4. Clinical anatomy of the pelvic floor Flashcards
What are the functions of the pelvic floor?
- Support pelvic organs
- Continence
- Passing of urine and faeces
- Breathing
- Sexual function
- Pregnancy and Childbirth
- Maintain intraabdominal pressure
What are the 3 mechanisms of support?
Suspension, attachment, fusion
What is suspension support?
Strong vertical support working against gravity, mainly by 3 ligaments.
Which 3 ligaments are involved in suspension support?
Cardinal, uterosacral and round ligament
What is the function of the cardinal ligaments?
Attach the cervix and upper vagina to the lateral pelvic wall, at the level of the ischial spines, to hold it in place
What is the function of the uterosacral ligaments?
Attach the cervix and upper vagina to the sacrum, to hold it in place
What is the function of the Pubocervical Ligaments?
Attach the cervix to the posterior surface of the pubic symphysis. They function to support the uterus within the pelvic cavity.
What is the functions of the round ligament?
Maintain the anteverted position of the uterus
What is attachment support?
Support that comes from attachments on the pelvic
organs
What is attachment support provided by? (4)
Arcus tendinous fascia pelvis (white line), endopelvic fascia, levator ani muscles, perineal body
What is the arcus tendinous fascia and what is its function?
Thickening of the lateral parts of the pubocervical fascia (part of the ednopelvic fascia), attaches from pubic tubercle to ischial spine. Provides supportive attachment for visceral pelvic fascia, lining the urogenital organs.
What is the endopelvic fascia and what is its function?
Fascia which sits inferiorly to the pelvic peritoneum. Support urogenital organs and maintains their positions.
How does endopelvic fascia help to maintain urinary continence?
Urethra lies anterior and above it, and so gets compressed during increased intra-abdominal pressure
What is fusion support?
Support that arises from fusion of different tissues
What structures are involved in fusion support?
Involves fusion of the urogenital diaphragm and the perineal body etc.
What is the lower half of the vagina supported by?
By fusion of the vaginal endopelvic fascia with the perineal body posteriorly, levator ani muscles laterally and the urethra anteriorly.
What is the pelvic floor composed of?
Deep muscles (Levator ani), superficial muscles (perineal muscles), perineal body, urogenital diaphragm,
What are the levator ani muscles and what are their functions?
These deep muscles are a U-shaped set of muscles that act like a sling, to encircle the urethra, vagina and rectum, and provide support for these organs.
What are the different levator ani muscles?
Puborectalis, Pubococcygeus, iliococcygeus muscles
What structures do the levator ani muscles encircle?
The urethra, vagina and the rectum
What are the origins of the levator ani muscles?
Posterior surface of body of pubis, tendinous arch of levator ani and medial aspect of ischial spines
What is the tendinous arch of levator ani?
A thickening of the fascia of the obturator internus that attaches from pubis bone to ischial spine
What are the insertions of the levator ani muscles?
Some fibres insert into the perineal body as they encircle the urethra, vagina and the rectum. The rest of the fibres insert into the lower part of the coccyx
What are the perineal muscles?
Next layer after the levator ani
Transverse perineal muscles (superficial and deep), Bulbospongiosus, ischicavernosus
What is the urogenital diaphragm?
Tringular sheet of dense fibrous tissue that arises from the ischiopubic ramus which spans the anterior half of the pelvic floor. Attaches to the vagina, urethra and perineal body thereby supporting the pelvic floor
What is the perineal body and what is its function?
Occupies a central position (and role) on the pelvic
floor, between the vagina and rectum
Point of insertion of the levator ani muscles
Attached posteriorly to the external anal sphincter
(EAS) and the coccyx
Support of the perineal structures rely on it
What is the blood supply to the pelvic floor?
Pudendal arteries and veins
What is the lymphatic drainage of the pelvic floor?
Inguinal lymph nodes
What is the innervation of the pelvic floor?
(Branches of) pudendal nerve which originates from ventral rami of S2-S4
What is pelvic floor dysfunction?
refers to a wide range of symptoms and conditions that can arise as a result of problems to do with the pelvic floor.
Give examples of pelvic floor dysfunctions. (7)
o Pelvic organ prolapse, o Incontinence, o Posterior compartment pelvic floor dysfunction, o obstetric trauma (incl. episiotomy), o FGM, o Vaginismus, o Vulval pain syndromes.
WHat is pelvic organ prolapse?
Loss of support for the uterus, bladder or colon can result in a prolapse of any of these organs into the vagina.
What functional disturbances does POP cause?
Disturbance to anorectal, urinary and sexual function. It can also cause an altered sense of body image, leading to depressive symptoms.
What percentage of women experience POP to some degree?
40%
How are POPs classified?
