Vertebral column, spinal cord and autonomic nervous system — Vocabulary flashcards (ANES817)

Vocabulary flashcards covering vertebral anatomy, spinal nerves, meninges, and autonomic nervous system concepts from the lecture notes.

Vertebral column

The segmented bony column (cervical, thoracic, lumbar, sacral, coccygeal) that protects the spinal cord and serves as an attachment for ribs and muscles.

Cervical vertebrae

The seven neck vertebrae; features include bifid spinous process, foramen transversarium, triangular canal, and uncinate processes.

Thoracic vertebrae

Twelve vertebrae with heart-shaped bodies, facets for ribs, long spinous processes, and demifacets on the bodies.

Lumbar vertebrae

Five lower-back vertebrae with large cylindrical bodies, triangular vertebral foramen, and hatchet-shaped spinous processes.

Sacral vertebrae

Five fused vertebrae forming the sacrum, articulating with ilium and coccyx; contains sacral foramina and promontory.

Coccygeal vertebrae

Four fused vertebrae at the tail end; articulates with the sacrum and contains no vertebral canal.

Intervertebral foramen

Opening formed by the notches of adjacent vertebrae through which a spinal nerve exits the vertebral canal.

Vertebral canal

The bony tunnel formed by vertebral foramina that houses the spinal cord.

Pedicle

The short bony bridge connecting the vertebral body to the vertebral arch.

Lamina

Part of the vertebral arch between the transverse process and spinous process; forms the posterior arch.

Spinous process

Posterior projection of the vertebral arch; varies by region (long in thoracic, hatchet-shaped in lumbar).

Transverse process

Lateral projections from the vertebral arch; articulate with ribs in thoracic vertebrae and provide muscle attachments.

Superior articular process

Upper facet that forms a zygapophysial joint with the inferior articular process of the vertebra above.

Inferior articular process

Lower facet that forms a zygapophysial joint with the superior articular process of the vertebra below.

Zygapophysial joint

Facet joints between superior and inferior articular processes; stabilize and guide movement of the spine.

Body (vertebral body)

The thick anterior portion of a vertebra that bears weight.

Foramen transversarium

Opening in cervical vertebrae through which the vertebral artery and vein pass.

Uncinate process

Hook-like process on the superior surface of C3–C7 vertebrae forming uncovertebral joints.

Atlas (C1)

First cervical vertebra; supports the skull, lacks a vertebral body, articulates with occipital condyles; allows head nodding.

Axis (C2)

Second cervical vertebra; contains the dens odontoid process which acts as a pivot for C1 rotation.

Dens (odontoid process)

Peg-like projection on C2 that acts as the pivot for the atlas and skull.

Atlanto-axial joint

Joint between C1 (atlas) and C2 (axis) permitting rotation of the head.

Occipital condyles

Articulating surfaces on the skull that interact with C1 to permit nodding.

Demifacet

Partial facet on a vertebral body for articulation with a rib (costovertebral joint).

Demifacets (thoracic)

Partial facets on thoracic bodies for articulation with heads of ribs; each vertebra articulates with its own rib and the one above.

Thoracic vertebrae features

Heart-shaped bodies, facets for ribs, long spinous processes, circular vertebral canal, and demifacets.

Sacrum

Five fused vertebrae forming a triangular bone; articulates with ilium and coccyx; contains anterior/posterior sacral foramina and promontory.

Sacral foramina

Pairs of openings on the sacrum for ventral and dorsal rami to pass.

Coccyx

Small triangular bone at the end of the vertebral column; articulates with the sacrum and contains no vertebral arch.

Intervertebral disc

Cartilaginous disc between adjacent vertebral bodies consisting of a nucleus pulposus and anulus fibrosus.

Nucleus pulposus

Gel-like center of an intervertebral disc that can herniate posteriorly.

Annulus fibrosus

Outer fibrous ring of an intervertebral disc surrounding the nucleus pulposus.

Disc herniation

Herniation of nucleus pulposus usually posterolateral, compressing the exiting nerve (disc + 1 rule).

Posterior longitudinal ligament

Ligament along the posterior aspect of vertebral bodies; resists flexion; narrower than anterior ligament.

Ligamentum flavum

Ligament connecting adjacent laminae; helps close the vertebral canal and resists flexion.

Anterior longitudinal ligament

Ligament along the anterior surface of vertebral bodies; resists excessive extension.

Interspinous ligament

Ligament connecting adjacent spinous processes.

Supraspinous ligament

Ligament along the tips of spinous processes; becomes ligamentum nuchae in the neck.

Ligamentum nuchae

Expanded supraspinous ligament in the neck that serves as an attachment for neck muscles.

Meninges

Three protective membranes surrounding the spinal cord: dura mater, arachnoid mater, and pia mater.

Dura mater

Outer, thick protective layer; forms the dural sac and is separated from bone by the epidural space.

Arachnoid mater

Delicate middle layer; contains the subarachnoid space with CSF; ends near S2.

Pia mater

Innermost vascular membrane firmly adherent to the spinal cord; denticulate ligaments are extensions of pia.

Denticulate ligament

Extensions of pia mater that segment and anchor the spinal cord between dorsal and ventral rootlets.

Filum terminale internum

Pial portion of the filum terminale located inside the dural sac.

Filum terminale externum

Dural portion of the filum terminale outside the dural sac; also called coccygeal ligament.

Conus medullaris

Tapered end of the spinal cord, typically at L1–L2 in adults.

Cauda equina

Bundle of lumbar/sacral nerve roots descending below the conus medullaris in the lumbar canal.

Spinal nerves (31 pairs)

31 pairs of mixed nerves (C1–C8, T1–T12, L1–L5, S1–S5, Co1) exiting via intervertebral foramina; C1–C7 exit above their vertebrae, C8 exits between C7 and T1.

Dorsal root

Sensory root carrying afferent fibers; contains the dorsal root ganglion with sensory neuron cell bodies.

Ventral root

Motor root carrying efferent fibers; cell bodies in the ventral horn.

Dorsal ramus

Branch of a spinal nerve supplying the back; contains both sensory and motor fibers.

Ventral ramus

Branch supplying the ventral body wall and limbs; carries mixed sensory and motor fibers.

White ramus communicans

Preganglionic sympathetic fibers traveling from spinal nerves to sympathetic chain ganglia; present at T1–L2.

Grey ramus communicans

Postganglionic sympathetic fibers traveling from chain ganglia back to spinal nerves; present at all levels.

Splanchnic nerve

Preganglionic sympathetic fibers that bypass chain ganglia and synapse in collateral (prevertebral) ganglia.

Cardiac nerve

Sympathetic postganglionic nerve supplying the heart; part of thoracic sympathetic pathways.

Sympathetic nervous system (SNS)

Thoracolumbar division of the autonomic system; uses norepinephrine/epinephrine; mediates flight-or-fight responses.

Parasympathetic nervous system (PNS)

Craniosacral division of the autonomic system; uses acetylcholine; promotes rest-and-digest activities.

Craniosacral origin

Describes the parasympathetic system originating from brainstem (cranial) and sacral spinal cord.

Dermatome

Skin region innervated by a single spinal nerve; used to map sensory loss and local anesthesia.

Viscerotome

Map of referred visceral pain areas corresponding to somatic regions.