Repro Anatomy 4 Flashcards
The perineum lies inferior to the pelvic diaphragm and is the most inferior portion of the trunk. It can be divided into two triangular areas.
What bony landmarks create the boundaries of the perineum?
A?
Pubic symphysis
The perineum lies inferior to the pelvic diaphragm and is the most inferior portion of the trunk. It can be divided into two triangular areas.
What bony landmarks create the boundaries of the perineum?
B?
Ischial tuberosities, ischiopubic rami and sacrotuberous ligament
The perineum lies inferior to the pelvic diaphragm and is the most inferior portion of the trunk. It can be divided into two triangular areas.
What bony landmarks create the boundaries of the perineum?
C?
Tip of coccyx
Which triangle is shown by the shaded orange area above?
Which triangle is shown by the shaded green area above?
orange = urogenital triangle
green = anal triangle
Which bony prominences separate each of the triangles?
ischial tuberosities
A thin sheet of deep fascia stretches between right and left sides of the pubic arch, below the pubic symphysis.
What is the name given to this fascia?
pelvic fascia
Support to the organs of the perineum is provided by the _______ of the perineum and ______ planes – there are some anatomical variations between the male and female perineal muscles, these will be highlighted through this section
muscles
fascial
what supplies the msucles of the perineum?
Branches of Pudendal Nerve
(S2 to S4)
muscle - External anal sphincter
what is its main action?
Voluntary sphincter to control bowel movements
muscle - Superficial transverse perineal
what is its main action?
Fixes and stabilizes the perineal body
muscle - Deep transverse perineal
what is its main action?
Forms urogenital diaphragm and anchors the perineal body, thus supporting the pelvic viscera, compress uretha to maintain urinary continence
muscle - External urethral sphincter
what is its main action?
Compress urethra to maintain urinary continence
muscle - Bulbospongiosus (Male)
what is its main action?
Relaxed when peeing but contacts to stop urine flow. Aids in fully emptying the urethra after urination. Contacts rhythmically during ejaculation to create a series of wave-like contractions within the corpus spongiosum, this facilitates movement of ejaculate through urethra, constrictions veins in bulb of penis to maintain erection
muscle - Bulbospongiosus (Female)
what is its main action?
Contributes to clitoral erection and the contraction of orgasm, and closes the vagina. Serves to empty the canal of the urethra after the bladder has expelled its contents, its relaxed during peeing and only contracts at the end
muscle - Ischiocavernosus (Male)
what is its main action?
Help impeding venous return from corpora cavernosa of the penis, aiding in maintenance of erection. Rhythmic contraction with bulbospongiosus during ejaculation. Contraction help maintain erection and possibly aid moving ejaculate through urethra
muscle - Ischiocavernosus (Female)
what is its main action?
Pushes blood from root of clitoris to body i.e. maintains erection of clitoris, tenseness vagina during orgasm
What are the potential consequences if the perineal body is damaged/ruptured during childbirth?
prolapse of pelvic viscera
There are 2 layers of fascia important as additional support for the pelvic organs within the perineum
These are the _______ and _______ fascia, making up the pelvic diaphragm
superior
inferior
Which structures pierce through the pelvic diaphragm?
urethra
anal canal
is the urethra longer in males and females and why?
The urethra is longer in males compared to females due the number of structures it has to traverse
A
Rectum
B
Preprostatic part of urethra
C
Prostatic urethra
D
Urethra – external sphincter, membranous part of urethra
E
Corpus spongiosum
F
Urinary bladder
G
Pubic symphysis
H
Prostate
I
Spongy part of urethra
J
External urethral meatus
What are the 3 parts of the male urethra?
preprostatic
prostatic
spongy part
Which are the widest and narrowest parts of the male urethra and why?
Widest part = Prostatic – receives ejaculatory ducts and prostatic ducts
Narrowest part = membranous – runs through pelvic floor and is enclosed by the external urethral sphincter
the urethra is at risk of becoming narrowed due to enlargement of what?
the prostate
The male external genitalia comprise of what?
the testes, scrotum and penis
The penis is the male organ of copulation and is the common outlet for both urine and semen
It comprises of the left and right corpus _______ and single corpus _______. The terminal aspect of the penis is the glans penis, covered by the prepuce (foreskin) and provides transit for the urethra via the external urethral meatus.
cavernosa
spongiosum
The corpus cavernosa is covered by a fascial layer called the what?
tunica albuginea
The urethra is transmitted through the corpus….
spongiosum
below the corpus cavernosa and in the middle of corpus spongiosum
he majority of the erectile tissue in the penis is in the corpus…..
cavernosa
Sensory innervation of the penis is through the dorsal nerve of the penis, a branch of the ________ nerve
pudendal
Where is the internal/vesical urethral sphincter located?
proximal end of the urethra at the neck of the bladder
Internal urethral pshincter - Is it voluntary or involuntary? What is its innervation?
involuntary
sympathetic T10-L2
Where is the external urethral sphincter found in females?
deep perineal pouch at distal inferior boarder of bladder
Where is the external urethral sphincter found in males?
surrounds the membranous part of the urethra
extenral urethral sphincter - Is the sphincter voluntary or involuntary? What is its innervation?
voluntary
S2-4
Clinical – Urinary Incontinence:
In both the male and female urinary incontinence can develop due to disruption to one or both of the above.
The aging process ________ the urinary sphincters making incontinence more likely, however other factors can contribute to this
In males any form of ______ surgery to overcome urinary retention can make urinary incontinence more likely
In the female ________ can weaken the ligaments supporting the pelvic floor, and can increase the risk of incontinence
prostatic
childbirth
weakens
Female External Genitalia:
The vulva is the collective name for the female external genitalia.
The contents of the vulva are:
- Mons pubis
- Labia majora
- Labia minora
- Vestibule
- Bartholins gland
- Clitoris
These structures are collective supplied by the pudendal nerve, and internal pudendal artery
The vestibule is the area enclosed by the _____ minora and contains the terminal aspects of the ______ and ______
labia
vagina
urethra
what is the clitoris?
Mirroring the corpus cavernosa in the male, the clitoris is the erectile tissue found within the female external genitalia
It is comprised of 2 crura, which meet in the midline to form the body. This then projects downwards to the prepuce and glans which lies in the anterior labial commissure
There is no equivalent of the corpus spongiosum in females
what is the anal triangle and what does it contain?
The anal triangle is the area between the ischial spines and coccyx (see the green triangle on page 1). It contains the terminal part of the gastro-intestinal tract, the anus.
The anus runs from the rectum to the external environment and is approx. 4cm long.
There are 2 sphincters controlling defaecation
The internal sphincter under ________ control and the external sphincter under _________ control.
Somatic sensation extends upwards from the external environment to the inter-sphincteric groove (the ‘white line’)
involuntary
voluntary
Lateral to the anal canal and inferior to the pelvic floor are 2 fat containing fossa called the _______________. These allow the anal canal to expand during defaecation.
A
Rectum
B
Obturator internus
C
Iliococcygeus, Pubococcygeus and puborectalis
D
External anal sphincter
E
Anus/Anal canal
F
Obturator fascia
G
Pudendal canal
H
Ischio-anal fossa
A neurovascular bundle enters the ischio-anal (rectal) fossae through the lesser sciatic foramen.
What structures are present in this bundle?
What structures do these neurovascular structures supply?
internal pudendal artery
internal pudendal vein
pudendal nerve
external genitalia
external genitalia
skin of external genitalia and skin around anus