By the compartment that the prolapse has occurred in, and the organ that has prolapsed.
What prolapases can occur in the anterior compartment? (3)
o Cystoceole = bladder
o Urethrocoele = urethra
o Cystourethrocoele = both
What prolpases can occur in the middle compartment?
Uterus = uterine prolapse
Vault prolapse
What is a vault prolapse?
After hysterectomy, apex of vagina may prolapse into vagina as the supportive ligaments have been cut
What is it called if the entire uterus prolapses into the vagina?
Procindentia
What prolpases can occur in the posterior compartment?
Rectocoele = rectum enterocoele = loops of bowel prolapse into rectouterine pouch
What are the risk factors for POP? (7)
Age, Parity, Vaginal delivery, Obesity and other causes of increased intra-abdominal pressure.
(Postmenopausal) oestrogen deficiency, Neurological or connective tissue disorders.
Give examples of neurological and connective tissue conditions that could cause POP.
Duchenne muscular dystrophy, Marfan’s, Ehlers Danlos
What may a patient complain of in POP?
Feeling a lump down below, dragging sensation or something ‘coming down’.
They may also experience symptoms relating to where the prolapse is occurring, e.g. constipation.
What needs to be considered when planning management for POP?
nature of symptoms and degree of bother
nature and extent of prolapse
completion of family and future pregnancy plans
sexual activity
fitness for surgery and anaesthesia
woman’s goals
work, physical activity and domestic circumstances
What non surgical interventions are available for POP?
Use of pessaries e.g. ring pessaries as additional support
Types include- ring, shelf and gelhorn pessaries
What surgical interventions are available for POP?
Many depending on type of prolapse. Anterior/posterior colporrhaphy (for anterior and posterior compartment prolapses), hysterectomy etc.
What is a risk factor for surgical intervention for POP?
Chance of recurrence and the potential for complications
What are Obstetric anal sphincter injuries (OASIs)?
Caused by perineal trauma during vaginal delivery. Also referred to as third- and fourth-degree perineal lacerations, these injuries involve the anal sphincter complex and, in more severe cases, anal mucosa
What can OASIS result in?
Weakness and damage to athe anal sphincter muscles leads to faecal incontinence
How can OASIS be prevented?
Thinking about episiotomy (risk groups and correct
angle) i.e. restrictive use
For every 6° the episiotomy is made away from the
midline, there is a 50% reduction in third-degree tear.
Perineal protection at crowning can be protective
Encouraging the mother NOT to push when the head is crowning
What is an episiotomy and why is it done?
Surgical incision of the perineum and the posterior vaginal wall, to aid delivery of a baby and/or prevent severe tears
What is the perineum?
The area between the anus and the scrotum or vulva.
What is stress continence?
Increased abdominal pressure causes ‘leaks’ of urine, as the support to the urethral sphincter (via the pelvic floor) is inadequate.-affected by dysfunction of the
pelvic floor
What is urge incontinence?
Overactive bladder- the loss of urine as soon as you feel the urge to go to the bathroom. - due to
problems with the bladder not the pelvic floor
What are the risk factors for stress in continence?
Same as POP, particularly age and oestrogen
deficiency.
What are managements for stress incontinence?
Pelvic floor exercises first line. Surgical treatment only if problems persist.
What is the surgical intervention for stress incontinence?
Colposuspension
Give 2 examples of vulval problems.
Vestibulodynia, Vaginismus
What is vestibulodynia?
Painful vulva
What is vaginismus?
Pain on vaginal penetration, due to involuntary muscle spasms (vagina very tight)
Define female genital mutilation.
Procedures involving partial or total removal of the external genitalia or other injury to the female genital organs, whether for cultural or other non-therapeutic reasons
What are the acute/chronic complications/consequences of FGM?
Acute - haemorrhage, shock, sepsis, infections and death
Late - Sexual dysfunction, fertility issues, chronic pain, menstrual disorders, urinary outflow obstruction
Psychological effects
What is posterior compartment pelvic floor dysfunction?
Range of conditions affecting the posterior part of the pelvic floor
What conditions are included in posterior compartment pelvic floor dysfunction?
Vaginal/rectal bulge, constipation/incomplete evacuation, anal incontinence, dyssynergic defecation etc.
What are causes of faecal incontinence in women?
Structural, e.g. Rectocele, rectal prolapse Drugs e.g.. Opiates, Iron supplements Dehydration Immobility Pregnancy Postoperative pain
what is Anal/faecal incontinence?
involuntary loss of flatus, liquid or solid stools that is a
social or hygienic problem.
Causes both physical and psychological distress - leads to significant impairment of quality of life
what is the most common cause of Anal/faecal incontinence?
obstetric anal sphincter injury.
