Female Pelvis and Perineum Flashcards
how many and what bones make up the pelvic girdle?
4 bones
* 2 Innominate bones - one on each side. each one is made up of 3 parts (ilium ischium and pubis)
* Sacrum - in the middle
* Coccyx
what level is the tuberculum of illiac crest and clinical relevance?
L5
where drs palpate to insert spinal or epidural block
where does the pelvic inlet and outlet come from? liek where is its landmark?
pelvic inlet = is S1 (sacral promontory) to pubic symphysis
pelvic oulet = is coccyx to pubic symphysis
ASIS and what else are in line with eachother?
pubic tubercle
boundaries of false pelvis and function
posterior = lumbur vertebrae
lateral = illiac fossae and illiacus muscle
anterior = anterior abdomina wall
function - support abdo contents and guides foetus out in childbirth
boundaries of pelvic outlet and is it smooth?
what is its importance
boundaries =
posterior - coccyx
lateral - ischial tuberosities
anterior - pubic arch
not smooth, 3 notches = 2 sciatic notches laterally and pubic arch notch anteriorly
leads to perineum: where external genitalia attach
whats the key ligament that forms the pelvic outlet?
sacrotuberous ligament
what are the main ligaments of the pelvis? (4) and 1 accessory ligament
Anterior Sacroiliac Ligament: Synovial joint to allow a very small amount of movement between the sacrum and the ilium.
Sacro-tuberous ligament and sacro-spinous ligament:
Convert the greater and lesser sciatic notches into greater and lesser sciatic foramina
Posterior Sacroiliac Ligament:
Fibrous tissue. Situated in a deep depression between the sacrum and the Ilium = supports weight of body.
The sacroiliac joint is stabilised by accessory ligaments, such as the ilio-lumbar ligament
Main strength comes from the Posterior sacro-iliac ligament
what structure leaves the pelvis at the lesser sciatic foramen?
What is the only muscle passing through the greater scaitic foramina? what does it do
clinical relevance
obtruator canal: Obturator vein artery and nerve to pass through the obturator canal.
and obturator internus
piriformis muscle
provide support
closely related to the sciatic nerve, arches over the nerve
and landmark for superiro and inferior gluteal nerves
label
Ano-coccygeal ligament:
* A musculo-tendinous structure in the floor of the pelvis
* Extends between the coccyx and the margin of the anus
difference between male and female pelvis
male:
heart shaped
50-60 degrees
female: gynecoid
round shaped
80-85 degrees
label what u can and what is shown?
pelvic diaphragm
The pelvic diaphragm is a wide but thin muscular layer of tissue that forms the inferior border of the abdominopelvic cavity
where does the coccygeus run from? and what does it do
posterior to levator ani
sacrospinous ligament to ischial spine
extends pelvic floor
what is the levator ani and where does it attach
posterior to the pubis
forms pelvic diaphragm/ pelvic floor
seperates pelvic cavity from perineum below
posterior pubis and spine of ischium
- linea thickening over the obturator internus
where does the urethra and vagina pass?
incompleet anterior part of pelvic diaphragm = urogenital hiatus
What attach at the gluteal lines?
there are 3: anterior, inferior and posterior
What is pubic symphysis diastasis?
after traumatic delivery - widening of the pubic symphysis causing dislocation without fracture radiologically more than 10mm
What is sacrospinous fixation?
Women who have had vaginal prolapse has this, where the vagina is hitched up to the SS
what 2 muscles make the pelvic diaphragm? (pelvic floor)
levator ani and coccygeus
What are the 2 divisions of the levator ani?
pubococcygeus (more anterior) and iliococcygeus (posterolateral fibres)
what are the further types of pubococcygeus
what are Pubovaginalis and pubourethralis muscle and where do they insert
What is the pubococcygeus proper muscle?
Function of pubococcygeus proper muscle?
- most medial fibres pass around vagina and urethra (respectively) and insert into perineal body
arises from anterior half of tendinous arch and posterior aspect of the body of pubis (on pelvic surface of iliococcygeus
help to support lower GI and repro tract - important in incontinence
what is perineal body, what muscles are involved?
a fibro-muscular structure located in the midline of the perineum.
prevents prolapse
- ischiocavernosus and bulbocavernosus
What is the puborectalis muscle?
fibres form sling around the rectum - junction between rectum and anal canal: ano-rectal junction
What does the ano-rectal junction allow?
anal angle to be maintained helping in incontinence
What is the innervation to the levator ani muscles?
pudendal nerve (S2 - S4)