Test 3 muscles of perineum Flashcards
external anal sphincter insertion
passes around lateral aspects of anal canal, inserting into perineal body
external anal sphincter origin
kin and fascia surrounding anus and coccyx via annococcygeal ligament
external anal sphincter innervation
inferior anal nerve, branch of pudendal nerve S2-S4
external anal sphincter action
- constricts anal canal during peristalsis, resisting defication
- support and fixes perineal body /pelvic floor
bulbospongiosus MALE origin
MALE:
median raphe on ventral surface of bulb of penis and perineal body
bulbospongiosus MALE insertion
MALE:
surrounds lateral aspects of bulb penis and most proximal part of body of penis, inserting into perineal membrane, dorsal aspect of corpora spongiosum and cavernosa ,and fascia of bulb of penis
bulbospongiosus MALE innervation
Male:
muscular (deep) branch of perineal nerve, branch of pudendal nerve S2-S4
bulbospongiosus MALE action
MALE
- supports and fixes perineal body/pelvic floor
- compresses bulb of penis to expel last drops of urine/ semen
- assist erection by compressing outflow via deep perineal vein and by pushing blood from bulb into body of penis
bulbospongiosus FEMALE origin
Female:
perineal body
bulbospongiosus FEMALE insertion
FEMALE:
- passes on each side of lower vagina, enclosing bulband greater vestibular gland
- inserts oonto pubic arch and fascia of corpora cavernosa of clitoris
bulbospongiosus FEMALE innervation
Female:
muscular (deep) branch of perineal nerve, branch of pudendal nerve S2-S4
bulbospongiosus FEMALE action
Female:
- supports and fixes perineal body/pelvic floor
- sphincter of vagina
- assists in erection of clitoris (and bulb of vestibule)
- compresses greater vestibular gland
ischiocavernosus origin
internal surface of ischiopubic ramus and ischial tuberosity
ischiocavernosus insertion
embraces crus of penis or clitoris inserting onto inferiorand medial aspects of crus and perineal membrane medial to crus
ischiocavernosus innervation
muscular (deep) branch of perinealnerv,branch of prudendal nerve
ischiocavernosus action
maintains erection of penis or clitoris by compressing outflow veins and pushing blood from root of penis or clitoris into body
superficial transverse perineal origin
- internal surface of ischiopubic ramus and ischial tuberosity
- compressor urethra portion only
superficial transverse perineal insertion
passes along superior posterior border of perineal membrane to perineal body
superficial transverse perineal innervation
- muscula (deep) branch of perineal nerve, branch of pudendal nerve(S2-S4)
- dorsal nerve of penis or clitoris, terminal branch of pudendal nerve (S2-S4)
superficial transverse perineal action
support and fix perineal body (pelvic floor) to support abdominopelvic viscera nd resist intra-abdominal pressure
deep transverse perineal origin
- internal surface of ischiopubic ramus and ischial tuberosity
- compressor urethra portion only
deep transverse perineal insertion
- passes along superior posterior border of perineal membrane to perineal body
- and external anal sphincter
deep transverse perineal inervation
- muscula (deep) branch of perineal nerve, branch of pudendal nerve(S2-S4)
- dorsal nerve of penis or clitoris, terminal branch of pudendal nerve (S2-S4)
deep transverse perineal action
-support and fix perineal body (pelvic floor) to support abdominopelvic viscera nd resist intra-abdominal pressure
external urethral sphincter origin
- internal surface of ischiopubic ramus and ischial tuberosity
- compressor urethra portion only
external urethral sphincter insertion
-surrounds urethra superior to perineal membrane
MALE:also ascends to anterior aspect of prostate
FEMALE:some fibers also enclose vagina(urethrovaginal sphincter)
external urethral sphincter innervation
- muscula (deep) branch of perineal nerve, branch of pudendal nerve(S2-S4)
- dorsal nerve of penis or clitoris, terminal branch of pudendal nerve (S2-S4)
external urethral sphincter action
-compress urethra to maintain urinary continence
only
-FEMALE:urethrovginal sphincter portion alsocompresses vagina