Ruptured pseudoaneurysm of the thoracoacromial artery associated with habitual shoulder dislocation: a case report

Background: Shoulder dislocation is one of the most common joint dislocations encountered in emergency departments, but vascular complications are rare and often underrecognized. Pseudoaneurysms of the thoracoacromial artery, a branch of the axillary artery, are extremely uncommon and may present with subtle symptoms, delaying diagnosis. Case Presentation: An 82-year-old woman with a history of habitual anterior shoulder dislocation presented with a 10-day history of progressive pain and swelling in the left shoulder. She was on edoxaban for atrial fibrillation. Examination revealed localized tenderness and swelling without neurological deficits. Contrast-enhanced computed tomography showed a 30 × 35 × 35 mm pseudoaneurysm arising from the acromial branch of the thoracoacromial artery. Angiography confirmed contrast extravasation. Endovascular embolization was performed using a proximal Celeskue sheet placement followed by injection of N-butyl cyanoacrylate and Lipiodol. The procedure achieved complete exclusion of the lesion. At three-month follow-up, the patient remained asymptomatic with preserved left upper limb function. Conclusion: Although rare, pseudoaneurysms of the thoracoacromial artery can occur after repeated shoulder dislocation and reduction, especially in elderly patients on anticoagulation therapy. Early recognition through imaging and prompt endovascular intervention can prevent serious vascular and neurological complications.