Ch 4 - MSK: Spine Flashcards
What is the clinical course of disability and ability of return to work in low back pain?
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
What are the red flags of low back pain?
Myelopathy/cauda equina: Gait ataxia, UMN changes, Bowel/bladder/sexual dysfunction
Tumor: night pain, wt loss
Infection: fever, chills
What is the expected return to work expectation based on time missed from work?
6 mo: 50%
1 yr: 25%
2 yr: 0%
What are joints of Luschka?
As cervical discs degenerate, raised margins approximate with the body of the superior vertebra l/t degenerative joint change which limit lateral translation
What is the orientation of facet joints?
• 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
Describe facet joint innervation.
- Cervical: MB at that level and the level below
* Thoracic and lumbar: MB of that level and the above level
What is the nucleus pulposus?
Viscous mucoprotein gel mixture of water and proteoglycans in a network of Type II collagen that braces the annulus to prevent buckling
What is the annulus fibrosus?
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.
Describe the innervation of discs.
Outer 1/3 of disc that contains the annulus fibrosis receives dual innervations from ventral rami
Nucleus pulposus lacks innervations
What does aging increase in discs?
Nuclear water content
Ratio of chondroitin: keratin
Proteoglycan molecular weight
What does aging decrease in discs?
Fibrous tissue
Cartilage cells
Amorphous tissue
What does the ventral primary rami innervation?
Trunk musculature
Plexus contributions
What does the dorsal primary rami innervation?
Lateral: Iliocostalis, skin
Intermediate: Longissimus
Medial: Multifidi, rotators, interspinalis, intertransversarii, posterior spinal ligaments, zygapophyseal joints
What does the sinuvertebral nerve innervation?
Posterior longitudinal ligament
Posterior disc
Anterior dura
Vertebral body
What does the Anterior longitudinal ligament (ALL) prevent?
Limits hyperextension and forward movement