Unraveling functional abdominal bloating and distension: the role of thoraco-abdominal accommodation and a physical sign to aid its detection

Bloating and distension are common complaints in patients with irritable bowel syndrome of which the cause has remained elusive, although it has been shown that the obvious explanation of excessive gas is unlikely. The recent application of technologies such as the gas challenge technique, abdominal inductance plethysmography, CT scanning, as well as electromyography of the diaphragm and anterior abdominal wall, have allowed the situation to be slowly unraveled. It is now seems probable that the pathophysiology of bloating and distension are subtly different with the former having a sensory component whereas mechanical factors, such as disordered abdominal accommodation, contribute more to the latter.