1/22/2020 Learning objectives THE NORMAL SPINE: Anatomy of the vertebral column - • Describe the parts of the vertebral column and number of bones in each part Bones & Disks • Describe the curves of the vertebral column • Describe a typical vertebra in each part of the vertebral column and the Maria T. Tzalonikou features of the sacrum and the coccyx Radiologist, Athens, GREECE • Describe the intervertebral discs and their structure European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 Vertebral column • Viewed form anteriorly: 2 pyramids joined together • Viewed laterally: cervical, thoracic, lumbar, sacrococcygeal curves, • Midline structure at the dorsal aspect of the skeleton, • Summit: upper surface of the atlas, central axis of the human skeleton Base: undersurface of the 5th lumbar spine vertebra, • Supports the head-neck & body, • Anterior Surface: vertebral bodies & intervertebral discs allows movement, absorbs shocks & protects the spinal cord • Posterior Surface: spinous processes • Flexible column with 33 vertebrae • Lateral surfaces: vertebral bodies, facets & intervertebral foramina European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 • Viewed form anteriorly: 2 pyramids joined together • Viewed form anteriorly: 2 pyramids joined together • Viewed laterally: cervical, thoracic, lumbar, sacrococcygeal curves, • Viewed laterally: cervical, thoracic, lumbar, sacrococcygeal curves, • Summit: upper surface of the atlas, • Summit: upper surface of the atlas, Base: undersurface of the 5th lumbar spine vertebra, Base: undersurface of the 5th lumbar spine vertebra, • Anterior Surface: vertebral bodies & intervertebral discs • Anterior Surface: vertebral bodies & intervertebral discs • Posterior Surface: spinous processes • Posterior Surface: spinous processes • Lateral surfaces: vertebral bodies, facets & intervertebral foramina • Lateral surfaces: vertebral bodies, facets & intervertebral foramina European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 1/22/2020 • Viewed form anteriorly: 2 pyramids joined together • Viewed form anteriorly: 2 pyramids joined together • Viewed laterally: cervical, thoracic, lumbar, sacrococcygeal curves, • Viewed laterally: cervical, thoracic, lumbar, sacrococcygeal curves, • Summit: upper surface of the atlas, • Summit: upper surface of the atlas, Base: undersurface of the 5th lumbar spine vertebra, Base: undersurface of the 5th lumbar spine vertebra, • Anterior Surface: vertebral bodies & intervertebral discs • Anterior Surface: vertebral bodies & intervertebral discs • Posterior Surface: spinous processes • Posterior Surface: spinous processes • Lateral surfaces: vertebral bodies, facets & intervertebral foramina • Lateral surfaces: vertebral bodies, facets & intervertebral foramina European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 • Viewed form anteriorly: 2 pyramids joined together • Viewed laterally: cervical, thoracic, lumbar, sacrococcygeal curves, • 33 vertebrae: • Summit: upper surface of the atlas, 7 cervical, 12 thoracic, 5 lumbar, Base: undersurface of the 5th lumbar spine vertebra, 5 sacral, 4-5 coccygeal • Anterior Surface: vertebral bodies & intervertebral discs • Articulating: cervical, thoracic, lumbar • Posterior Surface: spinous processes Fused: sacrum, coccyx • Lateral surfaces: vertebral bodies, facets & intervertebral foramina European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 General characteristics of a General characteristics of a vertebral body vertebral body Body Arch European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 1/22/2020 • Body: cylindrical, getting larger towards the lumbar vertebrae • Pedicles: part of the neural arch, short, projecting posteriorly • Laminae: broad plates that complete the neural arch, enclose spinal foramen • Spinous process: midline structure, projecting posteriorly • Articular processes: superior - inferior processes • Transverse processes: project laterally European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 Cervical spine vertebral body • C1-C7, the smallest of all vertebrae • Body: dense, broader from side to side • Pedicles: directed outward and backward Axon: straight line around which an object may be located, move in a symmetric