Pelvic Vessels and Nerves PDF

Pelvic Vessels and Nerves DPM PROGRAM 1. Describe the somatic innervation to pelvic structures. 2. Describe the vasculature of the urogenital system and suprarenal glands. 3. Describe the branches of the internal iliac artery. 4. Describe the venous drainage of the internal iliac vein. 5. Describe...

Pelvic Vessels and Nerves DPM PROGRAM 1. Describe the somatic innervation to pelvic structures. 2. Describe the vasculature of the urogenital system and suprarenal glands. 3. Describe the branches of the internal iliac artery. 4. Describe the venous drainage of the internal iliac vein. 5. Describe blood supply and lymphatic drainage to the bladder. 6. Describe bloody supply and lymphatic drainage to the rectum and anal canal. 1 SMU - Internal Data Overview of blood supply. Blood supply to the pelvis and perineum comes primarily from branches of the internal iliac artery. Abdominal aorta Common iliac a. INTERNAL ILIAC A. External iliac a. 2 SMU - Internal Data Describe the somatic innervation to pelvic structures. Somatic innervation of pelvic and perineal structures comes primarily from branches off the lumbosacral plexus (ventral rami of L1-S4) Lumbosacral trunk S1 S2 S3 S4 3 SMU - Internal Data Describe the vasculature of the urogenital system and suprarenal glands. ARTERIAL SUPPLY: ABDOMINAL AORTA: Suprarenal Gland: superior suprarenal arteries (branch off inferior phrenic) Middle suprarenal arteries (branch off abdominal aorta) Inferior suprarenal arteries (branch off renal arteries) Renal arteries – arise from the abdominal aorta at L1/L2 vertebral level – supply the kidneys - Give off the inferior suprarenal artery - Give off a ureteric a. Ureters – branches off: renal, abdominal aorta, gonadal & internal iliac arteries) Ovarian a. - paired arteries off the abdominal aorta, supply ovaries and fundus of uterus (anastomoses with uterine and vaginal aa) IMA - Superior rectal a. - unpaired a. off the IMA to the rectum (and upper anal canal) Median Sacral a. - unpaired artery off the distal aorta (anastomoses with lateral sacral and iliolumbar aa.) L4 - Aorta bifurcates into common iliac arteries L5/S1 - Common iliacs divide into internal and external iliac aa. COMMON ILIAC ARTERY: EXTERNAL ILIAC ARTERY: External pudendal a. - branch of the femoral a.; supplies some skin of the perineum (aberrant obturator a.- if obturator a. comes off the inferior epigastric a.) INTERNAL ILIAC ARTERY- MAJORITY OF BLOOD TO PELVIS & PERINEUM Note: gender differences in the branches of the internal iliac artery: males have an Inferior vesical artery; females have uterine and vaginal arteries) 4 SMU - Internal Data Overview of blood supply. Blood supply to the pelvis and perineum comes primarily from branches of the internal iliac artery. Abdominal aorta Common iliac a. INTERNAL ILIAC A. External iliac a. 5 SMU - Internal Data Describe the branches of the internal iliac artery. PARIETAL BRANCHES: • Branches to the Lower Limb: • Superior Gluteal a. (through greater sciatic foramen superior to piriformis m.) • Inferior gluteal a. (through greater sciatic foramen inferior to piriformis m.) • Obturator a. (Through obturator canal to medial compartment of thigh; may come from inferior epigastric a.) • Branches to the abdomen, pelvis & perineum: • Iliolumbar: • - usually first branch off posterior aspect of Internal iliac a. • - ascends to supply iliacus, psoas major & quadratus lumborum • Lateral Sacral (often multiple): • - descends on anterior aspect of sacrum to supply piriformis and the ventral rami VISCERAL BRANCHES: • Umbilical a.: originally patent then becomes ligamentous after giving off superior vesical aa. Becomes the medial umbilical ligament on the anterior abdominal wall • Superior vesical aa. (to superior aspect of bladder) • Inferior Vesical a.: To inferior aspect of bladder and male internal genitalia (males only) • Middle Rectal a.: to anal canal • Vaginal a.: To vagina and inferior aspect of bladder (females only, homologue to inf. vesical a.) • Uterine a.: to uterus (females only) • Internal pudendal a.: to the perineum (exits pelvis through greater sciatic foramen, enters perineum through lesser sciatic foramen, travels in pudendal canal with pudendal n.) • inferior rectal a. to anal canal (to anal triangle) • Urogenital Branches to superficial and deep perineal pouches (in urogenital triangle) 6 SMU - Internal Data Internal iliac artery: parietal branches. Iliolumbar a. (to posterior abdominal wall) Common iliac a. External Iliac a. Superior gluteal a. (to gluteal region) Inferior gluteal a. (to gluteal region) INTERNAL ILIAC a. Lateral sacral a. (to posterior pelvic wall, sacral spinal nerves) Obturator a. (to medial thigh) 7 SMU - Internal Data Internal iliac artery: Visceral branches FEMALE MALE INTERNAL ILIAC a. Internal pudendal a. (to perineum) Umbilical a. Umbilical a. Superior vesical aa. Internal pudendal a. (to perineum) Middle rectal a. Inferior vesical a. Middle rectal a. Uterine a. Vaginal a. 8 SMU - Internal Data Describe the venous drainage of the internal iliac vein. FEMALE MALE (Communicate with internal vertebral venous plexus) (Communicate with internal vertebral venous plexus) VENOUS DRAINAGE: Renal Veins - companion to renal arteries (Left renal vein also receives the left gonadal vein and the left inferior phrenic v) Venous plexuses (interjoining veins surrounding pelvic viscera): Rectal, vesical, prostatic, uterine & vaginal venous plexi Vessels within these plexi unite to form veins that travel with similarly named arteries and drain into the INTERNAL ILIAC VEINS There are many communications between each of these plexi (lots of anastomoses) SMU - Internal Data L5/S1 - Internal and External iliac vv. unite to form the Common iliac vein L4/L5 - union of common iliac veins into IVC 9 Describe blood supply and lymphatic drainage to the bladder. MALE FEMALE Superior vesical aa. Superior vesical aa. Inferior vesical a. (supplies parts of bladder and ureters as well as the seminal vesical, prostate and ductus deferens) Vaginal a. (usually gives branches to the inferior aspect of the female bladder) -Primary blood supply is from the superior vesical arteries (off the umbilical a.). The posteroinferior aspect of the bladder receives blood from the inferior vesical a. in males and the vaginal a. in females. -Venous drainage is via the vesical plexus which drains to the internal iliac v. or internal vertebral plexus (via the lateral sacral v.) -Lymph from the bladder goes primarily to the internal iliac nodes, however, some lymph from superolateral aspect travels to the external iliac nodes SMU - Internal Data 10 Describe bloody supply and lymphatic drainage to the rectum and anal canal. Anorectal junction - located at superior edge of pelvic diaphragm which also corresponds to the superior edge of the anal columns. BLOOD SUPPLY: Superior rectal a./v. - from/to IMA/IMV (portal) (terminate inside the anal columns, supplies region above pectinate line) Middle rectal a./v. - from/to Internal iliac a./v. (caval) (anastomose with both superior and inferior rectal vessels) Inferior rectal a./v. - from/to Internal pudendal a./v. (caval) (supplies region below pectinate line) LYMPHATIC DRAINAGE: Inferior anal lymph drains to the superficial inguinal nodes More superior anal lymph drains deeply to the internal iliac nodes Rectum (and superior 2/3 of the anal canal) drains to the Inferior mesenteric nodes and the intestinal trunk 11 SMU - Internal Data