Migration of wires or pins around the shoulder is a known complication, though their migration within the chest is uncommon. We report an unusual case of hydropneumothorax due to migration of a bent Kirschner wire from the right proximal humerus in a 63 year-old man. We reviewed his clinical history, physical examination, imaging findings, surgical method and outcome. We also reviewed the literature on orthopaedic wire migration and latest technique in removal of the wires. Chest radiographs and chest computerized tomography are useful in detection and diagnosis of this disorder. Regular radiographic follow-up is needed for patients with internal fixation devices; any fractured or migrated pins or wires must be removed immediately to prevent dangerous complications. It is always important to remove the wires at the end of the treatment. Early removal of fixation wires and regular follow-up if wires are retained are essential to prevent serious complications.