T12 spinal nerve

Nervus spinalis T12

NervousNervesThoraxLeft and right

View left in 3D View right in 3D

What it is
The T12 spinal nerve leaves the spinal canal between T12 and L1. Its sensory (dorsal) and motor (ventral) roots meet just beyond the dorsal root ganglion; the short mixed nerve then splits into a small dorsal ramus for the back muscles and skin and a larger ventral ramus, which becomes the subcostal nerve.
Function
Carries motor fibres to the muscles of its segment (myotome) and sensation back from its strip of skin (dermatome): the lower abdomen and the skin above the pubis and the hip.
Size
About 2-3 mm thick; the mixed nerve is only ~1 cm long before it divides
Clinical note
Its ventral ramus runs under the twelfth rib as the subcostal nerve, which can be irritated in kidney surgery through the flank.

Nearby nervous structures 6th intercostal nerve, 7th intercostal nerve, 8th intercostal nerve, T10 spinal nerve, T11 spinal nerve, T6 dorsal root ganglion, T6 spinal nerve, T7 spinal nerve, T8 spinal nerve, T9 spinal nerve