Abstract
Disorder of motor function of the esophagus usually is manifested by one or more of four physiologically detectable changes: achalasia, motor failure or paralysis, dyskinesia, and spasm or cramp. Achalasia is seen in the gastroesophageal sphincter. Partial or complete failure of contraction occurs most commonly in the esophagus. In dyskinesia, the progressive sequence of the contraction is lost, and the entire organ or a part of it contracts simultaneously. Too much contraction for too long a period causes diffuse spasm. Refinements in technics of detection should result in better definition of esophageal motor disorders and better management of patients.