Acromioclavicular joint series

The acromioclavicular (AC) joint radiographic series is used to evaluate the acromioclavicular joint and the distal clavicle.


AC radiographs are performed for a variety of indications including:

  • shoulder trauma
  • direct blows to the shoulder region
  • following a fall onto an adducted arm
  • suspected dislocation
  • suspected arthritis


Standard projections
  • AP view
    • erect view demonstrating the AC joint in the anteroposterior plane
    • best view to inspect widening of the AC joint
Additional projections
  • AP with weight bearing
    • also known as a stress view, the patient holds onto a weight on the affected side, placing inferior pressure on the AC joint
    • this view is used to rule out displacement when it is suspected yet not confirmed on the AP view
  • AP comparison views
    • both AC joints are imaged separately, to rule out a suspected displacement or differentially anatomical variation
  • Zanca view
    • AP projection with a 10-15 degree cephalad angle to free the AC joint from superimposition 
Imaging the shoulder
Radiographic views