Fig. 7-A.

The 40/50/60 rule. The reconstruction should allow 40° of external rotation with the subscapularis approximated, 50% posterior translation of the head on the glenoid, and 60° of internal rotation of the arm abducted to 90°. (Reproduced, with permission of Elsevier, from: Matsen FA 3rd, Clinton J, Rockwood CA Jr, Wirth MA Lippitt MA. Glenohumeral arthritis and its management. In: Rockwood CA Jr; Matsen FA 3rd; Wirth MA; Lippitt SB, editors. The shoulder. 4th ed. Philadelphia: Saunders; 2009.)