Anatomy of the Sacrum and Coccyx

How many pairs of sacral foramina does a sacrum typically have?

4 pairs

This is a large, winglike lateral mass located on each side of the sacral base

Ala

The sacrum is the only bony anatomy considered to be part of the ______ and ________ skeleton

Axial and appendicular

Where is the Sacrum located?

Directly inferior to the lumbar spine and between the 2 innominate bones, forming the posterior aspect of the pelvic cavity

Where is the Coccyx located?

Directly inferior to the sacrum

The sacrum has a wide base with the apex pointed ___________

Downward

The superior articular processes articulate with the inferior articular processes of L5 to form the........

Lumbosacral junction

The posterior surface of the sacrum is rough for what reason?

Muscle attachment

The anterior surface of the sacrum is ________

Relatively smooth

The vertebral foramen of the sacrum forms a descending tunnel called the _________

Sacral canal

What part of the sacrum provides passageways for the sacral nerves through the anterior and posterior sides of the sacrum

Sacral foramina

The superior articulating process on the superior aspect of the coccyx articulate with the inferior segment of the sacrum to form the ________________

Sacrococcygeal articulation

Laterally, the left and right borders of the superior articular processes articulate with the ilium to form the _______

Sacroiliac joints

This is a curved, inverted triangular bone that is formed by the fusion of the 5 sacral vertebral segments

Sacrum

The sacrum is _______ in females than males

Shorter

The coccyx is ________ shaped and consist of _____ vertebrae that fuse into one segment in an adult

Triangular, 3-5