Robotic Navigation in Minimally Invasive Total Knee Arthroplasty: An Updated Open-Source Systematic Review of Precision, Recovery and Functional Outcomes

Abstract

Background: Robotic assistance and minimally invasive exposure are distinct components of total knee arthroplasty (TKA). Improved implant positioning cannot, by itself, establish less surgical trauma or better patient-reported recovery. This review examined their comparative effects while separating directly relevant limited-exposure studies from contextual allocated trials. Methods: A bounded, open-source web search was conducted on 12 September 2026 for reports first published between 1 January 2021 and 15 July 2026. Comparative minimally invasive studies and randomised or quasi-randomised primary-TKA trials were eligible in separate strata. One reviewer performed screening, extraction and domain-based risk-of-bias assessment. Findings were synthesised without meta-analysis. Results: Ninety-seven returned record instances represented 65 unique records. Thirty-one reports were sought, 13 were retrieved and eight reports were included, mapping to seven study identifiers. Eighteen potentially eligible reports were not retrieved. Two retrospective reports directly examined modified-subvastus TKA; their populations may overlap. In the clearest same-approach comparison, robotic surgery was associated with 0.40-point lower day-1 pain and 5.20 degrees greater day-14 flexion, but 21.75 minutes longer surgery. Contextual trials generally favoured selected radiographic measures without establishing durable functional superiority. Reporting inconsistencies, predictable allocation, post-allocation exclusions and inaccessible reports materially limited confidence. Conclusions: Retrieved evidence supports robotic assistance as a possible precision-enhancing adjunct, not as established proof of superior minimally invasive recovery, long-term function or safety. Direct clinical evidence is very uncertain. Conclusions apply to the accessible corpus rather than to the entire eligible literature.