pelvis Flashcards
Pelvis region
- area of transition between trunk and lower limbs
2. enclosed by bones, ligaments, muscles
sexual differences in pelves (4)
- xy- pelvic inlet xx- oval (not heart shaped)
- pelvic outlet; larger pelvic outlet; everted ischial spines
- pelvic cavity; shallower greater & lesser pelves
- pubic arch; rounded & wider subpubic angle
pelvic cavity
- funnel shaped space bound by bones of the pelvis
- greater pelvis: btw ala of ilium & p. inlet
- lesser p: btw p. inlet & p. outlet
- continuous with abdominal cavity
- contains urinary bladder, terminal parts of ureters, pelvic genital organs, rectum
perineum
two parts
male/XX
- triangular area of trunk btw thighs and buttocks extending from pubis to coccyx
- seen best in lithotomy position-diamond shape
- separated from pelvic cavity by the pelvic diaphragm (pelvic floor)
- 2 parts: urogenital triangle, anal triangle
- males: penis, scrotum, anus
- females: vulva, clitoris, vagina, anus
OIAN Obturator internus
O: ilium, superior pubic ramus & ischium (anterolateral wall of oelvis minor)
I: greater trochanter of femur
A: none
N: nerve to obturator internus
Piriformis OIAN
O: 2-4th sacral segments
I: greater trochanter of femur
A: none
N: S1-2
Muscles making up pelvic diaphragm function of pelvic diaphragm
- levator ani muscle + coccygeus muscle
- form floor of pelvis, suporting abdominopelvic organs
- aids in urinary and fecal continence
- raises pelvic floor during urination, vomiting, coughing, weight lift
- during parturition, supports the fetal head while the cervix dilates for delivering the baby
Three names that make up the levator ani
- puborectalis
- pubococcygeus
- Iliococcygeus
Tendinous arch of levator ani
- thickened fascia of obturator internus muscle
- attachment for levator ani muscle
Iliococcygeus (one of three muscle making up the levator ani OIAN
O-tendinous arch of obturator fascia
I-perineal body, coccyx
A-support pelvic viscera
N-S4, inferior rectal nerve, cocygeal plexus
OIAN of puborectalis (levator ani)
O-inferior ramus of pubis
I-rectum, prostate in males, vagina in female
A-support pelvic viscera
N-S4-5
OIAN of pubococcygeus
O-inferior ramus of pubis tendinous arch of obturator internus
I-coccyx
A-support pelvic viscera
N-S4-5
involve in episiotomy. Injury may lead to stress incontinence.
OIAN coccygeus
O-ischial spine
I-inferior end of sacrum, coccyx
A-supports pelvic viscera and flexes coccyx
N-S4-5
Pudendal nerve
-supplies sensory innervation to perineum
walls of pelvic cavity posterior- anterior- lateral- inferior- superior-
posterior-sacrum, piriformis m. anterior- pubic rami, pubic symphysis lateral- obturator internus inferior- levator ani m. (iliococcygeus, pubococcygeus, puborectalis) superior-open to abdominal cavity