pelvis, perineum week 10 Flashcards
What is the perineum
the external surface area of the region overlying the pelvic outlet (also refers to the compartment
It is separated from the pelvic cavity from the diaphragm
What shape is the perineum?
diamond shaped when legs abducted
What structures can you see on the perineum?
Mons pubis
Medial aspect of the thighs laterally
Gluteal folds and upper end of the intergluteal cleft posteriorly
What is the mons pubis?
A mound of fatty tissue overlying the pubic symphysis
What are the ossifiborous structures that form the perineum
Pubic symphysis (anteriorly
inferior pubic ramus (anteriolaterally)
Ischial rami (anteriolaterally)
Ischial tuberosities (laterally)
Sacrotuberous ligaments (posteriolaterally)
Inferior aspect of the sacrum and coccyx (posteriorly)
What are the two triangles of the perineum
Posterior region (anal region or anal triangle) Anterior region (Urogenital region or urogenital triangle)
Where does the urogenital region stretch from?
the root of the scrotum and penis/ external female genitalia
What is the perineal body?
The midpoint of the line between the ischial tuberosities
is an irregular fiborous mass
contain collagenous and elastic fibres as well as skeletal and smooth muscle
Where oes the perineal body lie?
posterior to the bulb of the penis, anterior to the anus and anal canal
what attaches to the posterior border of the perineal membrane?
Perineal body
Bulbospngiosis
External anal sphincter
Superficial and deep transverse perineal muscles
What is the anal canal?
the terminal part of the bowel (2.5-3.5 cm long)
Begins where the puborectalis muscle forms a sling around the end of the rectum
Runs between the upper aspect of the pelvic diaphragm to the anus
What is the external anal sphincter?
Large voluntary band of muscle and are found on either side of the anal canal
Blend with the puborectalis muscle
supplied largely by the S4 inferior rectal nerve
What is the internal anal sphincter?
An involuntary muscle band that surround the superior 2/3 of the anal canal
is a thickening of the muscle within the bowel
Supplied by parasympathetic nerve fibres from pelvic splanchnic nerves
What are the 3 germ layers?
Endoderm
Mesoderm
Ectoderm
What makes up the pelvic diaphragm?
levator ani
coccygeus
fascia