Acromioclavicular joint cyst

Last revised by Mohamed Saber on 6 Nov 2023

Acromioclavicular joint cysts are benign lesions, either ganglionic or synovial in etiology.

Soft, slightly painful mass above the acromioclavicular joint, sometimes slightly limiting shoulder range of motion.

Classified into two types according to their etiology 3:

  • type 1: in advanced acromioclavicular joint arthritis without rotator cuff tear from degenerative changes in the acromioclavicular joint causing irritation of the synovium, with overproduction of fluid and subsequent formation of superficial cysts at the joint

  • type 2: in chronic rotator cuff tear with superior migration of the humeral head, resulting in irritation and deterioration of the acromioclavicular joint capsule; increased synovial fluid production causes glenohumeral joint fluid to leak into the communicating acromioclavicular joint to produce cysts (Geyser sign)

Swelling of the acromioclavicular joint that shows arthritic changes.

Anechoic formation, sometimes sepimented, over the acromioclavicular joint, without blood flow.

High T2 signal in homogeneus multilocular mass on the acromioclavicular joint.

The treatment of AC joint ganglion cysts can be either conservative or surgical, with surgical options including:

  • type 1: surgical excision with resection of the lateral clavicle

  • type 2: reverse shoulder arthroplasty (RSA)

In elderly patients with no symptoms and no discomfort, a conservative treatment approach is often preferable.

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1: with Geyser sign
    Drag here to reorder.
  • Case 2: with Geyser sign
    Drag here to reorder.
  • Case 3
    Drag here to reorder.
  • Case 4
    Drag here to reorder.
  • Case 5
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.