Pelvic Anatomy

Question 1

Name the fxns of the pelvis.

Answer 1

• upper body support
• external genitalia attachment
• passage of childbirth
• protection of pelvic organs, blood and nerve supplies, their venous and lymphatic drainage
• transfer of the weight to 2 femurs from vertbral colum

Question 2

What does the bony pelvis consist of?

Answer 2

2 Hip bones
SACRUM
COCCYX (NOT part of pelvic girdle)

Question 3

What is the hip bone made of?

Answer 3

(iluim-superiorly, ischium and pubis)

• -fuses at AGE 4-8 at the ACETABULUM (triradiate)
• —pubis fuses later at 17 for females

Question 4

The big tubercle of the the ischium

—what you sit on

Answer 4

ichial tuberosity

Question 5

What the superior opening of the pelvis?

Answer 5

pelvic inlet

Question 6

What are the boundaries of the pelvic inlet?

Answer 6

• sacral promontory (prominent sacral bit)
• ilium
• superior pubic ramus
• pubic symphysis

Question 7

What are the boundaries of the pelvic outlet?

Answer 7

• pubic symphysis
• ischiopubic ramus
• ischial tubersosity
• sacrotuberous ligament
• coccyx

Question 8

Where is the pelvic cavity?

Answer 8

• between the pelvic INLET and the PELVIC floor

Question 9

What is the greater/false pelvis?

Answer 9

• larger area above the true pelvis

Question 10

What does the pelvic floor seperate the pelvic cavity from?

Answer 10

the perineum

Question 11

What is the palpable parts of the pelvis?

Answer 11

• iliac crest
• pointy bit -ASIS
• PUBIC symphysis
• ischial spines are papable on vaginal examination at 4 and 8 o’clock position (important in PV birth)
• ischial tuberosity
• coccyx a the start of the gluteal cleft

Question 12

Name the synovial joints of the hip.

Answer 12

• hip joint

- sacroiliac joint (only anterior aspect—posterior is fibrous)

Question 13

Name a secondary cartilaginous joint.

Answer 13

Pubic symphysis …minimal flexibility

Question 14

Name 2 important ligament in the pelvic region.

Answer 14

sacrotuberous (ichial tuberosity)

sacrospinous (ischial tuberosity)

Question 15

What formaninae do the ligaments form and what is the purporse?

Answer 15

– they form the greater and lesser sciatic foraminae ——-important passage ways for nerves and vessels

Question 16

What covers the obturator formamen?

Answer 16

• obturator membrane

- fully covered except a little superior bit —-OBTURATOR canal —passing of obturator NERVE and vessels

Question 17

What covers the obturator formamen?

Answer 17

• obturator membrane

- fully covered except a little superior bit —-OBTURATOR canal —passing of obturator NERVE and vessels

Question 18

What life threatening consequence may arise from fracture of the bony pelvis?

Answer 18

• hemorrhage of common iliac artery and vein!!!
• OTHERS: damage to sacral plexus
• damage to pelvic organs

Question 19

What is the diff. between a male and female pelvis?

Answer 19

• AP and transverse diameters of the female pelvis is LARGER in the female at both INLET and OUTLET
• subpubic ARCH and angle is bigger in female
• much shallow pelvic cavity in the female

Question 20

What are the soft spots of the baby skull?

Answer 20

• anterior and posterior FONTANELLE

- anterior closes in 18 months-2 years

Question 21

What is meant by moulding of the baby skull ?

Answer 21

• the movement of one bone over another to allow the fetal head to pass through the pelvis

Question 22

What is the vertex of the baby’s skull?

Answer 22

• diamond shape between the 2 PARIETAL eminences
  and the A and P fontanelle
• important to palpate the bby’s skull to know the orientation of the bby’s skull

Question 23

What is the importance of the occipitofrontal diameter of the baby’s skull?

Answer 23

• the occipitofrontal diameter is LONGER than the biparietal diameter
• should therefore lie in line with the transverse diamter—-easier for it to leave the cavity

Question 24

WHy does the baby’s head have to turn towards the end of the labor?

Answer 24

• –in order to leave in an OA (occipitoanterior position) because the AP becomes the longest bit
• bby’s neck should be flexed and then extended

Question 25

When does the third rotation occur in labour?

Answer 25

• once the baby’s head is delivered

- to allow the delivery of the shoulders and then the rest of the body

Question 26

What is referred to as the station baby during delivery?

Answer 26

• distance of the fetal head from the ischial spine

- a negative number means the head is SUPERIOR to the ischial spine

Question 27

Describe the change in the orientation of the foetal head throughout child birth.

Answer 27

1. At pelvic inlet: fetal head should be TRANSVERSE
2. As it descends through the pelvic cavity, foetal head should ROTATE and should be flexed.
3. A the pelvic OUTLET= fetal head should lie in OA and extension of the head should occur.