Pelvic Floor and Perineum Flashcards
What are the muscles in levator Ani
Puborectalis
Pubococcygeus
Iliococcygeus
Puborectalis IO innervation
Origin:
* Posterior surface of the bodies of pubic bones
Insertion:
* Fibers travel posterior to rectum where they combine with the fibers of the opposite 1/2 of the puborectalis (forms a “sling” posterior to rectum)
Nerve to levator ani muscles
Puborectalis Action
- Draws distal rectum upwards and forwards
- Aids in contraction of anal sphincter
- Plays a major role in maintaining fecal continence
Pubococcygeus IO innervation action
Origin:
* Posterior surface of the bodies of pubic bones (lateral to puborectalis)
Insertion:
* Coccyx
* Anococcygeal ligament
* Perineal body and musculature of prostate (males)/vagina (females)
Innervation
* Nerve to levator ani muscles
* Inferior rectal nerves
Action
* Elevation of pelvic floor
Iliococcygeus IO Innervation
Origin:
* Ischial spine
* Fascia of obturator internus muscle
Insertion:
* Anococcygeal ligament
* Coccyx
- Nerve to levator ani muscles
- Inferior rectal nerves
Iliococcygeus action
- Elevation of pelvic floor
- Support for pelvic viscera
- Comprises part of pelvic diaphragm
Coccygeus IO innervation action
Origin:
* Ischial spine
* Sacrospinous ligament
Insertion:
* Inferior end of sacrum
* Coccyx
Innervation
Nerve to levator ani muscles
Action
* Support for pelvic viscera
* Elevation of pelvic floor
External anal sphincter IO innervation action
Origin:
* Perineal body
Insertion:
* Anococcygeal body
Innervation
* Inferior rectal nerve
* Perineal nerve
Action
* Constriction of anal canal to prevent defecation
* Relaxes from a tonic state of contraction to allow defecation
Superficial transverse perinei IO Innervation Action
Origin:
* Medial surface of ischial ramus
Insertion:
* Contralateral muscle and the perineal body
Action
* Fixation and stabilization of perineal body
Innervation
* Perineal nerve
Deep transverse perinei
Origin:
* Inferior ischial ramus
Insertion:
* Tendinous raphe of the contralateral deep perineal muscle
Action
* Fixation and stabilization of the pelvic floor
* Expulsion of semen (males)
* Expulsion of urine (males and females)
Innervation
* Perineal nerve
Ischiocavernosus
Origin:
* Medial surface of ischial tuberosity
* Ischiopubic ramus
Insertion:
* Corpus cavernosum
* Crus of the clitoris (females)
* Crus of the penis (males)
Action
* Compression of the corpus cavernosum
Innervation
* Perineal nerve
Bulbospongiosus
Origin:
* Females: Perineal body and fascia of the bulb of vestibule
* Males: Central tendinous point and the midline raphe on the bulb of the penis
Insertion:
* Perineal membrane
* Females: Corpus cavernosum of the clitoris
* Males: Dorsal surface of the corpus spongiosum and the deep penile fascia
Action
* Females: Compression of vestibular bulb and constriction of vaginal orifice
* Males: Compression of bulb of penis and compression of spongy urethra
Innervation
* Perineal nerve
