Injury to the anterior cruciate ligament (ACL) of the knee is the most common ligament injury that requires operative treatment. Patient treatment can be non-operative and operative. So far, multiple ACL reconstruction (ACLR) techniques using a variety of graft types and implants that fixate the grafts have been described. Since 1995, titanium buttons with a loop have been used as implants for suspensory fixation of the graft in the femoral tunnel during ACLR. There are two types of titanium buttons in use: one with a fixedlength loop and the other with an intraoperative adjustable-length loop. This randomized prospective study presents a comparative analysis of results after ACLR using two implant types for suspensory graft fixation in the femoral tunnel. The post-operative knee stability was assessed 24 months after surgery using the Lachman test and the lateral pivot shift test, as well as the KT-1000 arthrometer test. In patients whose graft was fixated using a fixedlength loop implant, the mean post-surgery knee stability, measured with the KT-1000, was 1.167 +/-0.780; in patients whose graft was fixated using an adjustable-length loop implant, the mean value was 1.100+/-0.894 (P=0.605). The mean post-surgery IKDC score for the fixed-length loop group was 84.887 +/-9.0207, while for the adjustable-length loop the score was 88.327 (+/-7.302). The mean Lysholm score was 93.50+/-6.872 for the fixedlength loop group of patients and 94.00 +/-5.527 for the adjustable-length loop group. The results of this study lead to a conclusion that both types of implants can be used with success during ACLR, because the functional results of operative treatment using both implants were identical after surgery.