Through the greater sciatic foramen

This foramen is surrounded by the following structures:
Sacrospinous ligament :Connects the sacrum and coccyx to the ischial spine
Sacrotuberous ligament:Connects the inferior posterior iliac spine, the inferior lateral border of the sacrum, and the coccyx to the ischial tuberosity
Greater sciatic notch
The piriformis muscle passes through here. The piriformis muscle divides the notch into the suprapiriform foramen and the infrapiriform foramen.
The superior gluteal artery, vein, and nerve pass through the suprapiriform foramen.
The sciatic nerve; inferior gluteal artery, vein, and nerve; internal pudendal artery and vein; pudendal nerve; and posterior cutaneous nerve of the thigh pass through the infrapisiform foramen.