Pelvic Vasculature and Perineum Flashcards
1
Q
Internal Iliac Artery (branch off what, enters true pelvis to supply what, divides into what)
A
branch of common iliac artery
enters true pelvis to supple pelvic viscera, pelvic walls, perineum, and gluteal region
divides into anterior and posterior divisons
2
Q
Posterior Division of Internal Iliac Artery (branches to what and name them)
A
branches to pelvic wall, lumbar region, and buttock
Iliolumbar Artery
Lateral Sacral Artery
Superior Gluteal Artery
3
Q
Iliolumbar Artery ( supplies what)
A
sends branches to iliac fossa and lower lumbar region
4
Q
Lateral Sacral Artery (course, supplies what)
A
descends anterior to sacrum
sends branches into the anterior sacral foramina to supply radicular branches to anterior spinal artery
5
Q
Superior Gluteal Artery (course, supplies what)
A
Passes posteriorly b/w lumbosacral trunk (anterior rami or L4,L5) and anterior ramus of S1
exits pelvis via greater sciatic foramen (superior to piriformis muscle) to supply gluteal muscles
6
Q
Anterior Division of Internal Iliac Artery (branches to what and name them)
A
supplies pelvic viscera, gluteal region, and thigh Obturator Artery Umbilical Artery Inferior Vesical Artery Middle Rectal Artery Vaginal Artery Uterine Artery Inferior Gluteal Artery Internal Pudendal Artery
7
Q
Obturator Artery (course)
A
passes w/ obturator nerve on lateral wall of pelvis, then through obturator foramen to supply medial thigh
8
Q
In 25% of people obturator artery comes from where and when is this an issue
A
inferior epigastric artery
can be an issue when repairing inguinal hernia
9
Q
Umbilical Artery (what does it give off and supply)
A
patent proximal part gives off 2-3 superior vesicle arteries- supply upper part of bladder
10
Q
Obliterated part of umbilical artery (what does it become)
A
forms medial umbilical ligament (fold)
11
Q
superior vesicle arteries
A
branches of umbilical artery and supply upper part of bladder
12
Q
Inferior Vesicle Artery (what does it supply, what is special about it)
A
supplies base (posterior wall) of urinary bladder, prostate, and seminal vesicles only found in males
13
Q
Middle Rectal Artery (course, in males can come from what artery)
A
passes medially to lower rectum, prostate, and seminal vesicle may arise from inferior vesicle artery in males often absent (especially females)
14
Q
Vaginal Artery (course)
A
passes to sides of vagina
15
Q
Uterine Artery (course, issue with course)
A
crosses superior to ureter to enter broad ligament of uterus
problem in hysterectomy because wanna cut artery not ureter
16
Q
Inferior Gluteal Artery (course)
A
passes posteriorly b/w anterior rami of S1 and S2 or S2 and S3
leaves pelvis by passing b/w performs muscle and coccyges muscles (artery inferior to piriformis)
passes through greater sciatic foramen to supply gluteal region
17
Q
Internal Pudendal Artery (course)
A
first passes b/w piriformis and coccygeus muscles and leaves pelvis via greater sciatic foramen to enter gluteal region
courses inferiorly, posterior to ischial spine and sacrospinous ligament and then passes through lesser sciatic foramen to enter the perineum
18
Q
Internal Pudendal Artery (supply)
A
main blood supply to structures of perineum
19
Q
Why does the internal pudendal artery leave true pelvis via greater sciatic foramen and reenter via the lesser sciatic foramen
A
pelvis diaphragm supports viscera and if artery penetrated it there would be a site of potential weakness and result in herniation of pelvic viscera into perineum
20
Q
perineum (what is it)
A
diamond-shaped region of true pelvis inferior to pelvic diaphragm
21
Q
Perineum (anterior to posterior boundaries)
A
pubic symphysis to tip of coccyx
22
Q
Perineum (lateral boundaries)
A
pubic arches
ischial rami
ischial tuberosities
sacrotuberous ligament
23
Q
the perineum is subdivided by an imaginary line passing though ischial tuberosities creating what?
