Hamman's sign is seen with:

Ans. d (Esophageal perforation). (Ref. Harrison's medicine 16th ed. 1569)Hamman's sign (Laennec-Hamman symptom, Laennec-Miiller-von Bergmann, Hamman's crunch)# A crunching, rasping sound, synchronous with heartbeat, heard over the precordium and sometimes at a distance from the chest in spontaneous mediastinal emphysema.# Hamman's sign may be present in acute mediastinitis, for e.g. as in esophageal perforation. It is a crunching sound that is heard over the anterior chest in synchrony with cardiac systole.