We describe a case of a false aneurysm of the common carotid artery, caused by spontaneous carotid rupture, with atypical clinical presentation. The patient came to the our Hospital complaining of left shoulder pain and functional impairment of her left arm, during the past 20 days. The diagnostic work-up, color Doppler ultrasound, MR and angiography, evidenced a cervical false aneurysm; the electromyography showed denervation of the deltoid muscle, caused by cervical nerve roots compression. The therapeutic stages were initially an endovascular stent placement; then a surgical stage with evacuation for the hematoma and reconstruction of the carotid artery with saphenous graft.