A
two triangular regions:
urogenital triangle
anal triangle
24
Q
urogenital triangle (what is it, contents)
A
anterior triangle of perineum
contains urogenital structures- root of penis (male), vulva (external gentialia of female), urogenital diaphragm
25
Anal triangle (what is it, contents)
posterior triangle of perineum
| contains- anal canal and adjacent external anal sphincter as well as ischiorectal fossa
26
urogenital diaphragm (where is it)
located inferior to urogenital gap in pelvic diaphragm
| part of urogenital triangle
27
anal triangle (borders)
posterior: tip of coccyx
lateral: sacrotuberous ligament
anterior: imaginary transverse line through ischial tuberosities
28
ischiorectal fossa (borders)
base of wedge: located superficially at skin surrounding anus
lateral side of wedge: obturator internus muscle
medial side of wedge: pelvic diaphragm and anal canal
29
ischiorectal (ischioanal) fossa (what is it, what does it contain)
wedge-shaped
fat filled- supports anal canal
contains- pudendal nerve and internal pudendal artery and vein (coursing anteriorly and inferiorly along lateral wall)
30
anterior recess of ischiorectal fossa is where
b/w pelvic diaphragm and urogenital diaphragm in urogential triangle
31
what supports the anal canal, allowing for distention during dedication
ischiorectal fossa
32
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Pudendal Canal (Alcock's canal)
(what is it, what does it contain)
```
fascial canal within obturator internus fascia on lateral wall of ischiorectal fossa
contains pudendal neurovascular bundle
extends from lesser sciatic foramen (posteriorly) to urogenital diaphragm (anteriorly)
33
Pudendal Nerve (formed from what)
anterior rami of S2-4 of sacral plexus
34
Pudendal Nerve (what type of nerve is it)
somatic (voluntary) nerve
| somatic innervation to most of perineum
35
Pudendal Nerve (course)
passes out of main pelvic cavity via inferior part of greater sciatic foramen to enter gluteal region
descends posterior to ischial spine
passes through lesser sciatic foramen to enter pudendal canal
36
Pudendal Nerve (branches)
branching occurs in anal triangle:
Inferior rectal nerve
branches to structures of urogenital triangle (dorsal nerve of penis/clitoris and posterior scrotal/labial nerves)
37
Internal Pudendal Artery (branches)
Inferior rectal artery
| branches to structures of urogenital triangle (dorsal branches to penis and clitoris)
38
how does lower half of anal canal get blood supply
inferior rectal artery (branch off internal pudendal, which is branch of internal iliac)
39
Anal Canal (course)
terminal part of large intestines
begins at narrowing of rectal ampulla at level of pubertal sling of pelvic diaphragm
bent at angle at anorectal junction
descends posteroinferiorly to anus b/w anococcygeal body and perineal body
40
what is landmark for beginning of anal canal
coccyx
41
Internal Anal Sphincter (what is it, innervation)
thickening of smooth circular muscle of upper part of anal canal wall
involuntary- parasympathetic
42
parasympathetic stimulation of the internal anal sphincter does what
relaxes sphincter
43
external anal sphincter (what is it, innervation)
striated muscle surrounding lower part of anal canal
extends from perineal body to anococcygeal body
voluntary- inferior rectal nerve
44
Name the parts of the external anal sphincter
Deep part
Superficial part
Subcutaneous part
45
Deep Part of External Anal Sphincter (what does it do)
fuses with adjacent puborectalis muscle of pelvic diaphragm
46
Superficial Part of External Anal Sphincter (what does it do)
moors anal canal in median place by its attachments to perineal body and anococcygeal body
47
Subcutaneous Part of External Anal Sphincter (what does it do)
slender
| surrounds anus
48
external anal sphincter (action)
closes anal canal
49
whats responsible for the bend at anorectal junction
puborectalis
50
Puborectalis aids closure of anorectal junction how
drawing posterior wall of anal canal anteriorly, keeping posterior wall of anorectal junction opposed to anterior wall except during defecation
51
Anorectal ring (what is it, what is it composed of)
