Presentation
Epileptic. Seizure and shoulder pain.
Patient Data
Age: 20 years
From the case:
Posterior glenohumeral joint dislocation
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'Lightbulb' sign of the humeral head, with the axillary view confirming a posterior glenohumeral joint dislocation with an engaging reverse Hill-Sachs defect. An entonox device overlies the chest.
Case Discussion
The lightbulb sign occurs when the humeral head is posteriorly dislocated causing humeral head internal rotation giving this appearance. A second view should be used to confirm these findings, or CT when positioning can be difficult due to pain and/or associated fracture.