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Flashcards in anatomy of the female pelvis Deck (95):
0

What are some external landmarks?

vagina
mons pubis
labia
clitoris
urethral opening
anus

1

what is mons pubis

pad of fatty tissues that overlies the pubis

2

What is the True Pelvis?

Below plevic brim to the pelvic diaphragm, contains pelvic organs

3

what is the false pelvis?

above the pelvic brim to the iliac crest - communicates with abdominal cavity superiorly

4

pelvic cavity

true pelvis, inferior to the caudal portion of the parietal peritoneum

5

what is in the posterior pelvic cavity

rectum, colon and ileum

6

what is in the anterior pelvic cavity

bladder, ureters, ovaries Fallopian tubes, uterus and vagina

7

what is the pouch of douglas

rectouterine space - lowest most posterior portion of the peritoneal cavity

8

what forms the posterior wall?

sacrum and coccyx
margin of post-lat wall formed by piriformis and coccygeus muscles

9

what forms the anterolateral walls?

formed by hip bones and obturator internus muscles

10

what forms the lower margin pelvic cavity?

(aka pelvic floor or pelvic diaphragm)

formed by levator ani and coccygeus muscles

11

muscles of the false pelvis

psoas major muscles - originate at the transverse process of lumbar vertebrae - descend inferiorly on pelvic side walls- join iliacus muscles in false pelvis (they do not enter the true pelvis)

lliopsoas muscle, iliacus and psoas major muscles: descend anterior to hip-insert into lesser trochanter, pass outside pelvic bones , do not enter true pelvis

12

what are the muscles of the true pelvis?

Piriformis muscles -

Obturator internus muscles -

pelvic diaphragm -

levator ani muscle (3 muscle groups) Puboccygeus muscles, lliococcygeus muscles, puborectalis (see the slide)

13

Bladder

location: anterior portion pelvic cavity - posterior to pubic symphysis

Function: Collect and store urine

remains in true pelvis when empty
when distended rises behind lower anterior abdominal wall pushes peritoneum away

14

vagina

extends postero-superiorly at a 45 degree angle from external genitalia to cervix, then forms a 90 degree angle to the cervix

average 9 cm long

anterior to rectum/anus - posterior to bladder/urethra

mucus membrane lining muscular walls

passageway for the products of menstruation

easily distended during sexual intercourse and childbirth
posterior wall is longer than the anterior wall

mucus membrane lining muscular walls

upper half above pelvic floor, lower hald within perineum

arterial supply - vaginal and uterine arteries drain into interal iliac veins

upper portion attaches to cervix -posterior portion attaches higher on cervix

15

what are the fornices?

4 arch like recesses formed by cervix protruding into upper portion of vaginal canal
blind pockets formed by inner surface of vagina and outer surface of cervix
continuous ring shaped space

16

uterus

Müllerian ducts enlogate and fuse to form uterus and vagina between 7th and 12th week of gestation

posterior to bladder/anterior to rectum

hollow, pear shaped

largest organ of female pelvis - allows for cyclic physiologic changes assoc with menstruation and after fertilization, serves to sustain, protect and deliver fetus

3 parts: fundus, body, cervix

usually antiflexed and antverted (held in place by round ligaments)

average size 6-8 cm long and 3-5 cm AP and transverse varies with age and parity

supported by levator ani muscles, cardinal ligaments and uter-sacral ligaments

17

portions of uterus

cervix
isthmus
body of uterus
fundus of uterus
cornua

18

what is the cervix?

"neck of uterus"
lower cylindrical portion of uterus - projects into vaginal canal
muscular
divided into exocervix and endocervix
only portion of uterus firmly supported

19

ithmus

ourter transition point between body of uterus and cervix

"waist" of uterus

point where uterus bends with empty bladder
anteversion bends anteriorly
retroversion bends posteriorly
uterine blood vessels enter at this point

20

body of uterus

aka corpus
between fundus and cervix
largest portion of the uterus
cavity funnel shaped coronal plane, slit-like sagittal plane
potential space for fluid accumulation-dynamic changes during menstrual cycle and pregancy
posterior to vesicouterine pouch and superior surface of bladder
anterior to rectouterine pouch ( pouch of douglas), ilium and colon

walls are together unless something is in there to separate them

21

fundus of uterus

widest portion of uterus

uppermost cephalic poriton of uterus

dome shaped

cornua - lateral borders of fundus, Fallopian tubes enter uterine cavity, interstitial portion of Fallopian tubes

