Axial skeleton 2 Flashcards
Vertebral Column
Composed of a series of bones called vertebrae
Between each pair of (non-fused) vertebrae is an intervertebral (IV) disc
Column is held together by a host of ligaments
Functions:
Protect the spinal cord (vertebral canal)
Attachment point for muscles, the ribs, and the pelvic girdle
Support the head
Regions of the Vertebral Column
Cervical Region
7 vertebrae – C1-C7
Thoracic Region
12 vertebrae – T1-T12
Lumbar Region
5 vertebrae – L1-L5
Sacrum
5 fused vertebrae – S1-S5
Coccyx
2-4 fused vertebrae – Co1-Co4
4 Normal Curves of the Vertebral Column adult
Cervical Curve
Convex anteriorly
Thoracic Curve
Convex posteriorly
Lumbar Curve
Convex anteriorly
Sacral Curve
Convex posteriorly
Functions of the curves in the spine
Functions:
Increase the strength of the vertebral column
Shock absorption
Help maintain balance in the upright posture
Parts of a Typical Vertebra (except for c1)
Blocky part - body
Vertebral arch - spiky part
- both surround the…
Vertebral foramen -
Collectively, these form the vertebral canal, which contains the spinal cord
Parts of a Typical Vertebra of the vertebral arch
Lamina (2) the groove inbtween the processes
Transfverse process (2) angled spike
Spinous Process straight spike
Pedicle (2) anterior to the transverse process
Superior articular process (2)
Inferior articular process (2)
-Forms the Zygapophyseal
(facet) joint (2)
and Intervertebral
disc
left and right Intervertebral foramen (2) -
Spinal nerves
Intervertebral (IV) Discs and functions
Annulus fibrosus – outer ring of fibrocartilage
Nucleus pulposus – inner elastic core
Function to absorb vertical forces on the vertebral column
Flatten when compressed (height changes) and loses water
INTERVERTEBRAL DISC HERNIATION
Acute or chronic trauma/strain on the IV discs can damage (tear) the annulus fibrosus
If the damage is sufficient, the nucleus pulposus can protrude (herniate) through the annulus fibrosus into the vertebral foramen
Most commonly, the nucleus herniates posterolaterally
Compression of spinal nerves or spinal nerve roots (“radiculopathy”)
Pain and sensory/motor symptoms on one side of the body (dermatomal/myotomal pattern)
Occasionally, the nucleus herniates posteriorly
Compression of the spinal cord or cauda equina (“myelopathy”)
Pain and sensory/motor symptoms on both sides of the body (upper and/or lower limbs)
Other symptoms – trouble walking/balancing, problems with fine motor control, bower/bladder symptoms
Regional Vertebral Differences
The vertebrae throughout the spine are generally similar in structure
However, the vertebrae in each region of the spine have some specific (and sometimes unique) features
Cervical vertebrae characteristic
Specific Features:
Small vertebral body
Large vertebral foramen
Small transverse processes
Bifid spinous process - tip is split
Transverse foramen (2) - Vertebral artery
Vertebral vein
Thoracic vertebrae characteristic
Specific Features:
Longer transverse processes
Long, inferiorly-directed spinous process
Facet on transverse process (for rib tubercle) T11-T12 do not have this facet
Superior demifacet on the body (for rib head)
Inferior demifacet on the body (for rib head) T9-T12 only have one facet for the rib heads
Lumbar vertebrae characteristic
Specific Features:
Largest
Short and blunt spinous process
Atlas (C1)
Specific Features:
NO BODY
NO SPINOUS PROCESS
Anterior & posterior arches
Lateral masses (2)
Superior articular facets - Occipital bone
Atlanto-occipital joints
Axis (C2)
Specific Features:
Large spinous process
Odontoid process (dens) - Atlas (anterior arch) Atlanto-axial joint
- extents superior to the vertabrae, tooth like
How are c1 and c2 connected
the den of the c2 rests in the c1 and is held together by the transverse ligament
