What is your diagnosis? What injury does this represent?

Bony Bankart lesion. Note the hyperdense fragment just inferior to the glenoid. 

• Pearl: A Bankart lesion involves an injury to the anterior labrum. If a tear occurs and takes a bone fragment with it, it is termed a bony Bankart (see Images 1 and 4).
• Pearl: Bankart lesions have been found in up to 96% of first-time dislocations [1] and in nearly all recurrently unstable shoulders [2], while bony Bankart lesions have been found in 50% of patients with prior dislocation [3].

What additional lesion can also be seen in these injuries?

A Hill-Sachs lesion (see Image 2). Hill-Sachs lesions are compression fractures caused by the soft postero-lateral humeral head forcefully striking the bony anterior glenoid rim as the head tries to reenter the socket immediately following dislocation (see Image 3). These lesions have been reported in up to 90% of first-time dislocations, and can be seen on MRI in nearly all patients with recurrent instability [5].

• Pearl: If either a Bankart or Hill-Sachs deformity is seen, the patient is 11 times more likely to have suffered the associated injury as well, so be on the lookout (see Image 4). Co-occurrence was even more likely when large Hill–Sachs lesions were present [4].
  
  
• Pearl: Also watch for rotator cuff tears. Their incidence has been reported in 35% of patients over 40 years of age and greater than 80% of those over 60 [6].

Image 2. Case (and arrows) courtesy of Dr Benoudina Samir, Radiopaedia.org, rID: 58016

Image 3: Posterior view of Hill-Sachs Lesion in action. Case courtesy of Dr Matt Skalski, Radiopaedia.org, rID: 65796

What is your management and disposition from the ED?

Place the patient in an immobilized sling and encourage follow-up with orthopedics in 1-2 weeks. Non-operative or surgical treatment may be recommended to correct joint instability and prevent further injury.

• Pearl: If a dislocation is chronic and has been out for a few days to weeks, it should NOT be reduced in the ED due to concerns for damage to the axillary vasculature, especially with elderly patients.

Why is this important in the ED?

Bankart and Hill-Sachs lesions allude to potential glenohumeral instability. Keep this in mind even with patients who present without dislocation. Recurrent dislocations or feelings of instability with daily activity merit sports medicine or orthopedic follow-up. 

Image 4: Bony Bankart with concurrent Hill-Sachs Lesion. Case courtesy of Dr. Maulik S Patel, Radiopaedia.org, rID: 10089