File:Capture d’écran 2021-07-29 à 04.32.18.png

(A) Native shoulder. The center of rotation is in the humeral head, and the level of arm of deltoid does not allow consequent deltoid recruitment. (B) RSA with a medial glenoid/lateral humerus design in case of massive and irreparable rotator cuff lesion. Medialization of the center of rotation and humeral lateralization allows important deltoid recruitment. (C) Lateral glenoid/medial humerus RSA. As in native shoulders, the bony lateralization of the center of rotation decreases recruitment of the deltoid for rotation but allows for a retensioning of the rotator cuff.