SIJ Anatomy

Question 1

SIJ pain contributes to dx of non-specific LBP in ____% of individuals

Answer 1

15-30%

Question 2

T/F: isolated SIJ probs are rare

Answer 2

T

Question 3

male vs female pelvis

Answer 3

female - wider, flatter, larger outlet
male - more vertical, smaller outlet

Question 4

the sacrum is ____ on the anterior side and _____ on the posterior side

Answer 4

anterior - concave
posterior - convex

Question 5

which mm originates on the anterior side of the sacrum?

Answer 5

piriformis

Question 6

how are sacral facet joint oriented?

Answer 6

inverted L

Question 7

age related changes to sacrum

Answer 7

articular surfaces become smoother –> higher risk of slip

Question 8

____ of each innominate articulates with the sacrum = SIJ

Answer 8

ilium

Question 9

which ligs are pain generators of the SIJ?

Answer 9

anterior and posterior SI ligs

Question 10

which motions does the anterior SIJ ligs limit?

Answer 10

all motions

Question 11

what is the most important lig of the SIJ?

Answer 11

interosseous SI ligs

Question 12

which motions does the interosseous SIJ ligs limit?

Answer 12

anterior and inferior movements of sacrum

Question 13

which lig is point tender indicates SIJ dysfunction?

Answer 13

interosseous

Question 14

which motions does the posterior SIJ ligs limit?

Answer 14

anterior iliac rotation (sacral counternutation)

Question 15

which motions does the sacrotuberous ligs limit?

Answer 15

posterior iliac rotation (nutation)

Question 16

which motions does the sacrospinous ligs limit?

Answer 16

posterior iliac rotation (nutation)

Question 17

which structure is a common source of groin pain especially in athletes?

Answer 17

pubic symphysis

Question 18

purpose of the sacrum

Answer 18

keystone to transmit forces –> must be very stable

Question 19

which mm make up the levator ani?

Answer 19

pubococcygeus
pubrorectalis
iliococcygeus

Question 20

how many muscles attach to the SIJ?

Answer 20

35

Question 21

what muscles are the only 2 that can directly produce SIJ motion?

Answer 21

piriformis
pubococcygeal

Question 22

which structures compose the posterior oblique system?

Answer 22

lats
contra glute max
TL fascia

Question 23

which structures compose the anterior oblique system?

Answer 23

EO
IO
contra hip add
anterior abdominal fascia

Question 24

pain during _____ can indicate SIJ dysfunction

Answer 24

SLS

Question 25

which structures compose the lateral mm system?

Answer 25

glute med glut min contra add

Question 26

which structures compose the inner mm system?

Answer 26

multifidi TA pelvic floor diaphragm

Question 27

which mm system stabilizes the SIJ?

Answer 27

inner

Question 28

which ligs limit sacral nutation?

Answer 28

sacrotuberous sacrospinous interosseous

Question 29

which ligs limit sacral counternutation?

Answer 29

anterior & posterior SI ligs

Question 30

which motion decreases pelvic outlet size?

Answer 30

sacral counternutation

Question 31

a posterior innominate indicates sacral ____

Answer 31

nutation

Question 32

an anterior innominate indicates sacral ____

Answer 32

counternutation

Question 33

which motions cause decreased L lordosis?

Answer 33

nutation and posterior innominate

Question 34

sacral base is ____ and apex is ____ (A/P?)

Answer 34

base - anterior apex - posterior