Comparative analysis of revision causes between robotic-assisted and conventional manual unicompartmental knee arthroplasty: a systematic review and meta-analysis

BACKGROUND: Robotic-assisted unicompartmental knee arthroplasty (R-UKA) is an emerging procedure; however, its benefits over conventional manual unicompartmental knee arthroplasty (C-UKA) are controversial, especially the revision and failure rates, and existing studies failed to reach a consensus on this issue. METHODS: The literature search was conducted on four databases (PubMed, Embase, Cochrane Library and Web of Science) from inception to 28 April 2025 according to the guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Eligibility criteria were studies that were written in English and reported any causes for a revision or failure subsequent to UKA with comparisons between R-UKA and C-UKA. The quality of each article was assessed using the Cochrane collaboration risk of bias tool or the Newcastle-Ottawa Scale. RESULTS: = 43%). Prosthesis loosening, infection, pain, and progression of disease were the main reasons for R-UKA revision, whereas for C-UKA revision, loosening, progression of disease, infection, and limb malalignment were the major causes. Loosening was the predominant reason in both groups across all follow-up periods; early revisions were also due to infection and disease progression. Within 2-5 years, the secondary reasons differed, being limb malalignment for C-UKA and pain for R-UKA. CONCLUSIONS: Compared with C-UKA, R-UKA may lower the risk of revision related to loosening, disease progression, and limb malalignment. Loosening remains the primary revision cause for both. Large-scale prospective trials with unified technical details are warranted to draw more rigorous conclusions in the future. TRIAL REGISTRATION: PROSPERO CRD420251042604.