A
A Hill-Sachs lesion whose width is strictly greater than the percentage of anterior glenoid bone loss.
B
A bipolar lesion where the combined bone loss exceeds 10% of the humeral head radius.
C
A Hill-Sachs lesion whose medial margin extends medial to the measured glenoid track.
D
A glenoid defect that measures > 25% of the inferior glenoid diameter.
Explanation:The glenoid track is calculated as 83% of the normal glenoid width minus the anterior bone loss. If the medial margin of the Hill-Sachs lesion lies medial to this track, it will engage the anterior glenoid rim during abduction and external rotation (off-track), requiring a Remplissage or bone block procedure. Reference: Di Giacomo et al., 'Clinical release of the glenoid track concept...', Am J Sports Med (2014).