Quiz 3: Lecture 9 Pelvis Flashcards
What is the pelvic inlet?
Superior portion of opening in the pelvis
What is the pelvic outlet?
The inferior portion of opening in the pelvis
What structures are in the pelvic cavity?
Urinary bladder, ureters, pelvic genital organs, rectum, blood vessels, lymphatics, sacral nerves
The hip bone (also known as the innominate bone or Os Coxae) is comprised of 3 bones, what are they? Where do they meet?
- Ischium
- ilium
- pubis
They all meet at the acetabulum
Structures of the pelvic inlet (anterior/inferior to posterior/superior)
- pubic symphysis (joint)
- pubic bone
- medial part of ilium
- Ala of sacrum
Structures of the pelvic outlet (anterior/inferior to posterior/superior)
- inferior pubic bone/symphysis
- ischial tuberosity
- sacrotuberous ligament
- coccyx
What is the ligament that runs from ASIS to pubic bone?
Inguinal ligament
What are the openings between the ischium and pubic bone called?
Obturator foramen (2)
What membrane fills the obturator foramen
Obturator membrane
Which ligament runs from the sacrum to ischial tuberosity?
Sacrotuberous ligament
Differentiate between a female and male pelvis
Female:
- inlet is more circular
- ischial spines projects not as far medially
- angle between ischial tuberosity is wide
Male:
- inlet is more heart shaped
- ischial spines project further in medially
- angle between ischial tuberosity is more narrow
What is the pubic symphysis?
Cartilage fills the gap between right and left pelvic bones (held together by the superior and inferior pubic ligaments)
What type of joint is the pubic symphysis?
Fibrocartilaginous
T or F? Motion increases dramatically at the pubic symphysis during child birth
True
What makes up the anterior pelvic wall?
Pubic bones and pubic symphysis
What is the most lateral muscle of the pelvis wall?
obturator internus
What makes up the posterior pelvic wall?
- Sacrum and coccyx
- adjacent parts of the ilia
- SI joints
- piriformis
What is the pelvic floor (aka pelvic diaphragm)
Muscles that stretch from the coccyx bone to the pubic symphysis
- levator ani (puborectalis, pubococcygeus, iliococcygeus)
- coccygeus muscle
What is the origin and insertion of the coccygeus muscle?
Origin: Ischial spine
Insertion: sacrum/coccyx
Which nerve innervates the levator ani?
Inferior rectal branch of pudendal nerve
What does the coccygeus muscle support?
Pelvic viscera
The ________ nerve is the somatic (motor/sensory) nerve to the pelvis
Pudendal
Which sphincter can you voluntarily control?
External sphincter (when you are waiting to go to the bathroom)
Where does the pudendal nerve go?
Passes out of the greater sciatic foramen, then back into lesser sciatic foramen to innervates levator ani and perineal muscles