Editorial Commentary: Partial Rotator Cuff Repair and Deltoid Retraining Shows Positive Outcomes for Large to Massive Rotator Cuff Tear.

In terms of rotator cuff repair, there is a goal for complete repair and healing, as rotator cuff integrity correlates with clinical and functional results. Retear has been shown to have a significant influence on progression toward osteoarthritis, and patients with an intact supraspinatus show superior abduction and flexion strength. However, in cases where complete repair may not be possible and/or cost limitations may prohibit augmentation, partial repair can provide a respectable outcome. Furthermore, regardless of healing status, partial repair may provide satisfactory relief for patients to still achieve the minimally clinically important difference threshold based on patient-reported outcomes. As introduced by Burkhart, repairing the tear margin and the transverse force couple (subscapularis and/or infraspinatus tears, if present) establishes a "suspension bridge" mechanism for force transmission, effectively creating a "functional cuff tear" by minimizing the defect size and allowing for a balanced shoulder joint with a stable fulcrum. A deltoid retraining program following a partial rotator cuff repair can restore range of motion and strength to the shoulder as alternative muscle activation (latissimus dorsi and teres major) in unison with the deltoid can compensate for the partial tear to limit superior migration of the humeral head and generate a stable glenohumeral fulcrum in cases of large to massive rotator cuff tears. Ultimately, as the rates of shoulder arthroplasty increase in patients under 50 years of age, in terms of societal burden, surgeons should consider joint-sparing techniques such as partial repair.