lecture 4a: anatomy and biomechanics review of SI joint

Question 1

what complex is the primary stabilizer for static and dynamic task

Answer 1

lumbo pelvic hip complex

Question 2

t/f: isolated problems in this area are RARE

Answer 2

true

Question 3

what joint is the intersection between spine and lower extremities

Answer 3

SI joint

Question 4

what contributes to dx of ‘non-specific LBP’
in 15-30% of individuals

Answer 4

SI joint pain

Question 5

what kind of joint is the sacrum

Answer 5

facet joint

Question 6

what is the articulation of the base , apex and ala of the sacrum

Answer 6

base- w 5th lumbar vertebra
apex- w coccyx
ala- ilium

Question 7

what is the origin of the piriformis

Answer 7

anterior aspect of s2. s3. s4

Question 8

what side of the sacrum is concave and convex

Answer 8

anterior side is concave
posterior side is convex

Question 9

the sacrum is __- fused sacral vertebra

Answer 9

5

Question 10

what forms the median sacral crest

Answer 10

4 fused spinous tubercles

Question 11

the posterior side of the sacrum is attachments for what mm’s

Answer 11

ES
multifidi
glute max
T-L fascia

Question 12

what forms the innominates of the pelvic

Answer 12

ilium , ishchium and pubic bone fuse at
acetabulum to form each innominate

Question 13

___ of each innominate articulates w/
the sacrum = SI joint

Answer 13

Ilium

Question 14

___ ___ of each innominate
articulates w/ the other at pubic
symphysis

Answer 14

pubic bone

Question 15

what motions does the anterior SI ligaments limit

Answer 15

all motions

Question 16

what SI ligaments are part of SI joint pathology: pain generators

Answer 16

anterior SI ligaments
posterior SI joint ligaments

Question 17

what is the most important ligaments of SIJ

Answer 17

interosseous SI ligaments

Question 18

what motion does the Interosseous SI ligament limit

Answer 18

anterior and inferior movements of sacrum

Question 19

what motion does the posterior SI joint ligament limit

Answer 19

limit ant iliac rotation (or sacral counternutation)

Question 20

what 2 ligament of the SIJ limit posteior iliac rotation (or sacral nutation)

Answer 20

sacrotuberous ligament
sacrospinous ligament

Question 21

what is a common source of groin pain …. particularly in athletes

Answer 21

pubic symphysis

Question 22

what are the pelvic floor mms

Answer 22

• Levator ani mm.
• Pubococcygeus
• Puborectalis
• Iliococcygeus
• Coccygeus m

Question 23

what does the pelvic floor mm assist in

Answer 23

lumbopelvic stability

Question 24

what are the Only 2 muscles can directly
produce SI joint motion

Answer 24

• Piriformis
• Pubococcygeal

Question 25

what is the primary function of the piriformis

Answer 25

-• Hip ER and abd
• When hip flex >90°, piriformis
becomes hip IR

Question 26

what is included in the posterior oblique system

Answer 26

Lats, contralateral glute max, T-L
fascia

Question 27

what is included in the anterior oblique system

Answer 27

• EO and IO, contralateral hip add
  and ant abdominal fascia

Question 28

what is included in the lateral mm system

Answer 28

• Glute medius and minimus,
  contralateral hip add

Question 29

what is included in the inner mm system

Answer 29

• Multifidi, TA, pelvic floor and
  diaphragm

Question 30

what does the inner mm system stabilize

Answer 30

SI joint

Question 31

what is the nerve supply for the anterior and posteior portion of the the SI joint

Answer 31

anterior : posterior rami L2-S3

posterior: posterior rami L3-S3

Question 32

how does the base and the apex move for sacral nutation (flexion)

Answer 32

• Base moves anterior and inferior
• Apex moves posterior and superior

Question 33

what is sacral nutation (flexion) motion limited by

Answer 33

SI, sacrotuberous & sacrospinous ligaments

Question 34

during sacral nutation( flexion) how does the innominates move and it ___ lumbar lordosis and ___ hip flexion

Answer 34

posteriorly (posterior pelvic tilt)

decrease

increase

Question 35

how does the base and the apex move during sacral counternutation (extension)

Answer 35

• Base moves superior and posterior
• Apex moves inferior and anterior

Question 36

what is sacral counternutation(extension) motion limited by

Answer 36

SI ligaments

Question 37

how do the innominates move during sacral counternutation (extension) and this lead to ____ lordosis

Answer 37

anterior innominates which leads to increased lordosis

Question 38

posteior innominate leads to sacrum ____

Answer 38

nutation (sacrum flexed)

Question 39

____ ` innominate 🡪 sacrum
counternutation

Answer 39

Anterior (sacrum extended)