The Esophagogastric Junction

Abstract
The lower esophageal sphincter regulates the flow of food between the esophagus and the stomach. It is now clear that both the intrinsic smooth muscle of the distal esophagus and the skeletal muscle of the crural diaphragm constitute the sphincter mechanism at the lower end of the esophagus.1 Furthermore, in normal subjects and patients with reflux esophagitis, transient relaxation of both sphincters rather than diminished lower esophageal sphincter pressure is the major mechanism of gastroesophageal reflux.2 In this article we review the current understanding of the physiology of the sphincter mechanism at the esophagogastric junction and its relation to esophageal . . .