Acromiohumeral distance measured on conventional radiography :
- Anteroposterior radiographs with the arm in neutral position
- Beam angled 20° craniocaudally
- Humeral head centered in the glenoid fossa, and acromion profiled.
- Patient in the upright position.
- Measurement performed from the dense cortical bone at the inferior aspect of the acromion to the subchondral lamina of the humeral head.
Normal : 7-15 mm
If < 7 mm : full-thickness supraspinatus tendon tears present in 90%
Ref : Saupe N, Pfirrmann CWA, Schmid MR, Jost B, Werner CML, Zanetti M. Association between rotator cuff abnormalities and reduced acromiohumeral distance. AJR 2006;187 : 376-382
Rotator cuff rupture