The mini-subvastus surgical technique avoids both quadriceps arthrotomy and patella eversion. Since March 2003, this quad-sparing minimally invasive surgical (MIS) technique has been applied to more than 98% of our primary total knee arthroplasty (TKA) patients. This study compares our first 150 MIS TKA patients to our previous 150 traditional TKA patients. Quadriceps recovery was rapid in the MIS group with 83% able to do a straight leg raise the day after surgery. Hospital length of stay was decreased in the MIS group, 3.4 days, vs the traditional group, 4.1 days (P = .00013). Fewer MIS patients required skilled nursing or rehabilitation center admission. Increased knee flexion was seen for the MIS patients throughout the first 2 years of follow-up. Mean knee flexion at 1 year was 127 degrees for the MIS patients vs 114 degrees in the traditional TKA patients (P < .0001). Comparison between the MIS and traditional techniques demonstrated no increase in the number or severity of complications and no difference in operating room time.