107 patients who were scheduled to undergo total knee arthroplasty (TKA) were randomized to receive either computer assisted surgery, intramedullary guides for the femur and tibia, or an intramedullary guide for the femur and an extramedullary guide for the tibia. The results of the study indicated that patients randomized to the computer assisted group had much more accuracy in terms of alignment of the coronal tibiofemoral and coronal tibiofemoral angle. However, it was also found that the computer assisted procedure was significantly longer than the other two interventions.