Fig. 1
From: The effect of medial calcar support on proximal humeral fractures treated with locking plates
a The distance between the most cranial screw and humeral articular distance is measured in external rotation A-P view 1 day postoperatively (X = 13.51 mm). b 12 months postoperatively, the distance between the screw tip and articular surface is measured in the same method (X = 10.09 mm). The amount of head impaction is 13.51 mm–10.09 mm = 3.42 mm in this patient