Compensatory Load Sharing by Residual Rotator Cuff Subregions Preserves Glenohumeral Mechanics in Partial and Massive Tears

These findings support targeted strengthening of the posterior cuff in patients with partial or early-stage massive RC tears to help maintain joint congruency, minimize abnormal glenohumeral contact mechanics and humeral head translation, and potentially delay the progression to cuff tear arthropathy. Surgical repair, particularly of the SSC, may be required in advanced tears to fully restore force coupling and load distribution.