Fig. 2

Radiographic evaluation. A line from the superior to the inferior border of the articular surface (A–B line), and then a perpendicular line to the A–B line through the center of the humeral head (C–D line) are drawn. The angle (α) between this line and the line bisecting the humeral shaft (E–F line) was measured as the head–shaft angle. The distance between the tip of the proximal (s I), the medial (s IV) and the distal (s VI) head screw and the articular surface (d I, IV and VI) was measured. A line bisecting the blade (G–H line) and then a perpendicular line to the G–H line through the tip of the blade were drawn. D blade is the distance between the tip of the blade and the articular surface