Posterior Dislocation of the Shoulder: The Light-Bulb Sign

Posterior dislocation is a rather rare injury, often misdiagnosed. The current report offers valuable insights regarding the anatomical background of this clinical entity and emphasizes the 'light-bulb sign,' which can be observed in anterior-posterior shoulder X-rays when there is a posterior dislocation. It is crucial for healthcare professionals, including emergency department physicians, radiologists, general practitioners, orthopedic surgeons, and other relevant medical experts, to be well-acquainted with this sign and maintain a heightened awareness when encountering such cases. A 57-year-old male presented to the Emergency Department due to right shoulder pain immediately after an epileptic seizure. His arm was locked in internal rotation, while the initial X-rays, although did not reveal evident malalignment, showed the light-bulb sign. Further imaging with a computer tomography (CT) scan exhibited a large (50%) reverse Hill-Sachs defect. The patient was treated surgically with hemiarthroplasty. The light-bulb sign should be a red flag for physicians who evaluate these patients or these X-rays. The patient's history, such as epileptic seizures and examination, especially the locked arm in internal rotation, are of paramount importance for not misdiagnosing these cases.

Bilateral Simultaneous Asymmetrical Anterior Shoulder Dislocation With a Fracture

In this case report, we present the case of a 19-year-old male who presented to the emergency department with bilateral shoulder pain and significantly decreased range of motion. His X-rays showed a bilateral dislocation of the glenohumeral joints, along with a proximal humeral fracture. Shoulder dislocations were manipulated, while the proximal humeral fracture was conservatively managed. Bilateral simultaneous asymmetric anterior shoulder dislocations are uncommon in such a young age group, especially when associated with a sports injury.