Comparison of implant complications, lengths of stay, and costs among patients undergoing robotic-assisted versus conventional unicompartmental knee arthroplasty.

BACKGROUND

Adoption of robotic-assisted knee arthroplasty has increased and warrants a comprehensive understanding of early to mid-term implant complications. This study compared 2-year implant complications, lengths of stay (LOS), and reimbursements between robotic-assisted unicompartmental knee arthroplasty (RA-UKA) and manual UKA (M-UKA).

METHODS

A retrospective analysis of a national database identified patients who underwent primary robotic-assisted or manual UKA from 2010 to 2022. Patients undergoing RA-UKA were 1:5 ratio matched to M-UKA patients by age and comorbidities. Overall, 26,936 patients (RA-UKA = 4494; M-UKA = 22,442) were included. Multivariable logistic regressions computed odds ratios (OR) of 2-year implant complications. Costs were compared on the day of surgery and 90 days postoperatively. P values of 0.001 were significant.

RESULTS

There were no significant differences in implant-related complications between robotic-assisted UKA (RA-UKA) and manual UKA (M-UKA) including dislocations (0.11 % vs 0.20 %; OR: 0.55, P = 0.211), periprosthetic fractures (0.38 % vs 0.25 %; OR: 1.49, P = 0.148), aseptic loosening (1.40 % vs 1.13 %; OR: 1.24, P = 0.125), periprosthetic joint infections (1.58 % vs 1.36 %; OR: 1.16, P = 0.259), or revision surgeries (3.56 % vs 3.16 %; OR: 1.13, P = 0.164). RA-UKA was associated with a significantly shorter LOS (1.8 vs 2.1 days; P < 0.001) and higher median reimbursements on the day of surgery ($2858.00 vs $1665.00; P < 0.001) and 90-days postoperatively ($6243.50 vs $3320.00; P < 0.001).

CONCLUSION

RA-UKA demonstrated comparable implant-related complications to M-UKA two years postoperatively. Despite slightly shorter hospital stays for RA-UKA, higher median reimbursements occurred, warranting further cost-benefit analyses.

LEVEL OF EVIDENCE: III.