The pre sacral space is inside the pelvis,behind the rectum and in front of the coccyx and sacrum.

• The 2 upper lateral points correspond to postero superior iliac spines ( in green)
• The inferior point of the pre sacral triangle corresponds to the apex of the sacral triangle  (in red)

On the upper part of the inter gluteal cleft,at the intersection between the superficial cleft and the deep cleft .

Use the 5 th finger to find by palpation the bony inferior point of the pre sacral triangle .