A 90-Day Episode-of-Care Cost Analysis of Robotic-Arm Assisted Total Knee Arthroplasty

Abstract

Introduction One way to potentially help contain the rising healthcare costs is the utilization of technological advances, such as robotic-assistive technology, for total knee arthroplasty (TKA). Therefore, the purpose of this study was to perform a cost analysis between robotic-arm assisted TKA and manual TKA (mTKA) techniques. Specifically, we compared: 1) 90-day EOC costs, as well as several variables within the episode, including 2) index costs; 3) index lengths-of-stay (LOS); 4) discharge disposition; and 5) readmission rates. Methods A retrospective claims analysis was performed on Medicare FFS beneficiaries who underwent rTKA and mTKA procedures between January 1, 2016 and March 31, 2017. Patients were matched rTKA to mTKA in a 1-to-5 ratio, yielding 519 rTKAs and 2,595 mTKAs. The overall 90-day EOC costs, including the index procedures, LOS, discharge dispositions, and readmissions were compared between cohorts. Results Overall 90-day EOC costs ($18,568 vs. $20,960) as well as index facility costs ($12,384 vs. $13,024; p=0.0001) were found to be less than that for rTKA vs. mTKA. rTKA also accrued $1,744 fewer costs than mTKA (5,234 vs. $6,978; p=<0.0001) utilized fewer days in inpatient (4 vs. 7; p<0.0001) and SNF care (15 vs. 16; p=0.0642) as well as a 90-day readmission reduction of 33% (p=0.0423). Discussion The results from this study show rTKA to be associated with significantly lower 90-day EOC costs. These lower rTKA patient costs are likely attributable to the significantly lower index costs, increased likelihood of being discharged to home, shorter LOS, and decreased readmission rates, when compared to mTKA patient costs.