palpable landmark during rectal exam
| composed of depp part of external anal sphincter, puborectalis, and internal anal sphincter
52
anorectal ring determines what about a patient
continence
53
Anal Columns (what are they, what do they contain)
characteristic vertical folds of mucus membrane
| contain superior rectal vessels
54
location of portal-caval anastomosis
anal columns
55
anal valves (what are they)
semilunar epithelial folds joining inferior ends of anal columns
56
what structures indicate the pectinate line
anal valves
57
what does the pectinate line mark
juncture between hindgut endoderm and ectoderm of proctodeum
58
location of embryonic anal membrane (former cloacal membrane)
anal valves
59
anal sinuses (what are they)
recesses superior to anal valve and between anal columns
60
upper half of anal canal gets blood from where
superior rectal artery and vein from inferior mesenteric artery and vein
61
upper half of anal canal drains lymph through where
inferior mesenteric nodes
62
upper half of anal canal is innervated by what
stretch receptors and other visceral afferents send sensory fibers into hypogastric plexus of autonomic system
no somatic sensory fibers so area not so sensitive
63
lower half of anal canal is innervated by what (what does it respond to)
somatic sensory fibers from inferior rectal nerve (branch of pudendal nerve)
respond to pain, touch, and temp
very sensitive
64
lower half of anal canal is gets blood supply by what
inferior rectal artery
65
lower half of anal canal drains lymph through what
medial nodes of superficial inguinal lymph nodes (inferior to inguinal ligament)
66
what can be torn by hard stools in a chronically constipated patient, tearing anal mucosa
anal valves
67
tearing of anal valves can cause what
anal canal to be infected and from fistula through wall of anal canal into the ischiorectal fossa- can result in perianal abscess
68
perianal abscess (what is it)
collection of pus in fat in ischiorectal fossa
69
Perianal Abscess (how can it spread)
from one side to the opposite sid
anteriorly into anterior recess of ischiorectal fossa (b/w elevator ani and urogenital diaphragm) to affect urogenital structures
70
Internal Hemorrhoids (what are they)
varicosities of tributaries of superior rectal veins in anal columns covered by mucous membrane of anal columns
71
External Hemorrhoids (what are they)
varicosities of tributaries of interior rectal veins covered by skin (very painful- somatic fibers of inferior rectal nerve)
72
Urogenital Triangle (location)
anterior part of perineum
| below part of pelvic diaphragm which has a central urogenital gap
73
Urogenital Triangle (boundaries)
posterior- imaginary line b/w ischial tuberosities
| lateral- inferior rami of pubis and ramus of ischium
74
Urogenital Diaphragm (location)
inferior to pelvic diaphragm
| b/w and attached to inferior rami of pubis and rami of ischium
75
Urogenital Diaphragm (function)
prevent herniation (or prolapse) of bladder, prostate, and uterus through cleft in pelvic diaphragm
76
Urogenital Diaphragm (what is it)
layer of muscles superior to a layer of fascia
77
Urogenital Diaphragm (what passes through it)
urethra (both sexes)
| vagina
78
Deep Perineal Pouch (how is it formed)
superior and inferior fascial layers fuse anteriorly and posteriorly (also fuse with perineal body)
79
Deep Perineal Pouch (what is it)
space between superior and inferior fascial layers of urogenital diaphragm
striated muscles and bulbourethral glands (males)
80
Deep Perineal Pouch (muscular components)
Deep transverse perineal muscle
| Sphincter urethrae
81
Deep Perineal Pouch (non-muscular contents in males )
membranous urethra
bulbourethral glands
Internal pudendal artery, vein, and nerve branches
82
Deep Perineal Pouch (non-muscular contents in females )
urethra
vagina
internal pudendal artery, vein, and nerve banches
83
Deep transverse perineal muscle (action and innervation)
action: stabilizes perineal body, reinforces pelvic diaphragm
innervation: perineal branch of pudendal nerve
84
Sphincter Urethrae (action and innervation)
