Spine Flashcards
5th Lumbar vertebrae
The fifth lumbar vertebra is the largest of the lumbar vertebrae. It is an atypical lumbar vertebra.
5th Lumbar vertebrae: Gross anatomy
Location: most inferior lumbar vertebrae
Anterior components:
- Body: large and wide
Posterior components:
- Pedicles – project backward
- Transverse processes – short, massive and pyramidal, project from the pedicles
- Lamina: broad, thick and minimally overlapping
- Facets: oblique in orientation
- Articular processes – superior and inferior
- Spinous process – single, short, thick and roughly horizontal
5th lumbar vertebrae: articulations
- Superior articular facet with the inferior articular facet of L4
- Inferior articular facet with the superior articular facet of the sacrum
- Intervertebral discs both superior and inferior
5th Lumbar vertebrae: relations
- Anterior: Anterior longitudinal ligament, union of the common iliac veins
- Posterior: Supraspinous ligament, erector spinae muscles, External vertebral venous plexus
- Lateral: iliolumbar ligaments, quadratus lumborum muscles, intertransverse ligaments
- Superior: L4
- Inferior: S1
- Central: cauda equina, basivertebrasl veins, internal vertebral venous plexus
5th Lumbar vertebrae: ligaments
- Anterior longitudinal ligament
- Posterior longitudinal ligament
- Ligamentum flavum
- Supraspinous ligament
- Interspinous ligament
- Intertransverse ligaments
- Iliolumbar ligaments
5th Lumbar vertebra: variants
- Sacralisation of L5/Lumboralisation of S1
- Incomplete posterior arch
- Limbus vertebrae
- Block vertebrae
- Hemivertebrae
- Butterfly vertebrae
- Posterior element fusion
7th cervical vertebra: Description
The seventh cervical vertebra is the most inferior of the cervical vertebra, also known as the vertebra prominens (due to it’s long palpable spinous process). It has some features distinct from the other cervical vertebrae making it one of the atypical vertebrae.
7th cervical vertebra: Gross anatomy
Anterior components:
- Body ovoid in shape with uncinated process from the lateral aspects of the superior end plates
- Pedicles that are direct posterolateral attaching the body midway such that the superior and inferior notches are the similar in depth
- Bilateral transverse process with anterior and posterior tubercles
- Small transverse foramina as they do not transmit the vertebral arteries
- intertubercular lamella of the transverse process
Posterior components:
- Superior and inferior articular process superior facing backward and upward, inferior facing anterior and inferior
- Lamina forming a wide vertebral arch with large vertebral foramen
- Long spinous process ending in a tubercle (not bifid as in typical cervical vertebrae)
7th cervical vertebra: articulations
- Superior and inferior articular facets with the facets above and below
- Intervertebral discs both superior and inferior
- Uncovertebral joint with C6
7th cervical vertebra: Vasculature
Arterial supply:
Branches from the ascending cervical and vertebral arteries
Venous drainage:
Basivertebral veins, internal and external vertebral venous plexi
7th cervical vertebra: variants
- C7 may possess a cervical rib
- C7 foramen may transmit the posterior vertebral vein (if doubled), and may transmit the grey ramus from the inferior cervical ganglion to the anterior ramus of C7
- vertebral artery may enter at this level (usually it enters the cervical transverse foramen at C6)
- serves as the attachment for scalenus pleuralis (variant)
Atlas: Description
The atlas (C1) is an atypical cervical vertrebrae.
