S10) Pelvic Cavity and Pelvic Floor Flashcards
Identify the 5 functions of the pelvic floor
- Supports the pelvic organs (vagina, uterus, ovaries, bladder, rectum)
- Maintains intra-abdominal pressure (coughing, vomiting, sneezing, laughing)
- Facilitates defaecation and micturition
- Maintains urinary and faecal continence
- Facilitate childbirth
What are the three types of support provided by the pelvic floor?
- Suspension
- Attachment
- Fusion
Describe which ligaments allow the pelvic floor to support pelvic organs through suspension
Suspension is vertical support (against gravity) wherein:
- The cardinal ligaments hold the cervix and upper vagina in place
- The uterosacral ligaments hold the back of the cervix and upper vagina laterally
- Round ligament maintains the anteverted position of the uterus
The diaphragm provides support through fusion by involving the urogenital diaphragm and the perineal body.
Describe this
The lower half of the vagina is supported by fusion of the vaginal endopelvic fascia to the perineal body (posteriorly), the levator ani (laterally) and the urethra (anteriorly)
What composes the pelvic floor?
- Levator ani muscles
- Urogenital diaphragm/perineal membrane
- Perineal body
- Perineal muscles
The pelvic floor is composed predominantly of the levator ani muscles.
Describe their structure and anatomical location
- Form a broad U-shaped sheet which stretches posteromedially from either side of the pelvis to meet in the middle line
- They encircle the urethra, vagina, rectum and reaching the coccyx
Which muscles compose the levator ani muscles?
- Pubococcygeus
- Puborectalis
- Iliococcygeus
Describe the origin and attachment of the levator ani muscles
- Origin: posterior pubic rami, obturator internus, medial aspect of ischial spine
- Attachment: insert as they encircle the urethra / vagina / rectum/ lower part of the coccyx
What is the urogenital diaphragm?
The urogenital diaphragm is a triangular sheet of dense fibrous tissue
The urogenital diaphragm supports the pelvic floor.
In three steps, describe its anatomical course
⇒ Spans the anterior half of the pelvic outlet
⇒ Arises from the inferior ischiopubic ramus
⇒ Attaches medially to the urethra, vagina, perineal body
The perineal body provides a point of insertion of the levator ani muscles.
Describe its anatomical location
- Occupies a central position on the pelvic floor, between the vagina and rectum
- Attaches posteriorly to the external anal sphincter and the coccyx
What is pelvic floor dysfunction?
Pelvic floor dysfunction refers to a wide range of issues that occur when muscles of the pelvic floor are weak, tight / there is an impairment of the sacroiliac joint, lower back, coccyx, or hip joints
Identify 4 causes of pelvic floor dysfunction
- Drugs eg. opiates
- Dehydration
- Immobility
- Pregnancy
Identify some risk factors of pelvic floor dysfunction
- Pelvic organ prolapse
- Urinary incontinence
- Obstetric trauma (episiotomy)
- FGM
What is pelvic organ prolapse?
POP refers to the loss of support for the uterus, bladder, colon or rectum, leading to prolapse of one or more of these organs into the vagina
What are the different types of FGM?
In a PR examination, which two muscles would you feel contracting when the patient squeezes on the examining finger?
- Puborectalis muscle
- External anal sphincter
What is an episiotomy?
An episiotomy is a surgical incision of the perineum and the posterior vaginal wall made just before delivery to enlarge the vaginal opening
Which tissue structures require repair after an episiotomy?
- Vagina
- Mucosa
- Muscles
- Skin
