the inpatient cost of THA and TKA has remained essentially uniform since 2015. Outpatient arthroplasty has the potential to yield further cost savings if implemented correctly under the current bundle design.