Bones - Pelvic Girdle

Question 1

Which bones make up the pelvic girdle?

Answer 1

Two hip bones, sacrum and coccyx.

Question 2

What are the joints of the pelvic girdle?

Answer 2

1) Sacroiliac joint - plane-type synovial joint
2) Sacrococcygeal joint
3) Pubic symphysis - fibrocartilaginous joint

Question 3

Functions of the pelvis?

Answer 3

1) Transfers wight from the upper body to the lower limbs
2) Provides attachment for ligaments and muscles
3) Protect and supports viscera

Question 4

The pelvis can be divided into the greater and lesser pelvis. What are the boundaries of each?

Answer 4

Greater pelvis (false pelvis) - located superior to the pelvic inlet - contains the sigmoid colon and ileum - has little obstetric relevance.

Lesser pelvis (true pelvis) - located inferior to the pelvic inlet. Within the lesser pelvis is the pelvic cavity and pelvic viscera.

Question 5

What are the borders of the pelvic brim?

Other terminology of the pelvic brim?

Answer 5

The border of the pelvic inlet is called the pelvic brim.

Posteriorly - sacral promontory

Laterally - arcuate line of the inner ileum and pectineal line of the superior pubic ramus.

Anteriorly - pubic symphysis

Linea terminalis = arcuate line + pectineal line + sacral promontory

Iliopectineal line = arcuate line + pectineal line

Question 6

What are the boundaries of the pelvic outlet?

Answer 6

Located at the end of the lesser pelvis.

Posteriorly - tip of the coccyx

Laterally - ischial tuberosities

Anteriorly - pubic arch

The angle beneath the pubic arch is known as the sub-pubic angle (greater angle in women).

Question 7

Male vs female pelvis?

Answer 7

Majority of women have a gynaecoid pelvis, as opposed to the male android pelvis.

Gynaecoid pelvis is:

Wider + broader

Lighter

Oval-shaped inlet

Less prominenet ischial spines

Greater sub-pubic angle

Less pronounced sacral promontory

Question 8

Clinical relevance: assessment of bony female pelvis