Vertebral Column

Question 1

Functions of the vertebral column

Answer 1

1)support weight 2)protect spinal cord 3)serve as axis and pivot 4)aid posture/movement

Question 2

5 differentiated segments of vertebral column

Answer 2

-7 cervical -12 thoracic -5 lumbar -5 sacral -variable coccygeal vertebrae (typically 4)

Question 3

Vertebral Body

Answer 3

Question 4

Vertebral/Neural Arch

Answer 4

paired laminae & pedicles

-pedicles = join vertebral arch and body

laminae = flat plates contacting pedicles

vertebral foramne = forms vertebral canal

superior and inferior vertebral notches, form IV foramina

Question 5

Vertebral processes

Answer 5

spinous process - 1 per vert

transverse - 2 per vert

articular process/zygapophysis - 4 per vert - 2 superior (pre-zygapophyses) and 2 inferior (post-zygapophyses)

Question 6

Characterstics of Cervical Vertebrae

Answer 6

• transverse foramina - convey vertebral arteries
• anterior & posterior tubercles - on transverse processes
  
  • carotid tubercle - anterior tubercle of C6
• vertebral foramina - large for C3-C7 because of cerbical enlargement of the cpinal cord
• uncinate process - raised margins of superior border of body
• C1/atlas
  
  • articulates with occipital condyles
  • lacks vertebral body
  • groove for vertebral artery on superior surface
• C2/axis
  
  • dens/odontoid process - former body of C1, and pivot for skull
• C7/vertebral prominens - long spinous process

Question 7

Characteristics of Thoracic Vertebrae

Answer 7

costal facet, for rib hear

costal facet, for rib tubercle

spinous process - long and slender

Question 8

Characteristics of lumbar vertebrae

Answer 8

• accessory process - posteriorly on each transverse process, attachment for intertransverse lumborum muscles
• mamillary process - attachments for multifidus and median intertrransverse muscles
• L5
  
  • largest vertebrae in column
  • huge contributor to lumbosacral angle
    
    • lumbosacral angle = angle between lumbar and sacral vertebrae

Question 9

Characteristics of Sacral Vertebrae

Answer 9

• sacral vertebrae fuse to form sacrum
• functions to transfer body weight to pelvis and contriubute to strenth and stability
• sacral canal - sacral continuation of vertebral canal
• sacral formina - between vertebrae
• sacral promontory - anterosuperior projecting ednge of S1
• median crest - fused spinous processes
• medial crest - fused articular processes
• lateral crest - fused transverse processes
• sacral hiatus - gap in laminae
• sacral cornua - former inferior articular processes of S5
• auricular surface - part of sacroiliac joint

Question 10

Characteristics of Coccygeal Vertebrae

Answer 10

• rudimentary tailbone
• coccygeal conrua (horns) = part of Co1, articulate with sacral horns

Question 11

Curvatures of the Vertebral Column

Answer 11

• Cervical - anteriorly convex, secondary
• Thoracic - anteriorly concave, primary
• Lumbar - anteriorly convex, secondary
• Sacral - anteriorly concave, primary

Question 12

Types of curvatures

Answer 12

• Primary
  
  • present at birth
  • due to differences in A&P portions of vertebrae
• Secondary
  
  • primarily developed after birth
  • due to differences in A&P portions of IV discs

Question 13

Movements of the Vertebral Column

Answer 13

• Movements:
  
  • Flexion/extension
  • lateral bending & rotation
• Restricted by:
  
  • IV discs
  • orientation of zygapophysial joints, articular capsules, muscles & ligatments
• range of motion results primarily from elasticity of IV discs

Question 14

Clinical conditions of vertebral column

Answer 14

• Degenerative changes in vertebrae
  
  • i.e. osteoporosis and osteoarthritis
• Abnormal curvature:
  
  • i.e. kyphosis, lordosis, scoliosis

Question 15

Vertebral Body Joints

Answer 15

• Secondary cartilaginous joints
• articulate via interposed IV discs
• IV discs
  
  • Anulus fibrosis - outer portion of concentric fibrocartilaginous cicles
  • nucleus pulposus - slightly posteriourly positioned gelatinous, elastic, avascular core

Question 16

Uncovertebral joints

Answer 16

joints between uncinate process of C3-C6 and superjacent body

Question 17

Vertebral arch joints (zygapophyses)

Answer 17

• synovial joints between superior and inferior articular processes
• allow gliding betwen vertebrae
• variable orientation limits movements

