Lec1 - Defining the Pelvic Region

Question 1

How many bones (including ligaments) make up the pelvis?

Answer 1

Four:
Ilium
Ischium and pubis
Sacrum
Coccyx

Question 2

What is the latin for pelvis?

Answer 2

Os coxa

Question 3

Name the four ligaments of the pelvis

Answer 3

Sacroiliac - between the sacrum and ilium (with anterior and posterior component)
Sacrococcygeal - sacrum to coccyx
Sacrospinous - sacrum/coccyx to ischial spine
Sacrotuberous - posterior to the sacrospinous, between the lateral aspect of the sacrum margin of the ischial tuberosity

Question 4

What is the perineum?

Answer 4

Refers to the space located at the pelvic outlet and inferior to the pelvic diaphragm - i.e. muscle of the pelvic floor

Question 5

Describe the borders/limits of the perineum

Answer 5

Diamond shaped surface extending from the mons pubis (in females) to the medial surface of the thighs (laterally) and posteriorly to the gluteal folds

Question 6

What are the names of the two triangles that the perineum can be divided into and what is the line of division?

Answer 6

A transverse line from the two ischial tuberosities splits the perineum into 2 triangles:
Urogenital triangle
Anal triangle

Question 7

What does the midpoint of the transverse line joining the two ischial tuberosities define?

Answer 7

The perineal body

Question 8

What is the significance of the perineal body?

Answer 8

The perineal body sees the convergence of several sphincter and perineal pouch muscles
This area can also get damaged during childbirth

Question 9

What does the deep perineal pouch enclose?

Answer 9

Urethra
Vagina in females
Glands e.g. bulbourethral (Cowper glands in males)
Perineal muscles that act as sphincters - Compressor urethrae or urethrovaginal sphincter in females

Question 10

What does the superficial perineal pouch enclose?

Answer 10

Urethra
Vagina in females 
Root of penis in males 
Glands e.g. bartholin in females 
Perineal muscles that provide support to the external genitalia e.g. bulbospongiosus or ischiocavernous muscles

Question 11

What are the bones of the articulated pelvis?

Answer 11

Sacrum
Ileum, pubis, ischium
Ischial tuberosity
Ischial spine

Question 12

What are the joints of the articulated pelvis?

Answer 12

Sacroiliac
Sacrococcygeal
Pubic symphysis

Question 13

What are the ligaments of the articulated pelvis?

Answer 13

Sacrospinous
Sacrococcygeal
Sacrotuberous
Sacroiliac

Question 14

The pelvic brim/pelvic inlet is formed by the:

Answer 14

Premontory and ala of the sacrum
Arcuate line
Pectineal line

Question 15

What is the function of the pelvic brim/inlet?

Answer 15

Separates the true pelvis from the greater pelvis

Question 16

What are the borders of the true pelvic cavity?

Answer 16

Sacrum/coccyx - posterior
Pubic symphysis - anterior
Pelvic diaphragm - inferior 
Pelvic brim - superior 
Obturator internus muscle - lateral

Question 17

What are the contents of the true pelvic cavity?

Answer 17

Reproductive organs and tracts
Bladder
Rectum

Question 18

Name the pelvic musculature that line the wall of the pelvis:

Answer 18

Piriformis

Obturator internus

Question 19

Name the pelvic musculature that line the pelvic floor

Answer 19

Coccygeus

Levator ani

Question 20

Which muscles make up the Levator ani?

Answer 20

Iliococcygeus
Pubococcygeus
Puborectalis

Question 21

Origin and insertion of the piriformis?

Answer 21

Origin: Anterior surface of the sacrum
goes through the greater sciatic foramen i.e. over the ischial spine
Inserts onto the greater trochanter of the femur

Question 22

Origin & insertion of the Obturator internus

Answer 22

Origin: internal surface of the obturator membrane
Through the lesser sciatic foramen (below ischial spine)
Inserts on to the greater trochanter of the femur

Question 23

Origin and insertion of the coccygeal

Answer 23

Origin: ischial spine
Insertion: inferior end of the sacrum and coccyx

Question 24

Iliococcygeus

Answer 24

Origin: tendinous arch

Insertion Anococcygeal body

Question 25

What is the tendinous arch?

Answer 25

A line extending from the ischial spine to the posterior aspect of the pubic bone

Question 26

Pubococcygeus

Answer 26

Origin: posterior aspect of the pubic bone Insertion: Lateral fibres insert to the coccyx Medial fibres insert onto the contralateral fibres of the pubococcygeus itself

Question 27

Puborectalis:

Answer 27

Continuous muscle that Origin: Posterior aspect of the pubic bone Slings behind the rectum

Question 28

What is the blood supply to the pelvis?

Answer 28

Anterior division of the iliac (uterine, vesicular and internal pudenal arteries) Gonadal arteries supply the gonads

Question 29

Where do the gonadal arteries come off the abdominal aorta and why?

Answer 29

Just below the level of the renal arteries | because during development the gonads develop very close to the kidneys

Question 30

Veins draining the pelvis?

Answer 30

Internal iliac vein - to the common iliac veins | Gonadal veins - draining to the IVC or L renal vein

Question 31

What are the somatic plexuses of nervous control of the pelvis?

Answer 31

Lumbosacral (L4-S4 joined by lumbar L4/L5) | Coccygeal (S4 -Co)

Question 32

What are the nerves supplying the pelvic region?

Answer 32

Sciatic nerve Superior gluteal Inferior gluteal Pudendal nerve

Question 33

What are the visceral plexuses in this region?

Answer 33

Paravertebral/prevertebral Sympathetic/parasympathetic/visceral fibres e.g. for erection/ejaculation e.g. inferior hypogastric plexus

Question 34

Which foramen does the obturator nerve go through?

Answer 34

Obturator foramen

Question 35

What are the nerve roots of the superior gluteal nerve?

Answer 35

L4, L5, S1

Question 36

What are the nerve roots of the inferior gluteal nerve?

Answer 36

L5, S1, S2

Question 37

What are the nerve roots of the sciatic nerve?

Answer 37

L4, L5, S1, S2

Question 38

What are the nerve roots of the pudendal nerve?

Answer 38

S2, S3, S4

Question 39

What type of innervation are the pelvic splanchnic nerves?

Answer 39

Parasympathetic

Question 40

What time of innervation are the sacral sympathetic trunk, superior and inferior hypogastric plexuses?

Answer 40

Sympathetic

Question 41

What nerve goes out through the greater sciatic foramen and inferior to the piriformis, around the ischial spine and back in through the inferior sciatic foramen

Answer 41

Pudendeal nerve

Question 42

What area does the pudendal block numb?

Answer 42

The areas supplied by the pudendal nerve

Question 43

How do you find the pudendal nerve and administer the pudendal block

Answer 43

Because the pudendal nerve wraps around the ischial spine, you palpate for ischial spine and administers the anaesthetic to this area to block the whole pudendal region