22

layers of the uterine wall

3 histologic layers

perimetrium - serosa - outermost peritoneal covering (external layer)

myometrium - middle layer -muscular- thickest layer- primarily smooth muscle that is longitudinal and circular. contains main branches of uterine vessels and nerves

endometrium - inner layer - glandular tissue lining - mucous membrane - 2 layers which undergo monthly hormonal changes

23

endometrium

continuous with cervical canal - endocervical canal

changes dynamically responding to the cyclic hormonal changes. Appearance varies depedning on the patients menstrual status and period of life

two layers- zona funtionalis and zona basalis

24

zona funtionalis

superficial layer of glands and stroma (supporting tissue)

sheds with menses

25

zone basalis

basal layer

layer of endometrial glands which regenerate new endometrium after menses

26

uterine ligaments

anchor uterus in proper position in midline of pelvis

broad ligaments
round ligaments
uterosacral ligaments
cardinal ligaments

27

broad ligaments

double fold of peritoneum drapes over uterus, ovaries Fallopian tubes

lateral aspect of uterus to sidewalls of pelvis - provides lateral support for the uterus

covers both anterior and posterior surfaces of uterus

contain uterine vessels and nerves

3 separate areas: mesometrium, mesosalpinx and mesovarium

28

mesometrium

portion of broad ligament over the uterus

29

mesosalpinx

portion of broad ligament - upper fold encloses Fallopian tubes

30

mesovarium

posterior portion of the borad ligament that encloses the ovaries

31

round ligaments

hold fundus and body in forward position (anterior support)

attach to anterior lateral portion of fundus, extend to inguinal canal

insert into labia majora

holds uterine fundus in normal anteflexed position

32

uterosacral ligaments

attach posterior-lateral aspect of uterus at level of internal cervical os

extend posteriorly and inferiorly to sacrum

support cervix

with round ligaments hold uterus in normal anteflexed position

33

cardinal ligaments

aka: transverse cervical ligaments, mackenrodt ligaments or parametrium

provide lateral support of cervix and lower uterine segment

continuation of broad ligaments which extend across pelvic floor laterally from isthmus/cervix to pelvic sidewalls

with uterosacral ligaments hold cervix in fixed position

important landmarks for surgery - contain uterine vessels

34

explain the support system in the pelvis

explain which muscles and ligaments and where on the bone they attach

35

positions of the uterus

variable
most common anteverted/anteflexed
full bladder will tip average uterus backward

anteversion

anteflexion

retroversion

retroflexion

retroverted/retroflexed

dextroversion
dextroflexion
levoversion
levoflexion
uterine prolapse

36

anteversion

cervical canal forms 90 degree or smaller angle with vaginal canal anteriorly

37

anteflexion

fundas and body curved forward on cervix
approx 170 degree angle between uterine /cervical canal

38

retroversion

cervical canal forms > 90 degrees angle with vaginal canal (entire uterus tips posteriorly)

39

retroflexion

fundus and or body curved backward on cervix

two angles (version/flexion) are independent of each other - uterus can be in any combination of version and flexion

40

dextroversion

entire uterus/cervix tilts to the right

41

dextroflexion

uterine body at isthmus bends to the right

42

levoversion

entire uterus/cervix tilts to the left

43

levoflexion

uterine body at isthmus bends to the left

44

uterine prolapse

abnormal dropping of the uterus- uterine and pelvic floor muscles weak and allow uterus to protrude into the vagina

45

pelvic spaces

cul-de-sacs or gutters- potential spaces where fluid can accumulate

46

vesicouterine space

anterior cul-de-sac between bladder and fundus of uterus

47

rectouterine space

aka: "pouch of douglas"

posterior cul-de-sac between uterus and rectum

most inferior and posterior region of the peritoneal cavity

48

space of retzuis (reezts e us)

between symphysis pubis and anterior bladder wall

usually contains subcutaneous fat

hematoma or abscess may displace urinary bladder posteriorly

49

Fallopian tubes

also called oviducts or salpinx

coiled muscular tubes

normal length 7-12 cm in length, 1-4 mm in diameter

picks up egg released by ovary transports egg to endometrial cavity through peristaltic contractions of the muscle walls

