Hypochondral region

The hypochondral region corresponds to the lateral and cranial area of the abdomen, located immediately caudal to the thoracic cage, beneath the last ribs (the costal arches). It represents a transition zone between the thorax and the abdomen.

Anatomically, this region includes the abdominal portion located under the costal arches, the external and internal oblique muscles, the transverse abdominal muscle, as well as the abdominal branches of the intercostal nerves. It overlies organs such as the stomach (particularly the fundus), the liver, the spleen depending on the side, and the cranial pole of the right or left kidney depending on the species.

The morphology and underlying organs of the hypochondral region vary among species: in dogs and cats, the left side is closely associated with the stomach and the spleen; in ruminants, the rumen occupies most of the left region while the liver is shifted to the right; in horses, the stomach remains very cranial and the liver occupies nearly the entire right region; in humans, the right and left hypochondria classically correspond to the regions of the liver, gallbladder, stomach, and spleen.