Urogenital triangle Flashcards
what forms the boundaries of the urogenital triangle
imaginary line between the ischial tuberosities (base) and the apex of the triangle at the pubic symphysis
the urogenital diaphragm is found in the urogenital triangle - what structures must pass through this in both sexes
urethra
scarpa’s fascia is called what as it passes into the labia/scrotum
colles’ fascia
colles’ fascia attaches where
posterior border of the urogenital diaphragm at a small dense piece of connective tissue called the perineal body
what is the fatty fascia of the abdominal wall called
camper’s
what is campers fascia continuous with
ischiorectal fossa and thigh
in the scrotum, campers fascia is replaced with what
dartos smooth muscle
where is the urogenital diaphragm found
fills the urogenital triangle - closes off the space between the pubic bones
what is the function of the urogenital diaphragm
prevents structures passing out of the pelvic cavity (prolapse) and provides an area of attachment for structures of the superficial perineal pouch
how many layers is the urogenital diaphragm
3 layers
what is the superior (deep) layer of the urogenital diaphragm composed of
fascia that blends with the perineal body and membrane
describe the middle layer of the urogenital diaphragm
contains the voluntary sphincter that controls urination - sphincter urethrae, and deep transverse perineal muscles
the middle layer of the urogenital diaphragm is also described as containing an anatomical space called the
deep perineal pouch
describe the inferior (superficial) layer of the urogenital diaphragm
the perineal membrane
structures that lie between the perineal membrane and the skin are described as being where
in the superficial perineal pouch
the deep perineal pouch lies where
between the fascial layers of the urogenital diaphragm
what happens to the fascial layers of the urogenital diaphragm anteriorly
fuse, leaving a small gap near pubic symphysis
anteriorly, the fascial layers of the urogenital diaphragm fuse leaving a small gap near pubic symphysis - what passes through this gap
vessels to the clitoris and penis
what happens to the fascial layers of the urogenital diaphragm posteriorly
layers fuse with the perineal body
the fusing of the fasical layers of the urogenital diaphragm posteriorly with the perineal body helps to do what
helps to connect the fascia of the urogenital diaphragm to the rest of the fascia in the pelvis and is involved in the transmission of stress across the pelvic floor
posteriorly the fascial layers of the urogenital diaphragm fuse with what
eachother, membranous superficial fascia and the perineal body
structures that need to pass from the pelvic cavity to the perineum must pass through the urogenital diaphragm and therefore the middle layer of the diaphragm the ___
deep perineal pouch
what passes through the deep perineal pouch in both sexes
urethra
branches of the internal pudendal artery and pudendal nerve
what passes through the deep perineal pouch only in males
small bulbourethral glands that add fluid to the urethra
membranous urethra
penile arteries
dorsal nerves of penis
what passes through the deep perineal pouch only in females
the vagina
dorsal nerves of clitoris
where do small glands associated with the vagina lie in the female
in the superficial perineal pouch
what is found in the deep perineal pouch
urethra
sphincter urethrae
deep transverse perineal muscles
internal pudendal vessels and branches
pudendal (perineal) nerve
where is the superficial perineal pouch
between the perineal membrane and the skin
what is found in the superficial perineal pouch
reproductive structures of the perineum in both sexes
what are the contents of the superficial perineal pouch
small muscles, pieces of erectile tissue, nerves and vessels that supply them and the urethra
what is the erectile tissue found in the superficial perineal pouch
crura
bulb of vestibule (female)
bulb of penis (male)
what muscles are found in the superficial perineal pouch
ischiocavernosus
bulbospongiosus
superficial transverse perineal
what nerves supply ischiocavernosus and bulbospongiosus
perineal branches of the pudendal nerve
ischiocavernosus and bulbospongiosus are
small skeletal muscles
ischiocavernosus and bulbospongiosus lie over
erectile tissues of the perineum in box sexes
how do ischiocavernosus and bulbospongiosus help to maintain erection
contract to impede venous return - retaining the blood inside the erectile tissue
ischiocavernosus overlie
crura
bulbospongiosus overlies
bulb of the penis in males and bulb of vestibule in females
describe how bulbospongiosus differs between males and femlaes
males: bulbospongiosus muscles meet in the midline and surround the bulb of the penis
females bulb of vestibule is in two parts one on either side of opening to vagina - over vestibule
what muscles support the edge of the urogenital triangle in both sexes
the superficial transverse perineal muscles
what is the equivalent of the superficial transverse perineal muscles in the deep pouch
deep transverse perineal muscles
what structure sits at the posterior edge of the urogenital diaphragm
perineal body
what does the perineal body provide attachment for
EAS
bulbospongiosus
superficial transverse perineal muscles
erectile tissues are ____ in females
smaller
what is the erectile tissue lying next to the ischiopubic rami
crura (Singular crus)
in females the crura continue to form what
clitoris
in males the crura continue to form what
corpora cavernosa
in males the bulb of the penis continues to form what
corpus spongiosum of the penis
the corpus spongiosum will also form what
glans penis
the bulb of the vestibule surrounds the
opening of the vagina
the bulb of the vestibule continues to form what
glans of the clitoris
what are the erectile tissues of the penis
2 corpus cavernosum
1 corpus spongisum
the urethra lies within what
corpus spongiosum (spongy/penile urethra)
what is the erectile tissue of the penis supported by
surrounded by connective tissue that contains the vessels and nerves that supply the erectile tissue and skin
what arteries supply the penis
branches of the internal pudendal artery - scrotal artery and transverse perineal artery
deeper vessels to the bulb and erectile tissues are also branches of internal pudendal - deep artery of penis, dorsal artery of penis, artery of bulb
what nerves supply the penis
sensory branches of the pudendal nerve
erectile tissue is innervated by ANS
describe the female urethra
only a few cm long and passes from the trigone of the bladder through the deep perineal pouch and opens in the superficial perineal pouch
why are females more prone to UTI
straight muscular tube and short length and uncomplicated pathway
how many parts does the male urethra have
4
what are the 4 parts of the male urethra
pre-prostatic
prostatic
membranous
penile (spongy)
describe the pre-prostatic urethra
short between the trigone and the prostate gland
describe the prostatic urethra
passes through the prostate gland and is joined by the ejaculatory ducts
describe the membranous urethra
passes through the urogenital diaphragm
describe the penile or spongy urethra
passes through the corpus spongiosum to open at the glans of the penis
what is the narrowest part of the male urethra
membranous
why is the membranous urethra the narrowest
slightly compressed as it passes through the layers of the urogenital diaphragm
when might the membranous part not be the narrowest
usually is in healthy people but if prostatic enlargement then the prostatic part will be the narrowest
branches of what nerve supply sensory innervation to the penis and scrotum
pudendal nerve branches
the perineal branches of the pudendal nerve also contain what
motor fibres to the small muscles in the superficial perineal pouch
what notch does the pudendal nerve pass through
greater and lesser sciatic notches
describe the path of the pudendal nerve
passes through the greater sciatic notch, around the ischial spine and through the lesser sciatic notch
what is the clitoris formed from
erectile tissue derived from the crura and the bulb of the vestibule
the erectile tissue of the clitoris is also supplied by the
ANS
the blood supply of the clitoris is from
branches of the internal pudendal artery
sensory nerve supply of the clitoris is from
branches of the pudendal nerve