Workbook 1 Flashcards
Differences between male and female pelvis
Males have narrower, heart shaped, taller and with acute pubic arch.
Females have wider, rounder, shorter and with wider pubic arch
Pelvic measurements:
Diagonal conjugate, true conjugate, interspinous distance and intertuberous distance
Diagonal conjugate is taken from the inferior margin of pubic symphesis to the sacral prominance. Depth of pubic symphesis allows calculation of true conjugate (Bladder is the way of measuring).
Interspinous is distance between ischial spines, intertuberous distance is between the pubic tuberosities.
Levator ani and surrounding
Obturator externis laterally, with levator ani in middle (Separated by tendinous arch). Has pubococcygeus, ischiococcygeus and puborectalis. Coccygeus is not levator ani but there too
Blood supply is inferior gluteal, and Innervated by the anterior ramus of S4 and branches of the pudendal nerve (roots S2, S3 and S4).
What are the main routes of venous drainage from the pelvic organs?
Largely into the internal iliac veins, which then drain into the common iliac veins and
subsequently into the IVC. There is a plexus around the rectal veins and this plexus can
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drain into the superior rectal vein which empties into the inferior mesenteric vein before
entering the portal heptaic system.
While most of the veins follow the arteries, the deep dorsal vein (from the clitoris and the
penis) does not follow the internal pudendal artery but instead passes through a gap
between the arcuate pubic ligament and the anterior of the perineal membrane where it
enters the pelvic cavity and joins a plexus (prostatic plexus in men and vesical plexus in
women)
What do the myometrium and the stomach have in common
3 layers
Describe the nerve supply of the uterus. Which sensory nerves are involved and what is
their origin?
Sympathetic innervation is via the inferior hypogastric plexus, while parasympathetic
innervation is via the pelvic splanchnic nerves (S2-S4).
The sensory (afferent) fibres are T10-T12 and L1.
Normal uterus conformation
Anteflexed and antiverted. Flexed is the angle through the uterus, verted is the angle between uterus and vagina
Information from looking at cervix
round in nulliparous, slitlike in multiparous. Pointing down if antiverted, pointing up if retroverted.
The transormation zone starts up in the endocervix and moves down to the ectocervix
during puberty/pregnancy
Where might cervical cancer spread to?
External and internal iliac lymph nodes. Can spread to rectum and bladder. Can metastasize to
lung, liver, bone and bowel (about 5% of patients).
Water over bridge in females?
1cm lateral to lateral fornix, ureter runs and uterine artery passes over it.
Relations of the ovary
Ovaries sit posteriosuperiorly to the uterus. Have fallopain tubes above them. Parietal peritoneum lines the walls, and behind this sits the ureters, internal iliac vessels, obturator vessels, obturator nerve, uterine artery
Closeness to obturator can lead to thigh pain in ovarian pathology
Locations of deep and superficial inguinal rings
Deep is 1.5cm above midpoint between ASIS and PS (or midpoint between pubic tubercle and ASIS), superficial is lateral to pubic tubercle.
Deep is invagination of transversalis fascis, superficial is invagination of external oblique aponeurosis
Male inguinal canal
Has spermatic cord, genitofemoral nerve and inguinal nerve.
Testes descend through them before birth.
Men more at risk of direct and indirect hernias than women (due to men having longer canal)
Male inguinal canal is larger than womens
Female inguinal canal
Has round ligament, genitofemoral nerve and ilioinguinal nerve.
Ovaries don’t descend as prevented by broad ligament.Women are more likely to suffer indirect than direct hernia.
Women are more likely than men to suffer femoral hernia (as pelvis is wider). Inguinal canal is amall in women.
What does the gubernaculum become in men/women
ovarian ligament and round ligament in women, scrotal ligament in men
Breast bed, and nerve near axillary tail
Breast bed goes from 2nd or 3rd rib to 6th or 7th rib, and from lateral sternum up to mid-axilla. Axillary tail (tail of spence) goes into axilla. Long thoracic nerve runs near axilla.
Breast anatomy
Underlying muscles are pectoralis major and serratus anterior. Fascia lies over this. Then the retromammary space with breast tissue (therefore, breast should not move on pec contraction). Suspensoty ligaments support breast. Lactiferous duct connects gland to nipple.
