<prompt> Sacrotuberous ligament is pierced byPerforating cutaneous nervePosterior femoral cutaneousSuperior gluteal nerveSciatic nerve  <response>: Ans: A Perforating cutaneous nerveSacrotuberous ligament STL -Stabiliser of sacro-iliac joint.Connects bony pelvis to veebral column.Structure piercing STL - Perforating cutaneous nerve.Perforating cutaneous nerve:Cutaneous nerve that arises from the 52 and 53 nerve roots of the sacral plexus.Supplies lower medial pa of buttock. 