Question 18

Longitudinal Ligaments

Answer 18

• Anterior longitudnal Ligament
  
  • strong band extending across anterolateral vertebral bodies and IV discs
  • prevents hyperextension of vertebral column, stabilizes vertebral body joints
  • extends from sacrum to occiput & C1’s anterior tubercle
• Posterior longitudinal ligament
  
  • weaker band extending along anterior aspect of vertebral canal
  • prevents hyperflexion of vertebral column
  • prevents herniation/protrusion of discs

Question 19

Acessory Ligaments

Answer 19

• Ligamentum Flava
• Interspinous ligaments
• supraspinous ligaments
• Nuchal ligament/ligamentum nuchae
• Inter-transverse ligaments

Question 20

Ligamentum Flavum (acessory)

Answer 20

• “yellow ligaments”
• connect adjacent laminae
• broad, yellow fibrous tissue extending along prosterior wall
• prevents abrupt flexion of vertebral column

Question 21

Interspinous ligaments (accessory)

Answer 21

connect spinous processes

Question 22

supraspinous ligaments (accessory)

Answer 22

connect tips of spinous processes

extends from C7 to sacrum

merges with ligamentum nuchae

Question 23

nuchal ligament/ligamentum nuchae (accessory)

Answer 23

extends from external occiputal protuberance/posterior foramen magnum to spinous processes of cervical vertebrae

Question 24

inter-transverse ligaments (accessory)

Answer 24

connects adjacenet transverse proceeses

obvious in thorax

Question 25

Craniovertebral Joints

Answer 25

1. atlanto-occipital joint 2. atlanto-axial joint

Question 26

Atlanto-occipital joint Movement

Answer 26

* primariliy allows nodding of head (flex/ext) * allows lateral bending and rotation

Question 27

atlantooccipital membranes

Answer 27

extend from atlas to margins of foramen magnum prevents excessive movement

Question 28

Cruciate Ligament

Answer 28

* Composed of: * Transverse ligament of atlas * holds dens of C2 with arch of C1 * posterior wall of dens' socket * Longitudinal bands * extend from transverse ligament to occiput and C2 body

Question 29

Alar ligaments of atlanto-occipital joint

Answer 29

extend from sides of dens to C1 & foramen magnum limits head rotation

Question 30

tectorial membrane of atlanto-occipital joint

Answer 30

extends from C2 and through foramen magnum suprior continuation of posterior longitudinal ligament

Question 31

Atlant-axial Joint

Answer 31

* Joint between atlas & axis (2 lateral, 1 median) * movement is primarily rotation * C1 & skull rotate on C2, limited by alar ligaments * C1/C2 zygapophysial joints = gliding joints * dens & C11 articulation = pivot joint

Question 32

Clinical conditions of Vertebral Joints & Ligaments

Answer 32

* Herniations and protrusions of nucleus pulposus * Internal Decapitation

Question 33

Spinal Arteries

Answer 33

* Branches of: * vertebral & ascending cervical arteries - in neck * posterior intercostal arteries - in thorax * subcostal & lumbar arteries - in abdomen * iliolumbar & lateral & medial sacral arteries - in pelvis * Enter into IV foramina & divide into: * terminal radicular arteries supplying ventral and dorsal roots * medullary segmental arteries, which anastomose with spinal arteries

Question 34

Spinal Veins

Answer 34

* Anterior & posterior components for each: * internal venous plexus * external venous plexus

Question 35

Initial Vertebral Development

Answer 35

* involves sclerotomes, paired mesenchymal condensations around notochord * part moves to form IV disc * part forms mesenchymal centrum/futue vertebral body * each centrum forms from 2 adjacent scelrotomes and becomes intersegmental * notochord degenerates where surrounded by vertebral bodies * notochord form nucleus pulposus between vertebral bodies * the portion around neural tube forms neural arch * mesenchymal cells in body wall from form ribs

Question 36

Chondrificaiton

Answer 36

* Development of cartilaginous vertebral column * Several chondrification centers: * 2 fuse to form cartilaginous centrum * 2 centers fuse to form neural arch, then arch fuses with body * Neural arch centers also produce spinous and transverse processes

Question 37

Ossification

Answer 37

* Development of bony vertebral column * Primary ossification centers in each cartilaginous vertebrae: * 2 fuse to form centrum * 2 form vertebral arch * Secondary ossification centers * tip of spinous process ( 1 per vert) * tip of transverse processes (2 per vert) * annular epiphyses on superior and inferior rims of body (2 per vert)

Question 38

Clinical Conditions of Spinal Development

Answer 38

Spina bifida