anatomy 8.3 pt 2

Which bone fuses with both the ilium and ischium?

Pubis.

What is the ischiopubic ramus?

The fused ischial ramus and inferior pubic ramus.

What is the superior pubic ramus?

The portion of the pubis extending from the anterior margin of the acetabulum.

What is the obturator foramen?

A large opening in the hip bone surrounded by the pubic and ischial rami.

What is the pubic crest?

A roughened ridge on the anterosuperior surface of the superior pubic ramus.

What is the pubic tubercle?

The end of the pubic crest where the inguinal ligament attaches.

What ligament attaches to the pubic tubercle?

Inguinal ligament.

What is the symphysial surface (pubic symphysis)?

The articulation site between the left and right pubic bones.

What is the pectineal line?

A ridge on the medial surface of the pubis that joins the arcuate line.

What is the pelvic brim?

A continuous oval ridge that divides the pelvis into the true and false pelvis.

Which structures form the pelvic brim?

Pubic crest, pectineal line, arcuate line, and the inferior edges of the sacral ala and promontory.

What is the true pelvis?

The portion inferior to the pelvic brim that contains the pelvic organs.

What is another name for the true pelvis?

Lesser pelvis.

What is the false pelvis?

The portion superior to the pelvic brim that contains the lower abdominal organs.

What is another name for the false pelvis?

Greater pelvis.

What encloses the false pelvis?

The alae of the iliac bones.

What is the pelvic inlet?

The superior opening enclosed by the pelvic brim.

What is another name for the pelvic inlet?

Superior pelvic aperture.

Where is the pelvic inlet located?

Between the true and false pelvis.

What is the pelvic outlet?

The inferior opening of the true pelvis.

What is another name for the pelvic outlet?

Inferior pelvic aperture.

What structures bound the pelvic outlet?

Coccyx, ischial tuberosities, and inferior border of the pubic symphysis.

What body region does the pelvic outlet form?

Perineum.

Why is the pelvic outlet clinically important?

It must be wide enough for childbirth.

Which type of pelvis usually has ischial spines projecting into the pelvic outlet?

Male-like pelvis.

Which type of pelvis usually has a wider pelvic outlet?

Female-like pelvis.

What is the most reliable skeletal indicator of genetic sex?

The pelvis.

Why is the female-like pelvis generally wider?

To accommodate pregnancy and childbirth.

How does the female-like ilium differ from the male-like ilium?

It flares more laterally.

How does the male-like ilium differ from the female-like ilium?

It projects more superiorly.

How does the greater sciatic notch differ between the sexes?

Female-like: wide and shallow; Male-like: narrow, deep, and U-shaped.

What is the preauricular sulcus?

A groove between the greater sciatic notch and the sacroiliac joint.

In which pelvis is the preauricular sulcus usually present?

Female-like pelvis.

In which pelvis is the preauricular sulcus usually absent?

Male-like pelvis.

Why is the female-like pelvis considered better adapted for childbirth?

It is wider, shallower, has a larger pelvic outlet, and has fewer inward-projecting bony structures.