Sem 2 - A - Pelvic contents - Peritoneum, Bladder/rectum/uterus/ovaries arteries/veins/lymph, associated ligaments Flashcards
What is the most anterior pelvic organ?
This would be the bladder - sits directly behind the pubic bone
Due to the presence of different pelvic organs, the peritoneal cavity differs in structure between the sexes.
When humans stand or sit upright, any superfluous fluid (which could be blood, pus, or infected fluid) is likely to collect in the most inferior portion of the peritoneal cavity. Thus, it is clinically important to be aware of the differences between males and females.
- Describe the two pouches in females?
Vesicouterine pouch - double fold of peritoneum between the bladder & then backwards onto the uterus
Rectouterine pouch - aka pouch of douglas - most inferior point of the peritoneal cavity in females - double fold of peritoneum between the uterus & on to the anterior aspect of the rectum
Describe the peritoneal pouch in males?
Males only have one pouch The vesicorectal pouch - double fold of peritoneum between the bladder and rectum in the males
Big lump in the pic is a tumour in the bladder
Is the peritoneal cavity completely closed in males or females?
The peritoneal cavity is completely closed in males In females it is open due to the uterine tubes opening into the peritoneal cavity as the fimbriae of the tube will sweep the ovum released form the ovary into the cavity into the tube
What aspect of the bladder is in contact with peritoneum? What happens as the bladder fills with urine?
The superior aspect of the bladder is in contact with the peritoneum keeping the bladder stuck to the pubic bones As the bladder fills,, it rises into the suprapubic region however remains covered by its peritoneal lining
If you open the bladder and have a look inside, what are the muscular folds known as? What type of epithelium lines the bladder and why?
The muscular folds inside the bladder are kown as rugae - they are able to stretch allowing for expansion of the bladder The bladder is lined with transitional epithelium which is a stretches easily to accommodate for the fluctuation of volume in an organ. It also helps to protect the bladder from the toxicity of the urine
What is the urachus and where is it located?
The urachus is a fibrous remnant of the allantois - a canal that drains the urinary bladder of the foetus and joins with the umbilical cord at the umbilicus - the urachus is located at the apex of the bladder posterior to the pubic symphysis
When the urachus closes what is it now known as? What does a patent urachus result in?
The urachus is initially open but later closes and forms the median umbiical ligament If the urachus is patent, urine will come out from the umbilicus
Which structure is located at the base of the bladder?
The trigone is a triangular feature located at the base of the bladder
What is the trigone?
The trigone is an internal area of smooth mucous membrane located between the two ureteric orifices and the opening of the urethra
What is the muscular coat of smooth muscle of the bladder known as? What is the muscular coat at the neck of the bladder known as?
Muscular coat of smooth muscle of the bladder is known as the detrusor muscle Smooth muscle encircles the neck of the bladder to form the sphincter vesicae (aka internal urethral sphincter)
Is the sphincter vesicae a voluntary sphincter and is it complete? What is its function?
The sphincter vesicae is an involuntary and incomplete sphincter at the neck of the bladder It helps to regulate the release of urine from the bladder and during ejaculation in a male, it contracts to prevent reflux of semen - what would be known as retrograde ejaculation
What is the neck of the bladder held in place by?
The neck of the bladder is held in place by the pubovesical ligament in females and the puboprostatic ligament in males
What is the approximate length of the urethra in males and females?
The approximate length is 20cm (18-20cm) in males and 4cm in females (3-4cm)
Where does the urethra extend to in females and in males?
In females it extends from the bladder, through the urogenital diaphragm and out through the vagina
In males, it extends from the bladder through the prostate (prostatic urethra), through the urogenital diaphragm (membranous urethra) and travels within the corpus spongiosum (spongy urethra)
What is the arterial supply to the bladder?
The bladder is supplied essentially from the internal iliac vessels
- 2 superior vesical arteries from each side and
- An inferior vesical artery from each side in males which corresponds to the vaginal artery from each side in females
- * What level does the abdominal aorta bifurcate?
- * What level does the common iliac arteries bifurcate?
The internal iliac splits into two major divisions – anterior and posterior division
- * What does the anterior division supply?
