the pelvic floor Flashcards
pelvic floor structure
formed by levator ani and coccygeus
pelvic floor structure
attaches to walls of lesser pelvis, separating the pelvic cavity from perineum inferiorly
has urogenital and rectal hiatus
urogenital hiatus
anteriorly situated gap, which allows passage of urethra and vagina
rectal hiatus
centrally positioned gap, allows passage of anal canal
functions of pelvic floor
support of abdominopelvic viscera
resistance to increase in intra-pelvic/ abdominal pressure during activities such as coughing or lifting heavy object
urinary and faecal continence
muscles of pelvic floor
levator ani
coccygeus
fascia covering
levator ani muscles
composed of 3 separate muscles
- pubococcygeus
- puborectalis
- iliococcygeus
attachments of levator ani muscles
anterior: pubic bodies of pelvis bones
laterally: thickened fascia of obturator interns muscle (tendinous arch)
posteriorly: ischial spines of pelvic bones
innervation of levator ani muscles
anterior ramus of S4 and branches of pudendal nerve
puborectalis
U-shaped sling
extends from bodies of pubic bones, past urogenital hiatus and around anal canal
tonic contraction bends canal anteriorly, creating anorectal angle at anorectal junction
maintains faecal continence
pubococcygeus
main constituent of levator ani
arise from body of pubic bone and anterior aspect of tendinous arch
Fibres travel round margin or urogenital hiatus and run posteromedially.
Attach at coccyx and anococcygeal ligament
iliococcygeus
thin muscle fibres
start anteriorly at ischial spines and posterior aspect of tendinous arch
attach posteriorly to coccyx and anococcygeal ligament
Action: elevtes pelvic floor and anorectal canal
coccygeus innervation
innervated by anterior rami of S4 and S5
coccygeus
originates from ischial spines and travel to lateral aspect of the sacrum and coccyx, along Sacrospinous ligament
