G26 27 Perineum

Question 1

episiotomy

Answer 1

surgical incision in perineal body, from posterior end, into posterior vaginal wall

performed with a pudendal anesthesia

-avoids trauma to perineal body

Question 2

ischioanal fossa

Answer 2

fat filled space lateral to anal canal.

lateral wall: obterator internus, fascia, ischial tuberosity
medial wall levator ani and anal canal

allows dilation of anal canal

roof of fossa: where obturatur internus and levator ani meet

communicate around anus POSTERIORLY, superior to anococcygeal ligament

Question 3

anterior recess of perineal body

Answer 3

projects anteriorly into UG triangle superior to perineal membrane (deep pouch)

important to understand spread of infection, can move from anterior recess to the pelvic cavity

Question 4

anal triangle

Answer 4

coccyx, sacrotuberous ligaments, ichial tuberosities, imaginary line between the ischial tuberosities

houses anal canal, external anal sphincter, ischioanal fossae, perineal body

Question 5

anal canal

Answer 5

site of portal -caval anastomosis ,

anal columns: folds in mucosa, terminal branches of superior rectal artery and vein

anal valvesL crescent shaped, unite the columns

anal sinuses: depressions, sup. to each anal valve

pectinate line: formed byu the anal valves

division between ectodermal and endodermal parts
endoderm:supplied by superior rectal artery,
innervated by ANS, stretch but not pain/temp/touch
lymphatics to internal iliac and inferior mesenteric\

ectoderm: inferior to pectinate line, supplied by inf rectal artery, site of EXTERNAL HEMORRHOIDS
-innervated by the inferior rectal nerve (somatic)-very sens to touch, pain, temp
lymphatics to inguinal nodes

blood supply:
-superior to pectinate line: superior rectal artery/vein (from IMA to portal system)

-inferior to pectinate line: from internal iliac??

Question 6

Hemorrhoids

Answer 6

internal hemorrhoids: distensions of veins of interval venous plexus (portal hypertension)

external hemorrhoids: distesnsion of veins of external venous plexus ( blocks drainage)
-visible

Question 7

internal and external anal sphincter

Answer 7

smooth muscle (INVOLUNTARY)
sympathetic stim
parasympathetic inhibition: sensitive to stretch
tonic contraction: until defacation

external: skeletal muscle
not until 18mo
voluntary
somatic 
inferior rectal nerve S4
continuous with puborectalis
deep, superficial, and subcutaneous parts

Question 8

two types of erectile tissue

Answer 8

corpora cavernosa (crura)
-body of clitoris (has suspensory lig)/post parts of penis

corpus spongiosum:

• bulb of penis, anterior part of penis, glans penis, penile urethra
• bulbs of the vestibule, not clitoris, creates glans clitoris

male: corpora cavernosa bouch to corpus spongiosum by deep (bucks) fascia

Question 9

three muscles in superior perineal pouch

Answer 9

ischiocavernosus
o: internal surface of ischiopubic ramus and ischial tuberosity
I: inferior and medial aspects of crus and perineal membrane
I deep branch of pudendal nerve
aL aids in erection
-COVER THE CRURA

bulbospongiosus: paired muscles in male and female
mo: median raphe and perneal body
foL perineal body
Mi: perineal membrase proximal corpus spongiosum and corpora cavernosa
fi:pubic arch, bubls of the vestibule, corpora cavernosa
in: ddep and sup branches of pudendalj
action: erection, and urination ejaculation males

superficial transverse perineal muscle:
o internal surface of ischioppubic ramus and ischial tuberosity
insertion perineal body
inn: deep pudendal
action aids in resisting increased intraabdomional pressure and stabilizes pernineal body

Question 10

glands

Answer 10

females: greater vestibular glands (of bartholins) located just posterior to bulbls of the vestibule

ducts from glands open to vag and secrete mucus

infection or formation of cysts common

Question 11

neurovasculature

Answer 11

superficial pouch

perineal branches of internal pudendal AV, pudendal N (S234)

Question 12

Cowpers Glands

Answer 12

Bulbourethral glands, ducts leave deep pouch and enter the penile urethra

Question 13

alcocks canal and association

Answer 13

S234 first pass through lesser sciatic foramen, then greater sciatic foramen (around the sacrospinous ligament) and then enter the alcocks canal. at this point it is the pudendal nerve, it then passes

dorsal nerve of the penis/clitoris. (through the deep pouch)

perineal nerve. superficial and deep branches

inferior rectal nerve: puborectalis (part of levator ani?)

nerve block of the pudendal for episiotomy
-through skin, through vagina, fingers between needle and fetus

internal pudendal artery follows same path then split into inferior rectal, perineal, dorsal artery of the clitoris, artery of the bulb, deep art of clit
dorsal or penis, deep artery of penis, artery of bulb, inferior rectal artery, perineal artery

deep dorsal vein of penis drains to prostatic venous plexus

superficial dorsal vein of penis drains to thigh

Question 14

space of retzius

Answer 14

at risk of pelvic fracture…venus and autonomic plexuses present (prostatic)

Question 15

lymphatic drainage of peritoneum

Answer 15

deep peritoneal tissue: accompany internal pudendal to internal iliac nodes
superficial tissues: superficial inguinal nodes
gonads: Lumbar nodes!

Question 16

deep perineal fascia

Answer 16

covers the bulbospongiosus muscle and ischiocavernosum muscle continuous with bucks fascia and fascia of external abdominal oblique, suspensory ligament, and fascia of spermatic chord
-all the same!

Question 17

Colles fascia

Answer 17

deep membranous layer of UG triangle
continuous with scarpas
dartos faschia in scrotum
superficial fascia of penis

slide 72

Question 18

space between two continuous (superficial and deep) fascias

Answer 18

superficial pouch?

perineal cleft: superficial fascia drops down in a cleft

Question 19

portions of the male urethra: 2 clinical correlations

Answer 19

prostatic

intermediate membraneous urethra
-prostate to bulb of penis (susceptible to injury)

spongy urethra

straddle injury: if injury takes place inferior to perineal membrane bloody urine enters perineal cleft
if injury takes place in between the perineal membrane and deep preineal fascia but the bloody urine cannot occupy a space
-so it breaks through the corpus spongiosum, and enter perineal cleft, blood and urine fill the space within the fascial layers in penis and ab wall….abdomen between EAO and scarpas….scrotum between ESF and superficial fascia, perineum between deep and colles

can also break superior to perineal membrane: goes into the abdominal pelvic cavity to diaphragm