Flashcards in Male Pelvis and Perineum Deck (56)
State some differences between the male pelvis and the female pelvis?
The pelvic inlet is more oval shaped and round in females, it is heart shaped and narrower in males
Females - ischial spines do NOT point medially, in males they do
Females - sub-pubic angle > 80 degrees, males 50-60 degrees
Females - ratio of distance between the pubic symphysis and the anterior margin of the acetabulum is 1 or > 1, in men it is < 1.
Females - true pelvis is shallow, wide and cyllindrical, males it is deep, narrow and tapers
Females - false pelvis is wide, males it is narrow
Describe the orientation of the pelvic girdle with reference to two bony landmarks that are in the same plane.
ASIS and pubic tubercle are in the same vertical plane
True or False: the parietal peritoneum reaches the pelvic floor.
False - the parietal peritoneum does NOT reach the pelvic floor
What is found in the space between parietal peritoneum and pelvic wall that is not occupied by viscera?
What are the ligaments that support pelvic viscera made up of?
Pelvic fascial condensations
Describe the path of the ductus deferens from the epididymis to the urethra.
The ductus deferens goes in through the superficial inguinal ring, through the inguinal canal and out of the deep inguinal ring. It then goes superior to the bladder, crosses the ureter and goes posterior to the ureter and joins the urethra through the prostate. Before joining the urethra, the ductus deferens joins with the seminal vesicle to form the ejaculatory duct which then joins the urethra in the prostate.
What structures can be felt in a DRE of a healthy man?
Prostate and seminal vesicles. Probably not the bladder unless there is something abnormal.
What are the four parts of the urethra? State how long they are.
Pre-prostatic - 1.5 cm
Prostatic - 2.5 cm
Membranous - 2 cm
Spongy - 15 cm
(sometimes the parts are: prostatic, bulbar, membranous and spongy)
What glands are found within the urogenital diaphragm and where do these glands open into?
Bulbourethral Gland (produces secretions that lubricate the urethra and provide nutrients
What is the ampulla of the ductus deferens?
This is a dilation that is found just before the joining of the ductus deferens with the seminal vesicle to form the ejaculatory duct.
What three components empty into the prostatic urethra?
How many ejaculatory ducts are there?
2 - there are two vas deferens' as well because there are two testicles
What is the cul-de-sac in the prostatic urethra is a site where a catheter could get lodged?
Describe the internal urethral sphincter.
Made up of smooth muscle and is well organised in males (but not so well organised in females). It is under sympathetic control.
What happens to this sphincter during ejaculation?
It closes due to sympathetic stimulation. Parasympathetic stimulation makes it open.
State three areas of narrowing of the urethra for the navigation of a catheter.
External urethral orifice (narrowest part)
90 degree turning of the urethra in the membranous part
What large blood vessel is involved in supplying the pelvis and its contents?
Internal iliac artery
What are the two main branches of this artery?
Anterior and posterior branches
What are the main divisions of the anterior branch of the internal iliac artery?
Anterior branch is mainly concerned with supplying the pelvic viscera
Superior and Inferior vesical arteries (superior = bladder + ductus deferens/ inferior = PROSTATE + blader + ductus deferens)
Prostate is supplied by the prostatic branch of the inferior vesical artery.
Other branches include the obturatory artery and the internal pudendal artery
What does the posterior branch of the internal iliac artery supply?
Gluteal muscles (you get superior and inferior gluteal arteries)
Where do the testes receive their blood supply from?
Testicular arteries - branch off the abdominal aorta below the renal arteries
What are the borders/apices of the male perineum?
What can the perineum be divided into?
Anterior - urogenital triangle
Posterior - anal triangle
What are the fat-filled spaces that separate the anal canal and the levator ani from the pelvic walls?
How can the anterior triangle be further divided?
It is divided into SUPERFICIAL and DEEP POUCHES by the PERINEAL MEMBRANE
What is the perineal membrane?
Thick triangular fascial structure attached to the pubic arch and extending between the ischiopubic rami. Posteriorly free margin
What are the two potential spaces related to the perineal membrane?
Superficial and deep perineal spaces
What regions of erectile tissue that make up the penis?
Corpora cavernosae (paired muscles)
REMEMBER: erectile tissue within the perineum is surrounded by skeletal muscles.
What muscle is associated with the corpus cavernosum? Where does it attach?
Ischiocarvernosus - attaches to the ischiopubic ramus
What muscle is associated with the bulb of the penis/corpus spongiosum?
Bulbospongiosus - this is midline and attached to the perineal membrane