Answer: At the brim of the pelvis, the promontory of the sacrum unite with the iliopectineal lines of the innominate bones of the hip to form the brim of pelvis.
Step-by-step explanation:
The pelvic girdle is formed from two innominate ( hip) bones. The pelvis is the term given to the basin - shaped structure formed by the pelvic girdle and it's associated sacrum.
Each hip bone consists of three fused bones which includes:
--> ilium: this forms the upper flattened part of the hip bone
--> Pubis: this forms the anterior part of the hip bone and
--> Ischium: This forms the inferior and posterior part of the hip bone.
The pelvis rim forms the outer bony edges of the pelvic inlet which is the boundary between the greater pelvis and lesser pelvis. The borders that forms the pelvis rim includes:
--> promontory of the sacrum located at the posterior of the rim
--> iliopectineal lines which forms the lateral border and
--> the public symphysis which is at the anterior of the pelvis rim.