Anatomy 5: Urinary Incontinence and Prolapse Flashcards
What are the 3 components which made up the pelvic floor?
Pelvic diaphragm
Muscles of perineal pouches
Perineal membrane
What are the two groups of muscles which make up the pelvic diaphragm?
Levator ani
Coccygeus
What passes through the pelvic diaphragm?
Urogenital hiatus
Passage for urethra and vagina
What are the 3 parts of the levator ani?
Puborectalis
Pubococcygeus
Iliococcygeus
Where does the Levator Ani attach?
- Pubic bones, ischial spines and tendinous arch of levator ani
- Perineal body, coccyx and walls or organs in midline
What innervates the levator ani?
Pudendal nerve (S2,3,4) Nerve to Levator Ani (S3,4,5)
What are the supporting ligaments/fascia of the pelvic organs?
Endo-pelvic fascia
Pelvic ligaments
What are the Pelvic Ligaments?
- Fibrous Endo-pelvic fascia
- Uterosacral
- Transverse cervical
- Lateral ligament of bladder
- Lateral rectal ligament
Where is the deep perineal pouch?
Lies below the fascia covering the inferior aspect of the pelvic diaphragm
Lies above the perineal membrane
What does the Deep Perineal Pouch contain?
- Part of the urethra (and vagina in females)
- Bulbourethral glands in males
- Neuromuscular bundle for penis/clitoris
- Extensions of the ischioanal fat pads and muscles
What is the difference between the deep transverse perineal muscle in the males and females?
In males there is the bulbourethral gland
In females, just smooth muscle
Where is the location of the perineal membrane?
Superficial to the deep perineal pouch
Thin sheet of tough, deep facia
Attaches laterally to the sides of the pubic arch, closing the urogenital triangle
What are the features of the Perineal Membrane?
Opening for the urethra (and vagina in females)
Together with the perineal body, it is the last passive support of the pelvic organs)
Where is the location of the superficial Perineal Pouch?
-Lies below the perineal membrane
What makes up the superficial perineal pouch in males?
Contains the root of the penis:
- Bulb (corpus spongiosum and corpus cavernousum)
- Associated muscles (bulbospongiosus and ischiocavernosus)
What makes up the superficial perineal pouch in females?
Contains female erectile tissue and associated membrane:
- Clitoris and Crura (corpus cavernosum)
- Bulbs of vestibule (paired)
- Associated muscles: bulbospongiosus and ischiocavernosus
What 3 factors does urinary incontinence depend on?
- Urinary bladder neck support
- External urethral sphincter
- Smooth muscle in urethral wall
How can prolapse be repaired surgically?
Sacrospinous fixation
Incontinence surgery
What is sacrospinous fixation?
- Sutures placed in sacrospinous ligament
- Just medial to the ischial spine
- To repair cervical/vault descent
- Performed vaginally
- Risk of injury to pudendal NVB and sciatic nerve
What is incontinence surgery?
- Trans-obturator approach
- Mesh through obturator canal
- Create a sling around the urethra
- Incisions through vagina and groin
What is the nerve roots of the detrusor muscle?
Supplied primarily by parasympathetic nerves derived from pelvic splanchnic nerves S2,3,4
What is the nerve roots the urethral smooth muscle?
Supplied primarily by sympathetic nerves derived from spinal cord at T10-L2
What predominates during bladder filling- sympathetic or parasympathetic?
Sympathetic to allow bladder muscle to relax
At what ml is there usually a desire to micturate?
About 400mls
What happens in the voiding stage?
- The parasympathetic supply (via the pelvic Splanchnic nerves S2,3,4) causes detrusor contraction and urine enters the urethra
- The pudendal nerve (S2,3,4) ensures relaxation of the external urethral sphincter and pelvic floor
How is the micturition reflex initiated?
The sense of urine in the urethra is via the pudendal nerve
What does the term “vulva” relate to?
The collective name given to the female urogenital triangle structures: the mons pubis, labia majora, labia minora, vestibule, vaginal orfice, orfices of the vestibular glands and clitoris
