Sacrum

A. Auricular surface (sacroiliac joint)

Ala

Anterior

Apex

B. Superior articular process

Base (body)

Body (1st segment)

D. Sacral horn (cornu) Horn (cornu) of coccyx

E. Sacral canal (between superior articular processes)

Median sacral crest

Pelvic (anterior) sacral foramina

Posterior

Promontory

Sacral promontory

Superior articular process

Соссух