Over the past two decades, arthroscopic rotator cuff repair has become the most commonly performed surgical treatment for rotator cuff disease with significant clinical results. However, despite improvements and refinements in arthroscopic surgery, the rate of tendon nonunion after repair remains between 20 and 94%. Several studies have shown significant rotator cuff repair results when the tendon is healed. Therefore, the main goal of surgery is to obtain a high rate of tendon healing. Many factors influence tendon nodal healing after repair. Early rehabilitation activities may be a factor, but usually it is the prevention of postoperative joint stiffness. Some animal studies have shown that early activity leads to strain and micromotion at the repair, which affects healing, while post-repair braking promotes tendon bone healing. In contrast, another animal study found that continuous passive activity contributed to tendon bone healing. Thus, animal studies did not find an ideal method to promote tendon healing. Controlled clinical studies have also yielded conflicting results.