Ninety patients with large (3–5 cm) and massive (>5 cm) rotator cuff tears were randomized to undergo arthroscopic repair with SLRS (n=26), KD (n=26), or KL (n=24). The primary outcome was retear rate at one year, assessed by 3T MRI. Secondary outcomes included range of motion (ROM), ASES, Constant, UCLA, and VAS scores, measured up to a mean of 20–21 months. Overall, all three groups experienced significant postoperative improvement in functional scores and ROM, with no significant differences between groups. However, retear rates were significantly higher with SLRS (38%) compared with KD (9.5%) and KL (11.7%) (p=0.04). These findings suggest that although SLRS provides comparable clinical improvement, its higher risk of retear limits its utility for acute large-massive tears.