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 the 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 utilized 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.