Lymph drainage is medially, laterally, into axilla and also superior (supraclavicular) - main lymph nodes are CHAAPS (central, humoral, anterior, apical, posterior and supraclavicular)
HPV
DNA virus. Strains 16 and 18 associated with cervical cancer, strains 6 and 11 for warts.
Where does nutrient exchange take place at the placenta
In the space between chorionic villi and intervillous space
Placental hormones
Human chorionic hormone (promotes pregnancy)
Human placental lactogen (antiinsulin hormone to imcrease maternal blood glucose)
Human chorionic thyrophin
These are protein hormones, also produces steroid hormones (progesterone and oestrogen)
Physiological changes in pregnancy
Blood glucose increase (so measure Hsb1C), Blood pressure drops, GFR increases, thyroid gland increases (iodine excreted more), T3 and T4 levels rise as oestrogen stimulates thyroxine binding globulin (but not hyperthyroid as TSH and free hormones are same); fungal and bacterial infections can establish easier (Igs decrease)
Total Hb rises, but plasma increases so haematocrit falls.
WBC and platelets increase
CO increases
Tidal volume increases (after decrease in vascular resistance and RAAS)
Increased pelvic capacity increases urinary stasis so UTI increase risk
Quadrupole screen test
Alpha fetoprotein (produced by the fetus), human chorionic gonadotrophin (produced by the
placenta), estriol (produced by fetus and placenta) and inhibin A (produced by placenta and
ovaries). AFP can show spina bifida, omphacele, Turner syndrome, Edward syndrome. hCG
shows placental problems, estriol shows placental and fetal health and inhibin A shows
placental and ovarian health.
How can chromosomal abnormalities be investigated?
Amniocentesis (needle through abdo into amniotic fluid - has 1% risk of miscarriage)
Chorionic villous sampling (placenta sample, either transvaginal or abdo - has 1% risk of miscarriage)
How can labour be stopped?
Tocylytics, e.g.oxytocin antagonists (e.g.atosiban) or beta 2 agonists (salbutamol,terbutaline), calcium channel blocked (nifedipine)
Nifedipine and terbutaline are most common
Difference between mitosis and meiosis
Mitosis has the following stages: Interphase, followed by prophase, metaphase, anaphase and
telophase. In meiosis, this process is repeated twice, but during prophase 1, homologous
recombination occurs which increases genetic diversity.
Mitosis produces two diploid daughter cells, while meiosis produces two halpoid daughter cells.
oocyte development
The oogonium is the primordial germ
cell. Before birth, it replicates by mitosis to produce 2n daughter cells. At birth, these oogonia
arrest at prophase 1 of meiosis (forming primary oocytes). After puberty, the oocytes complete
meiosis 1 (expelling a polar body) and then arresting at metaphase 2. Metaphase 2 completes
on fertilisation and another polar body is expelled.
Anatomical lobes of the prostate, and functional zones
anterior lobe sits anterior to urethra. MEdian lobe is posterior to urethra and superior to posterior lobe. Posterior lobe is posterior to urethra and inferior to median lobe.
For zones, there is the transition zone that sits innermost around the urethra. It can
only expand into the urethra. Zone 2 is the central zone and it is glandular tissue that
sits near the bladder posteriorly. Zone 3 is fibrous stromal tissue that sits inferior to the
bladder on the anterior prostate aspect. Zone 4 is the peripheral zone, and is where
most of the secreting glands are located. Zone 4 is known as the danger zone as it is
where most prostate cancers develop.
Is there a female homologue to prostate gland?
paraurethral glands (skene’s glands)
Seminal vesicles (relations)
Posteriosuperior to prostate, but excrete into prostate. Secretions make up the bulk of semen, is fructose based and alkaline, plus PGs
Prostatitis symptoms
Dysuria, pain on ejaculation, premature ejaculation. Fatigue, malaise. Pain in testes, groin, suprapubic area or back. ED
Post prostate surgery/radiation ED
Cevernous nerve injury, leads to less NO and reduced oxygenation of eretile tissue. Prolonged hypoxia leads to fibrosis. Effects can last 12-24 months.
penis structure
The penis has 3 roots, right and left crura and a bulb. The crura go on to make the copora cavernosum- both have deep arteries and sit superiorly. Attaches to pubic arch.. The bulb makes up the corpus spongiosum sits inferiorly and contains the urethra (an extension of the spongiosum is the glans). Spongiosum attaches to perineal body. They are surrounded by tunica albuginea (inc. each corpora cavernosum). Deep dorsal vein, dorsal arteries, and dorsal nerves in next layer. Then deep (Buck’s fascia). Then superficial vein. Then dartos (superficial) fascia. Then skin
Penis has 2 ligaments supporting it from pubic symphesis: suspensory and fundiform
Innervation to the penis
The parasympathetic innervation is via the pelvic splanchnic nerves (S2-4) that run in the
spinal nerves of S2-4 and join with hypogastric nerves to form inferior hypogastric plexus.