innermost region-mucosal layer runs directly into endometrium

not able to visualize on US if normal

may use Doppler to distinguish between blood vessels and dilated tube

4 segments: interstitial, isthmus, ampulla, and infundibulum

50

Fallopian tube : interstitial portion

intramural

narrowest segment

passes through uterine cornua

connects to endometrial cavity

approx 1 cm long

51

ovaries

solid "almond shaped" structures

lie in ovarian fossa (waldeyer's fossa)

normal position: posterior-lateral to cornua, medial to external iliac vessels, anterior to internal iliac vessels and ureters

vary in size during lifespan depending on hormonal status

Fallopian tube + Ovary = ADNEXA

52

ovary blood supply

ARTERIAL:
dual blood supply
arterial blood via gonadal arteries from aorta
ovarian arteries arise in distal aorta-distal to renal arteries
ovarian arteries anastamose with uterine artery in broad ligament
ovarian branch of uterine artery continues to feed ovary

VENOUS DRAINAGE:
right ovarian vein drains directly into IVC
Left ovarian vein drains into Left renal vein

53

ovarian size

average ovarian length in menarcheal female 3.0 cm

size dependent on menstrual/hormonal status (menarcheal 2.5-5.0cm in length, 1.5-3.0 cm in width and height)

volume (L x W x H x 0.523) know this formula)
pre-puberty: up to 8 cc
Mernarcheal: up to 18cc (usually 6-10 cc) (3.0x2.0x2.0cm x 0.523)
Post- menopausal: up to 8cc (usually 5.8 cc) (2.0x0.5x1.0cm x 0.523)

54

what are the different positions of the ovaries?

for scanning purposes not for test...

ovaries are mobile and may change in position based on pregnancy, ligament laxity, previous surgeries/pathology, uterine position and bladder filling

May Lie:
anterior to the internal iliac vessels
medial to the external iliac vessels
from the posterior cul-de-sac to the lower abdomen
orientation may be vertical, horizontal or anywhere in between

55

normal anatomy for ovary

cortex -

medulla -

ovum -

hormones -

56

estrogen and progesterone

hormones produced by ovaries

responsible for producing and maintaining secondary gender characteristics, preparing uterus for implantation and development of mammary glands

estrogen: secreted by follicles

Progesterone: secreted by corpus luteum

57

ovarian ligaments

ovarian ligament

suspensory ligament -

mesovarian ligament -

58

Pelvic Vasculature

Ao to common iliac arteries (ant and med to psoas muscles)

Common iliac arteries - external and internal iliac (hypogastric) arteries

uterine Artery -

arcuate arteries -

radial arteries (branches of arcuate arteries)

straight and spiral arteries

59

explain the blood supply to the pelvis and it's structures

finish
venus flow is the same as arterial just backwards

60

what makes up the bony pelvis?

two compartments divided by iliopectineal line - superior border of sacrum to superior margin of pubis symphysis

false pelvis

true pelvis

pelvic brim - corresponds with iliopectineal line and sacral promontory

61

what bones make up the bony pelvis?

from the right of the spine:
posterior superior iliac spine
iliac crest
tubercle of crest
anterior superior iliac spine
acetabulum
ischial tuberosity
ischiopubic ramus
pubic symphysis
obturator foramen
lesser sciatic notch
ischial spine
greater sciatic notch
posterior sacral foramen
sacrum
coccyx

62

where is the perineum?

It the area below pelvic floor

63

where is the piriformis muscles?

posterolateral wall
triangular, flat muscles
anterior sacrum through greater sciatic notch
inserts to superior aspect of greater trochanter of femur
posterior to rectum, vagina and uterus

64

where are the obturator internus muscles?

anterolateral wall
trianglular sheets of muscles
anterolateral pelvic wall
surround obturator foramen
through lesser sciatic notch
inserts to superior aspect of greater trochanter
lateral at the level of the transverse cerix

65

what is the pelvic diaphragm?

floor of the true pelvis
formed by levator ani and coccygeus muscles

66

levator ani muscles

3 muscle groups
role in rectal and urinary continence
forms anterior part of diaphragm
forms "hammock" to support rectum and pelvic floor
*major supporting structure for pelvic structures*

67

puboccygeus muscles

most anterior and medial
pubic bones to coccyx
surround urethra, vagina and rectum

68

iliococcygeus muscles

anterolateral pelvic wall to coccyx

69

puborectalis muscles

lower part of pubic symphysis
surround lower part of rectum
form sling

70

what are ureters?

ureters- tubes from kidneys to trigone of bladder. anterior to the internal iliac arteries. posterior to ovaries and uterine arteries. 'jets" in the posteriorinferior portion of the bladder with color doppler.

