Jo CH, et al. - In order to find out the mid-term safety and efficacy of an intratendinous injection of autologous adipose tissue–derived mesenchymal stem cells (AD MSCs) for rotator cuff disease, researchers conducted a 2-year follow-up study to include a total 19 individuals with partial-thickness rotator cuff tears. They measured clinical outcomes according to pain, range of motion, muscle strength, functional scores, overall satisfaction and function, and presence of failure. No treatment-related adverse events were noted at minimum 2-year follow-up. For the treatment of partial-thickness rotator cuff tears, this study revealed continued safety and efficacy of an intratendinous injection of AD MSCs over a 2-year period through regeneration of tendon defects.