Anatomy of the Pelvis Flashcards
What is meant by the lesser (true) pelvis?
The aspect of the pelvic where the pelvic organs lie (below the pelvic brim), above here you still have abdominal viscera.
What type of joint is the symphysis pubis?
Secondary cartilaginous joint, as it unites articulating surfaces by using a fibrocartilaginous disc
Name the three main ligaments of the pelvis
Sacrotuberus (sacrum to tubercle), sacrospinous (sacrum to the ischial spine) and sacroiliac (sacrum to ilium)
Describe the role of the sacrotuberous and sacrospinous ligaments
Prevent the lower end of the sacrum from being rotated upward at the sacroiliac joint as well as converting the sciatic notch into the greater and lesser sciatic foramina
How does the pelvic cavity differ between males and females?
More cylindrical in males, more cone shaped in men.
What makes up the anterior pelvic wall?
Pubic rami and pubic sympyhsis
What makes up the posterior pelvic wall?
Sacrum, coccyx and piriformis
What makes up the lateral pelvic wall?
Hip bone (below pelvic inlet), obturator membrane, sacrospinous and sacrotuberous ligaments as well as the obturator internus muscle
What is the pelvic diaphragm?
The pelvic floor
What is above and below the pelvic diaphragm?
Above = true pelvis Below = perineum
What makes up the pelvic diaphragm?
Levator ani muscle and coccygeus
Why is the pelvic diaphragm incomplete anteriorly in females?
The urethra and vagina are here in females
Describe the role of the levator ani muscle
It supports and maintains pelvic viscera position, resists pressure (intrapelvic and expulsive from abdomen), assists urethral sphincter and has important action at ano-rectal junction and vaginal sphincters also.
Name the 4 divisions of the levator ani muscle
- Levator prostate/sphincter vaginae (unimportant)
- Puborectalis
- Pubococcygeus
- Iliococcygeus
What is the function of the levator prostate/sphincter vaginae ?
To form a sling around prostate/vagina and inset into perineal body to support prostate or constrict vagina
