Female perineum Flashcards
Summarise the perineal spaces (or pouches)
Perineal membrane (PM): Thick triangular fascial structure attached to pubic arch. Posterioly free margin. Anteriorly a small gap.
Deep perineal space: is above the PM and below fascia of pelvic diaphragm.
Superficial perineal space: is below PM and perineal fascia (subcutaneous tissue)
These spaces are potential spaces and they become real only when for eg: fluid leaks into them
What is the mons pubis
the fatty tissue anterior to the pubic symphysis, covered by hairy skin, continues posteriorly on each side of the vaginal opening as the labia majora
List the muscles in the deep perineal pouch in females
external urethral sphincter- as in men - Compress the membranous urethra as internal sphincter less well developed in females
deep transverse perineal- as in men
compressor urethrae
sphincter urethrovaginalis
Describe the compressor urethrae
arises from the ischiopubic ramus on each side
blends with partner on the other side anterior to the urethra
innervated by perineal branches of the pudendal nerve (S2-S4)
functions as the accessory sphincter of urethra
Describe the sphincter urethrovaginalis
arises from the perineal body and passes forward to the vagina to blend with its partner on other side anterior to the urethra
innervated by the perineal branch of the pudendal nerve (S2-S4)
Functions as an accessory sphincter of the urethra (also may facilitate closing the vagina)
Describe the importance of the perineal body
Ill-defined but important connective tissue structure into which muscles of the pelvic floor and the perineum attach
It is positioned in the midline along the posterior border of the perineal membrane, to which it attaches
the posterior end of the urogenital hiatus in the levator ani muscles is also connected to it.
The deep transverse perineal muscles intersect at the perineal body; in women, the sphincter urethrovaginalis also attaches in the perineal body. Other muscles that connect to the perineal body include the external anal sphincter, the superficial transverse perineal muscles, and the bulbospongious muscles of the perineum
Summarise the contents of the superficial perineal pouch in women
Median erectile tissue masses (corpus spongiosum) In females it divides around the vestibule to form vestibular bulbs. The glans of clitoris is derived from this.
Lateral erectile tissue masses (corpora cavernosa) Paired cylinders, attached to ischiopubic rami. The body of clitoris is derived from these.
These erectile tissues within perineum are surrounded by skeletal muscles
List the contents of the superficial perineal pouch in females
Vulva = collective name for female external genitalia: mons pubis, labia majora & minora, clitoris, vestibule of vagina, vestibular bulbs, vestibular glands
Summarise the perineal membrane in females
As in the male, the perineal membrane fills the urogenital triangle. The erectile tissues and associated skeletal muscles are anchored to this.
Describe the erectile tissue in females
In women a pair of erectile structures, termed the bulbs of vestibule, are situated, one on each side, at the vaginal opening and are firmly anchored to the perineal membrane,
Small bands of connective tissue connect the anterior ends of these bulbs to a single, small, pea-shaped erectile mass, the glans clitoris, which is positioned in the midline at the end of the body o the clitoris and anterior to the opening of the urethra.
Describe the clitoris
Composed of two corpora cavernosa and the gland clitoris
As in the penis it has an attached part (root) and a free part (body)
Unlike the root of the penis, the root of the clitoris technically consist only of the two crura (although the bulbs of the vestibule are attached to the glans clitoris by thin bands of erectile tissue, they are not included in the attached part of the clitoris
the body of the clitoris, which is formed only by the unattached parts of the two corpora cavernosa, angles posteriorly and is embedded in the connective tissue of the perineum
What is the body of the clitoris supported by
A suspensory ligament that attaches superiorly to the pubic symphysis.
The glans clitoris is attached to the distal end of the body and is connected to the bulbs of the vestibule by small bands of erectile tissue
The glans clitoris is exposed in the perineum and the the body of the clitoris can be palpated through skin
Describe the superficial features of external genitalia in females
In women, the clitoris and vestibular apparatus, together with a number of skin and tissue folds, form the vulva
On either side of the midline are two thin fold of skin, termed the labia minora
The region between them and into which the urethra and vagina open is the vestibule
Describe the labia minora
Anteriorly, they bifurcate, forming a medial and lateral fold
medial forms unite to form the frenulum of the clitoris, that joins the glans clitoris
the lateral folds unite ventrally over the glans clitoris and body of clitoris to form the prepuce of clitoris (hood)
posterior to the vestibule, the labia minora unite, forming a small transverse fold, the frenulum of the labia mnora (the fourchette)
lateral to the labia minora are two broad fold, the labia majora, which unite anteriorly to form the mons pubis
What is found in the vestibule
The vaginal orifice is surrounded by varying degrees of a ring-like fold of membrane, the hymen, which may have a central perforation or may completely close the vaginal opening
Following rupture of the hymen (resulting from first sexual intercourse or injury), irregular remnants of the hymen fringe the vaginal opening