Felsch Q, Mai V, Durchholz H, et al. - This research was sought to present complications after arthroscopic rotator cuff repairs (ARCRs) from a large patient cohort based on the clinical application of a newly-defined core event set (CES) and severity grading. Between 2010 and 2016, consecutive primary ARCRs documented in a local clinical registry were enrolled. Researchers documented 1,661 repairs in 1,594 patients (mean, 57 years [standard deviation, 9]; 38% women); 21% involved partial tears. According to the CES and severity grading, comprehensive local AE documentation was possible and exhibited that about 1/5 of ARCRs were affected, mostly by one AE of low severity. It was noted that shoulder stiffness was the most frequent event.