Assessing the Impact of Robotic-assisted Total Knee Arthroplasty on Quality of Life and Mental Health: A Matched Cohort Study.

Background: Whether the implementation of robotic-assisted technology in total knee arthroplasty (Ra-TKA) translates into better clinical results remains uncertain. We investigated the impact of Ra-TKA on quality of life and mental health as measured by patient-reported outcome measures (PROMs).

Materials and methods: In this retrospective review, a consecutive series of 204 patients who underwent Ra-TKA were matched by age, sex, and body mass index in a 1:1 ratio to conventional TKAs. The primary outcome was improvement in Knee Injury and Osteoarthritis Outcome Score (KOOS) and Veterans RAND 12-Item Health Survey (VR-12) as measured by minimal clinically important difference (MCID) and patient acceptable symptom state (PASS) scores. Secondary outcomes included hospital length of stay (LOS), skin-to-skin time, tourniquet time, and active knee range of motion. Bivariate analyses were performed between groups.

Results: A total of 314 patients (Ra-TKA=156; TKA=158) had 1-year PROMS available and were included in the study. Conventional TKA patients had significantly longer LOS and shorter skin-to-skin time and tourniquet time (all P<0.001) than Ra-TKA patients. More patients achieved full extension in the Ra-TKA cohort, but both groups ended up with similar postoperative PROMs at 1-year follow-up. A higher number of patients achieved the VR-12 mental component score MCID in the conventional TKA group compared to the Ra-TKA group (50.3% vs 29.5%, P<0.001).

Conclusion: Our results suggest Ra-TKA results in shorter LOS and better short-term knee extension but no improvement in joint-specific PROMs. Additionally, the association between lower quality of life, mental health outcomes, and Ra-TKA may be mediated by patient expectations. Therefore, documenting the use of Ra-TKA is important when reporting these quality metrics.