- * What does the posterior division supply?
Abdominal aorta bifurcates at L4 into common iliac arteries which bifurcate at L5 into internal and external common iliac arteries The internal iliac artery anterior division supplies the viscera and is regarded as the visceral division The internal iliac artery posterior division is regarded as a parietal division as it supplies most of the body wall
Bladder arterial supply * x2 superior vesical artery from each side * inferior vesical artery from each side in males, vaginal artery from each side in females
What is the venous drainage of the bladder?
What is the nerve supply to the bladder?
Bladder drains to the vesical venous plexus which empties into the internal iliac vein Nerve supply to the bladder is ANS from the inferior hypogastric plexus
The ureters, bladder and urethra all have multiple lymphatic drainage routes What is the lymphatic drainage route of the ureter? How long is the ureter roughly?
Ureter is roughly 25 centimetres long Lymph drains to the lateral aortic nodes (lumbar nodes) when proximal and to the iliac nodes when distal ureter (common, external and internal iliac nodes)
What is the lymphatic drainage of the bladder?
The bladder mainly drains lymph to the internal iliac nodes Some superior bladder drains lymph to the external iliac nodes and some lymph from the neck of the bladder drains to the sacral nodes
State the lymphatic drainage of ureter, bladder and urethra
- Ureter - para-aortic nodes proximally & iliac nodes distally
- Bladder - mainly internal iliac nodes, some superior to external iliac nodes, some neck to sacral nodes
- Urethra - mainly internal iliac nodes, males - spongy urethra to deep inguinal nodes, females - some urethra to sacral nodes
White on pic - pelvis laterally, vertebral posteriorly, urinary calculi in the midline What type of urinary calculi is this?
This is known as a Jackstone - it is a rare bladder stone resembling a toy jack Almost always composed of calcium oxalate dihydrate and consist of a dense central core and radiating spicules
Describe the peritoneal coverings of the rectum?
Describe where the rectum starts and ends?
- Upper 1/3rd of the rectum is covered by visceral peritoneum anterolaterally
- Middle 1/3rd is covered by peritoneum on its anterior surface.
- Lower 1/3rd of the rectum is infraperitoneal
Rectum begins at the 3rd sacral vertebrae and ends 2cm in front of the tip of the coccyx where it pierces the pelvic diaphragm to become the anal canal
The rectum as it descends to become the anal canal essentially is a storage area as you have already absorbed all your water and electrolytes What are the little folds present in the rectum and what do they help create and why?
The three folds present in the rectum are known as the transverse folds - These help to create the rectal ampulla which helps to hold the faeces in the rectum until ready for defecation
Around the base of the rectum is the levator ani
What part of the levator ani slings around the rectum? What is the function of this?
The levator ani is formed from three muscle components -
- * puborectalis
- * pubococcygeus
- * iliococcygeus
Puborectalis slings around the rectum helping to bend the rectum which helps to maintain faecal continence
What is the venous drainage of the rectum? What is the nerve supply to the rectum?
Superior rectum to portal system via inferior mesenteric vein (drains into splenic vein which joins with SMV to form hepatic portal vein)
Middle and inferior rectum to systemic system via internal iliac and internal pudendal vein respectively
ANS from inferior hypogastric plexus
What is the difference in the lymphatic drainage of the anal canal? What line causes the difference?
- Pectinate line - this line divides the upper 2/3rds and lower 1/3rd of the anal canal
- Anal canal superior to the pectinate line drains to the internal iliac nodes
- Anal canal inferior to the pectinate line drains to the superficial inguinal nodes as it is essentially beside the skin
What does the broad ligament extend between? What are the three parts of the broad ligament?
The broad ligament extends between the uterus, the lateral walls and floor of the pelvis
Broad ligament parts
- Mesometrium - largest
- Mesovarium - suspends the ovary within the broad ligament
- Mesosalpinx - this is the broad ligament encasing the uterine tubes
What are the parts of the uterus?
