Ch 4 - MSK: Spine

Question 1

What is the clinical course of disability and ability of return to work in low back pain?

Answer 1

Generally improve in 1 month, but 1/3 may have persistent discomfort for up to a year after injury, with 20% of those reporting limitation in activity

Question 2

What are the red flags of low back pain?

Answer 2

Myelopathy/cauda equina: Gait ataxia, UMN changes, Bowel/bladder/sexual dysfunction
Tumor: night pain, wt loss
Infection: fever, chills

Question 3

What is the expected return to work expectation based on time missed from work (spine)?

Answer 3

6 mo: 50%
1 yr: 25%
2 yr: 0%

Question 4

What are joints of Luschka?

Answer 4

As cervical discs degenerate, raised margins approximate with the body of the superior vertebra l/t degenerative joint change which limit lateral translation

Question 5

What is the orientation of facet joints?

Answer 5

• Cervical:
 – AA/OA joints: no true facet joints 
 – C3–C7: frontal plane
• Thoracic facets: frontal plane
• Lumbar facets begin in sagittal plane and progress to the frontal plane at L5–S1

Question 6

Describe facet joint innervation.

Answer 6

• Cervical: Medial branches at that level and the level below
• Thoracic and lumbar: Medial branches of that level and the above level

Question 7

What is the nucleus pulposus?

Answer 7

Viscous mucoprotein gel mixture of water and proteoglycans in a network of Type II collagen that braces the annulus to prevent buckling

Question 8

What is the annulus fibrosus?

Answer 8

Type I collagen fibers arranged in obliquely running lamellae that encase the nucleus pulposus and are attached to the vertebral endplate plates. Withstands distraction and bending but weaker for torsional stresses.

Question 9

Describe the innervation of discs.

Answer 9

Outer 1/3 of disc that contains the annulus fibrosis receives dual innervations from ventral rami
Nucleus pulposus lacks innervations

Question 10

What does aging increase in discs?

Answer 10

• Nuclear water content
• Ratio of chondroitin: keratin
• Proteoglycan molecular weight

Question 11

What does aging decrease in discs?

Answer 11

Fibrous tissue
Cartilage cells
Amorphous tissue

Question 12

What does the ventral primary rami innervate?

Answer 12

Trunk musculature

Plexus contributions

Question 13

What does the dorsal primary rami innervate?

Answer 13

Lateral: Iliocostalis, skin
Intermediate: Longissimus
Medial: Multifidi, rotators, interspinalis, intertransversarii, posterior spinal ligaments, zygapophyseal joints

Question 14

What does the sinuvertebral nerve innervate?

Answer 14

Posterior longitudinal ligament
Posterior disc
Anterior dura
Vertebral body

Question 15

What does the Anterior longitudinal ligament (ALL) prevent?

Answer 15

Limits hyperextension and forward movement

Question 16

What does the Posterior longitudinal ligament (PLL) prevent?

Answer 16

Prevents hyperflexion of the vertebral column