Pelvis Flashcards
what’s the differences between the male and female bony pelvis?
pelvis major and minor: F = shallow and wider, M = deep and narrower
pelvic inlet: F = oval/round, M = heart shaped
sub pubic angle: F > 90, M < 90
Acetabulum: F = smaller
Obturator foramen: F = round, M = oval
what are the 2 joints associated with the pelvis and what type of joints are they?
sacroiliac joint = synovial plane
pubic symphysis = secondary cartillagenous
what nerves lie on the piriformis?
sacral plexus
what are the pelvic floor muscles?
puborectalis
pubococcygeus
illiococcygeus
coccygeus
give 2 functions of the pelvic floor.
constrictor/continence mechanism for urethra, anus and vagina
supports abdominal viscera
what is the innervation of the pelvic floor muscles?
levator ani - inferior anal nerve S4, coccygeal plexus
coccygeus - anterior rami of S4 and S5
what is a cytocele?
prolapse of bladder into vagina
what is a retrocele?
prolapse of rectum into vagina
why is damage to the pelvic floor during childbirth damaging?
stretching or tearing of the perineal body from th perineal muscles can cause prolapse of the uterus/vagina or bladder
what can be done in order to avoid damaging the pelvic floor muscles during childbirth if the birth canal is too narrow?
episiotomy
this will enlarge the vagina to minimise damage to the perineal body and perineal muscles
what is more preferred, a midline or mediolateral episiotomy and why?
mediolateral episiotomy will prevent tearing of the peroneal body which is in the midline and therefore going through ligaments
because going through ligaments causes less bleeding but longer to heal compared with cutting through muscle which will heal quicker
what is the main blood supply of the pelvic organs?
internal iliac arteries
what artery supplies the testes and ovaries?
gonadal artery
what is the blood supply of the bladder?
superior and inferior vesical arteries
what artery supplies the vagina?
vaginal artery
what is the main blood supply of the perineum?
internal pudendal artery
what does the obturator artery supply?
muscles of the pelvic floor
nutrient artery to illium and femur
what is the blood supply of the seminal vesical and prostate in males?
superior and inferior vesical
what parts of the rectum drain into the portal and systemic circulation ?
superior 1/3 = portal circulation
inferior 2/3 = systemic circulation
what is the importance of knowing the venous drainage of the rectum?
the superior 1/3 drains into the portal circulation os can be affected by portal hypertension
why might haemorrhoids be associated with cirrhosis of the liver?
cirrhosis = portal hypertension
increased venous pressure can cause haemorrhoids
what is the course of the pudendal nerve?
formed from the sacral plexus
travels through the lower part of the greater sciatic foramen and goes to supply the perineum
follows with pudendal artery
what foramen does the pudendal nerve go through and what does it supply?
greater sciatic foramen
perineum
what is the root values of the pudendal nerve?
S2 - S4
what procedure is used to reduce/stop pain during childbirth and why?
bilateral pudendal nerve block
pudendal nerve supplies the skin and muscles of the perineum
what bony landmark is used when performing a bilateral pudendal nerve block?
ischial spine
what does the pudendal nerve innervate?
muscles and skin of the perineum
what pelvic area does the external iliac lymph nodes drain?
superior parts of anterior organs
what pelvic area does the internal iliac lymph nodes drain?
gluteal region, deep perineum, inferior pelvic viscera
what pelvic area does the sacral lymph nodes drain?
posterior inferior pelvic viscera
where does the 3 lymph node groups in the pelvis drain?
drain to the common iliac lymph nodes
what are the 3 main lymph groups in the pelvis?
internal iliac
external iliac
sacral
what is the innervation of the coccygeus muscle?
anterior rami S4 and S5
