Anatomy Flashcards
Blood Supply to the Uterus (and origin of vessel(s))
Uterine artery (origin:internal iliac artery-common iliac artery-abdominal aorta) Collateral supply from ovarian arteries (origin:abdominal aorta)
Venous Drainage of the Uterus
Uterine veins (from internal iliac vein-common iliac vein-inferior vena cava)
Which bones form the bony pelvis?
2 hip bones, sacrum and coccyx
Bones of the Pelvic Inlet
Sacral promontory, ilium, superior pubic ramus, pubic symphysis
Bones of the Pelvic Outlet
Pubic symphysis, ischiopubic ramus, ischial tuberosities, sacrotuberous ligaments, coccyx
Where is the False Pelvis?
Above Pelvic inlet
Where is the True Pelvis?
Below Pelvic inlet
Where is the Pelvic Cavity?
The space betweem the pelvic inlet and the levator ani muscle
5 Functions of the Bony Pelvis
1) Support of he upper body when sitting and standing
2) Transference of weight from vertebral column to femurs allowing standing and walking
3) Attachment for muscles of locomotion and abdominal wall
4) Protection of pelvic organs, their blood and nerve supply, their venous and lymphatic drainage
5) Passage for childbirth
Bones that make up the hip bone
ilium, ischium, pubic bone
Bony features of the Ilium
Iliac crest Anterior superior iliac spine Posterior superior iliac spine Iliac fossa Anterior inferior iliac spine Posterior inferior iliac spine
Bony features of the ischium
Ischiopubic ramus
Ischial tuberosity
Ischial spine
Pubic Bone
Superior pubic ramus Pubic tubercle Ischiopubic ramus Pubic arch Subpubic angle
Joints of the Bony Pelvis
Sacroiliac joints Hip joints (femur and acetabulum) Pubic symphysis
Palpable Surface Landmarks of the Bony Pelvis
Iliac crest ASIS Pubic Symphisis Pubic Tubercle PSIS Ischial Tuberosity Sacrum Coccyx
Ligaments of the Bony Pelvis
Sacrospinous ligament: Sacrum to ischial spine
Sacrotuberous ligament: Sacrum to ischial tuberosity
Foraminae of the Bony Pelvis
Obturator foraminae (obturator artery, vein and nerve) Greater and lesser sciatic foraminae
Blood vessels in the pelvis at risk of haemorrhage
common iliac artery and common iliac vein
Sutures and fontanelles of the foetal skull
Midline sagittal suture
Coronal suture
Lambdoid suture
Anterior and posterior fontanelles
Moulding
Movement of one bone over another to allow the foetal head to pass through the pelvis during labour
Vertex of the foetal skull
An area of the foetal skull outlined by the anterior and posterior fontanelles and parietal eminences
Which diameter of the foetal skull is longer?
The occipitofrontal diameter is longer than the biparietal diameter
Position of foetal head at the pelvic inlet during labour.
Transverse
Position of foetal head whilst descending through the pelvic cavity.
Rotated and in a flexed position
Position of the foetal head at the pelvic outlet?
Occipitoanterior position and in extension
Differences between male and female pelvis
The AP and transverse diameters of the female pelvis are larger than the male at both the pelvic inlet and outlet
The subpubic angle (and pubic arch) in the female is wider than the male
The pelvic cavity is shallower in the female
Which parts of the female reproductive system are in the pelvic cavity?
Ovaries, uterine tubes, uterus and most of the vagina
Which parts of the female reproductive system are in the perineum
Inferior part of the vagina, perineal muscles, bartholins glands, clitoris, labia
What does the parietal peritoneum form
It forms the floor of the peritoneal cavity and a roof over the pelvic organs.
Where is the pouch of douglas?
The rectouterine pouch, the most inferior part of the peritoneal cavity
Where is the broad ligament?
Suspends the uterus, uterine tube and ovary from the lateral wall of the pelvic cavity
Where is the round ligament?
Attaches the uterus to the perineum
What are the 3 layers of the wall of the body of the uterus?
Perimetrium,myometrium, endometrium
Which layer of the uterus is shed during menstruation?
The endometrium
Where should implantation of the fertilised ovum occur?
The body of the uterus
Which layers hold the uterus in place?
1) Strong ligaments (e.g.uterosacral ligaments)
2) (endo)pelvic fascia
3) Muscles of the pelvic floor e.g. levator ani
What is the most common position of the uterus?
Anteverted and anteflexed
Uterus tipped anteriorly relative to the axis of the vagina and the uterus is tipped anteriorly relative to the axis of the cervix.
Where is sampled in a cervical smear?
The squamo columnar junction
Where is the widest part of the uterine tube?
The ampulla
What is a salpingectomy?
Removal of a uterine tube
How is there a communication between the genital tract and the peritoneal cavity?
