It is of small size, and arises from the ventral divisions of the third and fourth lumbar nerves.

It descends along the medial border of the psoas major, crosses the superior ramus of the pubis, and passes under the pectineus, where it divides into numerous branches.

One of these supplies the pectineus, penetrating its deep surface, another is distributed to the hip-joint; while a third communicates with the anterior branch of the obturator nerve.

Occasionally the accessory obturator nerve is very small and is lost in the capsule of the hip-joint.

This article incorporates text in the public domain from page 955 of the 20th edition of Gray's Anatomy (1918)