9. The pelvic floor Flashcards
name the 2 muscular layers forming the pelvic floor, and their constituents
- pelvic diaphragm (supportive ‘cup’ attaching to lesser pelvis and separating pelvic cavity from perineum)
- levator ani: pubococcygeus, puborectalis and iliococcygeus
- coccygeus - perineum (fibromuscular ‘saucer’ centred around perineal body)
Deep layer:
- compressor urethrae and external urethral sphincter
- deep transverse perineal
Superficial layer:
- bulbospongiosus and ischiocavernosus (superficial perineal pouch)
- external anal sphincter
- superficial transverse perineal
which nerve supplies most of the pelvic floor musculature to maintain tone
pudendal n. (S2-4)
name 3 pelvic floor muscles important in maintaining faecal continence
Voluntary:
- Puborectalis - maintains 80° anorectal flexure at anorectal junction
- External anal sphincter - constricts anal canal during peristalsis, resisting defecation; supports and fixes perineal body/pelvic floor
Involuntary:
- Internal anal sphincter - smooth muscle (sup. 2/3 anal canal) maintaining continuous muscle tone (sympathetic) to prevent fluid/flatus leakage
name and label this muscular layer
pelvic diaphragm
name and label this muscular layer
perineum
which nerve and spinal cord segment is responsible for external anal sphincter contraction
inferior anal n.
S4
describe the osseofibrous boundaries of the perineum
- anterior: pubic symphysis
- anterolateral: inferior pubic and ischial rami
- lateral: ischial tuberosities
- posterolateral: sacrotuberous ligaments
- posterior: inferior-most sacrum and coccyx
describe the 2 triangles of the perineum
transverse line between 2 ischial tuberositis separates:
- anal triangle
- contains anal canal and anus - urogenital triangle
- contains root of scrotum and penis or vulva
- has additional layer of tough deep fascia: perineal membrane, perforated bu urethra and vagina
what is the function of ther perineal body in women
tear-resistant body between vagina and external anal sphincter - supports posterior part of vaginal wall against prolapse
dysfunction of pelvic floor results in which type of urimary problem
stress incontinence
describe 4 different types of pelvic organ prolapse
- CYSTOCOELE: anterior wall prolapse - bladder bulges into anterior vaginal wall
- UTERINE PROLAPSE: prolapse of uterus and cervix, or top of vagina
- VAGINAL VAULT PROLAPSE: prolapse of vagina apex after hysterectomy
- Posterior wall prolapse: RECTOCOELE - rectum bulges into posterior vaginal wall; or ENTEROCOELE - loops of bowel prolapse into rectovaginal space/Pouch of Douglas
name 6 risk factors for pelvic organ prolapse
- increasing age
- vaginal delivery (4x increased after 1 delivery, 11x increased after 4 deliveries)
- post-menopausal oestrogen deficiency
- obesity and causes of chronic raised intra-abdominal pressure
- neurological, e.g. spina bifida, muscular dystrophy
- genetic CT disorders, e.g. Marfan’s, Ehlers Danlos
describe the management options for pelvic floor prolapse
- pelvic floor exercises
- pessaries (ring, shelf or gelhorn)
- surgical management (risk of recurrence and possible complications)
name these types of prolapse
which levator ani muscles and nerves of pelvic floor are at particular risk of damage during childbirth
- pubococcygeus and puborectalis
- pudendal n.
describe the 4 degrees of perineal trauma
- 1st degree tear: laceration of vaginal epithelium or perineal skin only
- 2nd degree tear: involvement of perineal muscles, but not anal sphincter
- 3rd degree tear: involvement of anal spincter but not anal mucosa
- 4th degree tear: involvement of anal sphincter and anal mucosa
which procedure can be used to try and prevent OASIS (obstetric anal sphincter injuries) and in which cases is it recommended
- mediolateral episiotomy: 45-60 degree angle from midline to prevent tearing of perineal body
- intstrumental deliver, large baby, shoulder dystocia
describe the 4 different types of FGM
- CLITORIDECTOMY: partial or total removal of clitoris or prepuce
- EXCISION: partial or total removal of clitoris and labia minora, +/- excision of labia majora
- INFIBULATION: narrowing of the vaginal orifice with creation of a covering seal by cutting and apposition of labia minora and/or labia majora, +/- clitoridectomy
- All other harmful procedures to the female genitalia for non-medical purposes, eg pricking, piercing…
