The lateral branches of the second sacral dorsal rami emerge with the medial branches deep to multifidus.  They join with the lateral branches of the dorsal rami of L5, S1 and S3 to form loops on the dorsum of the sacrum.  From here branches arise, which pierce multifidus and the aponeurosis of erector spinae to run posterior to the sacrotuberous ligaments, to form a second series of loops under gluteus maximus.  Gluteal branches pierce gluteus maximus to terminate in the overlying skin.

Supply
The lateral branches of the second sacral dorsal spinal rami supply skin over the sacrum and medial gluteal regions.