We have the fundus of the uterus lying above the openings of the uterine tubes
We have the body of the uterus
We have the cervix inferiorly opening into the vagina
So uterus has a dual blood supply from the ovarian artery and uterine artery What is the inner narrowing of the uterus known as? What is the widening at the outer aspect of the inferior uterus known as? What exists between these?
- Inner narrowing of the uterus is the internal os
- Widening is the external os
Between these two is the region of the cervix
What are the vaginal fornices?
These are the superior portions of the vagina extending into the recesses created by the cervix
Have an anterior and posterior fornice as well as two lateral fornices
What are the different sections of the uterine tube? Where does fertilization mostly occur?
- We have the isthmus - narrow channels
- Then the ampulla - a widening in the uterine tube
- Just beside the fimbriae is the infundibulum of the uterine tube
Fertilisation usually occurs within the ampulla of the uteirne tube
What investigation can be used to check for the patency of the uterine tubes? Explain the investigation
Hysterosalpinogram - dye is injected into the uterus which allows you to see the shape of the uteus and uterine tubes - the dye should spill out into the peritoneal cavity showing the tubes are patent
In terms of what holds the uterus, there is the broad ligament, round ligament and support from ligaments attached to cervix
We have spoken about the broad ligament and that it carries vessels, nerves and lymphatics
- * What is the round ligament of the uterus a remnant of and where does it travel?
- * What is the potential lymph pathway that this ligament creates?
The round ligament of the uterus is a remnant of the gubernaculum and arises near the opening of the uterine tubes and travels through the deep inguinal ring, within the inguinal canal and through the superficial inguinal ring to attach to the labia major -
- It creates a potential lymph pathway to the superfical inguinal nodes
The inferior portion of the uterus is very strongly held in place by its support from ligaments attached to the cervix Give the names of the three ligaments
- Uterosacral ligament (sacrocervical)
- Transverse cervical ligament (cardinal ligament)
- Pubocervical ligament (pubovesical)
Makes sense for the base of the uterus to be held in place as when a baby is growing the superior uterus will need to expand
What travels within the cardinal ligament of the uterus? Where is the cardinal ligament located?
Within the cardinal ligament of the uterus travels the uterine arteries and veins This ligament is located at the base of the broad ligament
What are the attachments of the uterosacral (sacrocervical), transverse cervical (cardinal) and pubocervical (pubovesical) ligaments?
Uterosacral - from uterus to anterior sacrum
Transverse cervical - from cervix to lateral pelvic wall
Pubocervical - from cervix to pubic symphysis
What do anteverted and anteflexed actually mean?
Anteverted - the long axis of the uterus is bent forward on the long axis of the vagina forming a 90 degree angle
Anteflexed - the long axis of the uterus is bent forward at the internal os forming 170 degree angle between long axis of uterus and long axis of cervix
Ovaries are important for ova and hormone production
How are they attached to the broad ligament?
What is their blood supply, venous drainage and nerve supply?
Attached to the broad ligament via the mesovarium
- Blood supply - ovarian artery from L2 of aorta
- Venous drainage - Right gonadal vein directly to IVC, left gonadal vein to the left renal vein then to IVC
- Nerve - aortic plexus
What ligament from the ovary attaches the ovary to the uterus? What ligament attaches the ovary to the lateral pelvic wall? (What does this ligament carry?
Ligament of the ovary attaches ovary to uterus Suspensory ligament of the ovary carries ovarian vessels and ttaches ovary to lateral pelvic wall
At the very base of the broad ligament there is the ureter What artery does this pass under?
The ureter passes under the uterine artery - water under the bridge In males it passes under the ductus deferens
Describe the lymphatic drainage of the fundus and body of the uterus and uterine tubes and ovaries?
- Uterine tubes, ovaries, most of the fundus of the uterus and superior body all drain back to para-aortic nodes at L2
- Some from the fundus and superior uterus will run on the round ligament to the superficial inguinal nodes
- Broad ligament carries lymph to external iliac nodes for the body
Describe the lymphatic drainage of the uterine cervix?
Vessels from the uterine cervix drain mainly along the uterine vessels to internal iliac nodes although some via the uterosacral ligaments to the sacral nodes and the cervix right beside vagina to the superficial inguinal nodes
