Femoral component size selection during total knee arthroplasty should not vary from surgeon to surgeon for patients with the same bone size. This study explored if systematic variations in femoral component size selection exist. Thirteen surgeons' choices of femoral component size (Duracon, n = 1388; Triathlon, n = 740) were analyzed using a generalized linear model with femoral component size as the dependent variable and surgeon identification, years in practice, and adult reconstruction fellowship training as the independent variables. The model adjusted for differences in bone size. It was found that more experienced surgeons implant larger femoral components. New instruments and training protocols may be necessary to adjust for surgeon experience.