An Unusual Case of Chest Pain in a 16-Year-Old Male.

Hamman sign is a rare clinical finding characterized by a crunching or clicking sound synchronous with the cardiac cycle, typically heard over the precordium. It is most commonly associated with pneumomediastinum or, less frequently, pneumothorax. Although often subtle and transient, its presence can provide an important early clue to underlying thoracic air leakage, especially in young patients without a history of trauma. This case illustrates how timely identification of Hamman sign, followed by appropriate diagnostic imaging-most notably chest radiography or computed tomography-is vital for recognizing this clinical finding and guiding effective management. In addition, increased clinician awareness can facilitate earlier intervention and reduce the risk of complications.