Pelvic Cavity & Peritoneum

Question 1

Mention bounds of pelvic cavity

Answer 1

Behind & above: sacrum & coccyx
In front & below: symphsis pubis & pubic bodies
On each side: pelvic surfaces of ilium, ischium, rami of ischium & pubis & obturator membrane

Question 2

List contents of pelvic cavity

Answer 2

Ant: urinary bladder & prostate in male
Post: pelvic colon & rectum
Intermediate: in male: vas deferens & seminal vesicles, in female: uterus, ovaries, uterine tubes, vagina

Question 3

Compare pelvic peritoneum in male & female

Answer 3

M, peritoneum is reflected at the junction of middle & lower thirds of rectum on urinary bladder forming recto-vesical pouch (7.5 cm above anal orifice), then covers upper part of urinary bladder & covers ant abdominal wall
F, peritoneum is reflected at the junction of middle & lower thirds of rectum on posterior wall of vagina forming recto-uterine or Douglas pouch (5.5 cm above anal orifice) then peritoneum is reflected from ant wall of uterus at junction of body & cervix on sup surface urinary bladder (utero-vesical pouch).

Question 4

Describe bounds of perineum

Answer 4

Ant: pubic arch & inf pubic ligament
Post: tip of coccyx
Lat: ischial tuberosities
Ant-lat: conjoint ischial & pubic rami
Post-lat: sacrotuberous ligament

Question 5

Anal triangle contains……, urogenital triangel contains…….

Answer 5

Anal canal in median place & ischiorectal fossae on each side
Urethra & external genital organs & perineal pouches

Question 6

Mention bounds of ischiorectal fossa

Answer 6

Apex: thin edge at junction of obturator internus & levator ani
Base: skin on side of anal orifice
Ant: post border of perineal membrane & posterior aspect of muscles of UG triangle
Post: sacrotuberous ligament covered by lower border of gluteus maximus
Lat wall: vertical formed by lower part of obturator internus & its fascia & ischial tuberosity
Med wall: is sloping downwards & medially formed by inf surface of levator ani & external anal sphincter

Question 7

List contents of ischiorectal fossa

Answer 7

1. Fat that allows distension of anal canal
2. Structures in pudendal canal: pud n, internal pud v
3. Inferior rectal n & v supply levator ani & external anal sphincter
   Smaller structures: posterior scrotal or labial n & v, perineal v, perineal branch of 4th sacral n.

Question 8

Define pudendal canal

Answer 8

A passage in obturator fascia that covers medial aspect of obturator internus, it allows passage of pudendal n & int pud v to perineum

Question 9

Describe course of pudendal n

Answer 9

One of terminal branches of sacral plexus (S2,3&,4), in pelvis it descends infront of piriformis then leaves pelvic caivity to gluteal region through greater sciatic foramen, then crosses sacrospinous ligament & enters lesser sciatic foramen to pass through pudendal canal to reach perineum.

Question 10

Describe course & braches of internalnpudendal a

Answer 10

One of terminal branches of sacral plexus (S2,3&,4), in pelvis it descends infront of piriformis then leaves pelvic caivity to gluteal region through greater sciatic foramen, then crosses the tip of ischial spine between pudendal n & n to obturator internus & enters lesser sciatic foramen to pass through pudendal canal to reach perineum. It enters deep perineal pouch & pierces the perineal membrane to enter the superficial perineal pouch ends by dividing into deep & dorsal arteries of penis

Question 11

List branches of pudendal nerve & what they supply?

Answer 11

1. Inferior rectal nerve: passes medially across the ischiorectal fossa and gives off motor branches to levator ani & external anal sphincter & sensory branches to skin around the anus.
2. Perineal n: to muscles of superficial & deep perineal pouches & sensory n (posterior scrotal or labial n)
3. Dorsal n of penis & clitoris supplies corpora cavernsa of penis & its skin

Question 12

List branches of internal pudendal art

Answer 12

1. Inferior rectal art
2. Perineal art: divides into transverse branch (to transverse perineal muscles & perineal body) & 2 post sacral (or labial) arteries that supply skin of scrotum (or labium majus)
3. Artery of bulb
4. Urethral artery
5. Deep art of penis
6. Dorsal art of penis

Question 13

List the fasciae dividing urogenital triangle into compartments

Answer 13

1. Deep membranous layer of superficial fascia
2. Inferior fascia of UG diaphragm or perineal membrane
3. Superior fascia of UG diaphragm

Question 14

Describe relation of the perineal fasciae:
1. Anteriorly
2. Posteriorly

Answer 14

1. The sup & inf fasciae of UG diaphragm fuse a little behind symphsis pubis, but membranous layer of superficial fascia continues with that of anterior abdominal wall and does not unite with the other 2 membranes.
2. All three membranes are attached together

Question 15

Describe attachments of perineal membrane

Answer 15

Posteriorly, is fused with perineal body with superior fascia of UG diaphragm and with membranous layer of superficial fascia
Lateral margins are attached to ischiopubic ramus
Ant apex is fused with superior fascia of UG diaphragm so closing deep perineal pouch ant. It is thickened forming transverse perineal ligament which is separated from inf pubic ligament by gap through which oass the deep dorsal vein of penis & dorsal n of penis or clitoris

Question 16

List structures piercing perineal membrane

Answer 16

A. UG structures: urethra & ducts of bulbo-urethral gland (male) or urethra & vagina (female)
B. Vessels (arteries): artery of bulb of penis or vestibule, urethral arteries, deep & dorsal arteries of penis or clitoris, posterior scrotal or labial vessels.
C. Nerves: nerves of bulb of penis or vestibule & posterior scrotal or labial nerves

Question 17

Describe bounds of superficial perineal pouch

Answer 17

Inf: membranous layer of the superficial layer
Sup: pernial membrane
On each side: pubic arch to which roof & floor are attached
Post: the pouch is closed by fusion of membranes
Ant: it is open and cont with the interval between the membranous layer of the superficial fascia of the anterior abdominal wall and the aponeurosis of external abdominal oblique.

Question 18

Mention contents of superficial perineal pouch

Answer 18

A. UG
1. root of penis (2 crura and bulb) (root of clitoris in female)
2. Part of urethra in male (two bulbs of vestibule around urethral & vaginal orifices in female)
3. Ducts of bulbourethral glands in male (greater vestibular glands in female)
B. Muscles:
1. Two ischiocavernosi muscles coveing crura of penis (or crura of clitoris)
2. A median bulbospongiosus muscle covering bulb of penis (or 2 bulbospongiosi muscles covering bulbs of vestibule)
3. Two superficial transversei perinei muscles
C. Vessels: same as piercing perineal membrane
D. Nerves: dorsal n of penis or clitoris & posterior scrotal nerves or posterior labial arteries

Question 19

Describe bounds of deep perineal pouch

Answer 19

Floor: perineal membrane
Sup: superior fascia if UG diaphragm
On each side: ischiopubic rami
Ant & post: fusion of perineal membrane with the superior fascia of the UG diaphragm so it is a closed space

Question 20

Mention contents of deep perineal pouch

Answer 20

In male:
Membranous urethra, a pair of bulbourethral glands, sphincter urethrae & deep tranversei perinei muscles (both from UG diaphragm), termination of internal pudendal artery, dorsal n of penis
In female:
Part of urethra, part of vagina, sphincter urethrae & deep tranversei perinei muscles (both from UG diaphragm), termination of internal pudendal artery, dorsal n of clitoris