Primary oesophageal motility disorders: how primary are they?

The normal regulation of oesophageal peristalsis is complex. Nitric oxide-containing inhibitory neurons and cholinergic excitatory nerve fibres play the key roles. In the so-called primary oesophageal motility disorders, the coordination of oesophageal contractions and lower oesophageal sphincter function is disturbed (achalasia, diffuse oesophageal spasm), or the amplitudes of peristaltic contractions are abnormally high (nutcracker oesophagus). This article focuses on the pathophysiology of achalasia and nutcracker oesophagus. There is evidence that achalasia and nutcracker oesophagus should not be considered parts of one and the same range of diseases.