Anatomy of the Pelvic Floor and Perinea Flashcards
(73 cards)
1
Q
Pelvic Musculature and Connective Tissue:
A
insert diagram
2
Q
Pelvic Diaphragm:
- forms
- is
- shape
A
- boundary between true pelvis and
perineum - musculature of floor of pelvis
- bowl-shaped
3
Q
Pelvic Diaphragm:
- muscles
A
- coccygeus
- levator ani: puborectalis,
pubococcygeus, iliococcygeus - obturator internis (lateral wall)
- piriformis (posterolateral wall)
4
Q
Pelvic Diaphragm:
- levator ani function
A
- dynamic support of
abdominopelvic viscera - urinary and faecal continence
5
Q
Pelvic Diaphragm: Puborectalis Attachments and Function:
A
- unilateral
- arises from the internal aspect of
the pubic bone of innominate - slings around the back of rectum
maintains faecal continence, when relaxed straightens anal canal to allow defecation
6
Q
Pelvic Diaphragm: Pubococcygeus:
A
- arises from the pubic bone of
innominate - attaches to the coccyx
7
Q
Pelvic Diaphragm: Iliococcygeus:
A
- arises from the tendonous arch of
obturator internis muscle - fascia thickens inferiorly which
iliococcygeus attaches to - passes inferiorly to attach to the
coccyx
8
Q
Obturator foramen filled by
A
obturator membrane
9
Q
Obturator internis attaches to
A
the pelvic aspect of the obturator membrane
10
Q
Pelvic Diaphragm:
A
insert diagram
11
Q
Pelvic Diaphragm:
A
insert diagram
12
Q
Pelvic Dipahragm:
A
insert table
13
Q
Pelvic Diaphragm:
A
insert table
14
Q
Pelvic Floor:
A
The pelvic floor consists of the pelvic diaphragm, associated fascia, deep perineal pouch and the perineal membrane
15
Q
What sits on the internal aspect of the piriformis muscle?
A
Nerves arising from the sacral plexus
16
Q
Pelvic Floor:
A
insert diagram
17
Q
Pelvic Fascia: Components:
A
- Deep pelvic fascia: parietal and
visceral - Endopelvic fascia:
- Superficial perineal fascia
18
Q
Pelvic Fascia:
A
insert slide
19
Q
Deep Pelvic Fascia:
A
- surrounds muscles and pelvic
viscera deep to the superficial
fascia - include deep and superficial
perineal pouches - parietal layer: covers muscles,
continuous with transversalis fascia
and iliopsoas fascia - visceral: forms adventitia of each
visceral structure in the pelvis
insert diagram
20
Q
Endopelvic Fascia:
A
- between layers of deep fascia
- not true ligaments because not
attaching bone to bone - fixing visceral structures to
bone/soft tissue structures
Female:
- uterosacral: uterus to sacrum
(posterior aspect of
endopelvic fascia)
- cardinal/transverse cervical: largest
- pubocervical
Male:
- rectovesical septum:
21
Q
The perineum includes all structures inferior to the
A
pelvic diaphragm
22
Q
Endopelvic Fascia:
A
insert diagram
23
Q
Superficial Perineal Fascia:
A
- Camper’s and Scarpa’s Fascia
insert diagram
24
Q
Endopelvic Fascia:
A
insert diagram
25
insert diagram
26
Perinea:
insert diagram
27
Perinea:
- Region
- surface anatomy boundaries
- superficial to inferior fascia of
pelvic diaphragm (deep pelvic
fascia)
- anterior: mons pubis/root of penis
- lateral: medial surface of thigh
- posterior: gluteal fold + inter-
gluteal cleft
28
Perinea:
insert diagram
29
Perinea: Osteological Boundaries:
- Anterior: pubic symphysis
- Anterolateral: ischiopubic rami
- Posterolateral: ischial tuberosities
and sacrotuberous ligament
- Posterior: coccyx
30
Osteological Boundaries of the Perinea:
insert diagrams
31
Perinea: Triangles:
- divided into 2 triangles by perineal
body transverse line
- Urogenital Triangle:
- anterior to transverse line
- subdivided by perineal
membrane (attachment of
erectile tissue) into pouches
Anal Triangle:
- posterior to transverse line
32
Perinea: Identify traingles:
insert diagram
33
Perinea: Urogenital Triangle: Contents:
- deep perineal pouch
- perineal membrane
- superficial perineal pouch
- external genitalia
deep -> superficial
insert diagram
34
Deep Perineal Pouch:
- location
- contents
- deep to perineal membrane
- urethra
- external urethral sphincter
- neurovasculature to penis/clitoris
Male:
- DTP: deep transverse perineal
muscle = skeletal
- bulbo-urethral glands
Female:
- DTP: deep transverse perineal
muscle = smooth muscle
35
Perinea: Deep Perineal Pouch: Bulbo-urethral Glands: Function:
- in males
- secretions to lubricate spongy
urethra
- ease passage of seminal fluid
36
Perinea: Deep Perineal Pouch:
insert diagrams
37
Perinea: Superficial Perineal Pouch:
- location
- contents
- superficial to perineal membrane,
deep to superficial perineal fascia
Contents:
- STP: superficial transverse perineal
muscle
- neurovasculature: deep perineal
branches
Male:
- root of penis (bulb and crura)
- penile musculature
- spongy urethra
crura = where two ischiocavernous muscles meet
bulb= bulbospongiosus muscle
Female:
- clitoris and musculature
- greater vestibular gland
- bulbs of vestibule and musculature
38
Superficial Perineal Pouch: Females:
insert diagram
39
Superficial Perineal Pouch: Males:
insert diagram
40
Tables:
insert muscles and locations
41
Perinea: External Female Genitalia:
- mons pubis: cushioning
- clitoris
- labia majora: fatty, head covered
- labia minora
- bulbs of vestibule: lie beneth
bulbospongiosus
- greater vestibular glands
- lesser vestibular glands
42
Perinea: External Female Genitalia:
insert diagrams
43
Table:
insert table
44
Perinea: External Male Genitalia:
- scrotum: cutaneous
fibromuscular structure that
contains the testis, associated
ducts and neurovasculature
- penis
45
Perinea: Male External Genitalia:
insert diagrams
46
Anal Triangle: Features:
- anus
- ischio-anal fossae:
*projects anteriorly
*communicating with deep perineal
pouch
*forms abscesses
*filled with superficial perineal
fascia
- posteriorly: skin and superficial
tissue
- superior: deep pelvic fascia
- anterior: deep perineal pouch and
perineal membrane
47
Anal Triangle:
insert diagram
48
What is the perineal body?
