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PTRS 845 Midterm > Discs > Flashcards

Flashcards in Discs Deck (70):
1

Function and Composition: Nucleus Pulposus

F: accepts compressive forces; allows deformation under pressure 

C: 70-90% water, 15-20% collagen type II, 65% proteoglycans (dry weight)  < GEL like substance

2

Term: Causes nucleus pulposus to be viscose and thick

Collagen type 2

3

Function and Composition: Annulus Fibrosus

 

F: Resist distraction, shear, and torsional stresses

C: 60-70% water, 50-60% type I collagen, 20% proteoglycan (dry weight)

4

Term: sheets

Lamellae

5

Describe the arrangement of lamellae of the annulus fibrosus

Arranged in concentric rings with the fibers alternating 60 degrees from vertical in successive layers

6

Annulus Fibrosus Structure: Allows for flexion motion

Thin posterior fibers

- While thin allows them to be more tightly packed thus can withstand flexion while remaining flexible 

7

Annulus Innervation

Only the outer 1/3 is innervated (by recurrent sinuvertebral n.)

 

B/c the annulus is innervated it can be a source of LBP

8

Term: Outer annulus fibers that are attached to the vertebral bodies

Sharpey's Fibers

9

Function: Vertebral end-plate

Hold disc in place 

10

Describe the effect of nerve ending proliferation

increased pain

It has been found that those with DDD have more end plate innervation 

11

Structure: 

- Transmits load form one vertebra to the next

- Allows movement between vertebra

- Proprioception

Intervertebral Disc

12

2 Normal Forces that Occur to Discs

1. Compression

2. Distraction

13

2 Pathologic Forces that Occur to Discs

1. Rotation

2. Shear

14

Describe the Mechanics: Compression

The vertebral bodies move towards one another deforming the nucleus and placing pressure on the annulus (radial bulging) and end plates (bulge into trabecular bone)

 

The annulus and trabecular bone resist the pressure, equilibrium is reached and the load is transfer through the spine

15

Term: Principle WB component of L-spine

Interbody joint

16

Term: movement caused by WB activities or muscle forces

Axial compression

17

Indicates: Pain with traction of the spine

Annulus tear or facet issue 

18

Describe the Annulus' response to rotation

Half of the fibers are on stretch and half are lax due to alternating directions of lamella 

19

Motion: Causing lateral shearing and lateral rotation

Lift and twist

^ You should lift and pivot instead

20

Term: Anterior/Posterior bending

Rocking

21

Describe why those with posterior disc bulges flex or rock anteriorly

An anterior rock increases pressure on the anterior nucleus and decreases pressure on the posterior nucleus effectively relieving some of the pressure off the disc bulge

22

2 Ways the Disc recieves Nutrition

1. Passively - imbibition/diffusion

2. Actively - spinal motion 

23

Term: avascular structure

Vertebral Disc

24

Describe the pattern of diffusion of nutrients (for the discs)

Bone marrow > vertebral body > end plate > nucleus 

25

describe the blood supply/flow surrounding the discs

Blood supply to outer 1/3 of annulus from spinal arteries

Blood flow through endplate from bone marrow 

26

Optimal Stimulus for Regeneration: Annulus

Modified tension in line of stress 

Unload position out of pain range

27

Optimal Stimulus for Regeneration: Nucleus Pulposus

Intermittent compression and decompression

28

Describe Normal Disc Degeneration

Disc integrity decreases with age

The ability to retain water and distribute load across the disc decreases

All 3 structures under go change

 

PAIN is NOT a part of normal disc degeneration

29

4 Biochemical Disc Changes with Age

1. Decreased proteoglycan (can't hold water - dry out)

2. Increased or change in collagen type (annulus > Type 2 = can't accept tensile forces)

3. Dead cell build up > lysozome activity > weakened collagen

4. Amyloid build up in discs

30

Changes in Disc Nutrition with Age

1. Lack of movement > decreased diffusion

2. Decreased fluid transport

3. Injury or trauma

31

Force: Most disruptive to a disc

Shear

32

Condition:

- M > F

- 40-50

- Occupation involves lifitng, sitting, oversure

Degenerative Disc Disease

33

Condition:

- Constant or Intermittent pain

- Low grade ache

- Leg sx rare

- Morning stiffness/pain

- Localized in low back, rare for pain to radiate

Degenerative Disc Disease

34

Describe why those with DDD have morning stiffness

Over night discs rehydrate, making them highly hydrated in the morning.  This increases their size, decreasing the space in the joint and contributing to morning stiffness

35

Condition:

Aggravating factors include

- Extending

- Bending

- Sitting

- Sit to stand

- sustained posutre

- sudden motion

- end ROM

Degenerative Disc Disease

36

Condition:

