Axial skeleton: vertebrae
thoracic curvature
Convex posteriorly; forms before birth; T1-T12
lumbar vertebrae
L1-L5, lower back, third set of 5 larger vertebrae, which forms the inward curve of the spine
Vertebrae
26 irregular bones that make up the spine Cervical, thoracic, lumbar, sacrum, coccyx
sacrum
5 fused vertebrae, inferior to the lumbar vertebrae that articulates with the hip bones
cervical vertebrae
7 vertebrae in the neck (C1-C7)
General Structure of Vertebrae
Body (centrum), spinous process, vertebral arch, lamina, transverse process, pedicle, vertebral foremen, paired superior and inferior articular processes
vertebra prominens
C7, used as a landmark for counting vertebrae because it's large spinous process of C7 is palpable through the skin and isn't bifid
Regional Characteristics of Axis
Dens (odontoid process) sticks through vertebral foramen, allows head to pivot side to side (shake no), no body
Regional Characteristics of Thoracic Vertebrae
Round vertebral foramen, only one with facet for tubercle of rib, longest spinous process
body of vertebrae
Solid, thick, disc-shaped, and weight bearing anterior portion of Vertebrae
transverse process
Two lateral projections that extend from each side of the vertebral arch
Regional Characteristics of Cervical Vertebrae 3-7
body is oval, short spinous process split at the tip, large triangular vertebral foramen, transverse processes contain foramina, superior and inferior articular processes
Regional Characteristics of Lumbar Vertebrae
body is thicc, spinous process shaped like an axe/hatchet
lateral masses
bony junction between the superior and inferior articular processes; has articular facets on both its superior and inferior surfaces
vertebral arch
composed of pedicles, laminae, and a spinous process, it represents the junction of all posterior extensions from the vertebral body
cervical curvature
concave posteriorly; develops as baby learns to hold head upright; C1-C7
lumbar curvature
concave posteriorly; develops as baby learns to stand and walk; L1-L5
coccyx
four vertebrae fused together to form the tailbone
Regional Characteristics of Atlas
has no body or spinous process; Ring of bone with anterior arches, posterior arches, and lateral masses (with articular facets on superior and inferior surfaces) directly articulate with skull so you can move head up and down (nod yes),
odontoid process (dens)
knob like process on superior surface of axis and acts as a pivot
intervertebral foramina
lateral openings between adjacent vertebrae that the spinal nerves pass through
spinous process
median posterior projection arising at the junction of the two laminae
transverse foramen
only found in the transverse processes of cervical vertebrae; vertebral arteries pass through to service the brain
vertebral foramen
opening enclosed by the body and vertebral arch; form the long vertebral canal, through which the spinal cord passes
lamina
part of the vertebral arch
superior articular process
protrudes superiorly from the pedicle-lamina junctions; articulates with inferior articular process of vertebra above
pedicle
short bony pillars projecting posteriorly from the vertebral body, form the sides of the arch
thoracic vertebrae
the second set of 12 vertebrae (T1-T12); form the outward curve of the spine, articulate with the ribs