Vertebral Column and Spinal Cord Flashcards
Cervical Vertebrae
Transverse Foramina β’ Bifid Spinous Process β’ Uncinate Process β’ Small Vertebral Body β’ Large Vertebral Foramen
Thoracic Vertebra
- Superior and Inferior Costal Facets β’ Transverse Costal Facets
- Long Spinous Process
- Heart Shaped Vertebral Body
- Spinous process oriented Inferiorly
Lumbar Vertebrae
- Largest and thick Vertebral Body
- Mamillary Processes
- Short Horizontal Transverse process β’ Short Spinous Process
- Triangular Vertebral Foramen
Intervertebral Discs
Classified as a cartilaginous joint
Outer anulus fibrous surrounds the inner / central nucleus pulposus
Joints and Ligaments of the Atlas, Axis, and Skull
There are 3 Atlanto-axial joints: 2 lateral and 1 median.
The median joint occurs between the dens of C2 and the posterior surface of the anterior arch of C1.
The lateral articulations are between the inferior articular facet of C1 and the superior articular facet of C2
The medial joint is secured posteriorly by the transverse ligament of the atlas.
Superior and inferior longitudinal bands of the Cruciate lig. passes from the transverse ligament to the occipital bone superiorly and inferiorly to the body of C2.
Alar ligaments
laterally from dens to skull
Apical ligament -
is deep to the cruciate ligament, attaching the dens to the skull.
Movement of the Atlas, Axis, and Skull
permits the head to be turned from side to side
β’ During this movement, the cranium and C1 rotate as a unit over C2. As the head rotates to the side, the dens of C2 is the axis point or pivot.
Transverse Ligament Rupture
The dens is no longer supported
Crushes the spine
Kyphosis (βhunchbackβ)
an abnormal increase in the thoracic curvature, leading to a posterior protrusion of the vertebral column
Lordosis
is characterized by an anterior tilting of the pelvis (the upper sacrum is flexed or rotated antero- inferiorly) with increased inward curve of the spine
Scoliosis
common in young adults and is characterized by an abnormal lateral curvature that is accompanied by rotation of the vertebrae
The Spinal Cord-Tapers off
conus medularis
β’ Cauda equina
the lumbosacral nerve roots (ventral and dorsal) that continues into the lumbar cistern
Blood Supply to the Spinal Cord
Longitudinal artery originate from vertebral artery
Location: one anterior and two posterior spinal
Blood Supply to Spinal Cord: Segmental Supply
Cervical
Vertebral artery
Blood Supply to Spinal Cord: Segmental Supply
Thoracic
Posterior intercostal artery
Blood Supply to Spinal Cord: Segmental Supply
Lumbar
Lumbar artery
Blood Supply to Spinal Cord: Segmental Supply
Sacrum
Lateral sacral artery
Two types of segmental blood supply:
Segmentalmedullaryarterieswhich anastomose with the longitudinal spinal arteries
β’ SegmentalRadicularbranchesthat supply the dorsal and ventral roots
Artery of Adamkiewicz
Great anterior segmental medullary artery (Artery of Adamkiewicz)
β’ Largest segmental medullary artery
β’ Arises from the lower thoracic or upper
lumbar region
β’ Important source of blood supply to lower lumbar and sacral parts
Venous Drainage of Spinal Cord
The anterior and posterior spinal veins drain the spinal cord
β’ Spinal veins drain into internal vertebral venous (Batsonβs) plexus located in the epidural space
β’ Batsonβs plexus also communicate with pelvic veins, Dural venous sinuses of the cranial vault, and external vertebral venous plexus
β’ Epidural space
surrounds the dura mater. Contains spinal nerve roots, loose fatty tissue, small arteries, and the internal vertebral venous plexus of Bateson
Subdural Space
β potential space
Subarachnoid space
contains CSF and major arteries
Dural Sac
Dural sac/Lumbar cistern- contains cauda equina (dorsal & ventral roots of spinal nerves), filum terminale, and CSF
L1/L2
The Lumbar Puncture
Skin - supracristal line - ligamentum flavum - dura
Lumbar puncture is not performed in the presence of increased intracranial pressure.
The Lumbar Puncture-Adults
performed between L3/L4 or L4/L5
The Lumbar Puncture- children
Between L4/5
The Lumbar Puncture Layersβ Sagittal section
Skin Subcutaneous tissue Supraspinous ligament Interspinous ligament Ligamentum flavum Epidural space Dura mater Arachnoid mater Subarachnoid space