35,36: Pelvis

Front 1

describe the greater pelvis

Back 1

area from the iliac crest to the pelvic floor

Front 2

describe the lesser pelvis

Back 2

region of greater pelvis

from promentory/pubic symphysis to pelvic floor

Front 3

what are the major boney components of the pelvis

Back 3

iliac crest

iliac fossa/ala

pubis

ischium

greater/lesser sciatic notch

anterior superior/inferior iliac spine

coccyx

obturator foramen

promentory-- sacrum/L5

pubic symphysis

pectineal line-- arcuate line

Front 4

what are the differences between male and female pelvises

Back 4

male: heavier build, deeper interior and conical in shape, heart shaped inlet, subpubic angle of 50-60 degrees, sharper coccyx and ischial spines

female: interior is cylindrical, circular inlet, subpubic angle of 80-85 degrees

Front 5

describe the linea terminalis

Back 5

inlet of lesser pelvis

pubic crest, pecten pubis (pectineal line), arcuate line, margin of ala, promentory

Front 6

what are the important measurements/distances to know for the pelvis

Back 6

intercrestal distance

interspinous distance (iliac spines)

interspinous distance (ischius spines)

oblique diameter

transverse diameter

obstetrical conjugate (>10cm)

Front 7

what are the 3 different conjugates and which is the most important

Back 7

anatomical (superior pubic symphysis to promentory)

**true (obstetric) (median pubic symphysis to promentory) baby passes here

diagonal (inferior to promentory) can measure here

Front 8

what are the 2 proper orientations for the baby to emerge safely

Back 8

face to anus or face up

largest/safest diameter for head to move through

Front 9

what are the largest diameters through the birth canal

Back 9

inlet: transverse (12cm)

cavity: oblique (12cm)

outlet: sagittal (9.5cm)

like an elbow pipe

coccyx can shift backwards to allow head through-- 12cm

Front 10

what are the major ligaments of the pelvis

Back 10

connecting sacrum to pelvis

iliolumbar ligament

anterior/posterior sacro iliac ligaments

other ligaments (sacrotuberous/sacrospinous etc) create greater/lesser sciatic foramen

like a suspension bridge

Front 11

describe the obturator foramen

Back 11

almost completely filled by obturator membrane which gives attachment to muscles

obturator nerve passes through

Front 12

describe the greater sciatic foramen

Back 12

penetrated by piriformis muscle creating supra and infra piriform hiatus

sciatic nerve runs through

Front 13

describe the floor of the pelvis

Back 13

pelvic diaphragm; levator ani muscle and its fascia

funnel with a beak (anus), hole in anterior side (vagina/urethra)

function: supports pelvic viscera and resists downward thrust from increased abdominal pressure (coughing, defacation, labor, heavy lifting)

Front 14

what are the components of the levator ani muscle

Back 14

puborectalis- median, pubis to coccyx around anus (external anal sphincter) forms urogenital hiatus anteriorly (left and right crus)

central tendon anterior to anus

pubococcygeus- medial, pubis around anus to pubis

iliococcygeus- lateral, attaches to obturator internus muscle with tendinous arch of levator ani muscle

Front 15

what are the contents of the female pelvis

Back 15

uterus and ovaries (fallopian tubes, round ligament off fundus)

rectum

bladder

vagina

2 pouches: rectouterine and vesicouterine

pelvic diaphragm (levator ani and superior/inferior fascia)

Front 16

describe ischiorectal fossa

Back 16

mostly fatty tissue and skin below the pelvic diaphragm

triangle in shape, on both sides of vagina/prostate

between ischium and rectum

Front 17

describe paracolpium

Back 17

above pelvic diaphragm surrounding vagina

tissue

Front 18

what are the contents of the male pelvis

Back 18

rectum

bladder

prostate gland (below bladder, surrounds urethra)

seminal vesicles

ampulla of vas deferens

1 pouch: rectovesicle

pelvic diaphragm (levator ani and superior/inferior fascia)

