The Financial Feasibility of Bilateral Total Knee Arthroplasty: A Matched Cohort Analyses of Revenue and Contribution Margin Between Simultaneous and Staged Procedures.

ABSTRACT

BACKGROUND: Financial analyses of simultaneous bilateral total knee arthroplasty versus staged bilateral total knee arthroplasty (simBTKA and staBTKA, respectively) have shown improved cost-effectiveness of simBTKA, though revenue and contribution margin (CM) for these procedures have not been investigated. Our analyses compared surgical outcomes, revenues, and CMs between simBTKA and staBTKA. METHODS: We retrospectively reviewed all patients who underwent simBTKA (both procedures done on the same day) and staBTKA (procedures done on a different day within one year) between 2012 and 2021. Patients were 11 propensity matched based on baseline characteristics. Surgical outcomes, as well as revenue, cost, and CM of the inpatient episode were compared between groups. Of the 2,357 patients evaluated (n = 595 simBTKA, n = 1,762 staBTKA), 410 were included in final matched analyses (205 per group). RESULTS: Total (P < .001) and direct (P < .001) costs were significantly lower for simBTKA procedures compared to overall costs of both staBTKA procedures. Significantly lower revenue for simBTKA procedures (P < .001), resulted in comparable CM between groups (P = .477). Postoperative complications including 90-day readmission (P = 1.000), 90-day revision (P = 1.000) and all-cause revision at latest follow-up (P = .083) were similar between groups. CONCLUSIONS: In our propensity-matched cohort, lower costs for simBTKA compared to staBTKA were matched by lower revenues, with a resulting similar CM between procedures. Given that postoperative complication rates were similar, both procedures had comparable cost-effectiveness. Future research is needed to identify patients for whom simBTKA may represent a better surgical intervention compared to staBTKA with respect to clinical and patient reported outcomes.