way or rotate • Laminae: narrow • Transverse processes: short, downward-outward-forward direction, bifid • Articular processes: flat and oblique • Spinous processes: short and bifid European Course on Spine Radiology, Rome, 22-25 January 2020 Thoracic spine vertebral body • T1-T12, intermediate in size • Body: resemble to cervical-lumbar vertebrae at the respective ends • Pedicles: backward direction • Laminae: broad, thick • Transverse processes: thick and of great length • Articular processes: flat and nearly vertical • Spinous processes: long, triangular, oblique downward direction Gray’s Anatomy European Course on Spine Radiology, Rome, 22-25 January 2020 1/22/2020 Lumbar spine vertebral body • L1-L5 - the largest of all vertebrae • Body: large, greater diameter from side to side • Pedicles: strong, directed backward • Laminae: narrow • Transverse processes: long, slender, outward direction • Articular processes: superior concave - inferior convex • Spinous processes: thick, broad, square shaped and of horizontal direction European Course on Spine Radiology, Rome, 22-25 January 2020 Gray’s Anatomy Sacrum • S1-S5, large triangular, pyramid shaped bone • Fused vertebral bodies • Between the innominate bones • Anterior surface: sacral foramina • Posterior surface: medial sacral crest, posterior sacral foramina, lateral sacral crests • Lateral articular surfaces, base & apex European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 1/22/2020 Coccyx Articulations of the Spine • Amphiarthroses: between vertebral bodies • Diarhtroses: between facet joints • Synarthroses (syndesmoses): between the lamina, between the spinous and between the transverse processes Nig. J. of Cl. Pract., 2017 • Specific articulations: cranio-vertebral articulations (atlanto-occipital, atlantoaxial), thoraco-vertebral and sacro-iliac joints European Course on Spine Radiology, Rome, 22-25 January 2020 Gray’s Anatomy European Course on Spine Radiology, Rome, 22-25 January 2020 Intervertebral Discs • 23 intervertebral discs • Lie between adjacent vertebrae in the the vertebral column • 1/4 - 1/3 of the height of the vertebral column • Allow slight movement of the vertebrae, contribute to shock absorption & compressive load transmission • Fibrocartilagenous joints • Thinnest in thoracic spine, thickest in lumbar spine European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 Annulus fibrosus Nucleus pulposus • Concentric lamellae of highly organized collagen type I and type II fibers • Lamellae thicker anteriorly and laterally, thinner posteriorly • Contains proteoglycans • Collagen bundles pass obliquely and connect to the vertebral bodies • About 80-90% water • Peripheral fibers attach to the anterior and posterior longitudinal ligaments • Possesses compressibility, distributes pressure evenly across the disc • Contains nucleus pulposus and withstands compressive forces European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 1/22/2020 Nucleus pulposus • Contains proteoglycans • About 80-90% water • Possesses compressibility, distributes pressure evenly across the disc European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 Blood supply & Innervation Blood supply & Innervation • Blood supply • Blood supply avascular disc: capillaries terminate at the end plates avascular disc: capillaries terminate at the end plates nutrition to nucleus pulposus: through diffusion nutrition to nucleus pulposus: through diffusion • Innervation: • Innervation: sinuvertebral nerve and sympathetic trunk via multiple gray rami communicantes, sinuvertebral nerve and sympathetic trunk via multiple gray rami communicantes, neuropeptides (?) participate in sensory transmission neuropeptides (?) participate in sensory transmission European Course on Spine Radiology, Rome, 22-25 January 2020 European Course on Spine Radiology, Rome, 22-25 January 2020 In Summary • Description of the parts of the vertebral column and number of bones in each part • Description the curves of the vertebral column • Description of a typical vertebra in each part of the vertebral column and the features of the sacrum and the coccyx • Description of the intervertebral discs and their structure European Course on Spine Radiology, Rome, 22-25 January 2020.