action: voluntary sphincter of urethra (relaxed during urination)
functions to eject last bit of urine
functions in ejaculation
innervation: perineal branch of pudendal nerve
85
membranous urethra (what is it)
thinnest, shortest, narrowest, and least dilatable part of urethra
86
what is subject to tear in the deep perineal pouch during insertion of a catheter in a male
membranous urethra
87
Inferior fascial layer (perineal membrane)
| what is it, attachments
thick fascial layer
attached laterally to ischiopubic rami
posteriorly to perineal body
88
Superficial Perineal Pouch (what is it)
space in urogenital triangle between inferior fascial later of urogenital diaphragm and the superficial perineal fascia
89
Superficial Perinal Fascia (Colle's Fascia)
| what is it
continuation of Scarpa's fascia from lower anterior abdominal wall
90
Superficial Perinal Fascia (Colle's Fascia)
| attachments
attaches posteriorly to perineal body and posterior border of urogenital diaphragm
laterally to ischiopubic rami
91
extravasated urine from a ruptured penile urethra can enter where?
superficial perineal pouch and scrotum
| anterior abdominal wall
92
extravasated urine from a ruptured penile urethra cannot enter where?
```
ischiorectal fossa (due to attachment of superficial perianal fascia to urogenital diaphragm posteriorly)
thigh (due to attachment of superficial perineal fascia to the ischiopubic rami laterally)
```
93
bulbourethral glands (where are they, what are they)
present posterior to membranous urethra (deep perineal pouch)
ducts pass through inferior fascia layer of urogenital diaphragm and open into penile (or spongy) uretha in bulb of penis
94
bulbourethral glands secretions are what?
a lubricant during sexual arousal
95
penile urethra (where is it)
aka spongy urethra and is in the bulb of penis
96
Superficial Perineal Pouch (contents)
```
root of penis and clitoris (fixed portion)
superficial transverse perineal muscle
bulbospongiosus muscle
ischiocavernosus muscle
greater vestibular glands (female only)
```
97
superficial transverse perineal muscle (what does it do)
fix position of perineal body
| support floor of pelvis
98
bulbospongiosus muscle (what does it do)
covers bulb of penis or bulb of vestibule (female)
99
ischiocavernosus muscle (what does it do)
covers crura of penis or clitoris
100
Penis (what is it composed of, what are its division)
composed of three masses of erectile tissue
| divided into root (fixed within urogenital triangle) and body (free anterior portion)
101
Root of penis (where is it, what are its divisions)
located inferior and fixed to urogenital diaphragm
two parts:
crura of penis
bulb of penis
102
Crura of penis (what are they)
paired laterally placed erectile tissues
103
Crura of penis (where do they attach)
attach to inferior ramus of pubis and ramus of ischium
| firmly attached to the underside of inferior fascial layer of urogenital diaphragm
104
Bulb of penis (what is it)
single centrally located erectile tissue
105
Bulb of penis (attachment)
firmly attached to underside of inferior facial layer (perineal membrane) of urogenital diaphragm
106
Bulb of penis (contents)
proximal portion of penile (or spongy) part of urethra
107
what muscles are associated with root of penis
bulbospongiosus muscle
| ischiocavernous muscle
108
bulbospongiosus muscle in males (origin)
median raphe, perineal body
109
bulbospongiosus muscle in males (insertion)
fibers cover bulb of penis
| anterior fibers extend over proximal part of corpora covernosa
110
bulbospongiosus muscle in males (actions)
aids in emptying urethra during micturition and ejaculation
| contributes to erection by compressing blood engorged bulb of penis
111
ischiocavernosus muscle in males (origin)
ischial tuberosity
112
ischiocavernosus muscle in camles (insertion)
covers medial side of undersurface of crus of penis
113
ischiocavernosus muscle in males (action)
aids in erection by compressing crus of penis
114
Body of penis (what is it)
continuation of crura and bulb of penis
115
part of penis not located in superficial pouch
body of penis
116
Body of penis (consists of what)
corpora cavernosa
