Spine

Question 0

What are the two types of curvatures and where are they located?

Answer 0

1. Primary curvature - thoracic and sacral

2. Secondary - cervical and lumbar

Question 1

What are the two main functions of the spine?

Answer 1

Mobility and stability

Question 2

What is the shape of the primary curves?

Answer 2

Posteriorly convex (C)

Question 3

What is the shape of the secondary curves?

Answer 3

Anteriorly convex (backwards C)

Question 4

What is kyphosis and what area of the spine does it occur?

Answer 4

Flexed posture - primary curves

Question 5

What is lordosis and what area of the spine does it occur?

Answer 5

Extended posture - secondary curves

Question 6

What is the function of the curves?

Answer 6

Acts like a spring to resist higher compressive loads

Question 7

What is the function of the vertebral body?

Answer 7

Weight bearing - resists compressive forces

Question 8

What is the orientation of the lines in the vertebral body?

Answer 8

Vertical

Question 9

What comprises the neural arch?

Answer 9

Pedicles and the posterior elements (everything except the vertebral body)

Question 10

What are the posterior elements of the neural arch?

Answer 10

1. Laminae
2. Articular processes
3. Spinous processes
4. Transverse processes

Question 11

What is the function of the laminae?

Answer 11

Protects the spinal cord and assists in bending forces

Question 12

What is the roof of the neural arch?

Answer 12

Laminae

Question 13

What is the pars interarticularis?

Answer 13

Part of the laminae - between the articular processes

Question 14

How many articular processes does each vertebral body have?

Answer 14

2 superior and 2 inferior facets

Question 15

What is the function of the spinous and transverse processes?

Answer 15

Increase the lever arm (regarding muscles)

Question 16

What is the function of the pedicles?

Answer 16

Transmit tension and bending forces

Question 17

How do the size of the pedicles change in the vertebrae?

Answer 17

Increase in size from the cervical to the lumbar regions

Question 18

What is the function of the angle of the neural arch?

Answer 18

Transmits torsion forces

Question 19

What is the function of the intervertebral (IV) disc?

Answer 19

Increases motion and transmits the load - compression, shock absorption, and movement

Question 20

What are the three components of the IV disc?

Answer 20

1. Nucleus pulposus
2. Annulus fibrosus
3. Vertebral end plate

Question 21

What is the cartilaginous end plate attached to?

Answer 21

Annulus

Question 22

Where is hyaline and fibrocartilage distributed with regards to the cartilaginous end plate?

Answer 22

Hyaline cartilage - closer to the end plate (vertebral body)

Fibrocartilage - closer to the disc

Question 23

How does the cartilage change as we age?

Answer 23

When we are young, we have more cartilage in our end plate, but as we age, we get more fibrocartilage to counteract the weight of gravity and respond better to compression

Question 24

What is the nucleus pulposus mostly comprised of?

Answer 24

Water (70-90%)

Question 25

What type of collagen does the nucleus pulposus contain and what is the function?

Answer 25

Type II collagen - resists compression

Question 26

When does the nucleus pulposus deform?

Answer 26

When it is compressed or when the walls stretch

Question 27

How does the nucleus pulposus move with compression?

Answer 27

Compression on the front of the disc moves the nucleus pulposus back and vice versa

Question 28

What happens during disc herniation with regards to pain?

Answer 28

When a disc is herniated, there is compression on the front of the disc pushing the nucleus pulposus to the back and impinging on the spinal cord Annulus is being torn and pushed forward

Question 29

How do people with herniated discs like to be?

Answer 29

Extended - they do not like to bend over

Question 30

What type of collagen does the annulus have and what is the function?

Answer 30

Type I collagen - resists tensile forces

Question 31

What does the annulus attach to?

Answer 31

End plate

Question 32

What is the orientation of the annulus fibers?

Answer 32

Each layer is perpendicular but oriented diagonally in a criss-cross pattern

Question 33

What is the purpose of the criss cross pattern of the annulus?

Answer 33

Provide more strength

Question 34

What two directions stress the annulus the most?

Answer 34

Flexion and rotation

Question 35

How thick are the cervical and lumbar discs?

Answer 35

Cervical - 3 mm | Lumbar - 9 mm

Question 36

What are the discs larger in the lumbar region?

Answer 36

More compressive loads in the lumbar region

Question 37

What is the relationship between disc thickness and vertebral body height?

Answer 37

Greater ratio yields greater movement

Question 38

Where is the greatest motion and why?

Answer 38

Cervical region - little vertebral body with a fairly large disc

Question 39

How does the IV disc receive nutrition?

Answer 39

Osmosis

Question 40

Why can't discs heal themselves very well?

Answer 40

No blood supply from the major arteries

Question 41

What part of the IV disc is innervated?

Answer 41

Outer 1/3 to 1/2 of the annulus

Question 42

How many DOF does the interbody joints have?

Answer 42

6

Question 43

What are the DOF of the interbody joints?

Answer 43

1. Gliding 2. Distraction and compression 3. AP translation 4. Lateral tilting 5. Rotation 6. AP tilting

Question 44

What joints contain the meniscus?

Answer 44

Facet joints

Question 45

What is the function of the meniscoids?

Answer 45

Aid in cushion - exist because the meniscus does not cover the whole part of the bone

Question 46

How are the facet joints oriented in each of the regions?

Answer 46

1. Cervical - transverse plane 2. Thoracic - frontal plane 3. Lumbar - sagittal plane

Question 47

What motions occur in the cervical region?

Answer 47

All motions - some limitation with rotation and side bending

Question 48

What motions occur in the thoracic region?

Answer 48

Side bending and slight rotation - no flexion and extension

Question 49

What motions occur in the lumbar region?

Answer 49

Extension and flexion - rotation and some flexion is limited

Question 50

What is the strongest facet joint?

Answer 50

Thoracic region - due to joint stress

Question 51

What is the importance of the kinematics coupling motion?

Answer 51

One motion about an axis occurs with another motion around a different axis - rotation and lateral flexion are coupled movements

Question 52

Describe the coupling motion in the cervical region.

Answer 52

Right rotation occurs with a right side bend

Question 53

Describe the coupling motion in the thoracic and lumbar region.

Answer 53

Right rotation occurs with a left side bend but with FLEXION, side bending and rotation occur to the SAME side

Question 54

What occurs during flexion?

Answer 54

Anterior glide and tilt

Question 55

During what movement do the foramen increase in size?

Answer 55

Flexion

Question 56

During flexion, describe the compression on the annulus?

Answer 56

Anterior annulus compresses and the posterior annulus stretches (opposite during extension)

Question 57

What occurs during extension?

Answer 57

Posterior glide and tilt

Question 58

What occurs during lateral flexion?

Answer 58

Lateral tilt, rotation, and translation

Question 59

During lateral flexion, describe the size of the foramen.

Answer 59

Right side bend would decrease the size of the foramen on the R side and increase the size of the foramen on the L side

Question 60

During lateral flexion, describe the compression of the annulus.

Answer 60

Annulus compressed on concave side and stretched on convex side

Question 61

What motion does the annulus limit?

Answer 61

Rotation

Question 62

What percentage does the facet joints compress?

Answer 62

0-33%

Question 63

How is the load transmitted through the vertebrae?

Answer 63

Superior end plate to inferior end plate

Question 64

What can cause buckling of the annulus?

Answer 64

Sustained load

Question 65

What does the nucleus pulposus try to do during compression?

Answer 65

Expand outward toward the annulus

Question 66

How is the nucleus pulposus fluid changed with compression and distraction?

Answer 66

Compression - fluid is released | Distraction - fluid is absorbed