Acromioclavicular Joint Injuries / “Shoulder Separations”

Acromioclavicular Joint Injuries / “Shoulder Separations”

The Acromioclavicular or AC joint is the small joint that connects the clavicle and the scapula. Injuries to the AC joint are often caused by a direct impact or a fall onto the outstretched hand. As a result, the clavicle (“collar bone”) and part of the scapula (acromion) are separated.

This type of injury may cause a small bump on the top of your shoulder. These types of injuries can also occur in high-impact sports like football or wrestling. While this is often treated non-surgically, Dr. Bercik performs arthroscopic AC repairs when needed.


  • Pain on the top of the shoulder over the AC joint
  • Limited mobility, especially at the end range of motion
  • Swelling and bruising over the AC joint
  • Deformation of the shoulder, causing a small bump
    on the top of the shoulder



Shoulder separations are commonly diagnosed through imaging of the AC joint.
Imaging will confirm the extent of the separation and dictate whether conservative or surgical intervention is necessary.


Depending on the extent of the separation, conservative care is often the first line of defense. Minor separations may heal in a few weeks, while full separations may need to be surgically repaired. Surgery may involve reconstructing the joint or trimming back the clavicle to allow the AC joint to heal properly and prevent arthritic changes to the joint. Conservative management will also help restore shoulder joint mobility with a physical therapist’s help.