For a long time we have known that in thoracic affections such as pneumonia and pleurisy, pain may be reflected from the chest to the abdomen, thereby simulating abdominal disease. (Andral, 1836; Watson, 1871; Fagge and others.) In discussions of this not infrequent occurrence, attention has been directed chiefly to the pain alone, and it has been stated that such abdominal reference of pain of thoracic origin may be differentiated directly by the absence, in thoracic disease, of abdominal tenderness and other intrinsically abdominal findings.
The object of this paper is to establish clearly the existence of deep abdominal tenderness, muscular rigidity, collapse and the Hippocratic abdominal symptoms of rupture and peritonitis in purely thoracic affections.
—Case of right lower lobe pneumonia, in which abdominal pain, tenderness, rigidity and retraction, in association with collapse, precisely simulated perforative peritonitis; in which operation disclosed no abdominal abnormality, and
EDWARDS AR. ABDOMINAL PAIN AND TENDERNESS, MUSCULAR RIGIDITY AND PSEUDOPERFORATIVE OR PSEUDOPERITONITIC SYMPTOMS IN THORACIC DISEASE— PNEUMONIA AND PERICARDITIS. JAMA. 1911;LVI(24):1784–1785. doi:10.1001/jama.1911.02560240014004