Normally, when you swallow, your esophagus squeezes in a coordinated wave-like motion. In motility disorders, this movement may be too weak, too strong, or uncoordinated, making it difficult to swallow.

There are Primary Motility Disorders that are due to problems with the nerves or muscles of the esophagus itself, like in Achalasia, Esophageal spasm or Ineffective esophageal motility. Some other conditions can affect the integrity of the esophagus and cause disturbances in the way it works.