Non progressive contraction of Esophagus are:

• Tertiary contractions are simultaneous, non progressive, non peristaltic waves that can occur throughout the esophagus • Tertiary contractions represent uncoordinated contractions of the smooth muscles that are responsible for the ‘Cork Screw’ appearance of esophageal spasm on Barium swallow • Tertiary contractions do not have a physiological function and may be observed in the elderly and in patients with esophageal motility disorders