The cavernous nerves descend from the prostatic plexus (male) and uterovaginal (female)
plexuses and penetrate into the deep perineal pouch, pass through the perineal membrane
and innervate the erectile tissue.
Sympathetic supply is from T11-L2, travel down in the superior hypogastric plexus (which
divides into right and left hypogastric nerves). The hypogastric nerves are joined by sacral
splanchnic nerves which make up the inferior hypogastric plexus. From here, there is the
prostatic plexus (male) and utervaginal plexus (female). From these, the cavernous nerves
arrive and these penetrate the perineal membrane. These cause tonic contraction of smooth
muscle of the helicine arteries and venous sinusoids to inhibit erection.
The inferior hypogastric plexus therefore has both sympathetic and parasympathetic
innervation.
Function of bulbospongiosus and ischiospongosus (male and female)
Muscles found in superficial perineal space.
In males the muscle helps compress the crus of the penis to maintain and stabilize the erect penis. In females, it similarly helps maintain clitoral erection in conjunction with the bulbospongiosus muscle.
In women 2 x bulbospongiosus and 2 x ischiocavernosus. In men, 1 bulbospongiosus and 2 x ischiocavernosus.
Innervation to internal urethral sphincter
Sympathetic fibers from T10-L2 through the inferior hypogastric plexus then vesical nervous plexus
Testicle anatomy
Has tunica albuginea, then tunica vaginalis (only on anterior), then internal spermatic fascia, then cremaster, then external spermatic fascia, then dartos, then skin.
Seminiferous tubules are anterior, then rete testes, then efferent ductules, then head, body and tail of epididymis, leading to vas deferens
Pampinifirm plexus is network of veins that cool blood in testicular artery
dartos is scarpas, external spermatic is external oblique, cremaster is internal oblique, internal is transverse fascia
Inside spermatic cord
Cremasteric artery (from inferior epigastric), artery to ductus deferens (from inferior vesicle artery), testicular artery (from abdo aorta). Lymphatics, pampiniform plexus, ductus deferens ilioinguinal nerve, genitofemoral nerve (cremaster), sympathetics external fascia, creamster and internal fascia.
Ilioinguinal is cremasteric reflex afferent (L1), genitofemoral pulls ipsilateral testicle up (cremaster muscle, L1/L2).
Female vulva innervation, compare to scrotum
Female
Anterior – ilioinguinal nerve, genital branch of the genitofemoral nerve
Posterior – pudendal nerve, posterior cutaneous nerve of the thigh. Scrotum is Anterior and anterolateral aspect – Anterior scrotal nerves derived from the genital branch of genitofemoral nerve and ilioinguinal nerve (L1) Posterior aspect – Posterior scrotal nerves derived from the perineal branches of the pudendal nerve and posterior femoral cutaneous nerve. (S3)
Where is the location of testes/ovarian lymph drainage/vascular supply/drainage
L1, para-aortic
Why does testicular cancer not normally cause a swelling of the inguinal lymph nodes
as you might expect? What would you deduce if a man with testicular tumour had
enlarged inguinal lymph nodes? (explain your answer).
The testes drain into the para-aortic lymph nodes (around L1) and so swellings of the
inguinal lymph nodes are not due to direct testicular cancer spread through lymphatics.
However, the inguinal lymph nodes do drain the scrotum, and so swelling here in the
presence of testicular tumour means the tumour may have infiltrated the scrotum.
