Sacral Mechanics and Motion

Question 1

What restricts posterior motion?

Answer 1

sacroiliac ligaments

Question 2

What restricts anterior motion?

Answer 2

sacrotuberous/sacrospinus ligaments

Question 3

Shaped of the sacroiliac joint?

Answer 3

C or L shaped

Question 4

S1-4 and S5 have parasympathetic innervation from what? Sympathetic?

Answer 4

pelvic splanchnic nerves

sacral splanchnic nerves

Question 5

Lumbar flexion = sacral _____
Lumbar extension = sacral ______
Lumbar rotation left = sacral rotation _____

Answer 5

extension
flexion
right

Question 6

Shifting weight to one leg causes an ______ oblique axis.

Answer 6

ipsilateral

right leg = right oblique axis

Question 7

Standing flexion test, seated flexion test, and ASIS compression test apply to what?

Answer 7

the sacroiliac joint

Question 8

What does the backward bending test tell you?

Answer 8

determines if one side of the sacral base is posterior and resists the anterior motion induced by backward bending

Question 9

Early stance phase: At heel strike the hamstrings tighten and pull the ____ innominate posterior.

Answer 9

ipsilateral

Question 10

Late stance phase: As the quadriceps tighten at toe off, the pull the _____ innominate anterior.

Answer 10

ipsilateral

Question 11

As the body’s center of gravity shifts towards the supporting leg, the lumbar spine sidebends _____ and rotates ___ from the weight bearing leg.

Answer 11

towards, away

Question 12

Initiated at right heel strike and continuing into early stance phase: the right innominate rotates _____, the upper pole of the right SI joint ______, the sacrum rotates _____ around a _____ oblique axis.

Answer 12

posteriorly, tightens, right, right

L5 is N SR RL - the sacrum and L5 are rotated in opposite directions