From the case:
Glenoid version measurement: scapular blade method (diagram)
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Info

Version angle (red) = 90o - angle between scapular and glenoid lines
scapular line (yellow) joins the midpoint of the glenoid line to the long axis of scapular blade
glenoid line (blue) at the mid-glenoid level, joins the anterior and posterior margins of the glenoid rim
Case Discussion
Glenoid version:
- range of normal is 0-7o
- neutral version is 0o
- retroversion is > 7o which is associated with posterior glenohumeral instability and posterior labral tears