Overview
This lecture explains how to distinguish between cervical, thoracic, and lumbar vertebrae by their key anatomical features.
Cervical Vertebrae
- Cervical vertebrae are located in the neck region.
- They are identified by the presence of transverse foramina (holes in the transverse processes).
- Cervical vertebrae are smaller than thoracic or lumbar vertebrae.
- The spinous process of cervical vertebrae runs fairly parallel.
Special Cervical Vertebrae: Atlas and Axis
- The atlas (C1) supports the head and connects to the occipital condyles.
- Like all cervical vertebrae, the atlas has transverse foramina.
- The axis (C2) has a unique structure called the dens, which allows head rotation.
- The atlas sits on top of the axis and pivots around the dens.
Thoracic Vertebrae
- Thoracic vertebrae are found in the middle back.
- They have costal demi-facets (small indentations) for rib attachment.
- The spinous process points downward.
- Thoracic vertebrae can be distinguished from cervical and lumbar by these features.
Lumbar Vertebrae
- Lumbar vertebrae form the lower back.
- They have a very large vertebral body and a stout spinous process.
- Lumbar vertebrae are the largest and most robust of the three types.
Key Terms & Definitions
- Transverse Foramen — Hole in each transverse process of cervical vertebrae for blood vessels.
- Atlas (C1) — First cervical vertebra that supports the head and connects to the skull.
- Axis (C2) — Second cervical vertebra with the dens, enabling head rotation.
- Dens — Peglike projection on the axis for pivoting the atlas and skull.
- Costal Demi-Facet — Small indention on thoracic vertebrae for rib attachment.
- Spinous Process — Posterior projection from a vertebra’s arch.
Action Items / Next Steps
- Review models or images of each vertebra type (cervical, thoracic, lumbar) to practice identification.
- Memorize the unique features of the atlas and axis.
- Be able to define key terms and match them to the correct vertebrae.