Exam 2 Lumbopelvic Flashcards Preview

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Flashcards in Exam 2 Lumbopelvic Deck (50):
1

What is the most important characteristic of the lumbar spine?

it must bear tremendous loads created by body weight, lifting, and muscle actions

2

In addition to bearing heavy loads, what other responsibility does the lumbar spine have that places significant biomechanical demand on this region?

trunk mobility

3

T/F: the inferior articular processes of the L/S are concave and face anterolaterally.

False; convex

4

Describe the superior articular processes of the L/S.

concave and face posteromedially

5

What plane do the lumbar facets lie in primarily?

the sagittal plane

6

What motion is limited in the L/S? increased?

rotation;
flexion/extension

7

Which facets of the L/S have a coronal orientation rather than sagittal? What motion does this limit?

L5/S1 facets;
limits posterior/anterior shear (Z translation)

8

T/F: the lumbar facets normally carry 18% of the axial load and up to 33% in extension.

True

9

Which region of the L/S has the greatest combined flexion/extension? Least?

L5-S1;
L1-L2

10

Which region of the L/S has the greatest range of lateral bending (ThetaZ)? Least?

L3-L4;
L5-S1

11

Which region of the L/S has the greatest one side axial rotation (Theta Y)? Least?

L1-L5 all have relatively equal axial rotation;
L5-S1 has the least axial rotation

12

What motions are coupled in the L/S? What does this mean for spinous?

lateral bending is coupled with axial rotation;
spinous to ipsilateral side

13

Is the nucleus of the IVD in the L/S more anterior, posterior, or in the middle?

posterio

14

What is the disc height-to-body height ratio in the L/S?

1:3; greatest resistance to axial compressive forces

15

What is the name for the enlargement of the spinal cord that is protected by the L/S? What other main structure is protected by the L/S distal to the lumbar enlargement of the spinal cord?

conus medullaris;
cauda equina

16

What bone is the CNS tethered to via the filum terminale?

coccyx

17

Where does the spinal cord end? What do the nerve roots continue down the spinal canal as?

L2:
cauda equina

18

T/F: Nerve roots exit the dura of lumbar spinal canal slightly below the foraminal openings to provide "slack" which prevents stretching of the nerve roots.

False; NRs exit the dura slightly above the foraminal openin, causing therir course to be more oblique and their length to increase

19

T/F: The Lordotic curve of the L/S is considered a primary curve.

False; secondary curve

20

Where is the apex of the Lumbar curve?

L3-4 disk

21

What range (in degrees) should the lumbar curve measure?

20-60 degrees

22

T/F: An increase in the sacral base angle will result in more weight bearing responsibility on the facets.

True; increasing the sacral base angel with an anterior pelvic tilt results in an increase in the lumbar lordosis which places more weight on the facets.

23

T/F: An increase in the sacral base angle will result in more weight bearing responsibility on the disc which will decrease the spine's ability to absorb the axial compression forces.

False; A decrease in the sacral base angle will do this as it decreases the lumbar lordosis

24

What muscle is the major stabilizer of the L/S?

Quadratus lumborum

25

What motions are restricted in by the ALL and PLL? Which is more well developed?

Restrict excessive flexion/extension;
ALL>PLL

26

T/F: The lumbodorsal fascia acts like a large flexor retinaculum to constrain long tendons of thoracic and lumbar muscles.

False; acts as a large extensor retinaculum constraining thoracic and lumbar extensors

27

What ligament of the L/S guards against posterior shear, assists facet joints to remain in contact/gliding with rotation, and acts like a collateral ligament controlling vertebral rotation to follow an arc through flexion range?

Interspinous ligament

28

What motion does the supraspinous ligament provide resistance against?

excessive forward flexion

29

T/F: The facet capsule is well developed in the L/S, restricting joint flexion and distraction of facet surfaces during axial rotation.

true

30

What are the 3 pelvic joints?

2 SI joints and the pubic symphysis

31

T/F: SI joints are immobile syndesmotic joints.

False; they are mobile diarthrodial joints (though they were once thought to be immobile syndesmotic)

32

What are the main responsibilities of the pelvic joints?

support for the trunk, guide movement, and help to absorb the compressive forces associated with locomotion and weight-bearing

33

What is the keystone effect of the sacrum?

the sacrum is triangular and serves as a keystone in the arch between the two columns formed by the lower extremities effectively distributing axial compressive forces

34

When do the SI joint surfaces begin to roughen and develop their characteristic grooves and ridges?

teen years

35

What are the 2 most common pelvic types?

gynecoid and android

36

What are the 4 main ligaments of the pelvis?

Sacrospinous, anterior sacroiliac, sacrotuberous, and posterior sacroiliac ligaments

37

T/F: Although the SI joint was once thought to be immobile, it is now universally accepted as a movable joint, how it moves, how much it moves, and where axes of motion are located.

False; there is still a lot of controversy about the SI joint

38

T/F: The SI joint is most active while maintaining erect posture.

False; most active during locomotion

39

What direction does an innominate move as it flexes?

posteriorly and inferiorly

40

Which way does the sacral base move during nutation? counternutation?

anteriorly and inferiorly;
posteriorly and superiorly

41

T/F: The proposed axes of motion in the SI articulation allow a "gyroscopic" figure-4 movement.

False; figure-8 movement

42

T/F: Flexion of the SI joint incorporates anterior and superior movement of the PSIS and ipsilateral posterior and superior movement of the sacral base (counternutation).

False; this is true of extension

43

T/F: The Quadratus lumborum, erector spinae, gluteus maximus, gluteus minimus, piriformis, iliacus, and latissimus dorsi muscles all cross the SI joint.

False; no muscle crosses the SI joint, but all of these muscles listed have fibrous expansions that blend with the anterior and posterior SI joint ligaments which contributes to the strength of the joint capsule and ligaments.

44

T/F: the muscles impacting the SI joints help provide mobility.

False; provide stability, not mobility

45

If the left ilium has a PIEX listing, what orthogonal directions has it moved?

-thetaX and -thetaY

46

If the right ilium has an ASIN listing, what orthogonal directions has it moved?

+thetaX and -thetaY

47

If the left ilium has an ASIN listing, what orthogonal directions has it moved?

+thetaX and +thetaY

48

If the sacrum has a base posterior listing, what orthogonal direction has it moved?

-thetaX

49

If the sacrum has an SAL listing, what orthogonal direction has it moved?

+thetaZ

50

If the sacrum has a P-R listing, what orthogonal direction has it moved?

-thetaY