Week 5 - Anatomy of Incontinence and Prolapse Flashcards
The pelvic floor separates what structures?
The pelvic cavity and the perineum
The pelvic floor has what two important roles?
Provides support to pelvic organs, and maintains continence
What are the 3 components of the pelvic floor?
Perineal membrane, muscles of perineal pouches and the pelvic diaphragm
Deep and superficial perineal pouches are broken up by what structure?
The perineal membrane
What is the deepest layer of the pelvic floor?
Pelvic diaphragm
What does the pelvic diaphragm consist of?
The levator ani and coccygeus
There is an anterior gap between the medial borders of the pelvic diaphragm. This is known as what?
The urogenital hiatus
There is an anterior gap between the medial borders of the pelvic diaphragm. This allows the passage of what structure(s) in males?
The urethra
There is an anterior gap between the medial borders of the pelvic diaphragm. This allows the passage of what structure(s) in females?
The urethra and vagina
What structures form the dynamic pelvic floor?
Levator ani and coccygeus
Which muscle forms the majority of the pelvic diaphragm?
The levator ani
What are the 3 parts of the levator ani?
Puborectalis, pubococcygeus and iliococcygeus
Which one of the 3 components of the levator ani is not a true sling since it has a break in the muscle fibres?
Pubococcygeus
The pelvic floor reflexively contracts when?
In situations of raised intra-abdominal pressure
The levator ani spends most of its time in what state?
Tonically contracted
To allow urination and defaecation, the levator ani muscle must do what?
Relax
What is the innervation to the levator ani?
The pudendal nerve (S2, 3, 4) and nerve to levator ani (S3, 4, 5)
The iliococcygeus overlies what structure?
Obturator foramen
Which specific part of the levator ani is responsible for faecal continence?
Puborectalis
As well as the pelvic floor, what other structures provide additional support for the pelvic organs?
Endopelvic fascia and pelvic ligaments
Fibrous endopelvic fascia forms what?
Pelvic ligaments
The deep perineal pouch lies below what?
The fascia covering the inferior aspect of the pelvic diaphragm
The deep perineal pouch lies above what?
The perineal membrane
What is the muscle of the deep perineal pouch which is present in both males and females?
Compressor urethrae
What is the muscle of the deep perineal pouch which is only present in males? What type of muscle is this composed of?
Deep transverse perineal muscle - skeletal
The female equivalent of the deep transverse perineal muscle is not named. What type of muscle is it formed of?
Smooth
The perineal membrane lies where is relation to the deep perineal pouch?
Superficial
What is the perineal membrane?
A thin sheet of tough, deep fascia
The perineal membrane attaches laterally to the sides of what structure? It closes what triangle?
The pubic arch / the urogenital triangle
The perineal membrane comprises openings for which structures?
The urethra (and vagina in females)
The perineal membrane, along with the perineal body, is the last passive support of the pelvic organs. What is meant by this?
Everything superficial to this structure will be dynamic, i.e. it will move
The superficial perineal pouch lies below (i.e. superficial) to what structure?
The perineal membrane
Within the superficial perineal pouch, what forms the bulb of the penis?
The corpus spongiosum
Within the superficial perineal pouch, what forms the crura of the penis?
The corpus cavernosum
What are the muscles of the root of the penis which are found within the superficial perineal pouch?
The bulbospongiosus and ischiocavernosus
What is the function of the bulbospongiosus muscle?
Rhythmically contracts to cause ejaculation
What neurovascular structures lie within the superficial perineal pouch?
Pudendal nerve and internal pudendal vessels (specifically superficial perineal nerve)
The Bartholin’s gland is found within which aspect of the pelvic floor?
Superficial perineal pouch
Which muscles of the pelvic floor are most responsible for maintaining urinary continence?
External urethral sphincter, compressor urethrae and levator ani