Boundaries of inguinal canal
Floor: Inguinal ligament (part of the aponeurosis of the external
oblique, thickened medially by the lacunar ligament
Roof: Transversalis fascia, internal oblique and transversis abdominis
Anterior:Aponeurosis of the external oblique, reinforced by the internal
oblique
Posterior:Transversalis fascia
Define hydrocoele, spermatocoele, varicocoele
Hydrocoele is fluid in tunica vaginalis, spermatocoele is benign sperm filled cyst in head of epididymus. Varicocoele is dilated veins in the pampiniform plexus. It is more common on the left due to the
right angle drainage of the left testicular vein to the left renal vein. The pampiniform plexus combines to form the right and left testicular veins which drain into
the the left renal vein (on the left) which crosses over the aorta into the IVC, while on the
right the right testicular vein drains directly in the IVC.
why might prostate cancer cause severe back pain or
sciatica?
The prostatic plexus drains into the internal iliac vein, which also receives blood from
the internal vertebral vein. These veins are valveless, and there is the potential for
blood to facilitate metastasis of prostate cancer into the vertebral bodies and also nerve compression (sciatica).
Level of kidneys, and level of kidney hilum.
Which structures might be inadvertently punctured during a renal biopsy?
Left is T11-L1/2, right is T12-L2/3. Hilum is at L1
The iliohypogastric and ilioinguinal and genitofemoral nerves could be damaged, as could the arteries and
veins for the surrounding organs. Also, the parietal pleura lies at T12, and this means they
can be punctured, leading to pneumothorax or diaphragmatic injury. Also, Sits anterior to psoas major so damage around kidney could impact on hip flexion.
Urothelium
Transitional epithelium found in the bladder, allows adjustments for changing capacity
Renal blood supply
Renal artery - > segmental artery - > lobar artery-> interlobar-> arcuate artery - > interlobular artery - > afferent arteriole-> capilliaries - > efferent arteriole - > interlobar vein - > lobar vein - > renal vein - > IVC
There are no anastamoses between lobes, so kidney can be resectioned easily, but runs risk of ischaemia as no collateral supply.
Spleen is also like this with end arteries
3 glomerular filtration layers
The epithelial layer has pores that limit the size of material moving through. The basement
membrane has negatively charged proteins embedded in it to repel negatively charged
species and proteins. And the podocytes have slits (created by gaps between mesangial
cells)
Ureter pathway
Which structures serve as a reliable radiological landmark for the ureters?
The ureters move along the sides of the vertebral column (retroperitoneal structure). It
then passes anterior to psoas major and crosses over the genitofemoral nerve. It is
crossed by the gonadal vessels. It then runs slightly laterally, then medially. In women,
it is crossed by the uterine artery, in men it is crossed by the ductus deferens. It enters
the pelvis anterior to the bifurcation of the common iliac artery The opening of the
ureter into the bladder is an oval shape which helps to prevent reflux of the urine back
into the ureters.
In summery:
1) Posterior to parietal pertoneum
2) Anterior to psoas major
3) Anteriot to genitofemoral nerve
4) Posterior to gonadal vessels
5) Anterior to bifurcation of common iliac
6) Posterior (under) uterine artery/ductus deferens
Tips of L2-L5 transverse processes mark the course of the abdominal ureters, and the
ischial spines are a landmark for the vesico-uteric junctions.
patent
urachus,
Remnant of fetal alantois
Neurovascular supply to bladder
Urethral: Males have an internal urinary sphincter that relaxes under parasympathetic control (s2-S4
sacral segments) and constricts under sympathetic control T10-L2.
Men and women both have an external urinary sphincter that is under somatic control via pudendal
Bldder innervation
Sympathetic – hypogastric nerve (T12 – L2). It causes relaxation of the detrusor muscle, promoting urine retention. Parasympathetic – pelvic nerve (S2-S4). Increased signals from this nerve causes contraction of the detrusor muscle, stimulating micturition. Somatic – pudendal nerve (S2-4). It innervates the external urethral sphincter, providing voluntary control over micturition.
Blood supply is: Superior aspect is via the superior vesicle arteries (from the internal
iliac).
In females, the vaginal arteries (from the internal iliac artery) supplies
the inferior part (inferior vesicle arteries from internal iliac).
Lymphatic drainage is To the external and internal iliac lymph nodes
Greater
vestibular gland
Bartholin’s glands) that assist in vaginal lubrication - analogous to bulbourethral gland in the maleskene
Suprapubic catheterisation
Go through skin, campers, scarpas, linea alba, transversalis fascia, pre-peritoneal fat, peritoneum, bladder. If bladder full then peritoneum will be lifted out of the way (therefore organs safe)
