hiatus hernia (HH)

Last edited 02/2018 and last reviewed 06/2021

Hiatus hernia is the herniation of an abdominal organ into the thoracic cavity, usually the stomach, through a widening of the oesophageal hiatus in the diaphragm.

Two main types are recognised:

  • sliding or axial hiatus hernia – 85-95% of hiatus hernias - this is a direct herniation through the oesophageal hiatus
  • paraoesophageal or rolling hiatus hernia – 5-15% - the herniation occurs due to the abdominal organ pushing up beside the oesophagus

Depending on the subdivision of para-esophageal hiatal hernias, a more comprehensive classification has been proposed which divides hiatus hernia into four types:

  • type I    - sliding hiatal hernia
  • type II  - classic form of para-oesophageal hernia
  • type III - mixture of type I and II hiatal hernia
  • type IV - herniation of abdominal structures other than the stomach (spleen, colon, pancreas, etc.) (2)

Type II-IV belongs to the para oesophageal hernia group with type III being the most common (more than 90%) and type II the least common (2).
Rarely patients may present with a giant hiatal hernia, defined by a hernia that includes at least 30% of the stomach in the thorax.

  • majority are type III hernia with a sliding and paraesophageal component
  • a third of giant paraesophageal hernias are associated scoliosis (1,3).

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