| corpus spongiosum
117
corpora cavernosa (what/where is it)
dorsally (superiorly) located cylinders of erectile tissue
| continuation of crura
118
corpus spongiosum (what/where is it)
ventrally (inferiorly) located cylinder
| continuation of bulb of penis
119
corpus spongiosum expands distally as
glans penis
120
corpus spongiosum (contents)
distal part of penile (spongy) urethra
| navicular fossa
121
navicular fossa (what is it)
dilated part of penile urethra in the glans penis
| terminates at external urethral orifice
122
Facial layers of penis (name them)
```
prepuce
suspensory ligament of penis
fundiform ligament of penis
superficial penile fascia
deep penile fascia
tunica albugina
```
123
prepuce (what is it)
folded double layer of superficial penile fascia and skin that surrounds glans penis
124
what is removed during circumcision
prepuce
125
suspensory ligament of penis (what is it)
arises from pubic symphysis and inserts into facia surrounding penis
126
fundiform ligament of penis (where does it attach)
descends from linea alba to attach to penile fascia
127
superficial penile fascia (what is it continuous with)
continuous with Scarpa's (membranous) fascia of anterior abdominal membrane and dartos facia and superficial perineal fascia of superficial perineal pouch
128
Deep penile fascia (Buck's fascia)
| where is it, what does it do
located deep to superficial dorsal vein of penis
| encloses deep dorsal arteries and veins of penis and corpora of penis
129
tunica albuginea of penis (what does it do)
directly invests corpora cavernous with very thick layer of dense fascia to hold two corpora together
130
tunica albuginea of penis (what does it form
fuses in midline of penis to form a septum
131
Artery of bulb supplies what
erectile tissue of bulb of penis and corpus spongiosum
132
blood supply of penis are branches from what
internal pudendal artery
133
what branches of internal pudendal artery supply the penis
artery of bulb
deep artery of the penis
dorsal artery of the penis
134
what veins drain the penis
deep dorsal vein of penis
| superficial dorsal vein of penis
135
deep arteries (artery of crus) of the penis supplies what
erectile tissues of crura and corpora cavernosa
136
dorsal artery of the penis supplies what
skin of penis, fascial sheath surrounding erectile tissues
137
what anastomosis occurs in penis and where
dorsal artery of penis and artery of bulb at glans penis
138
dorsal vein of penis (location, drains from where to where)
midline of penis
drains blood from corpora of penis
drains into prostatic venous plexus and/or vesicle venous plexus
139
superficial dorsal vein of penis (drains what to where)
drains blood from skin and fascia into superficial external pudendal vein
140
sensory innervation of penis
dorsal nerve of penis (branch of pudendal)- passes through deep perineal pouch
141
skin of penis drains to what lymph nodes
superficial inguinal nodes
142
deep structures of penis drain to what lymph nodes
internal iliac nodes
143
erection (what type of nerve fibers and what do they cause to happen)
parasympathetic
| cause relaxation of smooth muscle in deep arteries of penis and artery to bulb
144
erection (what is happening)
parasympathetics relax muscle of arteries
blood flows to erectile tissues, engorging them
veins surrounding erectile tissues become compressed and blood ceases to drain
145
erection (what nerve is involved and how)
pudendal nerve
innervates bulbospongiosus and ischiocavernosus muscles- compress venous plexus at periphery of bulb and crura to stop venous drainage
146
what do sympathetics do to an erection
cessation of erection- constriction of smooth muscles of arteries
147
ejaculation (what kind of nerve fibers, what do they do)
sympathetics
cause contraction of smooth muscle of urethra to expel semen
close sphincter vesicae at neck of bladder to prevent reflux of semen into bladder
148
ejaculation (what nerve is involved and how)
pudendal nerve
| cause contraction of bulbospongiosus muscle to compress penile urethra
149
clitoris (what are the parts)
crura of clitoris
| bulbs of vestibule
150
