SIJ Anatomy Flashcards
SIJ pain contributes to dx of non-specific LBP in ____% of individuals
15-30%
T/F: isolated SIJ probs are rare
T
male vs female pelvis
female - wider, flatter, larger outlet
male - more vertical, smaller outlet
the sacrum is ____ on the anterior side and _____ on the posterior side
anterior - concave
posterior - convex
which mm originates on the anterior side of the sacrum?
piriformis
how are sacral facet joint oriented?
inverted L
age related changes to sacrum
articular surfaces become smoother –> higher risk of slip
____ of each innominate articulates with the sacrum = SIJ
ilium
which ligs are pain generators of the SIJ?
anterior and posterior SI ligs
which motions does the anterior SIJ ligs limit?
all motions
what is the most important lig of the SIJ?
interosseous SI ligs
which motions does the interosseous SIJ ligs limit?
anterior and inferior movements of sacrum
which lig is point tender indicates SIJ dysfunction?
interosseous
which motions does the posterior SIJ ligs limit?
anterior iliac rotation (sacral counternutation)
which motions does the sacrotuberous ligs limit?
posterior iliac rotation (nutation)
which motions does the sacrospinous ligs limit?
posterior iliac rotation (nutation)
which structure is a common source of groin pain especially in athletes?
pubic symphysis
purpose of the sacrum
keystone to transmit forces –> must be very stable
which mm make up the levator ani?
pubococcygeus
pubrorectalis
iliococcygeus
how many muscles attach to the SIJ?
35
what muscles are the only 2 that can directly produce SIJ motion?
piriformis
pubococcygeal
which structures compose the posterior oblique system?
lats
contra glute max
TL fascia
which structures compose the anterior oblique system?
EO
IO
contra hip add
anterior abdominal fascia
pain during _____ can indicate SIJ dysfunction
SLS
which structures compose the lateral mm system?
glute med
glut min
contra add
which structures compose the inner mm system?
multifidi
TA
pelvic floor
diaphragm
which mm system stabilizes the SIJ?
inner
which ligs limit sacral nutation?
sacrotuberous
sacrospinous
interosseous
which ligs limit sacral counternutation?
anterior & posterior SI ligs
which motion decreases pelvic outlet size?
sacral counternutation
a posterior innominate indicates sacral ____
nutation
an anterior innominate indicates sacral ____
counternutation
which motions cause decreased L lordosis?
nutation and posterior innominate
sacral base is ____ and apex is ____ (A/P?)
base - anterior
apex - posterior
