Exam 2: Lumbar Spine Flashcards Preview

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Flashcards in Exam 2: Lumbar Spine Deck (83):
1

What are the main responsibilities of the lumbar spine

Bears large loads, used for powerful muscle actions, trunk mobility, significant biomehcanical needs

2

What are the characteristics of lumbar facets

Thick large and strong

3

The inferior articular processes of lumbars are ____ and face _____

Convex; anterolaterally

4

The superior articular processes of the lumbars are ____ and face ____

Concave; posteromedially

5

Lumbar facets lie primarily in what plane

Sagittal, becoming more coronal at lumbosacral joint

6

What is a developmental abnormality where one facet faces sagitally and the other facet faces coronally and where is it mc

Facet tropism mc L5-S1 then L4-L5

7

Facet configuration in the lumbars limits ____ and allows for greater _____

Limits rotational flexibility and allows for greater mobility in flexion and extension

8

Which lumbar facets have sagittal orientation and limit axial rotation (theta Y)

L1-L4 facets

9

Which facets are in a coronal orientation and limit posterior/anterior shear (z translation)

L5-S1 facets

10

The lumbar facets normally carry ___ of axial load and up to ____ in extension

18%; 33%

11

What is the primary movement in l/s

Flexion/extension

12

What percentage of trunk flexion/extension takes place in l/s

75%; twice as much flexion as extension

13

What is limited due to sagittal facet orientation

Axial rotation

14

Lateral bending is controlled primarily by what

Eccentric activity of the QL

15

Normal muscular activity leads to spinous processes rotation toward what

Side of lateral extension, spinous to ipsilateral side can switch at L4/L5

16

The nucleus of lumbar IVD are localized somewhat _____ in the disc

Posteriorly

17

What is the disc height to body height ratio of the lumbar IVD

1:3

18

The ratio of 1:3 in the lumbars allow more movement than ____ but less than ____ and gives the disc greater resistance to ____

T/s; c/s; axial compressive forces

19

Lumbar spinal canal contains enlargement of spinal cord proximally called what

Conus medularis and the cauda equina with spinal nerves distally

20

CNS is tethered to the coccyx by what

Filum terminale

21

Where does the spinal cord end

L2

22

After the spinal cord ends the nerve roots continue down the spinal canal as what

Cauda equina

23

Nerve roots in lumbars exit the dura how

Slightly above the foraminal opening

24

What does the exit of the nerve roots at the dura cause

Causes their course to be more oblique and length to increase

25

When does the secondary lumbar lordotic curve begin to develop

Starts developing 9-12 months of age/beginning to sit up

26

When does the secondary lumbar lordotic curve become established

When learning to stand at about 18 months

27

Where is the apex of the lumbar lordotic curve

L3/L4 disc

28

Normal lumbar lordosis should be how many degrees

20-60 degrees

29

Changes in the sacral base angle can influence the depth of what

A-P curves in the spine

30

Sacral base angle increase with what

Anterior pelvic tilt

31

Anterior pelvic tilt increases the sacral base angle and causes lumbar lordosis, and weight bearing responsibilities how

Increases the lumbar lordosis which places more weight bearing responsibility on the facets

32

The sacral base angle decreases with what

With posterior pelvic tilt

33

Posterior pelvic tilt causes a decrease in the sacral base angle resulting in what impact on lumbar lordosis and weight bearing responsibilities

Results in decrease in the lumbar lordosis placing more weight bearing responsiblity on the disc and decreases the spines ability to absorb axial compressive forces

34

What is the major stabilizer of the L/s

The quadratus lumborum

35

When is the QL most active

During heavy lifting but is active in flex/extend, and lateral bend

36

Identify when the QL is more active between heavy lifts, isometric lateral bending holds, during standing isometric twists

Heavy lifts> isometric lateral bend holds > during standing isometric twists

37

What ligaments restrict excessive flexion/extension

ALL/PLL

38

What ligament is highly elastic and acts as a barrier to material that would otherwise enncroach on the cord during range of motion

Ligamentum flavum

39

What ligament acts like a larger extensor retinaculum to constrain long tendons of thoracic and lumbar extensors

Lumbodorsal fascia

40

What ligament acts like a collateral ligament and controls vertebral rotation to follow an arc through flexion range, also assist facet to remain in contact with rotation

