Flashcards in Pelvic Floor Deck (28)
Where are the pelvic viscera located?
Pelvic cavity (true pelvis)
Located within the lesser part of the pelvis, beneath the pelvic brim.
what makes put he lateral wall of the pelvic cavity?
Obturator internus and piriformis.
What is the pelvic floor?
Funnel shaped musculature structure that attaches to the lesser pelvis, separating the pelvic cavity from the inferior perineum.
What are the gaps in the pelvic floor and what do the transmit?
Urogenital hiatus - urethra (anterior)
Rectal hiatus - anal canal (central)
What is the pelvic floor formed by?
- Coccygeus and levator ani muscles
- Fascia covering the superior and inferior aspect of these.
Superficial muscles and structures
- Urogential perinuem
- Anal perineum
What are the functions of the pelvic floor?
Support the abdominal viscera through tonic contraction.
Resist increases in intra-abdominal pressure (coughing, heavy lifting) with sphincter action on rectum and vagina.
Urinary and fecal continence
- Muscle fibres have a sphincter action on rectum and urethra - relax to allow defection.
What are the boundaries of the perineum
Ant: pubic symphsis
Lateral: inferior pubic rami, ischial rami, ischial tuberosity, sacrotuberous ligaments
Roof: Pelvic floor
Base: Skin and fascia
What divides the perineum into the urogenital and anal perineum?
Imaginary line between ischial tuberosities
What is found in the urogenital perineum?
Sphincter urethrae muscles
Superficial fascia (perineal membrane)
What are the superficial perineal muscles?
Bulbospongiosus - compresses urethra and vagina
Ischiocavernosus - compresses corpus cavernosum
Superficial transverse perineal muscle - stabilises perineal body
What is found in the anal perineum?
Anus (anal orifice)
What are the levator ahi muscles and what innervates them?
Pudendal nerve (S2,S3,S4)
Extends from pubic bone body around anal canal in U shape
Maintains faecal continence
Relaxes during defecation
Pubic bone body and tendinous arch.
Around urogenital hiatus to cocyx via anococcygeal liigament
Elevates pelvic floor
Ischial spines and posterior tendinous arch to coccyx via anococcygeal ligament
Elevates pelvic floor
What is coccygeus? Innervation?
Smaller, most posterior pelvic floor component.
Coccygeus lies to the posterior, overlying the sacrospinous ligament.
Anterior rami of S4 and S5
Elevates pelvic floor
What is the perineal body? What does it consist of?
Fibromsucular mass at junction between urogenital and anal triangles in the perineum.
Consists of skeletal muscle, smooth muscle, collagenous and elastic fibres.
What is the function of the perineal body in women?
Anchoring perineal muscles and rectum
Supports the lower posterior part of the vaginal wall against prolapse and forms a dense attachment for the two halves of the levator muscles in the midline.
Acts as a tear-resistant body between the vagina and external anal sphincter muscle tube during childbirth (now stressed by evolution of large fetal head size).
What attaches to the perineal body?
• External anal sphincter
• External urethral sphincter
• Superficial and deep transverse perineal muscles
• Fibres of levator ani
What happens if the perineal body ruptures in childbirth?
Prolapse of structures such as vagina and uterus.
Describe the damage childbirth can cause to the pelvic floor muscles
Fibres of pubococcygeus can be damaged during childbirth --> Prolapse or herniation of the bladder/urethra with incontinence.
Medial fibres of puborectalis (insert into perineal body) torn
Herniation of rectum
--> Faecal incontinence.
What may pelvic floor damage lead to?
Stretch of the pudendal nerve
- Neuropraxia and muscle weakness
Stretch and damage of pelvic floor and perineal muscles
Stretch/rupture of ligament supports of muscles
- Ineffective muscle action
Prolapse of organs
- Loss of tone in muscles/ damage to perineal body
What is the function of legator ahi in childbirth? Which muscles are most prone to injury? Why?
Supporting fetal head
Pubococcygeus and puborectalis as they are most medial.
Why does prolapse of pelvic organs occur?
Damage to perineal body
Loss of tone in pelvic muscles
Give risk factors for pelvic floor dysfunction
Number of vaginal deliveries
Menopause (atrophy of tissueS)
Family history of pelvic floor dysfunction
Intrinsic CT laxity
What are the treatments for pelvic floor dysfunction?
Pelvic floor muscle exercises
- safe, effective
- Increase support to sphincter mechanisms and prevent descent of bladder neck
- Tenison free vaginal tape
Restore CT support
What are the side effects of continence sugeries?
Voiding difficulty, urinary retention
Overactive bladder disease