One hundred twenty-four patients with full-thickness medium-to-large posterosuperior nonacute rotator cuff tears were randomized to receive transosseous-equivalent (TOE) repair alone (n=63) or TOE repair augmented with a bioinductive collagen implant (BCI) (n=61). The primary outcome was retear rates, evaluated via MRI at 12 months. Secondary outcomes included tendon thickness, structural integrity, and clinical measures such as pain and functional scores. At one year, the BCI group demonstrated a significantly lower retear rate (p=0.010) and improved tendon structural quality. Clinical outcomes improved in both groups without differences between them. Overall, the study revealed that BCI augmentation reduces retear rates without increasing complications, though clinical outcomes were similar at one year.