30- Anatomy of the Pelvis

Question 1

Define Pelvic Diaphragm

Answer 1

Partition between the pelvic cavity and the

perineum.

Question 2

What muscles make up the pelvic diaphragm?

Answer 2

Levator ani

Coccygeus

Question 3

What provides support for pelvic organs?

Answer 3

Condensation of the pelvic diaphragm that form ligaments surrounding the following structure:
Neck of uterus
Cervix of Uterus

Question 4

Are there any openings in the pelvic diaphragm?

Answer 4

Yes, 2 midline apertures in males and 3 in females [urethra, vagina, and rectum]

Question 5

Which part of the pelvic diaphragm is covered by pelvic fascia?

Answer 5

Upper surface

Question 6

what muscles compose the Levator ani muscle?

Answer 6

3 paired muscles [M → L]
Puborectalis
Pubococcygeus
Iliococcygeus

Question 7

What is the nerve supply of Levator ani muscle?

Answer 7

4th sacral nerve

Perineal branch of pudendal nerve [S2-S4]

Question 8

Define Anatomical conjugate

Answer 8

Distance between the upper margin of the pubic symphysis to promontory and is about 12-cm.

Question 9

Define Obstetrical conjugate

Answer 9

Distance between the posterior surface of the symphysis to promontory

Question 10

What is the length of Obstetrical conjugate [OC]?

Answer 10

11.5-cm.

Question 11

Define Diagonal conjugate

Answer 11

Distance between the inferior pubic ligament to promontory

Question 12

What is the length of Diagonal Conjugate?

Answer 12

13-cm

Question 13

Which Anterioposterior measurement can be measured by digital examination in females?

Answer 13

diagonal Conjugate

Question 14

What is the length of the Pelvic outlet in females?

Answer 14

12.5 cm

Question 15

What is the length of transverse diameter of pelvic inlet?

Answer 15

13.5 cm

Question 16

What is the sacral promontory?

Answer 16

Most superior surface on the body of the first sacral vertebrae

Question 17

What are the boundaries of the Pelvic outlet?

Answer 17

Anterior:
Lower margin of pubic symphysis with arcuate pubic ligament 
Posterior:
tip of coccyx
Laterally:
Conjoint ischiopubic rami [AL]
Ischial Tuberosity [L]
Sacrotuberous Ligaments [PL]

Question 18

What are the anterioposterior and transverse diameters of the pelvic outlet?

Answer 18

AP diameter: 12.5

Transverse diameter: 10 cm

Question 19

What measurements of the pelvis may cause difficulties during deliveries?

Answer 19

OC < 10 cm

Transverse diameter < 8.5 cm

Question 20

What are the four type of Females Pelvises?

Answer 20

Gynecoid
Android
Anthropoid
Platypelloid

Question 21

Which female pelvis is most suitable for normal vaginal delivery?

Answer 21

Gynecoid

Question 22

Describe Gynecoid pelvis

Answer 22

Circular inlet

Question 23

Describe Android pelvis

Answer 23

Triangular inlet 
Prominent ischial spine 
More angulated Pubic arch [< 90°]
Heart shaped pelvis 
resembles male pelvis

Question 24

Describe Anthropoid pelvis

Answer 24

AP diameter is longer than transverse diameter

Question 25

Descrive Platypelloid Pelvis

Answer 25

Flat pelvis with kidney shaped brim AP diameter is reduced Transverse diameter is increased

Question 26

What condition causes Platypelloid pelvis?

Answer 26

Vitamin D deficiency [osteomalacia]

Question 27

List the type of female pelvises and if each are suitable for normal vaginal delivery

Answer 27

Gynecoid → best chance for normal delivery Android → least suitable for normal delivery Anthropoid → Difficulty in delivery Platypelloid → normal delivery not possible

Question 28

What is the function of the Puborectalis?

Answer 28

maintains forward angulation between rectum and anal canal | Maintains fecal continence