The Shoulder

Aseptic Necrosis

The main cause is traumatic (as a complication of an intra-articular fracture).
Risk factors include long-term corticosteroid use, smoking, and alcohol consumption
Sometimes after a trivial trauma.
In divers

Besides a capsular pattern, the clinical examination shows crepitus and a hard endfeel.

Radiology

glenohumeral joint space is preserved. The vertically-oriented sliver of bone medial to the humeral head is the subchondral bone of the humeral head which has died and has loosened from the remaining deeper layers of bone. Note the loss of the normally rounded contour of the medial aspect of the humeral head.

Treatment:

Intra Articular Injections if there are signs and symptoms of capsular irritation.