Forty male patients with complete distal biceps tendon ruptures were randomized to undergo repair with either onlay fixation using suture anchors (n=20) or inlay fixation using a bicortical button (n=20). The primary outcome was supination peak torque recovery, assessed preoperatively and at ≥6 months postoperatively at 45°, 90°, and 120° of elbow flexion. Secondary outcomes included comparison with the contralateral arm, strength changes across elbow positions, and complication rates. At follow-up, 34 patients were analyzed (17 in each group). Both groups demonstrated >100% recovery of supination strength relative to preoperative injured-limb values, with no significant differences between fixation techniques. Overall, the results revealed that both inlay and onlay fixation yielded comparable and excellent recovery of supination torque. These findings suggest that either technique can be effectively used depending on surgeon preference and contextual factors.