- central tendon of the perineum
- collagen and elastic fibers, with
smooth and skeletal muscle fibers
Site of convergence of muscles:
- bulbospongiosus
- deep and superficial transverse
perineal muscle
- external anal sphincter
- levator ani
49
What is shown below?
perineal body
insert image
50
Consequences of tearing through the perineal body:
- incontinence
- decreased sexual performance
51
If a patient presents with anal incontinence and erectile dysfunction consider damage to which anatomical body?
Perineal body
52
Perineal body:
insert diagram
53
- Gonadal arteries arise from the
anterior aspect of the abdominal
aorta at L2
- Abdominal aorta bifurcates into
left and right common iliac arteries
at L4
- Common Iliac Arteries bifurcate
into internal and external at L5
- External Iliac artery passes under
the inguinal ligament to form the
femoral artery
- Internal Iliac Artery bifurcates into
anterior and posterior divisions at
- Anterior division:
- obturator artery
- umbilical artery -> superior
vesicular
- uterine artery -> vaginal artery
- inferior vesicular -> ductus
deferens
- internal pudendal
- middle rectal
- inferior rectal
- dorsal artery to penis/clitoris
- perineal artery
- transverse perineal artery
- posterior scrotal/labial artery
the umbilical artery is a medial umbilical remnant
inferior vesicular artery only present in males
internal pudendal is terminal artery of the internal iliac artery
54
Divisions of the Anterior Iliac Artery:
insert diagram
55
What is the terminal branch of the anterior division of the internal iliac artery and what does it supply?
- internal pudendal artery
- perineum
56
Anterior Division of Internal Iliac Artery
insert diagram
57
Anterior division of the internal iliac artery
insert diagram
58
What are the branches of the internal pudendal artery?
- inferior rectal artery
- dorsal artery of clitoris/penis
- perineal artery which gives off
transverse perineal and posterior
labial/scrotal artery
59
Inferior Pudendal Artery Branches
insert diagram
60
Venous Drainage of the Perinea:
- drain into plexus and named veins
- vesical venous plexus
- vaginal venous plexus
- uterine venous plexus
- prostatic venous plexus
- rectal venous plexus
- all drain into the internal iliac vein
- which drains into the inferior vena
cava at L5
61
Venous Drainage of the Perineum:
insert diagram
62
Drainage of the Gonads:
- right testis drains into the IVC
- left testis drains into the left renal
vein
63
Somatic Nerves of the Pelvis:
- obturator nerve L2-4
- does not supply anything in
perineum
- travels down lateral wall of the
pelvis
- lumbrosacral trunk L4-5
- sacral plexus: arises on the
internal/anterior surface of the
piriformis muscle
- contributions from L4
64
Somatic Nerves of the Pelvis:
insert diagram
65
Sacral Plexus:
insert slide
66
Sacral Plexus:
insert diagram
67
Autonomic Nerves of the Pelvis:
- hypogastric (SNS and visceral
afferents) T11/12-L2
arises from the superior hypogastric plexus -> most inferior plexus in abdo cavity
- pelvis splanchnic (PNS) S2-4
- inferior hypogastric plexus (ANS
and visceral afferents)
68
Autonomic Nerves of the Pelvis:
insert diagram
69
Perineal Innervation:
- genital branch of genitofemoral
(somatic) L1-2 -> cremaster muscle
- ilio-inguinal nerve (somatic) L1
- Pudendal Nerve (somatic): S2-4:
- inferior rectal
- dorsal nerve of clitoris/penis
- perineal nerve
Main motor and sensory supply = pudendal nerve
70
Perineal Innervetion:
insert diagram
71
What is the main motor and sensory supply to the perineum?
pudendal nerve
72
Pudendal Nerve Pathway:
insert diagram
- exit pelvis through greater sciatic
foramen
- loop around to ischial spine to re-
enter into the perineum
- through lesser sciatic foramen
- passes through pudendal canal to
give inferior rectal nerve
- branches into the dorsal nerve of
penis or clitoris when emerging
- and perineal nerve which branches
into posterior scrotal/labial and
transverse muscular branches
- surgery: anesthise pudendal nerve
73
Perineal innervation:
insert slide
