80 patients scheduled for total knee arthroplasty were randomized to the surgery with the use of either imageless navigation or conventional extra- and intramedullary instrumentation. The purpose of this study was to compare radiographic and clinical outcomes over a minimum of 9-year follow-up. Data demonstrated a significantly lower incidence of mechanical axis outliers (varus or valgus deviation exceeding 3 degrees from neutral) with imageless navigation compared to conventional instrumentation, though no significant differences in clinical outcome measures or range of motion were observed between groups after a minimum of 9 years.