Trunk anatomy in 3D:
nerves

The spinal nerves of the trunk, including the intercostal nerves and the lumbar and sacral plexuses.

The thoracic spinal nerves continue as intercostal nerves, which run in the costal groove with the intercostal vessels and supply the thoracic and abdominal walls. The lumbar plexus (L1–L4) and the sacral plexus (L4–S4) give rise to the nerves of the lower abdominal wall, pelvis and lower limb.