Anatomy of Pelvis and Perineum Flashcards
What is the function of the bony pelvis?
support of upper body when sitting/standing
transferance of weight from the vertebral column to the femurs to allow standing and walking
attachment for external genitalia and muscles of locomotion and abdominal wall
protection of the pelvic organs, their blood and nerve supplies
At what age do the pubis and ischium fuse?
age 2-8
When does the ilium fuse with the pubis and ischium?
puberty
11-14 women
14-17 men
What makes up the pelvic outlet?
pubic symphysis ischiopubic ramus ischial tuberosities sacrotuberous ligaments coccyx
What makes up the pelvic inlet?
sacral promontory
ilium
superior pubic rams
pubic symphysis
What relaxes during pregnancy?
ligaments of the pelvis
What are the attachments of the sacrospinous ligament?
sacrum -> ischial spine
What are the attachements of the sacrotuberous ligament?
sacrum -> ischial tuberosity
What is the role of the sacrospinous and sacrotuberous ligaments?
stabalisation and ensure the inferior part of the sacrum is not pushed superiorly
What does the presence of the sacrospinous and sacrotuberous ligaments form?
greater and lesser sciatic foramen
What covers the obturator foramen?
obturator membrane
What passes through the obturator foramen?
obturator canal - for obturator nerves and vessels
What is different about a female pelvis compared to a male pelvis?
larger diameter of female pelvis and pelvic outlet and inlet
larger subpubic angle
shallower pelvic cavity
What diameter is wider in the pelvic inlet - transverse or AP?
transverse>AP
What diameter is wider in the pelvic outlet - transverse or AP?
AP>transverse
What allows the babies head to mould in childbirth?
presence of fontanelles and sutures
What are the two fontanelles called?
anterior and posterior
Which fontanelle is bigger?
anterior
What is the vertex?
area of the skull outlined by the anterior and posterior fontanelle and the parietal eminences
What is longer - the biparietal diameter or the occipitofrontal?
occipitalfrontal
What is a fetus’ station?
position in relation to the ischial spines
What does a negative station indicate?
head is superior to the ischial spines
How should the fetal head be at the pelvic inlet?
transverse
How should the fetal head be at the pelvic cavity?
flexed
What makes up the pelvic cavity?
ovaries
uterine tubes
uterus
superior part of the vagina
What makes up the perineum?
inferior part of the vagina perineal muscles bartholins glands clitoris labia
What separates the pelvic cavity and perineum?
levator ani
What are the only intraperitoneal structures?
uterine tubes
What forms the recto-uterine and vesico-uterine pouches?
the perineum
How can the recto-uterine pouch be accessed?
needle through the posterior fornix
What is the role of the broad ligament?
contains the uterine tubes and proximal part of the round ligament
maintains the uterus in its midline position
What is the round ligament?
embryological remnant of the gubernaculum
What is the role of the round ligament?
guides the testis and ovaries from their origin in the posterior wall
Whatre the 3 levels of uterine support?
strong ligaments
endopelvic fascia
muscles of the pelvic floor
What is the normal position of the uterus?
anteverted and anteflexed
What is a normal variation of the uterus?
retroverted and retroflexed
What is a salpingoophrectomy?
removal of uterine tubes and ovaries
can be bilateral = both or unilateral = one
What end of the uterine tubes enter into the peritoneal cavity?
fimbriated end - so infection can transfer between these two areas
What shows whether the uterine tubes are patent or not?
hysterosalphingogram
What are the the fornix of the vagina?
form when the cervix is held open
posterior
anterior
2 lateral
What are the two perineal triangles?
ano-genital and anal
What is the nerve supply to the levator ani?
nerve to the levator ani - S2,3,4
What is the role of the levator ani?
tonic contraction
reflexively contracts more during raised intra abdominal pressure
What nerve supplies the perineal muscles?
pudendual nerve
What is the perineal body?
bundle of collagenous and elastic tissue into which the perineal muscles attach
important for pelvic floor strength - can be distrupted during labour
What are bartholians glands?
secrete mucus for lubrication
can become infected
sit on the labia
