hello all this is dr alsup and in this video we are going to focus on the basic spatial
arrangement of viscera in the pelvic cavity and the peritoneal arrangement within so how
does that inferior most extent of the parietal peritoneum actually drape over the pelvic viscera
but let's start with the arrangement of the internal pelvic viscera
and oftentimes when discussing internal pelvic viscera or identifying structures
we look at a sagittal section of the pelvis so the internal portion of that sagittal section
often we just refer to this as a hemisection of the pelvis and this is a deliberate choice because
it is often difficult to view all internal pelvic structures particularly the deeper structures
from a superior view so if you think kind of looking down into this region you wouldn't be able
to see a lot of the more inferior structures so a hemisection is kind of key for that so many of the
BlueLink image images and the illustrations that we will use are going to be in this
hemisection view the internal pelvic viscera can be divided into three major systems the urinary
the reproductive and associated endocrine systems as well as of course the gastrointestinal system
and they are mostly organized in this same order from anterior to posterior with some
of the reproductive organs being better described as inferior rather than intermediate emplacement
so urinary system viscera tend to be more anteriorly placed with the urinary bladder being
located just posterior to the pubic symphysis so here's the pubic symphysis on this image
on this image and here is the bladder in both of these images and of course you also
have those distal ureters that are going to be entering the bladder on its posterior surface
reproductive viscera tend to be more intermediate in placement in the pelvic cavity particularly
in the case of the uterus as well as the uterine tubes and ovaries you can see a bit of the tube
here and the ovaries here oftentimes these can be described as intermediate and superior
the vagina is going to be more intermediately placed you will also have the seminal glands
as well as the ductus deferens or the vas deferens that can be described as more intermediately
placed the prostate and the bulbourethral glands may be better described as more inferiorly placed
particularly in comparison to the bladder the distal portions of the gastrointestinal system
are more posteriorly placed and this will include the distal sigmoid colon as well as the rectum
which is going to be prominent in the pelvic cavity region and then the anal canal will
be more um into this region here so a little bit inferiorly as well but posterior inferior for sure
now let's discuss uh in let's discuss peritoneum and i know you likely have had your fill of
peritoneal discussions during the gastrointestinal portion of the curriculum but it's very pertinent
here as well the parietal peritoneum will continue inferiorly into the pelvic cavity so you can
kind of this kind of white outline right here is giving you an indication of that inferior extent
into the pelvic cavity region now importantly the peritoneum does not
reach the pelvic floor or the pelvic diaphragm region instead it reflects onto the pelvic viscera
and those areas where peritoneum reflects from one portion of viscera to another creates what we call
peritoneal pouches and dependent on the viscera present in an individual there will either be one
pouch or two and it is the presence of the uterus that will create two pouches the pouch between
the bladder and the uterus so you can kind of see that extent right here
is referred to as the physical uterine pouch this pouch is considerably shallower than
the recto uterine pouch which is in this general region right here
that medium portion of the rectal uterine pouch is generally considered the most
inferior extent of the peritoneal cavity and i want you to note right here the
close relationship of the rectouterine pouch and the posterior vaginal fornix so recall that
recess of the vagina from where the cervix kind of moves into this region
so you have a very close relationship here with the the vaginal fornix and the
the inferior extent of the peritoneum and if say there is a pelvic abscess in the recto uterine
pouch this area can be drained through making a small incision in the posterior vaginal fornix
region and this is referred to as a culdocentesis as you can see written here oops excuse me
now without the presence of the uterus there is one peritoneal pouch
where the peritoneum reflects from the bladder to the rectum and in this particular image
the bladder is very distended so it's not typically this large
but that pouch in between the two or kind of where that reflection occurs is the rectovesicle pouch
here you can really see because this is the inferior most extent how the
inferior third of the rectum is below the peritoneum and thus referred to as subperitoneal
all right excellent i hope you are beginning to feel comfortable with the basic spatial
relationships of the internal pelvic viscera we will talk about each and every one of the
the viscera that we discussed in a bit more detail in upcoming videos so stay tuned for those
thank you for your time and attention here and i hope you have a great rest of your day