BackgroundThe purpose of our present work was to compare robotic-assisted UKA and conventional UKA regarding the clinical and radiographic results at 5-year follow-up.MethodsForty-one medial UKAs were conducted with robotic assistance (group ROA) between January 2010 and January 2015, and these subjects were matched with 44 subjects undergoing medial UKAs using the same prosthesis, implanted by conventional technique (group CON). In a 5-year follow-up, subjects were clinically evaluated by using Knee Society functional (KSF), Knee Society clinical (KSC), and Knee Society pain (KSP) scores. Radiographic assessments with regards to coronal mechanical axis (CMA) and condylar twist angle (CTA) were compared between group ROA and group CON.ResultsIn the evaluation, the mechanical limb alignment was significantly increased after operation in each group. The implantation accuracy of the coronal mechanical axis was similar in both groups. As for the evaluation of femoral rotation, the internal rotation in group ROA was remarkably less than that in group CON. The difference was not significant in KSP, KSF, KSC scores between group ROA and group CON.ConclusionOur results showed that robotic assistance improves component position without gaining superior CMA or increasing clinical results versus conventional UKA at 5-year follow-up. To conclude, using robotic assistance in UKA is recommended as compared to conventional UKA. Long-term follow-up will be needed to draw conclusion about the overall outcomes of robotic assistance as compared with conventional technique.Trial registrationCurrent Controlled Trials ChiCTR2000033918. Registered 16 June 2020.