Overview
This lecture explains how to distinguish between cervical, thoracic, and lumbar vertebrae by their unique anatomical features.
Cervical Vertebrae
- Cervical vertebrae are neck bones identified by holes (transverse foramina) in their transverse processes.
- These vertebrae have a smaller size and a relatively horizontal spinous process.
- The atlas (C1) supports the head and attaches to the occipital condyles; it has transverse foramina.
- The axis (C2) lies below the atlas and features the dens, a unique upward projection allowing head rotation.
- Only cervical vertebrae have transverse foramina.
Thoracic Vertebrae
- Thoracic vertebrae are found in the mid-back and connect to the ribs.
- They are recognized by small indentations called costal demi-facets, which articulate with the heads of ribs.
- The spinous process of thoracic vertebrae points downward.
Lumbar Vertebrae
- Lumbar vertebrae make up the lower back and have the largest vertebral bodies for weight-bearing.
- These vertebrae have a thick, stout spinous process.
- Their shape is broad and robust compared to cervical and thoracic vertebrae.
Key Terms & Definitions
- Transverse foramina â openings in the transverse processes of cervical vertebrae, unique to this group.
- Atlas (C1) â the first cervical vertebra; supports the skull and allows nodding movement.
- Axis (C2) â the second cervical vertebra; contains the dens, enabling head rotation.
- Dens â upward projection on the axis that the atlas pivots around.
- Costal demi-facets â small indented areas on thoracic vertebrae for rib attachment.
Action Items / Next Steps
- Review the distinguishing characteristics of cervical, thoracic, and lumbar vertebrae.
- Memorize features of the atlas and axis for identification.
- Practice identifying vertebrae types on diagrams or models.