120 patients were randomized to undergo total knee arthroplasty (TKA) with an intramedullary guide set at either a fixed femoral valgus angle (FVA) of 7 degrees compared to an FVA measured on long preoperative hip-knee-ankle radiographs. The purpose of this study was to determine if a preoperatively measured FVA provides more accurate mechanical alignment and individual component positioning, and improved clinical outcomes compared to a fixed FVA. Findings indicated that preoperative FVA measurements were comparable to fixed FVA patients in mean mechanical alignment, mean femoral and tibial component alignment, number of postoperative mechanical or tibial component alignment outliers, range of motion (ROM) and Knee Society Score (KSS) functional subscale scores. Number of femoral component alignment outliers were significantly higher and KSS objective subscale scores were significantly lower in the fixed FVA group compared to the measured FVA group.