289 Blood Loss in Robotic-Assisted Knee Arthroplasty: A Retrospective Analysis

Abstract Introduction Significant blood loss is associated with a delayed postoperative recovery in joint arthroplasty. Emerging evidence suggests robotic-assisted knee arthroplasty reduces soft-tissue trauma, length of stay, and can facilitate a faster recovery. This study compares the total blood loss in patients undergoing robotic-assisted knee arthroplasty compared to conventional methods. Method Patients undergoing robotic-assisted total knee arthroplasty (TKA) or unicomparmental knee arthroplasty (UKA) were identified using patient records. Robotic-assisted groups were compared against contemporary sex-matched controls undergoing jig-based arthroplasty. The mean total blood loss was estimated using the Gross equation. Statistical significance was identified using the Student's t-test and Mann-Whitney U test for parametric and non-parametric data, respectively. Results Robotic TKA and UKA groups were successfully matched to contemporary controls (n = 50 in all groups). No differences in preoperative haematological parameters or blood volume were found between the robotic-assisted and control groups. Robotic TKA experienced 23.7% less blood loss compared to control TKA (911.0ml vs 1193.7ml, p < 0.01) which was found to be statistically significant. There was a non-significant difference in mean total blood loss in robotic UKA compared to control UKA (821.7ml vs 854.7ml, p = 0.69). Conclusions The use of a robotic surgical system reduces blood loss in TKA but not UKA in knee arthroplasty.