Robotic-Arm Assisted Total Knee Arthroplasty: Cost Savings Demonstrated at One Year

Purpose: Robotic-arm assisted total knee arthroplasty (RATKA) has the potential to enhance radiographic, clinical, and patient-reported outcomes. The purpose of this study was to compare resource utilization, episode-of-care (EOC) costs, readmissions, and complications of robotic-arm assisted total knee arthroplasty (RATKA) and manual TKA (MTKA).

Methods: TKA procedures were identified from a private payer claims database. RATKA procedures required both a robotic arm-assisted procedure code and a 60-day pre-operative computed tomography scan. Propensity score matching (1:5 RATKA to MTKA) was performed, based on various patient characteristics and comorbidities. After matching, 4452 patients (742 RATKA and 3710 MTKA) were analyzed for 90-day and one-year EOC costs, index TKA costs, lengths of stay (LOS), discharge statuses, rehabilitation utilizations, as well as 90-day and one-year readmissions- and knee-related complications.

Results: RATKA patients had shorter LOS (mean 1.56 versus 1.91 days; p < 0.001), lower index costs by $1762 ($32,747 versus $34,509; p = 0.003), and higher discharges to home rates (51.8 versus 47.8%; p = 0.049) than MTKA patients. RATKA patients had less 90-day (68.5 versus 72.0%; p = 0.048) and one-year (70.8 versus 75.0%; p = 0.016) home health utilizations. The RATKA cohort had lower 90-day ($39,260 versus $41,458; p = 0.001) and one-year ($51,462 versus $54,171; p = 0.011) EOC costs. No significant differences in readmission and overall complication rates were observed (p > 0.05).

Conclusion: RATKA was associated with lower index costs and EOC costs at both 90 days and one year. These patients had shorter LOS, were discharged home more frequently, and used less home health services. Cost savings were demonstrated for RATKA beyond the 90-day period with an increase in savings between 90-day and one-year time points. These data may be of importance to payers and providers interested in the longer-term value of RATKA.