postsacral
/ˈpɒst.sæk.rəl/Definitions
1. adjective
relating to or situated at the back of the sacrum, a triangular bone at the base of the spine.
“The postsacral vertebrae are a crucial part of the spine’s structure.”
2. noun
the region or area at the back of the sacrum.
“The doctors carefully examined the patient’s postsacral area for any injuries.”