Can a Reduction in Revision Rates Make Robotic Total Knee Arthroplasty Cost Neutral With Manual Total Knee Arthroplasty at Ten-Year Follow-Up? An Episode Cost Analysis

Background: Advocates of robotic total knee arthroplasty (RTKA) suggest that its greater cost may be recaptured through a reduction in revision rates. We sought to determine what reduction in revision TKA would be required for RTKA to become cost neutral with manual TKA (MTKA). Methods: Episode costs were determined for 2392 RTKAs and 2392 MTKAs. Mean total cost of revision TKA in our health system was identified. Episode cost difference of the RTKA and MTKA cohorts was divided by the mean cost of revision TKA to estimate the reduction in revisions required to make RTKA cost neutral with MTKA. The National Joint Registry was consulted to determine the cumulative revision rate for the implant used in this study. Results: Episode cost for the RTKA cohort was $5.7M greater than MTKA. Mean acute stay cost for revision TKA was $20,972, but post-acute costs were not available. If post-acute costs for revision TKA are conservatively estimated at 50% of episode cost (ie, episode cost = $41,944), 131 revision TKAs would need to be prevented in the RTKA cohort to make it cost neutral with MTKA. The National Joint Registry cumulative revision rate for this implant is 3.37% at 10 years, thus only 81 revisions would be expected per cohort. Conclusion: Our data suggest that it is not possible for RTKA to achieve cost parity with MTKA through a reduction in revision rate alone. Future price reductions may make the cost comparison more favorable. In addition, demonstration of improved patient outcomes would undeniably add value to RTKA and change the analysis. (C) 2021 Elsevier Inc. All rights reserved.