Obs gyn anatomy

Question 1

Bones

Answer 1

Innominate bones - paired –> ischium, ilium, pubis (join together at pubic symphysis)
Sacrum (articulates with L5 and coccyx)
Coccyx

True pelvic inlet is promontory –> superior pubic bones surface
True pelvic outlet is tip of coccyx –> inferior surface of pubic symphysis

Ischial spines important for assessing station in labour

Question 2

External genitalia

Answer 2

Mons pubis
Labia majora - hair and sweat glands - cutaneous folds
Labia minora - erectile, innervated and vascularised - cutaneous folds
Clitoris - two corpora cavernous enclosed in fibrous sheath
Vestibule - shallow depression between labia minor
Skene’s ducts - lower 1cm of urethra
Vaginal orifice
Bartholin’s glands - racemose glands either side of vaginal introitus –> makes girls wet

Question 3

Internal organs

Answer 3

Vagina - 6.5-7cm long, squamous epithelium
- Copulation, parturition and drainage of menstrual loss

Uterus - hollow, pear shaped - 7.5cm long and 5cm across

• Corpus –> outer transverse, middle circular, inner all 3
• Cervix - barrel shaped - columnar mucous secreting epithelium
• Isthmus - 2-3mm in non-pregnant –> forms lower segment

Question 4

Supports and ligaments of the uterus

Answer 4

Anterior ligament - from the cervix to the superior surface of bladder - weak supporting role
Uterosacral ligaments - MAJOR - cervix –> anterior sacrum
Broad - reflected folds of peritoneum –> lateral pelvic walls, weak support
Round - two fibrumuscular from anterior surface of uterus –> lateral pelvic walls –> strengthened during pregnancy
Cardinal - STRONGEST - fascial thickenings from cervix –> fasciae over obturator fossa

Muscles of pelvic floor and perineal body also important in prolapse

Question 5

Fallopian tubes

Answer 5

Enclosed in mesosalpinx
Interstitial, isthmus, ampulla, infundibulum
Ciliated columnar
Innervated richly and rhythmicity

Question 6

Ovaries

Answer 6

Paired, almond shaped 2.5-5cm / 1.5-3.0cm

Close proximity to external iliac and ureter

Anterior border to posterior layer of broad ligament

Cuboid or low columnar germinal epithelium

Blood supply and nerve enter in medulla

OPENS DIRECTLY INTO PERITONEAL CAVITY

Question 7

Blood supply

Answer 7

Internal iliac artery –> anterior and posterior

Anterior –> Makes superior, middle and inferior vesical arteries AND THE uterine artery (which gives off vaginal branch)
uterine, superior, middle, vaginal –> anastomose with contralateral vessels
Uterine also anastomoses with Ovarian (which is a branch of the abdominal artery itself)

Posterior –> ilio lumbar and lateral sacral and superior gluteal branches

External iliac –> Common femoral

Question 8

Lymphatics

Answer 8

Vagina, vulva, perineum and anus –> superificial inguinal and adjacent superficial femoral

Pelvic parietal –> iliac nodes –> aortic

Cervix, uterus, and upper portion of vagina –> iliac –> aortic

Fundus, fallopian tubes and ovaries –> straight into aortic
SOME OF FUNDUS –> deep and superficial inguinal nodes

Question 9

Nerves

Answer 9

Somatic - Pudendal S2-S4

• Sensory - clirotris through dorsalclitoris nerve
• Perineal pain mediated through these nerves

Autonomic
Sympathetic
- T10/T11 - ovaries and tubes
- T11-L2 - uterus and cervix

Parasympathetic - S1-S3

Question 10

Pelvic floor and perineum

Answer 10

Levator ani - pubo/ileococcygeus, puborectalis
Perineum - all structures that lie below pelvic floor - anterior and posterior triangles with bases of both the deep transverse perineal muscles

Ischioretal fossa - between anal canal and lateral wall of fossa formed by inferior ramps of ischium
- Pudendal nerve and internal pudendal vessels –> through lateral aspectst of fossa –> in Alcock’s canal

TRANSverse PERNIEAL superficial and DEEP
Ischiocavernosus - anterior borders
Levator ani - posterior borders