Interspinous

41

What ligament guards against posterior shear

Interspinous

42

What ligament provides resistance against excessive forward flexion

Supraspinous

43

What well developed ligament restricts joint flexion, restricts distraction of facet surfaces during axial rotation

Facet capusle

44

What is the cascade of ligament damage

Trauma causes damage leading to laxity leading to joint degeneration

45

Which is more resistant to compressive forces: IVD or posterior facets

IVD = 80% resist of axial force, posterior facets = 10% of axial forces

46

What loading causes a symmetric stress distribution on the IVD

Eccentric loading

47

How much increase is there in resistance to axial forces in flexion and extenion in posterior facets

Increase 5x in flexion, incrreases 3x in extension

48

There is significant increase in disc pressure with what type of sitting

Straightened or flexed sitting

49

What motion increases tensile force at the anterior annulus and increases loading and compression of the posterior facets with a 3x increase in posterior facet compression forces

Extension

50

What motion increase posterior annulus tensile forces and decreases the spines ability to absorb axial compression and 5x increase in A-P shear on the posterior facets

Flexion

51

What motion decreases disc inhibition and metabolism, reduces disc height and increases annulus stress, increases mechanical load to posterior joints

Static loading

52

What causes a spondylolisthesis

Defect of the pars interarticularis

53

Spondylolisthesis fracture may come from repeatedly alternating flexion and extension movements especially what

Hyper extension

54

Who and where is spondylolisthesis likely to occur

Usually at L5 in males

55

What spondy is developmental abnormality of neural arch resulting in deformity and anterior vertebral dispalcement

Congenital

56

What spondy class is a defect in pars interarticularis (stress fx) mc in younger paitents at L5

Isthmic

57

What type of spondy has segmentally instability secondary to advanced DDD and posterior DJD, mc in older patients (women over 60 esp) and typically occurs at L4

Degenerative

58

What type of spondy class is an acute fix involving neural arch but NOT pars interarticularis

Traumatic

59

What spondy type is an osseous deformity secondary to local or systematic pathology (pagets mets, osteoporosis)

Pathologic

60

What grades of spondy can we adjust

Grades 1/2

61

What is the grading system of spondy’s called

Meyerding grading system

62

How much movement means instability in a spondy

>3.5 mm of movement in flexion/extension

63

What fracture is a comminuted vertebral body fracture with disruption of the anterior and posterior walls of the VB

Burst fracture

64

What does a burst fracture cause

Sever neuro problems from retropulsion of bone into spinal canal

65

What causes a burst fracture

Results from high energy axial load like trafffic collision, high falls, seizures somtimes

66

What type of complex is the pelvic joint

3 joint complex

67

What type of joint is the SI

Mobile synovial joints

68

What do pelvic joints do

Support trunk, guide movement, help absorb the compressive forces with locomotion/weight bearing

69

Surface contours of the pelvis develop into what

Interlocking elevations and depressions

70

What type of effect does the pelvis produce on the sacrum

Keystone effect distributing axial compressive forces

71

At birth what are the joints of the SI like

Undeveloped, smooth, flat

72

After ____ the SI joint begins to take their adult characteristics

Ambulation

73

In the teen years what happens to the SI

The joint surfaces begin to roughen and develop characteristic grooves/ridges

74

In later year what pateints will have interarticular adhesions across the SI joints and have lost SI joint motion

Mostly males

75

When is the SI joints most activw

Locomotion in flex/extend along with hip joint

76

As the left innominate moves posteriorly/inferiorly the left sacral base moves how

Anteriorly/inferiorly (nutation)

77

As the right innominate moves anteriorly/superiorly, the sacral base moves how

Posteriorly and superiorly (counternutation)

78

The proposed axes of motion in the SI articulation allow what type of movement

Gyroscopic figure 8 movement

79

Is the SI joint crossed by muscle

No

80

What contributes to the strength of the joint capusle at SI and ligaments

The different muscles near the SI providing stability not mobility

81

What is the function of muscle at the SI

Not to generate motion but function as brace for the area and create stability for effective load transfer

82

What happens to theta x when saccrum apex goes posterior

Nutation = flexion malposition

83

What happens to theta x when saccrum base goes posterior

Counternutation = extension malposition