Robotic Arm-Assisted Knee Surgery: An Economic Analysis

OBJECTIVES: Previous studies on Medicare populations have shown improved outcomes and decreased 90-day episode-of-care costs with robotic arm-assisted total knee arthroplasty (RATKA). The purpose of this study was to evaluate expenditures and utilization following RATKA in th population younger than 65 years. STUDY DESIGN: This is a retrospective longitudinal analysis of a commercial claims data set. METHODS: TKA procedures were identified using the Optuminsight Inc database. The procedures were stratified in 2 groups: the RATKA and manual TKA (MTKA) cohorts. Propensity score matching was performed at 1:5. Utilization and associated costs were analyzed for 90 days following the index procedure. A total of 357 RATKA and 1785 MTKA procedures were included in this analysis. RESULTS: Within 90 days post surgery, patients who had RATKA were less likely to utilize inpatient services (2.24% vs 4.37%; P=.0444) and skilled nursing facilities (1.68% vs 6.05%; P<.0001). No patients in the RATKA group went to inpatient rehabilitation, whereas 0.90% of the MTKA arm went to an inpatient rehabilitation facility. Patients who utilized home health aides in the RATKA arm utiliz significantly fewer home health days (5.33 vs 6.36 days; P= .0037). Costs associated with overall postsurgery expenditures were $1332 less in the RATKA arm ($6857 vs $8189; P=.0018). The 90-day global expenditures (index plus post surgery) were $4049 less in the RATKA arm ($28,204 vs $32,253; P< .0001). Length of stay after surgery was nearly a day less for the RATKA arm (1.80 vs 2.72 days; P< .0001). CONCLUSIONS: RATKA was associated with shorter length of stay, reduced utilization of services, and reduced 90-day payer costs compared with MTKA.