This proposal's objective is to challenge and expand the current definition of rotator cuff healing by investigating tendon retraction - broadly defined as medial translation of the repaired tendon away from the bone with or without a defect - as a common and clinically predictive structural outcome following rotator cuff repair. The investigators' central hypothesis is that failure with continuity is a common yet unrecognized structural phenomenon of rotator cuff healing that is significantly and meaningfully correlated with clinical outcomes. The investigators' approach is to characterize tendon retraction using an array of implanted radio-opaque markers, and investigate its relationship to pre-operative tissue quality (MRI), post-operative repair structural integrity (MRI) and clinical outcomes in a 125-patient prospective cohort study. These patients will complete (1) validated questionnaires and range of motion testing pre-operatively, (2) CT imaging at day of surgery, 3 weeks, and 3, 6, 12 and 24 months post-operatively, (3) MRI at 3 weeks and 3, 6, 12 and 24 months post-operatively and (4) questionnaires, range of motion and strength testing at 3, 6, 12 and 24 months post-operatively.