Skeletn of the Lower Extremities Flashcards
The lower extremities consist of what?
The girdle and the limb
What are the functions of the lower extremity?
-transmits the bodys weight to the ground keeping balance, allows for locomotion
What does the pelvic girdle consist of?
two coxal (hip) bones
How do the two coxal bones unite?
anteriorly at the pubic symphysis, and posteriorly with the sacrum at the SI joint
What is the bony pelvis?
the complete ring composed by the coxal bones, the public symphysis, the sacrum and the coccyx
What are the functions of the bony pelvis?
provides strong support for VC + pelvic organs, connects lower limb to axial skeleton
In a new born the coxal bones are united by what?
hyaline cartilage
When does the bones of the coxal bone fuse? Where?
by the age of 23 at acetabulum
What are the bones of the coxal bones?
ilium (superior), pubis (inferior and anterior), ischium (inferior and posterior)
What is the largest portion of the coxal bone?
ilium
What is the ilium composed by?
ala (superior), body (inferior)
True or false: the body of the ilium is not part of the acetabulum
False: the body IS part of the acetabulum
What is the ischium composed by?
body (superior), ramus (inferior)
What two bones fuse to form the obturator foramen?
pubis and ischium
What is the pubis composed by?
superior ramus, inferior ramus and body
What unites the two pubes?
pubic symphysis
What are the portions of the bony pelvis?
False (greater) pelvis (superior), True (lesser) pelvis (inferior)
What forms the pelvic brim? (order beginning posteriorly)
1.sacral promontory 2. arcuate line 3.pectineal line 4.pubic crest 5.public symphysis
What is the pelvic inlet?
the superior opening of the true pelvis bordered by the pelvic rim
What is the pelvic outlet?
the inferior opening of the true pelvis covered by muscles of the pelvic floor
What is the pelvic axis?
determined by the center points of both pelvic inlet and outlet, the route of the babys head as it descends through the pelvis
What is the difference between the general structure between the female and male pelvis?
Female: light and thin, Male:heavy and thick
What is the difference between the false pelvis between the female and male pelvis?
F: shallow, M:deep
What is the difference between the pelvic brim (inlet) between the female and male pelvis?
F: wide and more oval, M: narrow and heart shaped
What is the difference between the pubic arch between the female and male pelvis?
F: Greater than 90 degree, M: Less than 90 degree
What is the difference between the coccyx between the female and male pelvis?
F: more moveable and straight down, M:less moveable and angled anteriorly
What is the difference between the sacrum between the female and male pelvis?
F: shorter and wider, M: longer and narrower
What is the difference between the pelvic outlet between the female and male pelvis?
F: wider, M: narrower
What is the SI joint formed by?
auicular surface of the sacrum and ilium
True or False: the SI joint is not a significant load bearing joint
False: the SI joint IS a significant load bearing joint