Post-operative outcomes, including opioid utilization and length of stay, following total knee arthroplasty: A retrospective case matched series comparing conventional and robotic-assisted total knee arthroplasty

Keywords Total Knee Arthroplasty, robotic-assisted, opioid use Background With the rise of robotic arm-assisted total knee arthroplasty (TKA) cases, there is a need to determine if there are clinical benefits associated with this technology. The purpose of this study was to further evaluate if robotic-assisted TKAs result in improved inpatient post-operative outcomes compared to conventional TKAs. Materials and Methods After IRB approval, a retrospective chart review of 100 robotic-assisted primary TKAs and 100 matched controls undergoing conventional TKA was performed. Patients underwent primary TKA from 2016 to 2018 with minimum 6-month postoperative follow-up by a single fellowship-trained arthroplasty surgeon at a high-volume joint center. Exclusion criteria included <6 month postoperative follow-up, incomplete chart information, inflammatory arthritis, and BMI >40. Demographics and post-operative outcomes, including length of stay (LOS), opioid consumption, duration of opioid use, and discharge status, were recorded. Results There were no significant differences in pre-operative demographics between the two groups. A decrease in LOS (1.58 vs. 2.18 days, p < 0.001) and morphine equivalents (73.52 vs. 102.50, p = 0.017) was reported for the robotic TKA group compared to the control group. The robotic group also reported fewer patients at six weeks postoperatively requiring opioids compared to the control group (37 vs. 61, p = 0.001). Average KOOS Jr at 6-months postoperatively was 81.73 for the control group and 78.22 in the robotic group (p = 0.039). Conclusion Robotic-assisted TKA patients experienced significantly decreased LOS, morphine equivalents, and opioid usage at 6-week postoperatively, indicating that there are early clinical benefits of robotic-assisted TKA. No significant differences between the robotic and control groups were reported in pre-operative KOOS Jr. Although average 6-month postoperative KOOS Jr was slightly higher for the control group, the difference was clinically insignificant. Our average KOOS Jr for both cohorts was higher than the national 1-year postoperative average, 76.8.