Blood loss and transfusion risk in robotic-assisted knee arthroplasty: A retrospective analysis

BACKGROUND The purpose of this study was to compare total blood loss and the risk of receiving a blood transfusion in robotic-assisted total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) against conventional jig-based techniques. METHODS Robotic TKA (n = 50) and UKA (n = 50) patients were matched to contemporary controls for TKA (n = 50) and UKA (n = 50) and retrospectively analysed. RESULTS Robotic TKA patients experienced 23.7% less blood loss compared to conventional TKA patients (911.0 ml vs 1193.7 ml, p < 0.01), and were associated with an 83% relative risk reduction of receiving a transfusion (2% of patients vs 12%, p = 0.02). Robotic UKA patients did not demonstrate less blood loss compared to corresponding controls (821.7 ml vs 854.7 ml, p = 0.69). Both UKA groups received no transfusions. CONCLUSIONS Robotic surgical systems in TKA reduces blood loss and lowers the risk of requiring a blood transfusion. In UKA, robotic-assisted arthroplasty did not reduce blood loss compared to conventional arthroplasty.