Anatomy of Lumbar splanchnic nerve

Lumbar splanchnic nerve

It is the peripheral nerves of sympathetic nervous system

Location of preganglionic neuron : Its pre-ganglionic neurons are located in the  lateral horn of gray matter of Lumbar 1,2 spinal cord segment

Sympathetic ganglion : Its preganglionic fibres do not synapse with corresponding sympathetic ganglion . these fibres only pass through sympathetic ganglion 1,2.

Collateral ganglion : The pre-ganglionic sympathetic fiber of lumbar splanchnic nerve synapse with post ganglionic neuron located in the Inferior mesenteric ganglion

Nerve fibers convey by  lumbar splanchnic nerves : they convey two types of fibres

1.      they convey pre-ganglionic sympathetic fibres also known as general visceral efferent fibers which innervate smooth muscle cells

2.       They also convey general visceral afferent fibers which collect sensory information from  pelvic viscera and passage through the

·          inferior mesenteric ganglion,

·         sacral splanchnic nerve then

·         sympathetic and dorsal root ganglion

Plexus : they take part in the formation of inferior mesenteric plexus which is situated near the inferior mesenteric artery

They also form superior hypogastric plexus which situated near the bifurcation of abdominal

Function: Innervate pelvic viscera and vasculature