71

what are the layers of the uterus?

perimetrium

myometrium

endometrium

72

what is premenarchal uterine size?

length: 1.0-3.0 cm
width: 0.5-1.0cm
AP cm: 0.5-1.0
volume: n/a
Cervix/corpus ratio: 1/2 : 1/2

73

what is the uterine size for menarchal nulliparous?

length: 6.0-8.0 cm
width: 3.0-5.0 cm
AP cm: 3.0-5.0
volume cc: 30-40
cervix/corpus ratio: 1/3 : 2/3

74

what is the uterine size for menarchal parous?

Length: 8.0-10.0cm
width: 5.0-6.0cm
AP cm: 5.0-6.0
volume cc: 60-80
cervix/corpus ratio 1/3 :>2/3

75

what is the uterine size of postmenopausal?

length: 3.0-5.0cm
width: 2.0-3.0cm
AP cm: 2.0-3.0
volume cc:14-17
cervix/corpus ratio: 2/3 :1/3

76

what is the exocervix?

squamous epithelium
continuous with the vagina

77

what is the endocervix?

cervical canal
columnar cells, excrete mucus
constricted at upper end by internal os - communicates to uterine cavity
constricted at lower end by external os - communicates to vagina

78

retroverted/retroflexed uterus

uterus tipped and flexed backward...a common varient

79

Fallopian tube : isthmus

medial portion between interstitial portion and ampulla

increases in diameter as it extends towards ampulla

thick muscular wall

approx. 2cm long

80

Fallopian Tube: ampulla

longest
most coiled portion

area where fertilization of the ovum usually occurs

most distensible region of tube

approx 5 cm long

81

Fallopian Tube: infunibulum

Wide, trumpet shaped, lateral portion

fimbriae - fringe like structures - extend toward ovary (direct ovum into the Fallopian tube

82

ovarian anatomy: Cortex

outer layer

consists primarily of follicles in various stages

covered by dense connective tissue TUNICA ALBUGINEA

TUNICA ALBUGINEA COVERED BY THIN LAYER OF CELLS- GERMINAL EPITHELIUM

83

Ovarian anatomy: Medulla

central portion

composed of connective tissue - blood nerves lymphatics

smooth muscle at hilum

84

what do ovaries produce?

an OVUM (a reproductive cell)

hormones

85

Ovarian Ligament

medial support

originate bilaterally at the cornua of the uterus

attach to lower pole of ovary

keeps ovary close to uterus

86

suspensory ligament of the ovary

aka: infundibulopelvic

from infundibulum to Fallopian tube/ovary to sidewall of pelvis

keeps ovary close to Fallopian tube

87

Mesovarioum (ovarian support)

attaches ovary to posterior aspect of broad ligament

88

What is the pelvic vasculature?

Ao -> common iliac arteries -> uterine artery -> arcuate arteries -> radial arteries -> straight and spiral arteries

VENOUS SYSTEM:
left ovarian vein drains into left renal vein
right ovarian vein drains directly into IVC

89

common iliac arteries

external and internal iliac (hypogastric) arteries

external iliac arteries continue to legs- femoral artery

internal iliac arteries feed bladder, uterus, vagina and rectum

90

uterine artery

anterior branch of internal iliac artery - through the base of broad ligament to cervix

tortuous

spirals up sides of uterus to cornua

travels laterally to anastomose with ovarian artery

91

arcuate arteries

many branches perforate serosa, carry blood to myometrium...these form the arcuate arteries

circle uterus

visualized in outer 3rd of uterus as anechoic tubular structures

92

radial arteries

branches of arcuate arteries

penetrate myometrium at 90 degree angle to base of endometrium

93

spiral arteries

supply zona basalis of endometrium

lengthen during regeneration of endometrium after menses to supply zona functionalis

supply blood to inner 2/3 of endometrium

supply proliferating endometrium each menstrual cycle

blood from spiral arteries is shed during menses

responds to hormonal changes of ovary

94

straight arteries

supply zona basalis of endometrium

supply blood for outer 1/3 of endometrium

NOT affected by menstrual cycle

maintains blood supply

allows regrowth of endometrium