Viscus

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In anatomy, a viscus (IPA: /ˈvɪskəs/) (plural: viscera /ˈvɪsərə/) is an internal organ of an animal (including humans), in particular an internal organ of the thorax or abdomen. The viscera, when removed from a butchered animal, are known collectively as offal. Internal organs are also known as "innards", or less formally, "guts" (which may also refer to the gastrointestinal tract).

The adjective visceral is used for anything pertaining to the internal organs. Historically, viscera of animals were examined by Roman pagan priests like the haruspices or the augurs in order to divine the future by their shape, dimensions or other factors.

Contents

[edit] Human viscera

Further information: Organs of the human body by region

[edit] Abdomen

[edit] Pelvis and perineum

[edit] Innervation

Autonomic nervous system, showing splanchnic nerves in middle, and the vagus nerve as "X" in blue. The heart and organs below in list to right are regarded as viscera.
Autonomic nervous system, showing splanchnic nerves in middle, and the vagus nerve as "X" in blue. The heart and organs below in list to right are regarded as viscera.

The viscera are mainly innervated parasympathetically by the vagus nerve and sympathetically by the splanchnic nerves. The sensory part of the latter reaches the spinal column at certain spinal segments. Pain in any viscera is perceived as referred pain, more specifically pain from the dermatome (anatomy) corresponding to the spinal segment.[1]

Viscus Nerves [2] Origo in spinal column[2]
stomach T6, T7, T8, T9 and, sometimes, T10
Duodenum T5, T6, T7, T8, T9 and, sometimes, T10
pancreatic head T8, T9
jejunum and ileum T5, T6, T7, T8, T9
colon
Spleen T6, T7, T8
vermiform appendix T10
gallbladder and liver T6, T7, T8, T9
kidneys and ureters T11, T12

[edit] References

  1. ^ Essential Clinical Anatomy. K.L. Moore & A.M. Agur. Lippincott, 2 ed. 2002. Page 199
  2. ^ a b Unless else specified in boxes, then ref is: Essential Clinical Anatomy. K.L. Moore & A.M. Agur. Lippincott, 2 ed. 2002. Page 199

[edit] See also