What are the benefits of robotic-assisted total knee arthroplasty over conventional manual total knee arthroplasty? A systematic review of comparative studies

Total knee arthroplasty (TKA) is a highly successful operation that improves patients' quality of life and functionality. Yet, up to 20% of TKA patients remain unsatisfied with the functional outcomes. Robotic TKA has gained increased attention and popularity in order to improve patient satisfaction and implant survivorship by increasing accuracy and precision of component implantation. The current systematic review was run in order to compare implant survivorship, complication rates, clinical outcomes, and radiological outcomes between robotic-assisted TKA (RA) and conventional manual TKA (CM). Articles were referenced from the US National Library of Medicine (PubMed/MEDLINE), EMBASE, and the Cochrane Database of Systematic Reviews. Nine comparative studies with 1199 operated knees in 1159 patients were included, 614 underwent active or semi-active robotic-assisted TKA compared to 585 CM-TKA. Improvements in the RA group were reported for early functional outcomes, radiographic outliers (RA 16% vs CM 76%) and radiolucent lines (RA 0% vs CM 35%). No significant differences between the two groups were reported in overall survivorship (RA 98.3% vs CM 97.3%), complication rate (RA 2.4% vs CM 1.4%) and operative time (RA 88 min vs CM 79 min). Despite higher costs, robotic-assisted TKA offers better short-term clinical outcomes when compared to conventional manual technique with reduction in radiographic outliers and reduced risks of iatrogenic soft tissues injuries (reduced blood loss and postoperative drainage). Further high-quality long-term studies of modern robotic systems are required in order to evaluate how the increased accuracy and reduced outliers affect the long-term survivorship of the implants and the clinical outcomes.