Location: The most superior vertebrae of the spinal column
Function: support and movement of the head, protection of the spinal cord, passage of vessels
Atlas: Gross anatomy
Anterior components:
Anterior arch with articular facet for the dens
lateral masses with foramina bilaterally from the vertebral arteries
Posterior elements:
Posterior arch without a spinous process
Atlas: Relations
- Superior: basiocciput
- Inferior: C2 vertebrae
- Lateral: vertebral arteries, sternocleidomastoid
- Medial: spinal cord
- Anterior fossa of rossenmulla, nasopharynx
- Posterior: ligamentum nuchae
Atlas: Articulations
- Antlanto-occipital joints – hyaline covered synovial joint between the occipital condyles and concave articular facet of the lateral masses
- Medial atlanto-axial joint – hyaline covered synovial joint between the dens of the axis and the posterior aspect of the anterior arch of the atlas
- Lateral atlanto-axial joint – hyaline covered synovial joint between the inferior articular facet of the atlas and the superior articular facet of the axis
Atlas: Ligaments
- Anterior longitudinal ligament
- Posterior longitudinal ligament
- Intertransverse ligament
- Apical ligaments – tip of dens to foramen magnum
- Alar ligaments – Lateral of the tip of the dens to the foramen magnum
- Cruciform ligament – longitudinal band and transverse band
- Ligamentum flavum
- Accessory ligament – C2 body to the lateral masses of C1
- Tectorial membrane
Atlas: Neurovasculature
Arterial supply:
- Branches of the vertebral artery
Venous drainage: venous plexi of the spine
Innervation: C1
Atlas: Variants
- Os ondontoidium
- Os terminale
- Incomplete anterior arch
- Incomplete posterior arch
- Osscile of the ligamentum nuchae
- Fusion to occiput
- Block vertebra to the C2
- Limbus vertebrae
- Proatlantal artery
Axis: Description
The axis (C2) is the second cervical vertebra. It is an atypical cervical vertebra.
Location: between the atlas and C3
Function:
Support the head, axis for rotation of the head, transmits the spinal cord and vertebral arteries
Axis: Gross anatomy
- Irregular bone
- Anterior components:
- Dens
- Body
- Lateral masses
- Transverse processes with formina transversarium
- Superior articular facets
- Inferior articular facets
- Posterior elements:
- Pedicles
- Lamina
- Spinous process – typically bifid
Axis: Articulations
- Superior articular facet with the inferior articular facet of the atlas
- Dens articulates with the posterior aspect of the anterior arch of C1
- Inferior articular facet with the superior articular facet of C3
- Uncovertebral articulation with C3
- Intervertebral joint with C3 via the C2/C3 intervertebral disc
Axis: Relations
- Anterior: Anterior longitudinal ligament
- Posterior: ligamentum nuchae
- Lateral: vertebral arteries and veins
- Superior-posterior: sub-occipital triangle
- Centrally: spinal cord and basivertebral veins
Axis: Ligaments
- Cruciform ligament
- Apical ligament
- Alar ligaments
- Accessory ligaments
- Tectorial membrane
- Ligamentum flavum
- Anterior and posterior longitudinal ligaments
- Intertransverse ligaments (minor in the c-spine)
- Interspinous ligaments
- Supraspinous ligaments
Axis: Variants
- Os ondontoidium
- Persistent os terminale
- Bifid or non-bifid spinous process
- Aplasia/hypoplasia
Typical thoracic vertebra: Description
T2 to T8 are considered typical thoracic vertebrae.
Typical Thoracic vertebra: Gross anatomy
Relative to cervical and lumbar vertebrae, thoracic vertebrae have:
- medium-sized, heart shaped vertebral bodies
- medium-sized vertebral canal
- prominent transverse processes with costal facets
- long spinous processes angulating downwards
Typical thoracic vertebra: Features
Anterior components of thoracic vertebrae:
- body
- pedicle
- superior and inferior costal demifacets
Posterior components of typical thoracic vertebrae:
- downward angled spinous processes
- transverse processes with transverse costal facets
- Superior and inferior articular facets
- lamina
- intervertebral foramen
Typical thoracic vertebra: Articulations
Ribs
Each vertebra contains three points of articulation with ribs.
- The superior demifacet of a thoracic vertebra articulates with the corresponding rib (costovertebral joint).
- This rib articulates again with the costal facet on the transverse process (costotransverse joint).
- The inferior demifacet articulates with the rib below.
Intervertebral:
Facet (zygapophyseal) Joints
- The superior articular process arises from the upper border of pedicle. An oval facet faces posterolaterally.
- The inferior articular process arises from the lower border of the pedicle. The facets face anteromedially.
Intervertebral discs
- Similar to other vertebrae, discs are interposed between hyaline cartilage on the centrum of the vertebral bodies. The disc height is slightly less than cervical vertebrae.