Robotic-assisted unicompartmental knee arthroplasty improves implant positioning without reducing short-term complications: An overview of systematic reviews and a revised meta-analysis

Background and aims Unicompartmental knee arthroplasty (UKA) is a popular bone-preserving and ligament-preserving alternative to total knee arthroplasty (TKA) for isolated medial compartment osteoarthritis (OA). Robotic assistance aims to improve implant positioning accuracy and potentially reduce complications, although the evidence remains inconsistent across prior systematic reviews and meta-analyses. This review synthesizes evidence from existing systematic reviews and meta-analyses comparing robotic-assisted versus conventional UKA (C-UKA), focusing on complication rates and a revised meta-analysis is performed to determine whether robotics reduces complications. Methods This overview followed the Cochrane Handbook guidelines and was prospectively registered with PROSPERO CRD420251242811. Databases (PubMed, Scopus, Cochrane Library) were searched for systematic reviews/meta-analyses comparing robotic-assisted and conventional UKA in adults. Inclusion was limited to meta-analyses reporting complications, operative time, or malalignment. The AMSTAR‑2 was used to assess review quality and the GROOVE tool to evaluate primary study overlap. A revised meta-analysis was conducted in RevMan 5.4, using random-effects and fixed-effects models as appropriate, and calculating Mantel-Haenszel odds ratios (MH-OR) for complications and mean differences in operative time. Results Five meta-analyses were included in the study. Robotic-assisted UKA (RA-UKA) achieved significantly better component positioning within safe zones (RR 1.73, 95% CI 1.12–2.69, P = 0.01). Operative time was markedly longer (MD 16.90 min, 95% CI 13.91–19.90, P < 0.0001; I 2 = 0%). No significant difference emerged in overall complications (MH-OR 0.66, 95% CI 0.34–1.29, P = 0.22; I 2 = 89%). High primary study overlap and variable review quality (AMSTAR-2: 2 low, 1 moderate, 2 high risk of bias) were noted. Publication bias was low. Conclusion The use of RA-UKA enhances positioning precision but does not significantly reduce short-term complications compared to conventional UKA, despite increased operative time. High-quality, long-term RCTs are required to evaluate revision rates, survivorship and cost-effectiveness.