The fimbriae at the end of the uterine tubes open into the peritoneal cavity
What do the ovaries secrete? In response to what?
They secrete oestrogen and progesterone in response to anterior pituiary hormones (FSH and LH)
How do the ovaries move during foetal development?
They move from the posterior abdominal wall into the pelvis. A structural remnant of this embryology is the round ligament of the uterus
What are the parts of the vaginal fornix?
Anterior, posterior and 2 lateral
Where is the perineum located?
Inferior to the levator ani muscle
What is the nerve supply to levator ani?
“Nerve to levator ani”: a branch of the sacral plexus
What is the role of the levator ani?
Provides support for pelvic organs by being tonically contracted most of the time
It reflexively contracts further during sitations of increased intra-abdominal pressure
What is the perineal body?
A bundle of collagenous and elastic tissue into which the perineal muscles attach
What nerve supplies the perineal muscles?
pudendal nerve
What are the Bartholins glands?
2 pea-sized glands located slightly posterior and to the left and right of the vagina. They secrete mucus for vaginal lubrication
What is the vestibule?
The area within the labia minora containing the external urethral origace and the vaginal orifice
What are the borders of the female breast?
Ribs 2 and 6
What lies beneath the female breast?
Retromammary space ad pectoralis major
What do the suspensory ligaments of the breast do?
Attach breast tissue to overlying dermis of skin
Blood supply of the female breast
Lateral thoracic artery (from axillary- from subclavian artery)
Internal thoracic artery (from axillary- from subclavian artery)
Venous drainage of female breast
Internal thoracic vein (to brachiocephalic vein)
What is the axilla?
The pyramidal space between the arm and chest
Superior border of the axilla
Outer border of first rib, superior border of scapula, posterior border of scapula
Anterior border of axilla
Pectoralis major, pectoralis minor and subclavius
Posterior Border of axilla
Subscapularis, teres major and latissimus dorsi
Medial Border of axilla
Serratus anterior and ribcage
Lateral border of axilla
Intertubercular sulcus
Contents of the axilla
Branches of brachial plexus
Axillary artery and its branches
Axillary vein and tributaries
Axillary lymph nodes
Which lymph nodes can lymph from the breast drain into?
75% drains into the ipsilateral axillary lymph nodes
Can also drain to the supraclavicular and parasternal lymphnodes
Lymph from the lower inner breast can drain to the abdominal lymph nodes.
Describe the levels of axillary lymph nodes.
Level 1: Inferior and lateral to pectoralis minor
Level 2: Deep to pectoralis minor
Level 3: Superior and medial to pectoralis minor
Blood supply of ovary
Ovarian artery (abdominal artery) Uterine artery (internal iliac artery, common iliac artery, aorta)
Venous drainage of ovary
Ovarian vein (inferior vena cava [left renal vein])
Blood supply of vagina
Uterine artery (internal iliac artery) Vaginal artery (internal iliac artery or uterine artery)
Venous drainage of the vagina
Vaginal venous plexus (internal iliac veins)
What are the common surgical incisions in Obs and Gynae? (2)
Vertical midline incision: laparotomy
Suprapubic/Pfannenstiel/bikini-line incision: LSCS, abdominal hysterectomy,
What is the Rectus Sheath?
The combined aponeuroses of the external oblique, internal oblique and transversus abdominis muscles that surround the rectus abdominis muscles
What is the Linea Alba?
Formed by the interweaving of the muscle aponeuroses that form the anterior and posterior rectus sheath. It runs from the xiphoid process to the pubic symphysis
What is the fibre direction of the external oblique?
Anteromedial and inferiorly
What is the fibre direction of the internal oblique
Posterolateral and inferiorly
What is the fibre direction of the transversus abdominis?
Horizontal
What is the nerve supply to the anterolateral abdominal wall?
7th-11th intercostal nerves Subcostal nerve (T12 anterior ramus) Iliohypogastric nerve (half of L1 anterior ramus) Ilioinguinal nerve (other half of L1 anterior ramus)
What is the blood supply to the anterolateral abdominal wall?
Superior epigastric artery (continuation of internal thoracic artery [from axillary artery])
Intercostal and subcostal arteries
Inferior Epigastric Artery (branch of external iliac artery)
What layers need to be opened in an LSCS?
Skin, fascia, anterior rectus sheath, rectus abdominis, fascia and peritoneum, uterine wall, amniotic sac
What layers need to be opened for a laparotomy?
Skin, fascia, linea alba, peritoneum
What is the path of the inferior epigastric artery?
Emerges as a branch of the external iliac artery, just medial to the deep inguinal ring. It then passes superomedial direction posterior to the rectus abdominis.
How do you differentiate between the uterine artery and the ureter?
The ureter passes inferior to the uterine artery and vermiculates when touched.