crura of clitoris (what are they, where do they attach)
pair of laterally located erectile tissues
| attached to inferior ramus of pubis and ischium
151
crura of clitoris (what do they become)
body of clitoris anteriorly
152
bulbs of vestibule (what are they)
homologous to bulb of penis but split into two halves by orifice of vagina and urethra
153
bulbs of vestibule (what do they become)
glans clitoris (homologous to glans penis)
154
urethra does or does not enter body of clitoris or bulbs of vestibule
does not
155
bulbospongiosus muscle in females (where does it attach, describe location)
attached to perineal body
| cover bulb of vestibule and extend around vagina to body of clitoris
156
bulbospongiosus muscle in females (action)
diminishes vaginal opening
157
ischiocavernosus muscle in females (attached to where, describe location)
attached to ischial tuberosity
| cover surface of crus clitoris
158
ischiocavernosus muscle in females (action)
aids in erection of clitoris by compressing blood-engorged erectile tissue of crura
159
Greater vestibular glands (Bartholin's glands)
| what are they
two roundish glands deep to bulb of vestibule in superficial perineal pouch
have duct that opens lateral to vaginal orifice
160
Greater vestibular glands (Bartholin's glands)
| what do they secrete
lubricating mucus
161
Greater vestibular glands (Bartholin's glands)
| what are they analogous to in males
bulbourethral glands
162
mons pubis (what is it)
mass anterior to pubic symphysis
| formed by pad of fat and covering of hair
163
labia majora (what are they, what do they correspond to in males)
two folds of skin, filled with fat, covered with hair
| correspond to scrotum
164
anterior labial commissure (what is it)
where two labia majora meet anteriorly at midline
165
posterior labial commissure (what is it)
where two labia majora meet posteriorly at midline
166
labia minora (what are they)
two folds of skin devoid of fat and hair
167
labia minora (where are they)
between labia majora and vaginal and urethral orifices
168
the labia minora unite posteriorly as what
fourchette or frenulum of labia minora
169
labia minor split anteriorly to cover clitoris as what
prepuce of clitoris
| referred to as clitoral hood
170
vestibule of vagina (what is it)
area between labia minora
171
urethral orifice and vaginal orifice are found in what structure
vestibule of vagina
172
```
paraurethral glands (Skene's glands)
(what are they homologous to in males)
```
homologous to prostate gland
173
```
paraurethral glands (Skene's glands)
(where do they open)
```
open on either side of urethral orifice
174
sensory innervation of clitoris is done by what nerve
dorsal nerve of clitoris (branch of pudendal)
175
overstitching of the vaginal opening during childbirth can lead to tearing of what and results in what
perineal body
results in weakness of pelvic diaphragm and may result in collapse of rectum and bladder against vaginal wall or prolapse of uterus through vaginal orifice
176
mediolateral episiotomy (what is it, what does it prevent)
surgical cutting of the vagina and posterior wall of vulva (lateral to perineal body) to enlarge vaginal orifice
prevents tearing of perineal body
177
median episiotomy (what is it)
midline incision of the of posterior wall of the of vagina, forchette and perineal body
(incision of perineal body can easily be repaired compared to jagged tear from overstretching)
178
what episiotomy is more common and why
mediolateral episiotomy is more common
| in median physician at risk to cut external anal sphincter
179
Pudendal nerve block (what is it used for)
anesthetize perineum prior to an episiotomy
180
transvaginal approach to pudendal nerve block (how is it done)
find ischial spine via transvaginal palpation
needle passed though vaginal wall toward the ischial spine and though sacrospinous ligament
injection of anesthetic once through sacrospinous ligament
181
perineal method of pudendal nerve block (how is it done)
ischial tuberosity is palpated externally though buttock
| needle inserted in skin medial to ischial tuberosity and placed 1 inch deep from inferior border of tuberosity
