Lumbar Splanchnic Nerves

nervi splanchnici lumbales

The lumbar splanchnic nerves are four branches from the lumbar sympathetic ganglia (L1-L4) that pass medially to join the inferior mesenteric, renal, and aortic autonomic plexuses. They carry preganglionic sympathetic fibres to the visceral ganglia of the pelvic plexuses and visceral afferents from the pelvic and lower abdominal organs. The upper lumbar splanchnic nerves contribute to the superior hypogastric plexus, connecting them to pelvic autonomic supply.

Region: Abdomen

Clinical Relevance

Clinical Notes

The lumbar splanchnic nerves form the sympathetic outflow through the lumbar chain to the abdominal and pelvic plexuses, complementing the thoracic splanchnic supply to the upper abdomen. They are disrupted during retroperitoneal lymph node dissection and para-aortic dissection in oncological surgery. Their damage causes vasodilatory effects in the lower limbs from sympathetic denervation, producing warmth and increased perfusion on the operated side. In chronic pelvic pain, lumbar sympathetic block targeting the chain ganglia modulates the transmission of visceral pain signals through the lumbar splanchnic pathways.

Pathology

Common Injuries & Conditions

Lumbar Splanchnic Disruption in RPLND

Retroperitoneal lymph node dissection for testicular cancer disrupts the lumbar splanchnic nerves as they emerge from the sympathetic chain, contributing to the retrograde ejaculation and vasomotor changes seen after bilateral template dissection; nerve-sparing techniques preserve these fibres to reduce autonomic morbidity.