Anatomy of Pelvis Flashcards
What artery is the main supply for the pelvic organs and perineum?
Internal iliac artery
Where do the pubis, ilium and ischium all meet?
Acetabulum
Where on the obturator membrane is the obturator canal which allows passage of neurovascular bundle?
Anterior superior aspect of obturator membrane
The lateral aspect of the levator ani is attached to what?
Tendinous arch of levator ani
The tendinous arch of levator ani is thickened fascia from which muscle?
Obturator internus muscle
The tendon of which muscle passes through the lesser sciatic foramen?
Obturator internus
The tendon of which muscle passes through the greater sciatic foramen?
Piriformis
The piriformis is a landmark for what two nerves?
Is where gluteal nerve divides into superior and inferior and is also where sciatic nerve usually emerges inferior
What are the two exceptions of the pelvic wall arteries that don’t arise from the internal iliac artery?
Gonadal artery (from abdo aorta at L2) and superior rectal artery (continuation of inferior mesenteric artery)
The anterior division of the internal iliac artery is usually ______ and the posterior division is usually ______ in terms of the structures it supplies.
Anterior division is visceral and posterior division is parietal so body wall
The medial umbilical ligament is a remnant of _______ which connected the ______ to the placenta through the umbilical cord.
remnant of umbilical artery which connected the internal iliac artery to the placenta
What is a common variation of the gluteal arteries in relation to the posterior and anterior division of internal iliac artery?
Usually superior and gluteal arteries arise from posterior division on internal iliac however common variation is that inferior arises from anterior division
List 6 important arteries that branch from the anterior division of internal iliac artery in female pelvis
superior vesical arteries, obturator artery, uterine artery and vaginal artery (branch from uterine), internal pudendal artery, middle rectal artery
In the male pelvis what artery is homologous to the uterine artery in the female?
Artery to the vas deferens
In the male pelvis what artery is there instead of vaginal artery?
Inferior vesical arteries - in females the vaginal artery gives off inferior vesical arteries so don’t need own one
What are two important arterial anastamosis in the female pelvis?
Between uterine and vaginal artery at around cervix and vaginal wall and between uterine and ovarian artery
Caution must be taken in hysterectomy to not damage which structure and why?
Ureter - water under the bridge because it crosses underneath the uterine artery
What is vermiculation of ureter?
Ureter wiggles when you touch it so can differentiate it from arteries in surgery
Iatrogenic damage to the ureter in females is more likely on which side? And why?
More likely on left side than right because left passes more medially
List 3 (4) branches of the internal pudendal artery in females?
Inferior rectal artery, dorsal artery of clitoris, perineal artery which branch into labial arteries,
There is contribution from which artery to the perineum?
External iliac artery contributes
What branches do the inferior vesical arteries give off in the males? (2)
Artery to vas deferens and prostatic branch of inferior vesical artery
What are 4 important branches of the internal pudendal artery in males?
Perineal artery, posterior scrotal artery, deep artery of penis and then dorsal artery of penis (this is the termination of internal pudendal)
The anterior scrotal artery branches from what?
External iliac artery
The venous drainage of the pelvis often follows the arterial system. What does it mainly drain into?
Internal iliac vein
Other than internal iliac vein, list 2 other venous drainage sites and explain why they are clinically relevant?
Some will drain via superior rectal into hepatic portal system and some will drain via lateral sacral veins into internal vertebral venous plexus. Clinically relevant because provides alternate collateral pathway to superior or inferior vena cava and metastasis e.g. ovarian or prostatic cancer route to vertebral or cranial sites
List 6 important nerves that lie on the lateral wall of the pelvis.
Obturator nerve (passes through), lumbosacral trunk, sciatic nerve, pudendal nerve, nerve to levator ani and pelvic splanchnic nerves
What muscles does the sacral plexus of the lateral wall sit on?
Piriformis and coccygeus
What is the route of the pudendal nerve?
S2,S3,S4 then goes out greater sciatic foramen, then loops around sacrospinous ligament and comes back into perineum via lesser sciatic foramen
Nerve to levator ani is S ?
S3 S4
Lumbosacral trunk contributes to ?
Sacral plexus
Pelvic splanchnic nerves come from S?
S2, S3 and S4 anterior rami
What is the pelvic splanchnic nerves modality?
Parasympathetic innervation
Generally, the superior portion of pelvic viscera drain lymph where?
Into external iliac nodes -> common iliac -> aortic -> thoracic duct -> venous system
Generally, the inferior portion of pelvic viscera and deep perineum drain lymph where?
Into internal iliac nodes -> common iliac -> aortic -> thoracic duct -> venous system
Generally, where does superficial perineum drain lymph?
Superficial inguinal nodes
Where do ovaries and testes generally drain lymph to and why?
Lumbar lymph nodes - aortic AKA caval because they originated on posterior abdominal wall
What is trans-peritoneal spread?
Disease can penetrate through the peritoneal layer and disseminate into peritoneal cavity
