A 17 year-old football player with prior shoulder dislocation presents to the emergency department reporting shoulder pain after fall. You obtain shoulder x-rays and see the following injury (Image courtesy of Richard Hopkins, MD).
What is your diagnosis? Are there any associated lesions you could expect to find? What is your emergency department management?
This is a bony Bankart lesion. Note the hyperdense fragment just inferior to the glenoid. When a tear of the anterior labrum occurs and takes a bone fragment with it, it is termed a bony Bankart, as seen in Image 1 and Image 4. Bankart lesions (tears of the anterior labrum) have been found in up to 96% of first-time dislocations and in nearly all recurrently unstable shoulders [1, 2]. Bony Bankart lesions have been found in 50% of patients with prior dislocation .
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 .
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 of Hill-Sachs and Bankart lesions was even more likely when large Hill-Sachs lesions were present .
Pearl: Be on the lookout for rotator cuff tears. 35% of patients over 40 years of age have concomitant rotator cuff tears with their shoulder dislocations. This incidence jumps to over 80% when patients with shoulder dislocations are over 60 .
Image 2: Hill-Sachs Lesion. Case courtesy of Dr Benoudina Samir, Radiopaedia.org.
Image 3: Posterior view of Hill-Sachs Lesion in action. Case courtesy of Dr Matt Skalski, Radiopaedia.org.
Place the patient in an immobilized sling and encourage follow-up with orthopedics in 1-2 weeks. This is the same treatment you should offer a patient who had a dislocated shoulder that was reduced in the emergency department. Non-operative or surgical treatment may be recommended to correct joint instability and prevent further injury.
Pearl: If a dislocation is chronic (over several days), it should not be reduced in the ED due to concerns for damage to the axillary vasculature, especially with elderly patients.
Bankart and Hill-Sachs lesions indicate 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.
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