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Pelvic Viscera
Viscera
Gastrointestinal
The main gastrointestinal contents housed in the pelvic cavity are the rectum and
anal canal, however, the distal portion of the sigmoid colon is also located here.
The Rectum
Continuous with the sigmoid colon at the level of S3
Continuous with the anal canal distally when it penetrates the pelvic floor and
ends as the anus
The rectum is the most posterior part of the pelvic viscera and is found immediately
anterior to the sacrum. It follows the contour of the sacrum. The anorectal junction is
pulled forward by the action of the puborectalis muscle
The rectum has 3 curvatures, the upper and lower ones to the right and a middle
curvature to the left.
The distal part of the rectum is expanded into the rectal ampulla.
Pelvic Viscera 1
, The Anal Canal
Begins at the distal part of the rectal ampulla, where it narrows at the pelvic floor.
It terminates as the anus after passing through the perineum.
As this canal passes through the floor, it is surrounded by internal and external
anal sphincters which normally keep it closed.
The proximal part of the anal canal is lined by mucosa similar to that of the
rectum and is distinguished by a number of longitudinal folds called the anal
columns. These anal columns are united with other folds inferiorly called anal
valves which are crescent-shaped.
The anal valves create anal sinuses superior to them and collectively form a
circle known as the pectinate line.
The anal pecten is the transition zone inferior to the pectinate line that
contains non-keratinized squamous epithelial cells.
Pelvic Viscera 2
, Urinary System
Ureters
The ureters enter the pelvic cavity from the abdomen by passing through the pelvic
inlet. These pass into the pelvic cavity by crossing anterior to the bifurcation of the
common iliac arteries. From this point, each ureter continues along the pelvic wall
and floor to terminate at the base of the bladder.
The ureter is crossed by the ductus deferens in males
The ureter is crossed by the uterine artery in females.
Pelvic Viscera 3
Pelvic Viscera
Viscera
Gastrointestinal
The main gastrointestinal contents housed in the pelvic cavity are the rectum and
anal canal, however, the distal portion of the sigmoid colon is also located here.
The Rectum
Continuous with the sigmoid colon at the level of S3
Continuous with the anal canal distally when it penetrates the pelvic floor and
ends as the anus
The rectum is the most posterior part of the pelvic viscera and is found immediately
anterior to the sacrum. It follows the contour of the sacrum. The anorectal junction is
pulled forward by the action of the puborectalis muscle
The rectum has 3 curvatures, the upper and lower ones to the right and a middle
curvature to the left.
The distal part of the rectum is expanded into the rectal ampulla.
Pelvic Viscera 1
, The Anal Canal
Begins at the distal part of the rectal ampulla, where it narrows at the pelvic floor.
It terminates as the anus after passing through the perineum.
As this canal passes through the floor, it is surrounded by internal and external
anal sphincters which normally keep it closed.
The proximal part of the anal canal is lined by mucosa similar to that of the
rectum and is distinguished by a number of longitudinal folds called the anal
columns. These anal columns are united with other folds inferiorly called anal
valves which are crescent-shaped.
The anal valves create anal sinuses superior to them and collectively form a
circle known as the pectinate line.
The anal pecten is the transition zone inferior to the pectinate line that
contains non-keratinized squamous epithelial cells.
Pelvic Viscera 2
, Urinary System
Ureters
The ureters enter the pelvic cavity from the abdomen by passing through the pelvic
inlet. These pass into the pelvic cavity by crossing anterior to the bifurcation of the
common iliac arteries. From this point, each ureter continues along the pelvic wall
and floor to terminate at the base of the bladder.
The ureter is crossed by the ductus deferens in males
The ureter is crossed by the uterine artery in females.
Pelvic Viscera 3
