Co1 spinal nerve

Nervus spinalis Co1

NervousNervesPelvisLeft and right

View left in 3D View right in 3D

What it is
The Co1 spinal nerve leaves the spinal canal between the sacral hiatus, below the fifth sacral nerve. 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 joins the small coccygeal plexus.
Function
Carries motor fibres to the muscles of its segment (myotome) and sensation back from its strip of skin (dermatome): a small patch of skin over the coccyx.
Size
About 1 mm thick; the mixed nerve is only ~1 cm long before it divides
Clinical note
The single coccygeal nerve is the last and smallest of the 31 pairs; its dorsal ramus supplies the skin over the tailbone.

Nearby nervous structures Ganglion impar, Pudendal nerve, S1 spinal nerve, S2 spinal nerve, S3 spinal nerve, S4 spinal nerve, S5 spinal nerve, Superior and inferior hypogastric plexuses