referred pain

Pain arising from a visceral organ (viscus) varies from dull to severe, but is poorly localized. It radiates to the part of the body supplied by somatic sensory fibers associated with the same segment of the spinal cord that receives the visceral sensory (autonomic) fibers from the viscus. The pain is interpreted by the brain as if the irritation occurred in the area of the skin supplied by the dorsal roots of the affected segments. This is called visceral referred pain. 1) stomach - nerve supply: anterior (T6-T9 or T10) - referred site: epigastric & left hypochondriac regions 2) duodenum a) nerve supply: - vagus nerves -presynaptic sympathetic fibers (T5-T9 or T10) - reach celiac & superior mesenteric ganglia via greater splanchnic nerves b) referred site: epigastric region 3) head of pancreas - nerve supply: vagus & thoracic splanchnic nerves (T8-T9) - referred site: inferior epigastric region 4) jejunum & ileum a) nerve supply: - posterior vagal trunks - presynaptic sympathetic fibers (T5-T9) - reach celiac ganglion via greater splanchnic nerves b) referred site: periumbilical region (intestinal obstruction) 5) colon a) nerve supply: - vagus nerves - presynaptic sympathetic fibers (T10-T12 <proximal>) - reach celiac & superior & inferior mesenteric ganglia via greater splanchnic nerves - parasympathetic supply to distal colon is derived from pelvic splanchnic nerves: (L1-L3 <distal>) - hypogastric nerves - inferior hypogastric plexus b) referred site: - hypogastric region <proximal colon> - left lower quadrant <sigmoiditis> 6) spleen - nerve supply: celiac plexus (T6-T8) - esp. greater splanchnic nerve - referred site: left hypochondriac region 7) appendix a) nerve supply: - sympathetic & parasympathetic fibers from the superior mesenteric plexus (T10) - afferent nerve fibers accompany sympathetic nerves to T10 segment of spinal cord b) referred site: - periumbilical region (early) - right lower quadrant (late) 8) gallbladder & liver a) nerve supply: - celiac plexus (sympathetic) - vagus nerve (parasympathetic) - right phrenic nerve (sensory) - T6-T9 b) referred site: - epigastric region (early) - right hypochondriac region (later) - posterior thoracic wall - right shoulder (diaphragmatic irritation) 9) kidneys & ureters a) nerve supply: - nerves arise from renal plexus - sympathetic, parasympathetic & visceral afferent fibers from thoracic & lumbar splanchnics & the vagus nerve - T11-T12 b) referred site: - small of back, flank (lumbar quadrant) - extending to groin (inguinal region) & genitals

References

Grant's Atlas of Anatomy, 10th edition, AMR Agur & MJ Lee (eds), Lippincott Williams & Wilkins, Philadelphia, 1999