title: Hamman sign.
authors.affiliation: Emergency Medicine Academic Unit, Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China. cagraham@cuhk.edu.hk
authors.forename: Colin A
authors.initials: CA
authors.lastname: Graham
authors.forename: Yin S
authors.initials: YS
authors.lastname: Ong
mesh_terms: D000293:Adolescent; D002637:Chest Pain / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D006801:Humans; D008478:Mediastinal Emphysema / Q000150:complications / Q000000981:diagnostic imaging*; D011026:Pneumopericardium / Q000150:complications / Q000000981:diagnostic imaging*; D013902:Radiography, Thoracic / Q000379:methods*; D014057:Tomography, X-Ray Computed