Presentation
? Rotator cuff injury. Pt presented to emergency last evening with normal shoulder XR following a fall
Patient Data
Age: 50 years
Gender: Female
From the case:
Acute posterior shoulder dislocation (ultrasound)

- the humeral head is posteriorly centered relative to the glenoid in keeping with a posterior dislocation
- glenohumeral joint effusion with fluid tracking along the long head of biceps tendon sheath
- the rotator cuff tendons are generally heterogenous and are difficult to assess in the setting of suspected glenohumeral joint dislocation
From the case:
Acute posterior shoulder dislocation (ultrasound)
Loading images...

Frontal

- posteriorly translated humeral head relative to the glenoid in keeping with a posterior dislocation
From the case:
Acute posterior shoulder dislocation (ultrasound)
Loading images...

Sagittal post relocation

- the glenohumeral joint has been relocated
- focal depression of the anterior humeral head in keeping with a reverse Hill-Sachs lesion
- no osseous defect / Bankart injury to the posterior glenoid
Case Discussion
Posterior shoulder dislocation is not commonly diagnosed on ultrasound as is usually easily seen on x-ray.
This patient presented to our outpatient ultrasound department having had an x-ray at another institution, which was reported as normal.
She then went to have confirmatory x-rays at our institution as well as a subsequent post-reduction CT, which showed the reverse Hill-Sachs defect.