Flashcards in Male Pelvis and Perineum Deck (56)
How is the bulbospongiosus different in females?
The bulb divides around the vestibule to form the vestibular bulbs
Where do the bulbourethral glands open into?
Urethra below the perineal membrane
Where does the rectum receive arteries from?
One pair of arteries from the inferior mesenteric (superior rectal artery)
Two pairs from the internal iliac artery (middle and inferior rectal arteries)
The venous drainage is similar
The rectum is an important site of portal-systemic anastomosis. Which veins are systemic and which are portal?
The venous drainage is similar to the arterial supply. Superior drains into the inferior mesenteric vein and goes to the liver via the portal system. Middle and inferior veins are systemic, and drain into the internal iliac vein.
What is the role of the ischio-anal fossae?
Allows recto-anal and vaginal expansion.
Where is the pudendal neurovascular bundle found?
In the lateral border of the ischio-anal fossa.
Which mass of erectile tissue does the urethra travel through?
Describe the passage of sperm from the seminiferous tubules to the vas deferens.
Seminiferous tubules - rete testis - vasa efferentia (efferent ductules) - head of epididymis - tail of epididymis - ductus deferens
What is another term for foreskin?
What is the term for the ridge of the glans?
Corona of the glans
What is the main branch of the internal iliac artery that supplies the penis?
Internal pudendal artery
What are the arteries and veins that run along the top of the corpora cavernosae and supply the skin and connective tissue?
Dorsal artery of the penis
Where in the tip of the penis can catheters get caught?
Fossa terminalis (navicular fossa)
Which artery supplies the corpora cavernosae?
What makes the penis erect?
Branches supplying the cavernous spaces are usually coiled - helicine arteries
PARASYMPATHETIC stimulation causes dilation of the helicine arteries allowing blood to flow into the penis and cause erection
What nerves supply the pelvic contents? Where do the sympathetic and parasympathetic nerves arise from?
Sympathetic - lower thoracic and upper lumbar - T10-L2 (via the hypogastric plexus)
Parasympathetic - S2-S4
Where is pelvic sensation referred to?
Suprapubic region + perineum
What nerve gives somatic control of some sphincters in the pelvis?
Pudendal nerve (S2-S4)
What does the pudendal nerve provide sensory innervation to and which smaller branch of the pudendal nerve is involved in this?
Sensory - penile skin and glans (via the dorsal nerve of the penis)
What does the pudendal nerve provide motor innervation to?
Perineal muscles - bulbospongiosus and ischiocavernosus
Leads to ejaculation
External urethral sphincter
What are the effects of parasympathetic nerves in the pelvis?
Vasodilation of arterioles in erectile tissue (male and female) leading to erection.
Secretion in prostate and bulbourethral glands
What are the effects of sympathetic nerves in the pelvis?
Contraction of smooth muscles in epididymis, vas deferens, seminal vesicles, prostate during ejaculation
Contraction of internal urethral sphincter (prevents reflux of semen)
What does the pudendal nerve supply?
All the perineal muscles
Which plexus do the somatic nerves leave the pelvis from?
Which arteries relax to allow blood flow into the penis?
Internal pudendal artery