History includes repeated micro trauma to annular fibers, trauma to disc, or bone spur formation

Degenerative Disc Disease

37

Condition:

Objective

- ROM limited in the acute phase

- Pain with flex/ext, OP, sustained posture

 

Degenerative Disc Disease

38

Condition: 

Objective

- SLR (-)

- Thickened soft tissue

- PAIVM increased, decreased mobility, min pain  

Degenerative Disc Disease

39

4-6 Goals for Degenerative Disc Disease

 

1. Decrease compression

2. Promote nutrition

3. Improve mobility/flexibility

4. Strengthen core

5. Minimize faulty movement

6. Promote function

40

4 Components of Disc Rehydration

1. Unloaded 90/90 positin or alternative reclined position

2. Minimum mm activity

3. Maintain unloaded position for 15-20 minutes

4. Morning exercise prefered to DDD

41

Term: displacement of nuclear material beyond normal confines

Disc Herniation

42

4 Types of Disc Herniation

1. Intra-spongy herniation

2. Protrusion (contained herniation)

3. Prolapse/Extrusion

4. Sequestration 

43

Term: break in the end plate due to heavy lifting or compression that may or may not result in an inflammatory response

Intra-spongy herniation 

44

Defn: Schmorl's Node

A hole in the vertebral body due to trabecular bone erosion 

 

Erosion can occur following an intraspongy herniation due to nuclear material settling into trabecular bone 

45

Condition:

- Occurs more commonly in the T-Spine

- 20s-30s

- Pt. unloads spine before getting up

Intra-Spongy Herniation

46

Term: Nucleus material migrates outward through a tear but does not escape from the outer annulus fibrosus or the PLL

Protrusion 

47

Condition:

- 20s-50s

- Poorly localized dull ache in back 

- May have buttock pain

- Increased pain in AM

- Unloads spine from sit to stand

Protrusion

48

Condition:

History includes sudden onset of localized back pain that may resolve with continued activity

Protrusion

49

Describe why herniation is not longer possible after the age of 55 

The nucleus losses its viscosity so doesn't have a consistency that would make it easy for it to escape its confines

50

Condition:

Objective

- Lateral shift

- Radicular pain +/--

- flexion limited or painful 

Protrusion

51

Term: trunk deviation away from the pain

Lateral Shift

52

Term: Nucleus material escapes the annulus fibrosus and the PLL but remains attached to the disc

Extrusion or Prolapse

53

Term: A free fragment of the nucleus pulposus  and may migrate to the spinal canal

Sequestration

54

2 Disc Herniations that are likely to Impinge Nerve Tissue

1. Extrusion/Prolapse 

2. Sequestration 

55

Term: Bulge lateral to the nerve root

Posterolateral Disc Herniation

56

Term: Shift to opposite side to open up and allow pressure release

Protective Scoliosis for Posterolateral Disc Herniation

57

Term: Most common disc herniation

Posterolateral Disc Herniation

58

Term: Bulge medial to the nerve root

Posteromedial Disc Herniation

59

Term: Shift to the same side to open up and allow pressure release

Protective Scoliosis for Posteromeidal Disc Herniation

60

Condition:

- 20-55 yo

- LBP, back and leg pain

- Associated muscle spasms +/-

 

Posterolateral Disc Herniation

61

Condition:

Aggravating factors include: flexion, sitting, sit to stand, walking, sneezing, coughing

Posterolateral Disc Herniation

62

Condition: Those with Posterolateral Disc Herniation are at high risk

Cauda Equina 

63

Condition

- Severe back pain

- SLR +

Possible Cauda Equina

64

Condition: 

History includes: sudden onset but usually due to repetitive bending, lifting or frequent lifting, recurrent episodes

Posterolateral Disc Herniation

65

Condition:

- Slight flexed posture

- Lateral Shift +/-

- Limited ROM/Gaurded movement

- Centralization of pain 

Posterolateral Disc Herniation

66

4-6 Goals for (Posterolateral) Disc Herniation

1. Decrease Inflammation/mm gaurding

2. Protect Disc

3. Centralize Pain

4. Correct shift if present

5. Decrease compressive forces and tension

6. Promote pain free mobility/activity 

67

Describe how lateral shift is named

Named in the direction of shoulder displacement

 

A left shift will relieve sx on the right

68

Describe how a lateral shift is correct

By moving the hips under the shoulders

69

Describe what will be damaged first with pure compression

Vertebral bodies and end plate before disc damage

70

Term: most frequent site of disc degeneration

Lumbosacral joint - L4/L5; L5/S1