Front 19

describe the urogenital membrane

Back 19

provides support for structures against abdominal pressure in the uruogenital hiatus

forms external sphincter of urethra

Front 20

describe the uterus

Back 20

intraperitoneum

broad ligament of the uterus-- membrane holds uterus in place, attaches to pelvis (parametrium- close to uterus, caudinal ligament- at base, hold vessels, mesosalpinx- broad ligament above ovary, mesovarium- attaches to ovary)

fallopian tubes (isthmus, ampulla, infundibulum, fimbriae)

ligament of ovary

suspensory ligament of ovary with gonadal artery and vein

triangle shaped cavity, isthmus is narrowing, cervix is muscular entrance, protrudes into vaginal canal (creates anterior/posterior pouch)

ovary is naked- no peritoneum (capsule)

Front 21

describe the position of the uterus

Back 21

lays almost horizontal on bladder

angle between body and cervix

angle between cervix and vagina

anteflexed and anteverted position

Front 22

describe uterine prolapse

Back 22

uterus moves down through/out of vagina because of a lack of support from the pelvic floor

Front 23

describe the blood supply to the uterus

Back 23

uterine artery to uterus (from internal iliac/hypogastric artery) in floor of broad ligament

vaginal artery (from internal pudendal artery [from internal iliac])

ovarian artery is special, from abdominal aorta within suspensory ligament, developed higher and descended

Front 24

describe the rectum

Back 24

most posterior component of pelvis

5 inches long, begins at middle sacrum and follows sacral curve

ends 1 inch beyond coccyx bending backwards

external sphincter= levator ani

air-tight closure achieved by columns/sinuses

Front 25

what is the difference between the surgical and the anatomical anal canal

Back 25

surgical canal includes the anal columns and sinuses

anatomical is just below the pectinate line

Front 26

define the ampulla of the anus

Back 26

lower dilated part

Front 27

describe the innervation of the pelvis

Back 27

somatic sacral plexus (superior gluteal, inferior gluteal, sciatic, internal pudendal, posterior femoral cutaneous, pudendal nerves)

inferior hypogastric plexus- mixed nerves

some small sympathetic (off trunk-- sacral splanchnic) and parasympathetic (pelvic splanchnic)

Front 28

describe the blood supply to the pelvis

Back 28

internal iliac artery

visceral and parietal branches

anterior: superior/inferior vesicle, uterine/prostatic, superior rectal

posterior: median sacral, lateral sacral, iliolumbal, superior/inferior gluteal

Front 29

describe the venous drainage of the pelvis

Back 29

accompany arteries but with greater variation

networks and plexi-- named by region

rectal venous plexus etc.

Front 30

describe the blood supply to the rectum

Back 30

superior rectal artery (from inferior mesenteric)

middle rectal artery (from internal iliac)

inferior rectal artery (from internal pudendal)

median sacral artery (from aorta)

Front 31

describe the venous drainage of the rectum

Back 31

mirrors arteries

drains partly to portal system via inferior mesenteric veins

partly to caval system via internal iliac, internal pudendal and median sacral

inferior rectum drains to caval

porto-caval anastomoses (rectal/anal, esophageal, umbilical, retroperitoneal)

Front 32

describe hemorrhoids

Back 32

portal hypertension is one cause

internal: covered by mucous membrane, painless

external: covered by skin, very painful, may prolapse

Front 33

what are classic signs of portal hypertension

Back 33

hemorrhoids

esophageal bleeding

caput medusa (umbilical veins filling, distending)

Front 34

describe the lymphatic drainage of the pelvis

Back 34

follow veins

many lymph nodes

named based on location and association

skin and superficial fascia to superficial nodes

viscera to nodes and lymphatics along deep blood vessels

vagina, urethra, fundus of uterus, and anal canal to superficial inguinal nodes

Front 35

describe endopelvic fascia

Back 35

pelvic viscera lateraly enclosed by fibrous, fatty fascia with is packing and anchoring

visceral nerves and vessels travel through it

thickened sections are named ligaments

female: pubovesical, transverse cervical (cardinal), uterosacral