80 patients who had experienced a primary unilateral anterior cruciate ligament (ACL) injury were randomly assigned into 1 of 2 groups to compare femoral tunnel aperture shape and femoral tunnel position. Patients received either a transportal (group 1) or outside-in (groups 2) technique for ACL reconstruction. The results of the study indicated that the transportal (TP) technique led to a more ellipsoidal anteromedial (AM) femoral tunnel aperture than the outside-in (OI) technique, and that mean posterolateral femoral tunnel position with the OI technique was significantly shallower, with more variable/perpendicular aperture axis angle to the femoral shaft axis than the TP technique.