Pelvic Organs Flashcards
Name the pelvic portions of the tubular G.I.T.
Sigmoid colon, rectum and anal canal.
Where does the rectum begin?
Mid sacral level. At pelvic brim
What is the ampulla of the rectum?
The dilated portion of the rectum where fecal matter is stored before elimination
What is the anorectal angle?
The region of the rectum that passes through the pelvic diaphragm. The puborectalis muscle passes posterior to the rectum here. it loops around and when contracted draws the rectum anteriorly causing the tube to fold
What are transverse folds?
3 mucosal folds that pass 2/3 of the way around the circumference of the rectum in a staggered array. They characterize the lumen of the rectum
Describe the blood supply to the rectum.
Upper = superior rectal via the inferior mesenteric; middle and lower = branches of the internal iliac
The inferior rectal arteries off of the internal pudendal arteries are in the ischioanal fossa and provide blood to the anal canal
How is the rectum innervated?
It is mostly smooth muscle and innervated by predominately parasympathetic visceral motor fibers and visceral AFFERENT fibers
Describe the venous drainage of the rectum?
Superior rectal vv. drains into the portal system (inf. mesenteric v.); middle and lower rectal vv. drain to the systemic system via the inferior vena cava.
What do hemorrhoids indicate?
A blockage in either the portal or systemic systems causing blood to back up into these portocaval anastomoses of the rectum/anal canal.
Name two peritoneal-lined recesses within the pelvis in the female.
Vesicouterine and rectouterine pouches.
How many peritoneal-lined recesses are there in the male? Name them.
One - the rectovesical.
Where do the ureters become pelvic?
As they cross the bifurcation of the common iliac into the internal and external iliac aa. at the pelvic brim.
Why is this association clinically important in the female?
During hysterectomy (removal of the uterus) the ureter might be tied off instead of or in addition to the uterine artery.
What structure crosses the pelvic ureter in the male? in the female?
The ductus deferens in the male; the uterine artery in the female. They both cross superior to the ureter… Bridge over water
What is the triangular smooth area on the wall of the bladder called?
The trigone.
How do the ureters enter of the bladder and why?
They enter at oblique angle in the posterior surface of the bladder so that urine does not backflow
What structures delineate this triangle?
The upper two corners are the entrance of the ureters into the bladder, the lower corner is the exit of the urethra from the bladder.
What is the function of the 2 divisions of the autonomic nervous system in the bladder?
Parasympathetic: motor to smooth muscle (detrusor m.) of the bladder, inhibitory to the sphincter vesicae. Off pelvic splanchnic S2 S3 S4
sympathetic: have antagonistic actions. Innervate the sphincter vesicae from Prevertebral abdominal ganglion and is contracted during bladder filling and ejaculation (so no urination)
(98% is detrusor–para, 2% is sphincter–symp_
What is the function of the 2 divisions of the autonomic nervous system in the bladder?
Parasympathetic: motor to smooth muscle (detrusor m.) of the bladder, inhibitory to the sphincter vesicae. Off pelvic splanchnic S2 S3 S4
sympathetic: have antagonistic actions. Innervate the sphincter vesicae from Prevertebral abdominal ganglion and is contracted during bladder filling and ejaculation (so no urination)
What are the 3 portions of the male urethra?
Prostatic, membranous and spongy (penile). spongy terminates at the external urethral opening to form the navicular fossa and also bulbourethral glands open into the proximal portion
Which part is clinically important during catheterization? Why?
The membranous as it is the least supported by surrounding structures, is found at the turn of the penile urethra up to the prostatic urethra and is the most easily penetrated during catheterization.
Be able to label the various portions on a sagittal section through the pelvis.
This diagram is important (page 241) as well as superimposing the contents of the scrotum and their anatomy on this diagram.
What is delivered via the ejaculatory ducts?
Spermatozoa from the testis and seminal fluid from the seminal vesicles.
What is delivered via the prostatic ducts?
Prostatic fluid.
What is the function of the epididymis?
The epipidymis functions as a place to store sperm prior to ejaculation and where it typically becomes fully mature (finish the maturation process) during this storage phase.
