L5 Lumbar Spine and Back

Question 1

vertebral column and spinal nerve correlation

Answer 1

• in the cervical and thoracic region,s, correlation is pretty close
• in lumbrosacral regions, spinal nerves are far superior (especially in the lower lumbar region) than the vertebrae

Question 2

typical vertebrae

Answer 2

• vertebral body (anterior)
• common features: increasing vertebral body size distally
• pedicle and laminae connect to create vertebral (neural) arch
• vertebral canal: houses spinal cord and protective/supportive structures

Question 3

thoracic vertebrae

Answer 3

• three costal facets
  
  • superior and inferior: posterior of vertebral body
  • transverse: on transverse process
• spinous process → no extension of thoracic joints
• articular processes → coronal ∴ no flexion/extension

Question 4

joints of thoracic vertebrae

Answer 4

• 3x costal articulaitons (2 on the same number and 1 superior)
• many capsular ligaments → no movement (only minor rotation of ribs)
  
  • joints are for force dissipation

Question 5

lumbar vertebrae

Answer 5

• “typical vertebrae”
• bigger and thicker than other segments
• most vulnerable: no osseous tissue, just soft tissue ∴ easy for pathology to occur
• bigger vertebral body
• sagittal articular facets ∴ flexion & extension can occur

Question 6

sacrum and coccyx

Answer 6

• fused together
• openings on dorsal and ventral sides → different things go out of different sides
  
  • dorsal: nerves
  • ventral: nerves and veins
• promontory pushes out anteriorly

Question 7

sacroiliac joint

Answer 7

• sacral connects to iliac bone via sacroiliac joint
• moveable joint → moves when walking
• sacroiliac pain could potentially show as lower back pain

Question 8

nuclear herniation

Answer 8

• “hole in the wall” where it shouldn’t exist

Question 9

Answer 9

Question 10

Answer 10

Question 11

Answer 11

Question 12

vertebral movement as determined by articular facet orientation

Answer 12

• skull + C1 (atlas) = atlanto-occipital joint: covex (occipital) + concave (atlas) = flexion and extension
• C1 (atlas) + C2 (axis) = atlanto-axial joint: almost transverse = rotation
• cervical (C2→C7): oblique (45° b/w transverse and coronal plane) = flexion/extension, lateral flexion, rotation
• thoracic: almost coronal = limited rotation
• lumbar: almost sagittal = flexion/extension and lateral flexion

Question 13

zygapophyseal joints

Answer 13

• determine range of intervertebral motion
• high risk of degenerative disease - would be felt at an indefinite spot as there are many different branches of nerves and brain prioritises information

Question 14

arterial supply to the vertebral column

Answer 14

• segmental - go to word, at every level multiple branches of arteries enter the vertebral column
• anterior: 1 x anterior spinal artery
• posterior: 2 x posterior spinal arteries
• anastomoses are present

Question 15

venous supply to the vertebral column

Answer 15

• also segmental
• epidural veins (in epidural fat):
  
  • posterior internal vertebral venous plexus
  • anterior internal vertebral venous plexus
• anastomoses occur
• veins in sacral region can be entry pathway of diseases into the brain - veins in the brain have low pressure → slow highway to the brain

Question 16

embryonic development of the vertebral column

Answer 16

1. condensation of mesenchymal tissue
2. chondrification of mesenchymal tissue (turns to cartilage), becomes cartilaginous template for bone and covers neural tube tissues
3. begin ossification (primary ossification centres), leaves bone with bits of tissue stuck to it for:
   
   • processes (joints)
   • muscle attachment areas
   • vertebral disc

Question 17

What can occur due to vertebral column defects in embryogenesis?

Answer 17

• congenital scoliosis: two cores of centra fail to fuse (vertebral body), causes lateral curvature of the spine
• spina bifida: halves of the neural arch failing to fuse

Question 18

spina bifida

Answer 18

• most common neural tube defect
• neural tube forms in most cases - supporting tissue does not
  
  • spina bifida occulta: defect covered with skin and often a patch of hair
  • spina bifida cystica: nerves and or meninges protruding throught the defect

Question 19

types of spina bifida

Answer 19

• spina bifida occulta: defect covered with skin and often patch of hair
• spina bifida cystica: nerves and/or meninges protruding through the defect
  
  • meninges only: meningocele
  • both neural tissue and meninges: meningomyelocele
  • rachischesis: failure of neural tube products to form in area of defect

Question 20

power movers of the back

Answer 20

• psoas major m.: merges distally with iliacus m. to become iliopsoas m. = most powerful flexor of the hip
• quadratus lumborum m.:“square of the lumbar” from iliac pelvis to lumbar vertebrae
• erector spinae mm.

Question 21

muscle layers of the back

Answer 21

• superficial extrinsic muscles
• intermediate extrinsic muscles
• intrinsic muscles
  
  • superficial
  • intermediate
  • deep

Question 22

Answer 22

Question 23

Answer 23

Question 24

innervation of trapezius m. and latissimus dorsi m.

Answer 24

• trapezius: accessory nerve (CN XI)
• latissimus dorsi: thoracodorsal nerve

Question 25

innervation of levator scapulae m. and rhomboideus major and minor muscles

Answer 25

dorsal scapular nerve

Question 26

Answer 26