Robotic-assisted versus conventional total knee arthroplasty: an updated systematic review and meta-analysis of randomized controlled trials with grade assessment

Robotic-assisted total knee arthroplasty (RTKA) has been increasingly adopted to improve surgical precision during primary TKA. Although previous evidence suggests that RTKA may reduce alignment variability and radiographic outliers, whether these technical advantages translate into clinically meaningful improvements over conventional TKA (CTKA) remains uncertain. This review evaluated whether the technical advantages of RTKA translate into clinically meaningful benefits over CTKA. Electronic databases were systematically searched from inception to 17 May 2026 for randomized controlled trials (RCTs) comparing RTKA with CTKA in primary TKA. The protocol was registered with PROSPERO (CRD420261413342). Primary outcomes were radiographic alignment accuracy and alignment outliers; secondary outcomes included patient-reported, functional, perioperative, technical, biological, and safety outcomes. Random-effects meta-analyses were performed using mean differences (MDs), standardized mean differences (SMDs), or risk ratios (RRs) with 95% confidence intervals (CIs). Risk of bias was assessed using RoB2, and certainty of evidence was evaluated using GRADE. This study received no external funding. Thirty-five papers representing 31 studies and reporting data for 4086 participants were included. RTKA reduced HKA deviation (MD − 0.83°; 95% CI − 1.06 to − 0.60) and HKA outliers (RR 0.35; 95% CI 0.25 to 0.47), as well as CTCA deviation (MD − 0.46°; 95% CI − 0.67 to − 0.25) and several component-alignment outlier rates. However, CFCA, SFCA, and STCA mean deviations did not differ significantly between techniques. Patient-reported, functional, biological, technical, and safety outcomes were broadly comparable, and isolated secondary differences were considered exploratory. RTKA was associated with longer operative time on average (MD 20.85 min; 95% CI 14.55 to 27.16; PI − 9.17 to 50.87), whereas intraoperative blood loss, length of hospital stay, and overall adverse events were comparable. Possible small-study effects were identified for selected radiographic outcomes, with sensitivity of the SFCA-deviation estimate to trim-and-fill adjustment. The certainty of evidence varied from very low to high, with most assessments rated as low or very low. RTKA improves selected radiographic alignment outcomes and reduces alignment outlier rates compared with CTKA, but these technical advantages have not consistently translated into broad clinical superiority. RTKA was associated with longer operative time on average, whereas blood loss, hospital stay, and overall adverse events were comparable. RTKA should therefore be considered a tool for improving surgical precision, with adoption individualized according to patient-specific surgical requirements, surgeon expertise, robotic platform, and institutional resources.