Bony deformity and oedema pattern consistent with CT-demonstrated reverse Hill-Sachs injury.
Large volume joint effusion and oedema in surrounding musculature, particularly the posterior deltoid, lateral subscapularis and infraspinatus.
The inferior glenohumeral ligament remains attached at the humeral aspect, however there is some buckling and ill-defined increased signal at the posterior glenoid attachment, consistent with local injury, likely a stripping injury with small full-thickness defect. The remainder of the glenoid attachment is intact.
The labrum is intact, in particular, no reverse bony or cartilaginous Bankart lesion. The bicipital anchor is unremarkable and there is no evidence of SLAP injury.
Mild thickening of subacromial subdeltoid bursa, without a large fluid collection. Associated minor bursal surface irregularity and increased signal of the supraspinatus tendon, consistent with grade 1 fraying, likely non-acute. No discrete or acute tear of the rotator cuff.
Mild degenerative changes are present within the acromioclavicular joint, however this remains normally aligned with no evidence of acute injury.
Although there is oedema in the region of the rotator interval, the superior glenohumeral and coracohumeral ligaments remain intact and the overall extent of oedema in this region is similar to that elsewhere around the shoulder joint.
Conclusion
Reverse Hill-Sachs fracture and injury to the posterior aspect glenoid attachment IGHL, consistent with previous posterior dislocation. No posterior labral injury, SLAP lesion or acute rotator cuff tear.