Posterior bony humeral avulsion of glenohumeral ligament with reverse bony Bankart lesion.

Recurrent, posterior glenohumeral joint instability is uncommon. Posterior capsulolabral abnormalities, although well described in the literature, are less common than their anterior counterparts and make up roughly 2-5% of all shoulder instability. Previous authors have reported cases of posterior humeral avulsion of the glenohumeral ligament (PHAGL) and a combined posterior Bankart lesion and PHAGL associated with posterior instability. To our knowledge, there has been no reported case of a combined reverse bony Bankart and a posterior bony HAGL injury. We present a case of traumatic posterior instability as a result of a combined posterior bony humeral avulsion of the glenohumeral ligament (PBHAGL) and a posterior bony Bankart lesion.