Introduction to Pelvis and Perineum Flashcards
Which part of the pelvis is termed as the true pelvis
Inferiorly
Which part of the pelvis is termed as the false pelvis
Superiorly
What type of joint is the sacroiliac joint
Synovial
What type of joint is the pubic symphysis
Secondary cartilaginous (a joint made of hyaline cartilage and fibrocartilage)
Describe the male and female greater pelvis
Female-shallow
Male-deep
Describe the male and female lesser pelvis
Female-Wide and shallow
Male- narrow and deep
Describe the male and female pelvic inlet
Male-oval and round
Female-heart shaped
Describe the male and female pelvic outlet
Male-small
Female- large
Describe the obturator foramen in male and female
Female-oval
Male-Round
What is the narrowest diameter of the pelvic inlet
13cm
What is the narrowest diameter of the pelvic outlet
11cm
What muscle is present in the posterior wall of the pelvis
Piriforms
Which nerve network lies on the muesli forming the posterior wall of the pelvis
Sacral plexus
Where does the Perineal body lie?
Midline of the perineum anterior to rectum and anal canal
Where does the anococcygeal body lie?
Midline between coccyx and posterior part of rectum
Name the muscles that make up the majority of the pelvic floor
Levator Ani
Coccygeus
Name 2 functions of the pelvic diaphragm/floor
Helps support pelvic viscera
Resists increases in intra-abdominal pressure
What is the innervation of the pelvic diaphragm
Branches of S4
Inferior anal (rectal) nerve
Coccygeal plexus
What is Cyctocele
Prolapsed bladder
What is Rectocele
Herniation of the front wall of the rectum into the back wall of the vagina
Injury to pelvic floor during childbirth is common and potentially damaging.
Why?
During childbirth the pelvic floor supports the foetal head while the cervix of the uterus is dilating to permit delivery of the foetus
Why may an episiotomy minimise long term damage?
It can help prevent severe spontaneous tears
Whys is a mediolateral episiotomy preferable to a midline episiotomy
Risk of anal tear is much lower
List the 3 main urinary pelvic organs
Bladder
Ureter
Urethra
List the main male reproductive pelvic organs
Testes Epididymis Prostate Ductus deferens Seminal glands Ejaculatory ducts Bulbourethral glands
List the main female reproductive pelvic organs
Vagia
Uterus
Uterine Tubes
Ovaries
What structures can be palpated when performing a DRE
Prostate
Uterus and Cervix
What arteries supply the bladder, seminal gland and prostate in males
Superior and inferior vesical artery
What arteries supply the pelvic part of the ureter, uterus, ligament of uterus, uterine tube and vagina
Uterine artery
What arteries supply the abdominal artery from the pelvis
Gonadal (testicular or ovarian)
What artery ripples the Gluteal muscles and tensor fasciae latae
Superior rectal artery
What artery supplies the seminal gland, prostate and rectum
Middle and inferior rectal artery
What artery supples the Vagina and branches to inferior part of urinary bladder
Vaginal artery
What artery supplies the perineum
Internal pudendal artery
What artery supples the pelvic muscles
Obturator artery
Which part(s) of the rectum drain(s) into the portal circulation?
Superior rectal veins
Which part(s) of the rectum drain(s) into the systemic circulation?
Middle and Inferior rectal veins
What is the significance of understanding the venous drainage of the rectum?
The venous drainage of the rectum mirrors the arterial supply
Why might haemorrhoids be associated with cirrhosis of the liver?
The upper and middle thirds of the rectum drain primarily into the superior rectal vein and finally empty into the liver via the inferior mesenteric vein and portal vein
With which venous plexus does the prostatic venous plexus communicate with on its posterior side?
Internal vertebral venous plexus
Where does the ilioguinal nerve originate from and what does it supply
L1
Skin at root of penis in male and labia in female
Where does the genitofemoral nerve originate from
L1 and L2 and enters deep inguinal ring
Which segmental level does the pudendal nerve arise from
S2-S4
What bony landmarks are used when performing a pudendal nerve block during labour
The sacrospinous ligament to the ischial spine
Where does the autonomic nerve supply to the pelvis originate
Pelvic Plexus
Where do the sympathetic fibres originate
L1 and L2 via the hypogastric nerve and terminal aspect of the sympathetic trunk
Where do the parasympathetic fibres in the pelvis originate from
Pelvic splanchnic nerves (S2 to S4)
What are 4 primary lymph node groups in the pelvis
External iliac
Internal iliac
Sacral
Common iliac
